Perth Observatory Galaxia Magazine | December 2023

DECEMBER 2023 Photographing Meteor Showers Make sure you’re ready to take beautiful shots of 2024’s meteor showers

The Euclid Space Telescope A new space telescope has released its first images and is now on the hunt for dark energy

A Correct Time For All Find out how Western Australian Standard Time was developed and Perth Observatory’s role in Implementing it

What’s In The Night Sky This January, February, and March Find out what to see in our southern night sky

GALAXIA MAGAZINE

Discover an extraordinary blend of family fun and learning this school holidays at the Perth Observatory!

Embark on captivating Historical Tours, and safely see our glorious Sun through our Solar Telescope. Learn to capture the magic of the night sky at our Astrophotography Stall, and journey through the cosmos with our VR headsets.

Also engage in hands-on activities as you contribute to our Space Mural, and dive into the citizen science.

Come along to explore Western Australia’s oldest observatory and get an introduction to the stars! Great for space addicts and those just beginning their space journey

INTRO TO THE STARS FESTIVAL

Get an introduction To The Stars On The 21st Of January

Exploration is wired into our brains. If we can see the horizon, we want to know what’s beyond.

- Buzz Aldrin, Apollo 11 Astronaut

Contents

05 A View Through The Eyepiece 09 Photographing Meteor Showers 16 ‘Sup, er, Nova?

19 The Euclid Space Telescope 27 Are We Fired?

29 Remote Citizen Science 33 Cosmic Treasures

Find Us Here

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35 Saturn’s Bling on the Edge 37 A Correct Time For All 47 Time-Traveling Artistry 51 What’s In January’s Skies 54 What’s In February’s Skies 57 What’s In March’s Skies 61 Southern Lights Cocktail

Editorial

Contributors

Subscriptions

Front Cover Image By

Matt Woods Editor

Michelle Ashley-Emile, Amber Berriman, Paul, Fisher, Roger Groom, Rashel Jahan, Paul Jones, Beryl Keaughran, Louise Kaestner, Ronny Kaplanian, Matt Woods, and Brad Young

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Grahame Kelaher

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Back Cover Image By Roger Groom

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A View Through The Eyepiece

2023 has been a year of celestial marvels and astronomical adventures at Perth Observatory. Stargazing events all over Western Australia, the Total Solar Eclipse in Exmouth, a TEDx talk and a wedding, new telescopes and equipment, aurora, bright meteors, and fascinating workshops that unlocked the mysteries of the cosmos for people taking they’re first steps into a much larger world. It has truly been a stellar journey.

The Perth Observatory staff and volunteers extends warm wishes to you and your loved ones and we hope you all have a joyous holiday season filled with celestial wonders and astronomical delights! Whether you’re spending time with loved ones, indulging in festive treats, or simply gazing at the night sky, may your days be merry and bright.

Next Year, it’s lights out and away we go, as we are running a number of astrophotography worshops and a Paint the Stars workshop to go with our Night Sky Tours and Sunday Guided Day Tours. We’ll also have our Open Day with of Intro To The Stars Festival on Sunday the 21st of January.

Thank you for being a part of the Perth Observatory community. Your enthusiasm for astronomy and exploration fuels our passion, and we can’t wait to share more celestial moments with you in the coming year.

Wishing you all a Happy New Year!

Matt Woods Editor

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The Helix Nebula

NGC 7293

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Upcoming Events 13th of January

14th of January

Nightscapes Workshop

Paint The Stars

Time: 1 pm - 10 pm Price: $230 per person

Time: 10:30 am - 2:30 pm Price: $110 per person

Unlock the secrets of nightscape photography and take your photography to new heights at the Perth Observatory. Led by the experts at Astro Photography Australia, this small-group workshop will give you hands-on experience with your own camera for widefield astrophotography.

Immerse yourself in a unique experience that combines creativity, exploration and delicious food. Join us and unleash your artistic talents whilst recreating your own Van Gogh’s iconic “Starry Night” scene with Artist Karin Duarte from Fusion Cre8tive. We will provide a delicious grazing board lunch, tea and coffee.

Discover what your equipment is capable of and how to get the most out of it.

The event will end with a guided tour of our historic Observatory and Museum.

24th of January

4th of February

Lunar Photography Workshop

Black Cockatoo Kids Painting Workshop

Time: 7 pm - 10 pm Price: $120 per person

Time: 9:30 am - 10:30 am and 11 am – 12 pm Price: $40 per child

This promises to be a fun relaxed evening of photographing the Moon on some fantastic telescopes using your camera.

Join West Aussie Artist Hayley Savage at where she will teach you step by step how to create this funky Black Cockatoo painting.

This workshop is aimed at children between the ages of 7 - 11. Inspiration for this workshop has been driven by our fantastic location in the Korung National Park east of Perth where we are visited by an abundance of wildlife including families of Black Cockatoos.

Using a combination of Astrophotography Australia telescope and equipment, and the Perth Observatory telescopes, to take awesome photographs of the moon, and at much higher magnification.

Blossoming Banksia Painting Workshop

Valentine’s Night Tour

Time: 1:15 pm - 5 pm Price: $110 per person

Time: 8:30 pm - 10 pm Price: $55 per adult and $25 per concession

Join West Aussie Artist Hayley Savage for an afternoon where she will teach you step by step how to create a beautiful blossoming banksia painting.

Love is in the air at the Observatory. book on our special night sky tour so you can spoil that special someone in your life. Our Volunteers will take you on a grand tour of the Southern Hemisphere’s sky

The afternoon will start with a guided tour of our Observatory and then the painting workshop. We’ll provide a delicious grazing platter to nibble on whilst you paint. Feel free to bring your own drinks, and rest assured that tea and coffee will be readily available to keep your creative energy flowing.

The observatory will be open earlier as well so you can have a lovely picnic dinner on our back lawn with the kangaroos.

24th of February

28th of February

Hills Symphony Orchestra Sci-Fi Concert

Astronomy 101 Course

Time: From 6 pm Price: $70 per family (2 Adults And 2 Children), $30 per adult, $20 per oncession, and $10 per child (Ages 5 to 17)

Time: 7 pm - 8:30 pm (Doors open at 6:30 pm) Price: $300 per person

Prepare for an extraordinary musical journey as the Hills Symphony Orchestra takes you on a cosmic adventure with a Sci-Fi Concert set against the breathtaking backdrop of the Perth Observatory’s Domes and bush setting.

Immerse yourself in the magical world of science fiction as we blend the artistry of live orchestral music with the wonders of the universe.

Are you fascinated by the vast expanse of space and the mysteries of our universe, but never found the time to learn about it? Well, now is the perfect opportunity to discover more about our amazing cosmos!

Perth Observatory has a 5-week introductory course on space and astronomy, covering a range of topics. Led by our experienced STEM Coordinator, Jenny Gull, you’ll have the chance to learn from an expert in the field.

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14th of February

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4th of February

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Photographing Meteor Showers

By Roger Groom

Meteor showers can last for weeks and the best night to photograph them is during the peak night. Timeanddate.com has a great section for meteor showers with info tailored for your location on when these meteor showers and their peak nights will occur, and an interactive map of the night sky to show you what time to go out.

What if I can’t view them on the peak night you say? Well, these meteor showers come and go over time, so you will likely see meteors on nights either side, with the rate decreasing night by night. There’s no harm in giving it a try on other nights, or even doing a practice run in the nights leading up to the peak night.

Meteors can appear anywhere in the sky but but generally speaking, point your camera towards the constellation of the meteor shower is named after. Mobile apps like Stellarium and Sky Safari can help you with this. Until the constellation is above the ground, the chances are a reasonable proportion of the meteors simply won’t be above the ground either, or so your chances of seeing one is reduced until the constellation has risen higher in the sky.

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Meteor showers are caused by streams of cosmic debris called meteoroids entering Earth’s atmosphere at extremely high speeds on parallel trajectories. Most meteors are smaller than a grain of sand, so almost all of them disintegrate and never hit the Earth’s surface. They occur at specific times each year when Earth passes through streams of these meteoroids that are left over from tails of specific comets. It’s like driving down a freeway and encountering a rain shower. At the start and at the end, you will only see a few rain droplets, but it is in the middle of the shower where you encounter the most rain droplets.

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The 2023 Geminids Meteor Shower peaked overnight on Thursday the 14th of December.

The Geminids is typically our most consistently performing meteor shower to observe here in WA. There are 11 other annual meteor showers and plenty of minor meteor showers that occur throughout the year.

PAGE 11 Image Credit: Roger Groom

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Observing a meteor shower is not something you do by simply ducking outside for 20 minutes.

Even if the Zenith Hourly Rate (ZHR) is high, you will still need to be outside looking up (or photographing) for a decent period to have a chance of seeing/photographing any meteors.

 Let your eyes adjust over a minimum of 20 minutes.  Use a head torch with dimmable light and use low level white light or red light when moving around outside or using your camera, so you have more chance of seeing a meteor.

 You need to be observing the night sky for a good few hours if you are going to capture (or see) any decent number of meteors.

 If you tire of being outside, set your camera up and leave it taking exposures over a long

period of time, many hours if you can, while you go back inside or to sleep. Cable release/ intervalometers, or internal camera intervalometer, and possibly an external power source such as USB power brick powering the camera by USB-C can allow this.

Image Credit: Roger Groom

Photographing a meteor shower with your mobile phone is a tough ask, I’ll be honest! You will probably only capture the brightest of meteors.

Most modern mobile phones are capable of some nightscape/Milky Way astrophotography. They do this using along exposure time, usually of about 10 seconds. Meteor showers present a particular challenge where the camera needs to capture a brief burst of light very quickly. This is difficult for mobile phones.

The algorithms used for mobile phone astrophotography typically “accumulate” the image over time and perform some smarts to smooth out noise and combine the accumulated images. This means that small brief changes like a flash in the sky might or might not, depending on your phone, be represented in a final image.

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To give your mobile phone the best chance of recording a meteor:

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 Mount the mobile phone on a tripod. Manufacturers such as Leofoto have tripod mounts 

for mobile phones.

Turn off the flash

 Use a pro app to do interval shooting:  Allowing you to take a continuous sequence of photographs one after the other for a 

long period of time (hours ideally, but as long as you have).

Each exposure would be about 10-15 seconds ideally.

 No gap between exposures.  Use a long exposure time (if able to configure this in your app) such as 10 seconds. The longest exposure time you are likely to want is 15 seconds.

 Use a external USB battery to power your phone for a longer period of time.  Do a test run beforehand with the Timelapse function on your phone camera. If it will take

long exposures during the timelapse then it may be useful, but many will limit the exposure time to very short in this mode.

Photographing a meteor shower with a DLSR/Mirrorless camera is like nightscape astrophotography with a few critical differences:

 Ensure Long Exposure Noise Reduction is disabled in your camera, so it does not take a second exposure with the shutter closed (excluding Canon 6D which buffers the dark frame).

 Your camera needs to run over several hours. Use an external battery source and a large memory card, together with cable release or intervalometer to have continuous exposures.

Those are the main differences between a normal nightscape and a meteor shower session. Now I’ll go through the full set of settings I would use for a meteor shower photography using a DSLR or Mirrorless camera:

Lens:

 Use the fastest lens you have (smallest F number, such as F/1.8 or F/2.8).  Use a wide lens, such as 12mm, 14mm. Anything down to as narrow as 24mm is useful, but widest the better.

 Put the lens/camera in manual focus mode so it doesn’t focus hunt every exposure.  Put the lens shade on, to help keep dew/condensation off the lens.

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Camera:

 ISO 1600 – 3200 is a general good starting point, depending on many factors unique to your 

situation, but check your images for noise and decrease ISO if too noisy.

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Shutter speed: Generally, up to 15s (see notes below).

 White balance: AWB or fix it on something such as 4500k for consistency.  Long Exposure Noise Reduction: Off  High ISO Noise Reduction: Low or off  Drive mode: Continuous (low or high speed) Accessories:

 Use a Remote trigger, cable release, intervalometer or such to ensure continuous ongoing exposures one after the other.

 Use a Dew heater/strap if in a moist environment prone to condensation.  Use a USB battery pack to power your camera (if compatible).

Here’s how you go about it:

1.

Let your eyes adjust and get to know your camera in the dark.

2.

Connect your camera onto a sturdy tripod.

3.

Configure the settings on the camera.

4.

Focus manually on a bright star/planet using Live View. Some modern cameras will autofocus on stars in which case do this, and then switch to manual focus.

5.

Do a test run on short (5s) exposures to check focus and composition.

6.

Then set the camera to a longer exposure time such as 10 or 15 seconds.

7.

Use your intervalometer, cable release or other mechanism to take continuous exposures.

A note on shutter speed:

 A longer shutter speed (15s, maybe 30s) will mean less images to process/store and show a brighter night sky in each individual exposure.

 A shorter shutter speed (5s – 10s) will mean you can use the exposures to build a timelapse video with smoother transition, as well as use the exposures in their own right as individual photos. The individual exposures will not show the night sky as bright, but the decrease in shutter speed won’t affect how bright the momentary meteors are in your images.

 Your camera and lens combination, and where you are pointing your camera in the sky will

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Enjoy the night!

2023 SUMMER EDITION

dictate what the longest shutter speed is you can do before stars trail. The 500 rule is a guide (500 divided by your lens’s 35mm equivalent focal length) but doesn’t cater for all this.

Do some test shots and check your playback.

I find it hard to stop the technical work at the camera and actually enjoy the experience of being under the stars and seeing meteors in person, but we should try! As dedicated as we may be to the cause of astrophotography.

To be prepared for future meteor showers you should jump on one of my workshops where I teach astrophotography.

Image Credit: Roge Groom

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Sunday Guided Day Tours

Discover the secrets of the universe and the rich history of Perth Observatory on our Sunday guided day tours!

Nestled in the stunning bush settings of Bickley, our Observatory is the perfect place to explore the wonders of the cosmos.

Our knowledgeable guides will take you on a journey through time, from the Observatory’s humble beginnings in 1896 to its move to Bickley in 1966 and beyond. You’ll get to tour the Meridian, Astrograph & Calver Telescopes, learn about timekeeping, and explore the museum to discover fascinating stories about the Observatory’s past and present.

I the weather permits, you’ll have the opportunity to safely observe the Sun and its sunspots. It’s an experience you won’t want to miss!

There is no need to book, simply come up between 1 and 4 pm and pay in our shop. Our Sunday day tours are the perfect way to spend a relaxing afternoon with family and friends, surrounded by the beauty of nature and the mysteries of the universe.

By Louise Kaestner

How do I know all this if I wasn’t conscious before I was born? Well, I have plenty of brothers and sisters. Oh, sure, what those creatures on that planet see is bright dots of light. They stare at us with long thin things that capture the light we emit.

We pick up their thoughts, with our light, and communicate back. But they can’t hear us. Is it something about their wavelength or the way they come into existence?

Anyway, my brothers and sisters, the ones who came before me, tell me how beautiful it was to watch my birth. It also reminds them of how they came into being.

We pass this knowledge down from one to the next and to each other once we realise ourselves.

Do you want to know the difference between boys and girls? Boys tend to get only as a large as my brother, those sentient life forms call the Sun. He is the closest of us to that planet. Girls get way bigger. That’s because we transform at the end of our lives. Some of the leftovers from this event returns to the womb to influence new births.

There is an intense heat burning within from the food I’ve eaten since birth. The food I digest creates other food for me to digest. It isn’t food according to the life that believes it has the only sentience in the cosmos, but it’s food for me. After all, it nourishes me and keeps me alive. Is that not what food is?

In the beginning my food was very light and thin. Delicious. I would eat more and more of this. Never would I stop. Bigger and bigger I got. Finally, I ran out of my favourite food. That was okay. There was a new one. This time the food was a little heavier. I ate and ate until that was gone. That was fine, because, again, I had another new food to eat, which was heavier than before.

There isn’t much time left. I have gotten very heavy and hot. I’ve run out of food and there is nowhere for me to get any other. In the distance the minds of the sentient life get so excited every time the look at me. I don’t understand why they feel this way. It’s only natural, what is happening. I’ve been around for so long, accumulated so much material, and it is time for me to evolve. I eat the last morsel of my heaviest food.

And burp.

NEVER THE END

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I remember my birth from a long time ago. Was it a birth according to the terms of the smaller, sentient life forms which stare up at me from their tiny planet? It was more of a creation, rather than birth. I have neither a mother, father, nor any sort of parentage. But I did start in a giant womb, comforting, and very cold. How I began was sort of a wispy beginning. First, there was a bit of what a so-called sentient life form would call dust and gas, then there was a process, a caving in. As this cloud fell into itself, things began to get warm.

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‘Sup, er, Nova?

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Star Adoption Tours

2023 SUMMER EDITION

Looking for a unique gift to recognise a special family member or friend? Look no further than our star adoption program! Our program allows you to adopt a star between magnitudes -1 and 7.9 in the Southern Hemisphere, visible to the naked eye or in binoculars.

Each star adoption package includes a certificate with the star’s name and coordinates, as well as the duration and purpose of the adoption. Plus, you and up to three guests can enjoy a private star viewing night within 12 months of the adoption, where you’ll get to see your chosen star and other seasonal objects.

We’ll also provide you with a planisphere and star charts, so you can continue to enjoy your star long after your viewing night.

Please note that while we don’t offer international naming rights for stars, the income from our program goes towards supporting the Perth Observatory’s not-for-profit public outreach program. Adopt a star today and give the gift of wonder and discovery!

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Image Credit: Ronny Kaplanian

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Helix Nebula

NGC 7293

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The Euclid

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Space Telescope Exploring The Dark Universe

By Paul Fisher When I was at school (more years ago than I like to remember), Euclid was the guy who invented all those geometrical theorems we had to memorise.

Now there is a new Euclid – a space telescope operated by the European Space Agency (ESA).

Fittingly, this new Euclid will map the underlying geometry of the Universe, providing answers to some of the deepest mysteries of cosmology.

Despite his overwhelming influence on mathematics, very little is known about the real Euclid. He was likely born in mainland Greece but worked and studied in Alexandria about 300 BC. His best-known work is Elements, a 13-volume treatise on mathematics, number theory, plane geometry and much else.

Much of Euclid’s work has been lost, but there is one surviving document of great importance – the Phaenomena, on the theory and practice of spherical astronomy.

Our universe is not as it seems. The galaxies, stars, gas, and dust we can see make up only about five percent of the total mass and energy of the universe. An unseen substance – dark matter – contributes another 26% and is responsible for the clustering of galaxies and their rotation.

But the universe is expanding at an accelerating rate. Herein lies one of the current major problems of cosmology – depending on how it’s measured, the rate of expansion gives very inconsistent results – the so-called Hubble Tension. An unknown force – dark energy – is causing the acceleration and makes up the remaining 69% of the mass / energy budget.

Current thinking is that dark energy becomes dominant as the average density of the universe decreases due to its expansion.

Image Credit: ESA/Euclid/Euclid Consortium/NASA; J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi; CC BY-SA 3.0 IGO

Image Credit: European Space Agency

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Image Credit: ESA/Euclid/Euclid Consortium/NASA; J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi; CC BY-SA 3.0 IGO

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Dark energy played an insignificant role in the very early universe but started to make its presence felt about 10 billion years ago.

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The real nature of dark matter and dark energy are unknown. Dark matter cannot be explained by the standard model of particle physics, and dark energy cannot be reconciled with quantum theory. This is where the Euclid mission comes in.

Euclid is an ESA mission to map the geometry of the dark Universe. The mission will investigate the distance-redshift relationship and the evolution of cosmic structures. It achieves this by measuring shapes and redshifts of galaxies and clusters of galaxies out to redshifts 2, or equivalently to a look-back time of 10 billion years. It will therefore cover the entire period over which dark energy played a significant role in accelerating the expansion.

Euclid is a space telescope that will image billions of galaxies out to 10 billion light years across more than a third of the sky. This will allow astronomers to measure the expansion history of the Universe and the growth rate of cosmic structures. These measurements will, in turn, provide a detailed characterisation of dark matter and dark energy, and will test General Relativity on cosmic scales.

The Euclid mission involves a comprehensive sky survey covering an area of 15,000 square degrees—roughly one-third of the entire sky. This extensive coverage is vital for obtaining statistically significant data on the distribution of galaxies and galaxy clusters. The telescope will observe two primary cosmological probes: weak gravitational lensing and baryon acoustic oscillations.

Weak gravitational lensing involves the subtle distortion of background galaxies’ shapes by the gravitational influence of foreground matter. By analysing these distortions, astronomers can infer the distribution of dark matter and dark energy in the universe. Baryon acoustic oscillations, on the other hand, are periodic fluctuations in the density of visible matter that provide a standard ruler for measuring cosmic distances.

The spacecraft is about 4.7 m tall and 3.7 m wide. Euclid’s mass in orbit is about two tonnes (including 800 kg of payload module, an 850 kg service module, 40 kg of balancing mass and 210 kg of propellant).

The service module contains the satellite systems: electric power generation and distribution, attitude control, data processing electronics, propulsion, telecommand and telemetry, and thermal control.

Electric power is supplied by large solar panels which also act as a sun shield. The payload module includes the telescope, thermal control system, fine guidance sensor and the science instruments.

Euclid contains three primary science instruments:

 A 1.2 m diameter telescope.  A visible wavelength camera with resolution of over 600 megapixels; and  A 65 megapixel near-infrared camera / spectrometer.

Image Credit: European Space Agency

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Image Credit: European Space Agency

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Image Credit: ESA/Euclid/Euclid Consortium/NASA; J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi; CC BY-SA 3.0 IGO

Image Credit: European Space Agency

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Image Credit: ESA/Euclid/Euclid Consortium/NASA; J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi; CC BY-SA 3.0 IGO

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The telescope is a three-mirror Korsch design corrected for spherical aberration, coma, astigmatism, and field curvature and has a wide field of view (1.25 x 0.727 deg) while ensuring that there is little stray light in the focal plane.

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The visible wavelength camera enables ultra-high-resolution images and will be used (among other things) to measure the apparent distortion of galaxies caused by gravitational lensing.

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The spectrometer will allow highly precise measurement of the red shift of objects.

Euclid’s instruments will generate an enormous quantity of data, with an on-board storage of 2.6 Tb. Actual data throughput will be limited by the ground station at Cebreros in Spain. The spacecraft will communicate with Cebreros about four hours per day, transmitting 55 gigabits per second. Backup tracking and communications are provided by the ESA ground station at New Norcia.

Over the planned six-year project life, some 170 petabytes of raw input images will be downloaded, with data processing occurring in 100 laboratories spread across 18 countries.

The sensitivity of Euclid’s cameras requires extreme accuracy and stability of telescope pointing. The Attitude and Orbit Control System (AOCS) is a complex set of hardware and software components including star sensors, gyroscopes, cold gas thrusters and reaction wheels. Combined, the system allows for rapid orientation of the telescope and extremely stable pointing and tracking, at a rate of 35 milli-arcseconds per exposure.

The AOCS is so sensitive that it can compensate for tiny motions, such as those induced by the cameras’ filter wheels.

The Euclid space telescope was originally intended to launch on a Russian Soyuz rocket, but this plan was abandoned after the invasion of Ukraine. Euclid was eventually launched from Cape Canaveral on the 1st of July 2023, atop a SpaceX Falcon 9 rocket.

Euclid is in a halo orbit about the Sun / Earth L2 LaGrange point, roughly 1.5 million kilometres from Earth. It shares its orbit with the James Webb space telescope and Gaia.

Euclid’s first images were published in November 2023 and demonstrate the amazing image quality achievable with this telescope.

Euclid’s legacy extends beyond its primary mission timeline. The vast dataset it generates will serve as a valuable resource for the global astronomical community, enabling researchers to conduct a wide array of studies beyond the mission’s original scope. The Euclid archive, containing a wealth of information about the distribution of galaxies and the cosmic web, will be a treasure trove for astronomers seeking to explore various astrophysical phenomena.

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Telescopes Under

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Western Australia’s Skies

Looking for an unforgettable night under the stars? Look no further than Perth Observatory’s offsite astronomy nights! As Western Australia’s leading Observatory, our experienced volunteers are dedicated to sharing the beauty and wonder of the night sky with people across the state.

Our team will bring their top-of-the-line telescopes and expertise to your town, suburb, or school, providing you with a unique and immersive journey through the Southern Hemisphere’s celestial wonders. We will also guide you through the night sky with the help of our green lasers, teaching you about the stars, planets, nebulas, dying stars, and enormous star clusters that populate our universe.

Whether you are an astronomy enthusiast or simply looking for a fun and educational experience, our offsite astronomy nights are the perfect way to explore the beauty and complexity of our universe. Request your night under the stars below and discover the magic of Perth Observatory!

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Join our School � Day Tours Team Looking to volunteer and make a difference in the lives of primary school children? If you have free time during the day and a passion for learning about space and our solar system, we invite you to join our School Day Tours Team as a volunteer!

As a member of our team, you will have the opportunity to share your knowledge and enthusiasm with young students while learning from experienced educators. No prior experience is necessary, as we provide all the training you need.

If you enjoy working with children, this could be the perfect opportunity for you! All you need to bring is your enthusiasm, a friendly demeanour, and the ability to communicate with children.

To learn more about how you can get involved, click below and let’s start making a difference in the lives of young students today.

PAGE 27 2023 SUMMER EDITION Image Credit: NASA/JSC

Are We Fired?

By Amber Berriman Imagine, for a moment, you are the top in your field, chosen by NASA to become one of the few headed to the International Space Station (ISS). It’s the mission of the lifetime and you nervously sit in the spacecraft in a huge, heavy spacesuit not knowing what will happen.

Upon arriving safely, the initial nervousness transforms into a routine, the shock of the microgravity becomes easier to handle.

Eventually, the daily routine of exercise and work becomes an extremely complicated dance in which you stumble through.

Outside is always the gorgeous infinity of starlight and you gaze back home as you hurtle around it.

Then one day, you and your fellow teammate go on a spacewalk, the limitless expanse of space stretches out in every direction. You must make very deliberate moves, tethered to a station hurtling around the earth. It’s been an extremely long shift, the bearing of your spacesuit not helping your weary muscles.

Carrying a very important toolbox, needed for your mission to succeed, you try to pay attention to your co-worker story however you can barely focus. Your eyes go weary as she asks you to pass her the toolbox, you go to do so but panic rises, you watch helplessly as the toolbox slowly slips out of your hands.

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A few choice words flow into your mind as you turn to your team-mate who uselessly watches the toolbox fly away. In the silence you must ask one single question, “Are we fired?”

This was the reality (with a bit of creative tweaking) for two of the International Space Station employees, Jasmin Moghbeli and Loral O’Hara. On the 1st of November 2023, the two teammates embarked on a sevenhour spacewalk to repair a solar panel on the stations exterior but lost grip on the $100,000 toolbox. Remarkably, this toolbox boasts a magnitude of +6, meaning it can be seen with binoculars. Its location has been verified by their Japanese colleague, Satoshi Furukawa, who discovered he’d accidentally taken a photo of it when capturing an image of Mount Fiji during the ISS fly over of his homeland.

Thankfully the toolbox poses no imminent threat and will remain observable for the next few months until it will enter the Earth’s atmosphere and will incinerate.

Wondering how will you be able to see this mysterious toolbox? First step would be to grab your trusty pair of binoculars. Currently, it is positioned around 5-10 minutes ahead of the ISS. Using the ISS tracker or Heavens Above, you can determine when and where the ISS will be flying past you.

Image Credit: NASA TV

You reach for it, but the restriction of your spacesuit limits you as you watch it hurtle away.

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REMOTE CITIZEN SCIENCE FROM PERTH OBSERVATORY

By Brad Young

APERTURE: FOCAL LENGTH: F-RATIO: FILTERS: CCD SIZE: FOV: SITE:

0.4 m 2011 mm 5.7 g’, r’, i’, U, B, V, R, Clear, Ic, SPEC200 grating 1600 x 1200 (7 mega pixels) 20.2 x 15.2 arcmins Perth Observatory

A great deal of the work that I do using the R-COP telescope at Perth Observatory is observations of variable stars and minor planets. Using this scope, I have been able to report on many overlooked variable stars in the southern hemisphere. There are also often minor planets that come to opposition in the far southern skies that may be difficult or impossible to see from northern latitudes. With this telescope I can perform astrometry and photometry on these targets and fill the gap.

Astrometry is the precise determination of position of an object that moves, for instance a minor planet. Photometry is the measurement of the brightness of an object. Photometry is usually performed because it is variable such as a variable star or differences in brightness due to the rotation of a minor planet.

For variable stars, often the type of variable, and perhaps even its period and luminosity curve are known. However, any changes or evolution that might occur will not be noticed if they are not observed in a regular fashion. There is usually a recommended cadence or time allowed between observations associated with variable stars. It may be as little as an hour for certain types, or several days for long period variables that change very slowly. The variable stars that I track are representative of the many types and categories of variables and have cadences from a few hours to a week or so.

2 light curves generated using recent observations with R-COP. All by me except those denoted with a cross. V0600 Carinae is a Mira type long period variable. PKS 2005-489 is a BL Lacerta object (extragalactic QSO)

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The R-COP telescope is equipped with a Paramount ME telescope mount, a Celestron C14 optical tube, and an SBIG ST-10XME astronomy camera. R-COP Technical Specifications:

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A few years ago, I began using the online observatory service called Skynet to access the 20 m radio telescope at the National Radio Astronomy Observatory (NRAO), Green Bank, West Virginia, in support of an AL Observing Program. While involved with that project, I was invited to also observe remotely using the Remote Telescope Partnership, Clarion University – Science in Motion, Oil Region Astronomical Society, and Perth Observatory (R-COP) telescope in Perth Western Australia. The optical system at Perth is part of a world class observatory, and for a citizen scientist like me, this provides a powerful tool to observe in the southern hemisphere, which due to geography, is still underrepresented by amateur astronomers.

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Another exciting opportunity occurs when the American Association of Variable Star Observers (AAVSO) sends out a request for observations in support of a science mission. These may involve terrestrial telescopes, or they may be run from orbiting observatories such as Hubble Space Telescope (HST) or Transiting Exoplanet Survey Satellite (TESS). One alert was for continuing observations of PNV J17224490-4137160, a bright nova in Scorpius discovered by Australian amateur Andrew Pearce. The bulletin is disseminated via email and provides pertinent data on the star involved, the cadence, the filters to be used, and the period from beginning to end of the subject project.

No Near-Earth Object (NEO) surveys are run in Perth, but there is much support work to do in both this field and in preparation for the landing, excavation, and exploration of minor planets that is ongoing. I was able to assist the Origins Spectral Interpretation Resource Identification Security - Regolith Explorer (OSIRIS-Rex) project in its visit to extensively map 101955 Bennu and collect samples to return to Earth. Bennu has the highest cumulative rating on the Palermo 10 Hygeia April 12 2023 – motion and change in brightness in one night. Image Credit: Brad Young Technical Impact Hazard Scale of any NEO, at a cumulative 1-in-1,800 chance of impacting Earth between 2178 and 2290 with the greatest risk being on the 24th September 2182.

Other asteroid work has centered on astrometry and photometry of other carbonaceous objects like Bennu, to give researchers more information and perhaps select targets for other missions. I also image minor planets at particularly close approaches, as often these objects may go years between close study. Another way to add to science is to determine through photometry the rotational period of the asteroid about its axis.

Artificial satellites are also a part of my observing program at Perth. Most move much too fast for its narrow, highly magnified field; R-COP is not set up for such work.

However, some spacecraft, such as the James Webb Space Telescope (JWST) were visible on the way to final orbit. The booster rockets are not followed with telemetry, and it is useful to see what the initial placement is for the rockets and debris. These items are often confused later with new asteroids and need to be tracked to clear up their identification without wasting observatory or radar time on them. Other spacecraft revisit the Earth occasionally for a gravity boost to conserve fuel needed to reach other planets or asteroids. These can be seen on flybys and can be watched for any unusual orbit changes or evidence of control issues.

I have not yet taken the big step into the search for exoplanets, which depends on very accurate and precise photometry, but it is on the horizon as another use for the R-COP telescope. It is, however, very time and resource intensive, and would tie up this shared system during the exposures.

Comet 364P PANSTARRS on May 27 2023. Image Credit: Brad Young

Image Credit: Roger Groom

Citizen science has become an integral part of the human quest for knowledge. Amateurs have always been a crucial part of astronomy, and now with so much to observe, and the tangible rewards available from exploration, it is even more important. Tools like R-COP and the support of the Perth Observatory staff allow me to provide real scientific data, using premier instruments.

Instead of having objects fall between the cracks, I can help keep a vigilant eye on our universe.

It’s important, and, for me, it’s rewarding.

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Both photometry and astrometry also provide useful comet data, although I have only rarely tried this challenging work. Again, due to geography, some comets are much better placed for the southern observer. For transient objects like comets, foul weather in the north can also interfere with gathering as many observations as possible while the object is still nearby or bright.

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At some point, when I am sure I can effectively use the scope and not exclude other users too much, I may try this cutting-edge science for amateur citizen scientists.

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Cosmic Treasures The Marvels of Meteorites

By Beryl Keaughran Meteors are a constant reminder of what’s happening in our solar system and beyond.

When we see them shoot through our sky we look with excitement and awe at the majestical colours and light.

While in space, they’re called a meteoroid and as they enter our atmosphere that name is changed to a meteor. It isn’t until they hit the ground that their name is changed to a meteorite.

There are three kinds of meteorites. The majority of meteorites that hit the Earth are made up of stone.

Iron meteorites are rare and make up 4% of the meteorites that have hit the Earth, and we have one on display in our museum. To be exact, our 189 kg piece of the Mundrabilla meteorite is made up of 93% iron and 7% nickel. Iron-stoney meteorites are even rarer with only 2% of the meteorites that have hit Earth being of this type. They are large asteroids that have melted its inside and forms many beautiful crystals that are called Pallasites. One owner in America, sold a large slice of an iron-stoney meteorites for $1.7 million. Here in Australia any meteorite found is the property of the WA Government, and you must let the WA Museum know if you find one.

Named after the Western Australian coastal town of Binningup, not far from Bunbury, two of the residents decided to sunbake on the beach. While lying there they heard a loud bang in the sky, they thought it was someone shooting, but next moment a streak of dazzling light passed overhead landing next to them covering them in sand. It was a meteorite. The loud noise was the meteorite going through the sound barrier, and it was heard as far away as Perth, some 130 km away.

In 1884, between York and Quairading there was a meteor and quite a few pieces of it landed near Quairading. The local constable from the police outpost of Youndegin found a few pieces and he sent the people out searching for more it. It’s said that the local blacksmith found a piece which being Iron, he hammered into a horseshoe, and it hung in his shop for many years.

In 1911, the federal Australian government started to build the Trans-Australian Railway line across the Nullarbor Plain from the West coast to the East coast. There were many fragments of meteorites found especially on the Premier Downs station. In 1944, a rumour started that there was a meteorite the size of a car out on the Nullarbor. Expeditions were sent out to look for it, but they always came back empty handed.

Finally, in 1966, two geologists, called R.B. Wilson and A.M. Cooney found the rumoured fragment.

It was in two parts, the larger of the two pieces, weighed 12-tonnes and the other 5-tonnes. The 12-tonne piece went to the museum in Perth and the 5-tonne piece to Albany. After weighing all the fragments found in the area, it was calculated the actual asteroid would have weighed between 22 to 24 tonnes.

One theory why there was no crater to mark where it had impacted, was that a million years ago the Nullarbor Plain was an inland sea, and as the meteor was moving through the atmosphere it broke apart. This would explain why people find pieces of the Mundrabilla meteorite over a large area, and why they were found indented in the ground without making a crater.

Near Shark Bay, is the Woodleigh crater. When this meteorite impacted the ground, it hit with such force, the zircons inside, heated up and turned into a very rare mineral called Reidite, which is heat resistant and very strong.

With some of the oldest crust on Earth, Western Australia is a fantastic place to study impact craters and meteorites. There are 30 known craters in Western Australia, and the best way to understand the impact of meteorites is to go there and study not only the rocks but the shape of the craters as well.

Image Credit & Copyright: Tanatpon Chaweewat

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They could be large when being pulled into earth’s gravitational pull but their journey through our atmosphere burns them up and can be the size of a small potato when landing, such is the case of the 1984 Binningup meteorite.

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Meteorites have hidden treasures. Inside, meteorite hunters have found gold, diamonds, zircons, and even rubies. The rubies were found by Japanese scientists who performed a trial-run at exploding an asteroid.

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Saturn’s Bling on the Edge

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Saturn’s Edge-on Elegance Takes Centre Stage In 2025

By Rashel Jahan Witnessing Saturn’s famous rings from Earth is poised to become a challenging endeavour in the upcoming years. There is approximately a year and a half left to catch a glimpse of Saturn’s renowned rings. Afterward, in 2025, Saturn’s alignment will render its rings as an incredibly thin line, almost imperceptible from Earth.

Saturn’s rings, though expansive, with segments spanning an impressive 70,000 to 140,000 km in width, are surprisingly slender, measuring only about 10 meters in height within the main rings.

Their visibility is diminishing due to Saturn’s changing position, so it’s advisable to observe them while the opportunity still exists.

The silver lining is that the rings won’t be hidden forever. They will gradually realign with Earth as Saturn continues its 29-year journey around the Sun. Saturn’s orbit exhibits a subtle wobble, causing the planet to incline toward and away from the Sun during its orbital path. This phenomenon leads to a unique event occurring roughly every 13.7 to 15.7 years, providing Earth a lateral view of Saturn. During this period, its rings appear to disappear from our vantage point.

Currently, Saturn’s majestic rings grace our view with a tilt of 9 degrees toward Earth. However, by the year 2024, this angle will diminish to a mere 3.7 degrees. This rare occurrence last unfolded in September 2009, with the previous instance dating back to February 1996. Astronomers will need to exercise patience, as the next chance to witness Saturn from this distinctive perspective won’t arise until October 2038.

While Earth’s passage through this edge-on view might render Saturn’s rings nearly indistinguishable, it offers an exciting opportunity for astronomers to focus their attention on some of the planet’s 146 moons.

Following this edge-on view, Saturn’s rings will swiftly resurface as the planet’s South Pole aligns itself with Earth. This alignment will unveil the underbelly of the rings, a sight that has remained hidden for over 15 years. The rings will progressively become more discernible until 2032 when Saturn reaches its maximum tilt away from Earth.

Saturn’s magnificent rings primarily consist of ice, rock, and dust particles ensnared by the planet’s gravitational influence. Among these particles, some are diminutive, no larger than grains of sand, while others attain sizes comparable to houses.

The prevalent theory suggests that Saturn’s rings originated from the remnants of a moon that succumbed to Saturn’s potent gravitational pull. Astronomers, however, debate their age, with differing viewpoints proposing that they could be as ancient as the solar system itself or relatively youthful.

PAGE 36 2023 SUMMER EDITION Saturn’s rings Changing. Image Credit: Alan Friedman

Saturn’s rings edge on. Image Credit: ESA/Hubble

Saturn’s Rings layouts. Image Credit: NASA/JPL

Despite the anticipated temporary disappearance of Saturn’s rings, scientists caution about the possibility of their permanent disappearance in the distant future. NASA’s Cassini probe, which made 22 passes through Saturn’s rings before its ultimate plunge into the planet in 2017, uncovered unsettling evidence of the rings’ dissipation at a rate that could be deemed catastrophic. According to the findings from the Cassini probe, Saturn’s rings were losing mass at a substantial pace, estimated to be somewhere between 400 kilograms and 2,800 kilograms every second.

Dr. James O’Donoghue, a planetary scientist at the Japan Aerospace Exploration Agency (JAXA), remarked, “We’re still trying to figure out exactly how fast they are eroding.” This mass loss is attributed to a phenomenon called ‘ring rain.’

Here’s the mechanics of it: Solar radiation endows particles in Saturn’s rings with an electrical charge. Consequently, these charged particles interact with the gas in Saturn’s atmosphere and are subsequently drawn out of the rings by the planet’s gravitational pull. Dr. O’Donoghue further highlighted ongoing research suggesting that Saturn’s rings may only remain integrated with the planet for a few hundred million more years.

The persistent process of erosion and the ultimate destiny of Saturn’s iconic rings remain captivating subjects for scientific inquiry.

So, do yourself a favour and find a friend with a telescope or visit an Observatory in your state to have a final glimpse of the rings for a few years.

Image Credit & Copyright: Ciclops

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The Perth Observatory’s Role In Implementing Standard Time In Western Australia

By Paul Jones

Now that we have access to time that is correct to the second, and readily available through our phones, it is hard to imagine a time when the absence of generally available accurate time was a significant impediment to productivity and a bug bear of the citizenry. However, that was the situation throughout the world up to the late 1880s when the problems local time was causing to commerce and travel became so large that the desire for action became overwhelming.

An international conference, convened by the President of the USA, was held in Washington in 1884, which resolved:

1.

That the prime meridian from which to reckon longitude should be the meridian of Greenwich, and that this should be adopted by all nations.

2.

That one time should be kept throughout the world— namely, Greenwich Mean Time.

3.

That it should be 0 hours, or midnight, at Greenwich when the sun transited the

4.

Anti-prime meridian.

5.

That the hours from midnight to midnight should be numbered by the numerals 0 to 24 consecutively.

This system was adopted, and the circumference of the globe was divided into 24 sections, or hour zones. The central line of each zone is an hour meridian, and the zones therefore theoretically comprise 15 deg. of longitude. The efficient working of the system did not require the boundaries of the zones to be sharply defined. Where necessary, they would be governed by national, geographical, and commercial circumstances. However, the cardinal principle was that the time in each zone should differ from the time in the next by one whole hour, and not by any fraction thereof.

Thus, throughout the whole world, the minutes and seconds would be everywhere the same, time only differing in the different zones by whole hours.

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A Correct Time For All

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In the colony of Western Australia, the Premier John Forrest, sort to establish the means to keep accurate time by proposing the building of an observatory. In his budget speech in January 1892 Forrest said:

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Another item you will find on the Estimates, and which as we progress and do not wish to be left behind in the race, is very necessary and important, and that is a Perth Observatory, for which £2000 are put on the Estimates. It is quite a reproach to this large colony that we have not an Observatory in it. Why, any of the small places about the world, if of any importance, has an Observatory, and this is especially noticeable in the other colonies of Australia, which are Observatories wherein astronomical and meteorological observations are registered, and by means of which ships in port can get their chronometers set by a time-ball. It is a discredit that there is not a time-ball at Fremantle, and that the shipmasters are not able to correct their chronometers except by a rough method of calculation.

However, his pleas fell on deaf ears and the parliament did not approve the £2000.

Australia moved on the adoption of the hour zone system, commonly called ‘standard time’, when an intercolonial conference was held in Melbourne in September 1892 to, inter alia, discuss the adoption of the hour zone system of reckoning time and the twenty-four-hour notation of the day.

The frustration with the absence of correct time is illustrated by an article in the “News and Notes” section of the West Australian, Wednesday 30th May 1894, which champions Premier Forrest’s desire for an Observatory to bring some accuracy to time keeping and surveying:

Among the uses of the Observatory, will be the very important one of giving correct time for Perth. At the present time, hardly any two of the public clocks in Perth correspond, and the Town Hall is the most erratic one of all. It appears that, every week, it varies two or three minutes, and apparently, it is only corrected at rare intervals, probably once a week. The result is that when it gains or loses a couple of minutes, and it is put back or forward, every watch or clock is incorrect. This is a serious matter for those who depend upon their time pieces to catch the trains. The usual custom in other places is to regulate the clock daily, and in some places, by mechanical means, hourly. This matter urgently needs to be taken in hand, pending the erection of an Observatory, which will, no doubt, be connected with the public clock in Perth, and keep one true time for all.

Forrest did eventually make headway on his quest for accurate time by getting the Standard Time Act passed on 17th July 1895, which established longitude 120 degrees as the meridian on which Western Standard Time (WST) is marked. Forrest was also able to get funding to build the Observatory in the 1895/96 and the 1896/97 budgets and work commenced in mid-1896, with the foundation stone laid in September 1896.

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The 1895 WA Standard Time Act

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In the summer of 1894/95, with the commitment to go ahead with the building of an observatory, Premier Forrest, on the way to the Premiers conference in Hobart, stopped off in Adelaide and requested the South Australian Government Astronomer, Charles Todd, provide advice on the establishment of an Observatory in Perth. Todd subsequently visited Perth and on his advice:

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 The Observatory was located on Mount Eliza at the entrance to Kings Park,  The transit circle telescope was ordered from Troughton and Sims in the UK.  The Astrographic telescope and a dome were ordered from Grubb in Ireland.  The Kulberg long-case astronomical regulators (clocks) were ordered from the UK.  The assistant at the Adelaide Observatory, W. E. Cooke, was appointed WA Government Astronomer.

Cooke took up his position of WA Government Astronomer in February 1896 and immediately went on a study tour of observatories in Europe, including visiting the workshops making the instruments for Perth.

Cooke returned to Perth in October 1896 and in the absence of the ordered meridian circle telescope and the Kullberg clocks, set about establishing correct time with a borrowed 5-inch Transit Theodolite with which he observed and timed the transit of the selected “clock” stars, and two marine chronometers, one to keep sidereal time and one to keep meantime, or WST. Initially the meantime chronometer was carried to the GPO to correct their clock but later it was connected to the GPO by electric cable and the update was done automatically.

The first correct time was passed to the GPO on 21st December 1896. Cooke describe this process in a letter to the West Australian in June 1898:

I commenced to observe for time with a theodolite long before the Observatory was built and have continued my observations with a small portable transit kindly lent me by the Surveyor-General, and which at present is the only astronomical instrument mounted. For a long time, past I have been giving exact time daily (10 a.m.) to the Railway Department. I have taken charge of a chronometer in the chief operating room in the Perth telegraph office, rating it systematically in order that the chief operator may wire exact noon throughout the colony daily. I give time signals as often as asked for (about twice a week) to the Watchmakers Company of Western Australia, who are responsible for the Town Hall clock, and the Fremantle office gives time to Hooper and Co. as frequently as telephonic arrangements will permit in order that the Fremantle town clock may be regulated.

Cooke went on to say:

The mean time clock (Kullberg) is only just released from the Greenwich Observatory and is now on the water. This baby Department has done as much in the way of establishing true time as could be done by the best-equipped observatory in the world.

I should like to point out, in conclusion, that the distribution of time is never part of the work of an observatory but must be accomplished by the Departments concerned.

Any attempt on my part in this direction would lead to an endless disorganisation.

Kullberg Chronometer in case. Image Credit: Paul Jones

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Poole Chronometer. Image Credit: Paul Jones

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A visit to the Perth Observatory Museum will enable you to see on display the 5-inch transit theodolite and the two marine chronometers used in the first accurate keeping and distribution of WST.

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During 1898, the sidereal and mean time Kullberg clocks arrived from the UK and took over the keeping of sidereal and mean time from the chronometers.

The Kullberg clocks served as the State’s principal timekeepers for over 50 years, until replaced in the late 1950s for one and early 1960s for the other, by the Shortt-Synchronome clocks. The mean time and sidereal Kullberg clocks have been restored and are on working display in the Perth Observatory Museum.

In June 1899, Cooke mounted a clock outside the gates of the Perth Observatory just opposite the entrance to Kings Park so that the public could get accurate time. The event was reported in the West Australian, which drew attention to how the clock was kept accurate using what is termed a Lund controller:

The clock is electrically connected with the standard clock at the Observatory, which automatically transmits a signal every hour A close inspection will reveal the presence of two pins, projecting from the dial on either side of the figure twelve When the signal comes from the standard clock, these two pins approach one another and adjust the large hand exactly to the minute It will then be seen that the time shown by this clock will never be more than a few seconds in error. Those who wish to have true time with the greatest possible accuracy may obtain it by waiting for the sudden movement of the pins, which will occur exactly at the hour.

The probable clock that was mounted at the gates of the Observatory for the public to see.

The slot for the pins of the Lund controller is the banana shaped slot at the top of the XII. The reverse view of the clock shows the solenoids that operated the pins for the Lund controller and the electrical connections. A clock was also mounted on the outside wall of the Observatory by the front door, which also had a Lund controller. The clock at the front door is believed to be the Benson clock, which has been restored and is on working display in the Perth Observatory Museum. Cooke, in his letter of 1898, also noted:

I have obtained copies of plans of the time-ball tower at the Semaphore, Adelaide, and discussed them with the Works Department, in order that they may be adapted for a time-ball at Fremantle, and the Department is now preparing plans to be submitted to me before sending them on for Ministerial approval. In addition, correspondence has passed through the hands of the late Minister of Education between the Commandant and myself with respect to the loan of an old-fashioned muzzle-loading gun whereby I might give a daily time signal to the inhabitants of Perth.

The time ball at Arthurs Head Fremantle was built and came into operation on 12th November 1900. After some difficulties with cost, a suitable cannon was purchased for £3 in November 1902 and the inhabitants of Perth heard the first retort at exactly 1pm on 16th November 1902.

The Perth Observatory was established in 1896 for the purely functional reasons of correct time, correct surveying, weather forecasting and tide forecasting that a rapidly developing colony demanded. Accurate WST was established in December 1896 and by 1900 when the meridian telescope and Kullberg clocks had arrived and been installed the observatory had a sophisticated

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system of keeping and distributing correct time, which remained largely unchanged until 20th August 1917 when the first time-signal was broadcast from the Applecross wireless station.

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Kullberg Meantime Clock. Image Credit: Paul Jones

Kullberg Sidereal Time Clock. Image Credit: Paul Jones

The probable clock that was mounted at the gates of the Observatory for the public to see. Image Credit: Paul Jones

Benson clock mounted at the front door of the Perth Observatory.

Image Credit: Paul Jones

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Image Credit: Roger Groom

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Geminids Meteors

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Perth Observatory Night Cameras

Perth Observatory is a member of the Global Meteor Network, and we now have seven cameras recording the night sky. These state-of-the-art cameras capture meteors, satellite passes, and other celestial events, providing us with a unique view of the Solar System’s formation and evolution.

The footage captured by these cameras is not only valuable for scientific research but also for public viewing. You can watch live images from the cameras at night, which update every three minutes during the night. Additionally, we’ve made available condensed footage from the previous night, highlighting every meteor detection. Be warned, it’s hard not to get hooked on watching these videos.

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Time-Traveling Artistry An Exclusive Interview with Perth Obversatory Volunteer Matt Repacholi

By Matt Woods

Matt Repacholi, is a volunteer at the Perth Observatory, and a craftsman with a passion for Dr Who. In our interview, we delve into the fascinating endeavor of building a faithful replicator of the Tardis console—an iconic centerpiece that adorned the Doctor Who night tour at the Observatory.

replicating physical objects from any book, show or film I enjoyed. It brings me a sense of joy to interact with something that originates in fiction, or even reality. It’s magic, and to bring other people that same of that magic and escapism is special to me.

MW: Are you a Doctor Who fan, and if so, what aspects of the TARDIS control console drew you to recreate it?

MR: Absolutely! I’m in love with the show.

There are endless stories that can be told when you’re talking about all of time and space as your setting. I think it was the fact this console is the first we see when the show was revived in 2005. It was an entirely practical set piece so I thought ‘If the BBC can do it, why can’t I?’. It also looks the most unique and ‘organic’ in my opinion.

MW: How did you approach the planning phase of the TARDIS control console?

MR: A lot of sketching, brainstorming, and

searching for good reference photos or material. Given it was from 2005, good quality photos were difficult to come by. I prototyped a few of the major parts early in the process to work out what worked and what didn’t, and to find out which materials worked best.

MW: What were the main challenges you anticipated when planning the construction?

MR: I don’t think I had any major concerns

initially. I was very much in a ‘make it up as I go along’ type of mindset. I might have been unsure how I was going to make the time rotator (clear cylinder in the middle) move up and down like in the show, but eventually I worked out a way.

MW: Did you have to make any design adaptations to fit the observatory setting, car, or any specific requirements?

on making it as big as it is, but because I had to design and build the whole thing in individual sections before assembling it all like giant puzzle, I couldn’t adjust on the fly.

MW: Were there any technical challenges you encountered during the construction?

MR: The good thing about cardboard is

it’s cheap, light, and easy to work with. The bad thing? It’s composed entirely of paper fibres. When I added the paper-mâché layers the glue soaked into it and warped everything out of shape, meaning nothing bolted together anymore. I (mostly) fixed this in the current version by using a thicker cardboard, a different glue/water ratio and more internal strengthening. That was just one of the many problems I ran into!

MW: Did you collaborate with other volunteers, people, or experts in specific areas during the construction?

MR: I certainly shared progress updates and

photos with my friends and other makers, but as far as collaborating with them? No, this was entirely a solo endeavour on my behalf which, in hindsight, was more than a bit crazy! It was a lot of fun though.

MW: What materials did you choose for the construction, and why?

MR: Because I don’t have access to a lot of money or high-tech tools besides a budget 3D printer, I opted to it out of cardboard because it was cheap and super easy to work with. There is a piece of MDF board at the base of the console to add strength, but aside from that, the rest of it is either various thicknesses of cardboard or craft foam.

MW: How long did it take to create?

MR: I had the idea about 2 years ago and started my first sketches and prototyping then. I began construction of this version in February of this year and got it to the stage it is now on the 23rd of November for the observatory’s Doctor Who night sky tour. A classic case of ‘It’s good enough to display!’

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MR: I’ve always had a fondness for

MR: Not particularly. I never planned

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MW: What inspired you to undertake the project of building a replica of the TARDIS control console?

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MW: Did you incorporate any functional elements, such as lights or sounds, to mimic the TARDIS experience? (It looked great with the lights on)

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MR: I knew from the get-go that I wanted the console to “function” like

the real prop with different lights, the ‘wheezing’ sounds of the Time Rotator, and the background ‘hum’. I’d wired up a soundboard to make these features come to life, but like any good project I ran out of time before having to bring it up here. I’ll be sure to add them in the future!

MW: How does the TARDIS control console replica fit in the car on the way up to the observatory?

MR: I wish I could tell you that my car is bigger on the inside, but it

isn’t. I knew getting the console the 250km drive from Bunbury to Perth was going to be a challenge, so I designed the console to come apart into around 20 separate parts of varying sizes. With that helpful design feature, coupled with years of playing puzzle-games, I was able to just squeeze everything into my car.

MW: Have there been any lessons learned in terms of upkeep and potential improvements?

MR: Yes. If (and when) I opt to build another Doctor’s console, or even

an updated version of this one, I’ll be sure to use the takeaways from this build to improve it. I would probably incorporate more mechanical connections and rely less on glues.

MW: Do you plan to rent it out to other events?

MR: I’ve had people bring this up before. Honestly, if there are venues

or event organizers that would like to hire it out, I’d be happy to let them!

MW: Do you have any plans for expanding or enhancing the TARDIS control console replica in the future?

MR: Definitely! Since bringing it down I have been working on numerous

greebles and other bits & bobs that I didn’t have time to add. The 9th & 10th Doctor’s console is supposed to be covered in cables, switches, knobs, dials, and other bizarre alien technology so there’s plenty more I’m going to add.

MW: Are there other science fiction or astronomy-related projects on the horizon for you?

MR: Always. Right now, I’m taking a step back from the larger, long-

term projects after working night & day for almost a year on this one.

But I am considering a life-sized, functioning R2-D2. I’d also love to construct a large-scale model of the International Space Station or other probes to hang from the observatory foyer. That would be cool, I think. At this stage, who knows?

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Image Credit: Matt Repacholi

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What’s In January’s Skies

By Matt Woods

2023 SUMMER EDITION

Planets: In January’s early morning sky, Mercury embarks on its celestial journey, transitioning from the constellation of Ophiuchus (The Serpent-Bearer) to Sagittarius (The Archer). On the 12th of the month, it reaches its greatest elongation in the West, marking the moment before retracing its path towards the Sun. Venus commences the month positioned between the constellations of Libra (The Scales) and Scorpius (The Scorpion). Throughout January, its radiant presence graces the night sky as it gracefully traverses Scorpius, and Ophiuchus, and ultimately culminates in the constellation of Sagittarius.

Mars, commencing its celestial voyage between Ophiuchus and Sagittarius, steadily progresses through the month, concluding its cosmic dance in the expansive realm of Sagittarius.

In the evening night sky, Jupiter‘s celestial residence in January is nestled between the mythological figures of Cetus (The Sea-Monster), and Aries (The Ram). Meanwhile, Saturn makes its ethereal abode in the constellation of Aquarius (The Water Bearer).

Uranus, the distant ice giant, graces the celestial tapestry between Taurus (The Bull), and Aries, adding a touch of cosmic allure to the vast expanse.

Neptune, the enigmatic ice giant, holds its celestial presence between the mythical constellations of Cetus and Pisces (The Fish), contributing to the captivating dance of the planets in the night sky throughout the month.

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Astronomical Events: Earth At Perihelion:

Things To Look At This Month: Winter Albireo: Winter Albireo (H 3945 and SAO 173349) is a visual double star in the constellation Canis Major and is named by Sir John Herschel (son of Sir William) and sometimes referred to as “Herschel’s Lovely Double” or the “Southern Albireo”.

This is not a binary system, but two stars in the same line of sight. The primary star is a Supergiant, ‘citrus orange’ in colour is much further away at 6523 lightyears away compared to its companion star which is a ‘royal blue’ coloured star at 258 light-years away.

Both stars are double stars themselves although not visible in our modest telescopes.

The orange star is a Supergiant over twice the diameter of Betelgeuse with a diameter of 2.6 billion km. It would encompass the orbit of Jupiter if in place of our Sun. It is also 365,000 times brighter than the sun because of its size, however, it has a much cooler surface temperature of 3 300 K. The secondary star is a much smaller main-sequence star at 2.9 times the diameter of the sun and 22 times the brightness with a much higher surface temperature of 7,300K.

2023 SUMMER EDITION

The Earth will be at its closest point to the Sun (at Perihelion), about two weeks after the December Solstice at 08:38 am (AWST) on Wednesday the 3rd of January. The Earth will be 147,100,632 km away from the Sun that day and this occurs because the Earth’s orbit is elliptical. Approximately every 100,000 years, Earth’s orbital path changes from being nearly circular to elliptical. This is due to the gravitational influences of other planetary objects, particularly the Moon. The difference in the Earth’s orbital path from a perfect circle is known as its eccentricity. Also, the word Perihelion comes from ancient Greek, where Peri means close, and Helios means the Sun.

2023 SUMMER EDITION

Image Credit: cs. astronomy.com

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SAO 173349

Winter Albireo

By Matt Woods

In the celestial tapestry of February’s early morning sky. Mercury, Venus, and Mars gracefully traverse the vast constellation of Sagittarius (The Archer) before dawn. On the 7th of February, all for three planets and the Moon will be in an alignment. As the month progresses, their celestial journey leads them into the constellation Capricornus (The Sea-Goat).

Venus and Mars, will grace the night sky throughout February and even be viewable in the same telescope eyepiece on the 23rd of February.

However, Mercury, the elusive messenger, will retreat into the Sun’s radiant glow, bidding farewell to the stargazers two-thirds into the month.

In the evening night sky, Jupiter commands attention as it asserts its presence between the cosmic realms of Cetus (The Sea-Monster), and Aries (The Ram), throughout the entire month. Meanwhile, Saturn, the majestic ringed giant, graces the constellations of Aquarius (The Water Bearer), until it succumbs to the Sun’s brilliance halfway through February.

Uranus, the first of the ice giants, positions itself gracefully between the constellations of Aries, and Taurus (The Bull). Neptune, the azure wanderer, navigates the starry seas between the constellations of Pisces (The Fish), and Cetus. As the month draws to a close, Neptune, too, vanishes into the Sun’s radiant farewell.

2023 SUMMER EDITION

Planets:

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What’s In February’s Skies

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Things To Look At This Month: Messier 46:

2023 SUMMER EDITION

Messier 46 is an unusual open star cluster in that it appears to have a planetary nebula (NGC2438) embedded in it. The cluster is about 40 light-years across and located some 5,500 light-years away from Earth. There are an estimated 500 stars in the cluster, and most are around 300 million years old — very young for stars.

While the planetary nebula appears to lie within M46, it is most likely unrelated to the cluster as it doesn’t share the cluster’s radial velocity. The star of this planetary nebula is a white dwarf with a surface temperature of about 74,700°C which makes it one of the hottest stars known to us.

2023 SUMMER EDITION

Image Credit: Jose Luis Martinez

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Messier 46

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What’s In March’s Skies

By Matt Woods

2022 SUMMER EDITION

Planets: Mercury is not viewable through March as it never leaves the Sun’s glare, but on the 25th of March, it reaches its greatest elongation in the East, marking the moment before retracing its path towards the Sun. In the early mornings of March, Venus graces the celestial canvas, initiating its celestial journey in the constellation of Capricornus (The Sea-Goat). Its luminous path takes it through the constellation of Aquarius (The Water Bearer), and positions it between the constellations of Cetus (The Sea Monster), and Pisces (The Fish). Notably, on the 22nd of March, Venus shares the cosmic stage with Saturn, creating a mesmerizing spectacle visible through a single telescope eyepiece.

Mars, a celestial companion to Venus at the start of March, commences its journey in the constellation of Capricornus, later finding its place in the constellation of Aquarius (The Water Bearer) by the month’s end. Meanwhile, Saturn, concealed by the Sun’s brilliance, reemerges in the evening sky towards the end of March, revealing its presence in the constellation of Aquarius.

As the sun sets, the evening sky unveils Jupiter‘s majestic presence, residing in the celestial expanse between the mythical figures of Cetus (The Sea Monster), and Aries (The Ram). At the beginning of March, Jupiter stands alone before embarking on a captivating cosmic convergence with Uranus, the first of the ice giants, situated between the constellations of Aries and Taurus (The Bull).

Autumn Equinox:

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On Wednesday the 20th of March, The Northward Equinox occurs at 11:07 am (AWST), marking the beginning of astronomical Spring for the Northern Hemisphere, and the start of Autumn for the Southern Hemisphere. This is an exact moment when the Sun’s declination equals 0 as seen from the Earth.

The two points where the ecliptic or the imaginary path the Sun seem to trace out along the celestial sphere meets the celestial equator are known as the equinoctial points.

2023 SUMMER EDITION

Astronomical Events:

The Equinox (literally meaning ‘equal nights’ in Latin) means that night and day are nearly equal worldwide, and that the Sun rises due east of an observer on the equinox and sets due west. The term Equilux is sometimes used to discern the difference between the true Equinox and the point when sunlight length equals the length of the night. Several factors play a role in this, including the time it takes the physical diameter of the Sun to clear the horizon, atmospheric refraction, and the observer’s true position in their respective time zone. The Equilux occurs within a few days of either Equinox.

Penumbral Lunar Eclipse: On March 25th, 2024 at 4:53 am (UTC), a penumbral lunar eclipse will occur. This type of lunar eclipse occurs when the Moon passes through the Earth’s outer shadow, known as the “penumbra” (From the Latin paene ‘almost, nearly’). During this event, the Moon will appear slightly darker than usual, as it will only be partially covered by the penumbra.

This penumbral lunar eclipse unfortunately, will not be visible from Western Australia, but it will be visible for much of Europe, North/East Asia, Much of Australia, Much of Africa, North America, South America, Pacific, Atlantic, Arctic, Antarctica. A penumbral lunar eclipse is not as spectacular as a partial or a total lunar eclipse, but it still offers a unique opportunity to witness a rare astronomical event.

Skywatchers will be able to see the subtle changes in the Moon’s brightness and colour as it passes through the penumbra. However, these changes will be quite subtle and may be difficult to discern without careful observation.

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Things To Look At This Month: Christmas Tree Cluster:

2022 SUMMER EDITION

The Christmas Tree Cluster (NGC 2264) is a young open cluster located in the constellation Monoceros (The Unicorn). It’s part of the NGC 2264 region, along with the Cone Nebula and the Fox Fur Nebula.

The cluster is located 2,700 light-years away from Earth and about 30 light-years across. The stars in the cluster were formed very recently from the surrounding molecular cloud. The cluster contains more than 600 stars that are 1 to 4 million years old.

The Christmas Tree Cluster is visible to the naked eye in good conditions and appears quite striking in binoculars. The Christmas tree shape can be seen in small telescopes at low power. The cluster can be found using the brightest stars of Orion and following a line drawn from Bellatrix to Betelgeuse to the east and a little bit north. The Christmas Tree Cluster is named for its triangular shape, formed by very young stars, that looks like a tree in visible light. It is in the northern part of NGC 2264, just above the Cone Nebula. The Christmas Tree Cluster was discovered by William Herschel on the 18th January 1784.

Christmas Tree Cluster 2023 SUMMER EDITION

Image Credit: Marcel Drechsler (Baerenstein Observatory)

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NGC 2264

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2022 SUMMER EDITION

Help Perth Observatory through the Containers for Change scheme.

Please take glass, plastic, aluminium, steel, and paper-based cartons between 150ml and 3L to your local refund depot and use the Perth Observatory (Scheme ID: C10424615).

The Perth Observatory Volunteer Group will receive 10 cents for each container. Save the ID on your phone for every time you recycle your containers. Find your local refund depot and get more info on what containers are eligible for refunds here:

containersforchange.com.au/wa

Can’t get to a refund centre? We have a dedicated and labelled bin on-site for you to add your clean container donations when you next visit the observatory.

Our maintenance volunteers collect donated containers and take them to the refund centre.

Thank you for helping the POVG promote sustainable and environmentally conscious practices and diversifying ways for us to raise much-needed funds.

Your help supports the continuing upkeep and running of Western Australia’s oldest observatory!

2023 SUMMER EDITION

CONTAINERS FOR CHANGE

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SUPPORT PERTH OBSERVATORY

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A Quick Festive Look In The Astroshop!

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2023 SUMMER EDITION

2023 SUMMER EDITION

Image Credit: Ronny Kaplanian

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NGC 1300

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2023 SUMMER EDITION

The Funny Side

Contact Us Perth Observatory 337 Walnut Road 6076 Bickley, WA (08) 9293 8255 newsletter@povg.org.au perthobservatory.com.au