November bulletin

VOLUME 2, Nº 3

DATE: NOVEMBER 2016

Reach the Sky Bulletin GLOBE AT NIGHT AT GORLICE Most of you have heard about light pollution, I’m sure. Nowadays, with more than half of the world’s population living in cities, 3 out of every 4 people in cities have never experienced the sight of truly dark skies. Where has the Milky Way gone? Where are the thousands of stars which were part of everyday life, inspiring artists like Van Gogh or writers like Shakespeare? Can we afford to lose touch with with our cultural heritage and with what could inspire future generations? And yet we’re doing so, allowing light pollution to wash out our starry night skies…

On 23rd November 2016, 34 students from I Liceum Ogólnokształcące im. Marcina

And what happens to your Globe at Night measurements? Scientists and citizen-scientists are using them in a variety of projects, most of which need multiple data points at the same location over time. In 2015, citizen scientists from around the world have contributed 13,878 data points.

Citizen scientists in 104 countries participated in Globe at Night in 2015. They submitted their data in 23 different languages!

Join us! Visit www.globeatnight.org to find out more.

Kromera in Gorlice took part in GLOBE AT NIGHT. You might wonder what it is, so let me explain. GLOBE AT NIGHT is an international campaign to raise public awareness of the impact of light pollution. Citizens all around the world are invited to measure their night sky brightness and then submit the results of their observations. All you need is a computer, tablet or smart phone.

Marzena Wójtowicz Poland

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What is the brightest thing in the universe ?

First let us see what the apparent brightness is, commonly used when stargazing refers to how bright an object appears to us when looking up from Earth. It depends on Earth-centric factors, like how close the object is to our planet. The magnitudes are logarithmic, lets see an example:

As we can see, a smaller number means a greater brightness. In other and we have the absolute brightness, a measure of how bright things all over the universe near and far would be if we looked at them from the same distance: 32,6 light-years away.

Absolute brightness will guide us to the most blinding light in the universe, irrespective of it looking faint to us here on Earth, just because it´s far away.

The difference is significant.

A 100 watt light bulb place closer than 8 cm from your eye will appear brighter than the Sun in the sky.

But if you could see the Sun and the bulb from the same distance, the Sun would be 4.000.000.000.000.000.000.000.000 times brighter… that´s brighter.

The Sun shines punily compared to the rest of the cosmos. If you could line the Sun up with everything else out there, to compare the shining of every star and cosmological phenomenon, the Sun´s absolute brightness would be 4.8…not bad…but check out R136a1, this nuclear fueled beast isn´t the biggest star in terms of volume but it´s 256 times more massive than our Sun. It´s the most massive star ever found and it´s also the brightest.

Remember that lower absolute magnitudes are

brighter R136a1 isn´t 4.8, like our Sun, it is -12.6, which means it is 8.7 million times brighter than our own Sun. But R136a1 isn´t the brightest thing out there.

When a giant star dies, it explodes violently in what is known as a supernova or hypernova.

Supernovas can eject terrifying flashes of radiation known as gamma ray bursts.

Arguably, the brightest electromagnetic events in the universe. A typical gamma-ray burst releases as much energy in a few seconds as our Sun will release altogether in its entire 10 billion year lifetime.

If WR104, a gamma-ray burst future candidate, directly struck Earth with such a beam for only 10 seconds, astronomers predict it could deplete 25% of our ozone layer and lead to mass extinction and starvation.

The largest thermonuclear bomb ever detonated didn´t do anything close to that and it was exploded right here, in our atmosphere.

Whereas WR104 is eight thousands light years away, you can´t even see it with your naked eye or a pair of binoculars. But gamma ray bursts are merely brief events lasting only a few minutes at most, sometimes just a matter of milliseconds. If you want the brightest sustained thing, you´ll paradoxically have to look at the darkest thing: Black holes.

To be fair, dark matter is ostensibly darker. But because dark matter has been hypothesized to not even interact with light, with electromagnetism at all, calling dark matter “not bright” is kind of like calling your peanut butter sandwich “a not fast airplane”. It´s not really even in the same category. Black holes, however, do interact with light, reflecting so little, well, they don´t let any scape, at least not in a form resembling the way in came in... That is dark.

But the intense energies created by black holes in the process of eating things like stars is anything

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but dark. Gas and debris from the stars they eat swirl into arcipluvian cosmic gallows known as accretion discs before making their final death plunge into the black hole. In the disc, debris spins at unfathomable speeds, pulled around by a black hole billions of times more massive than our Sun. Friction in the accretion disk generates heat on a level difficult to fully appreciate. Just as hot things glow, the disk does too, so brightly it has its own name: a quasar.

Quasars shine thousands of times more brightly than even the brightest stars and, more than that, quasars shine thousands of times more brightly than galaxies containing billions of stars.

The first identified quasar, 3C273 has an absolute brightness of -26.7, making it 4 trillion times brighter than our Sun, about 100 times more luminous than the total amount of light produced by the entire Milky Way. If you put 3C273 33 light years away from us it would shine as brightly as our Sun, a mere 8 light minutes away.

Blocking the brightness of a quasar with the corona graph reveals that quasars exist in the centers of galaxies that are larger than them in area, but are, nonetheless, drowned out by their light.

Such galactic centers are called active galactic nuclei.

The bulk of their energy spewing forth in the form of a powerful radiation jet, the length of which puts even our solar system to shame. The visible part of the jet, on the right side photograph, for instance, is so long it could stretch from the Sun to Pluto and back, one and a

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half million times.

Now, specifically, if a large portion of this ejected energy heads toward Earth it is responsible for we call quasar left picture 1 and 2).

But if Earth is right and the active galactic nucleus can be seen (3) it is name a blazar.

And it is blazar 3C453.3 that clocked in the greatest brightness ever observed. At historically high levels of activity it registered in absolute magnitude of -31.4 To put the brightness of quasars in yet another perspective, take a look at the hundred thousandth picture snapped by the Hubble telescope (picture below) the right side star is a few hundred light years away and the left one that looks just about as bright is not a star, it is a quasar 9 billion light years away.

Why are quasars so far away?

Well, a quasar is not forever. They are billions of light years away, which means the light we receive from them, the pictures we take of them, are pictures of things happening billions of years ago. They represent a phenomenon more common early in the universe´s history, when monster black holes hadn´t eaten all the stars around them to fuel their accretion discs and before those holes became too fat to be active. Some cosmologists point out that in order to remain a quasar producer, a black hole must consume about 10 stars a year, many consume more than a thousand stars a year, 600 Earths worth of matter every single minute. The more stars a black hole consumes, the larger its event horizon becomes, until, eventually, it no longer shreds stars apart to fuel an accretion disc. Instead, it just swallows them whole in one dimmer, but still terrifying, gulp.

Quasars are some of the most ancient things in our universe. If you could teleport instantaneously to one right now, faster than light, it would most likely no longer be burning.

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What we see are just their ghosts. Light that left when they were active that traveled longer than they could live.

But quasars can still be born. They can even be born right here, in fact. The Andromeda galaxy is headed our way. In 3 to 5 billion years it will collide with our own galaxy, the Milky Way, and the collision could rearrange stars near the galaxy´s central black holes to be consumed reigniting a quasar right here, in our galactic backyard.

Funny enough, right now very few of us even see Andromeda, even though all you need is your unaided eye. Light from our cities drowns out the night sky like a quasars drowns out its host galaxy.

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lice they were afraid of mysterious glowing clouds hovering above the city. They were seeing our galaxy for the first time in their lives.

At night, artificial lights allow us to see what is around us but we lose what is above us. The brightest places have the darkest, emptiest skies… The brightest things in the universe, quasars, are caused by the darkest things in the universe: black holes. The process that unshackles the most light is caused by the thing that best imprisons it. Is it not paradoxical?

Mª Jesús Domínguez Spain

In the 1990s, during a blackout in the city of Los Angeles a number of residence actually called the po-

PHOBOS: DOOMED MOON OF MARS This moon is doomed. Mars, the red planet named for the Roman god of war, has two tiny moons, Phobos and Deimos, whose names are derived from the Greek for Fear and Panic. These martian moons may well be captured asteroids originating in the main asteroid belt between Mars and Jupiter or perhaps from even more distant reaches of the Solar System. The larger moon, Phobos, is indeed seen to be a cratered, asteroid-like object in this stunning color image from the robotic Mars Reconnaissance Orbiter, recorded at a resolution of about seven meters per pixel.

Mars’ largest moon, Phobos, is slowly falling toward the planet.

But rather than smash into the surface, Phobos will likely be torn to shreds by the planet’s gravity and the pieces strewn about Mars in a ring, like the rings encircling Saturn, Jupiter, Uranus and Neptune.

Though inevitable, the demise of Phobos is not imminent, say scientists. It will probably happen in 20 to 40 million years, leaving a ring that will persist for anywhere from one million to 100 million years, according to two young earth scientists at the University of California, Berkeley.

Only Mars’ other moon, Deimos, would remain.

Webography: http://earthsky.org/space/mars-to-lose-its-largest-moongain-a-ring Andrea Gal Romania

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Galileo navigation Galileo is Europe’s own global navigation satellite system, providing a highly accurate, guaranteed global positioning service under civilian control. It is currently being created by the European Union through the European Space Agency and the European GNNS agency (global navigation satellite system). It is named after the Italian astronomer Galileo Galilei.The project costs 5 billion euros. It’s very similar as American GPS and Russian Glonass.

In June 2004, in a signed agreement with the United States, the European Union agreed to switch to a modulation known as BOC (Binary Offset Carrier) allowing the coexistence of both GPS and Galileo, and the future combined use of both systems. The European Union also agreed to address the mutual concerns related to the protection of allied and US national security capabilities.

communication network.

GNSS Simulator provide the user with ability to simulate different satellite constellations in a different way .It is accurate to the meter. The user can edit: - the location, - time, - signal level, - noise.

Knowing what is simulated and transmitted provides the ground for accurate receiver performance measurement.

Photo 2: Logo

Photo 1: Comprasion of GPS. Galileo and Glonass

The first Galileo test satellite, the GIOVE-A, was launched on 28 December 2005, while the first satellite to be part of the operational system was launched on 21 October 2011. As of December 2016, the system has 18 of 30 satellites in orbit. The fully deployed Galileo system will consist of 24 operational satellites plus six in-orbit spares, positioned in three circular Medium Earth Orbit (MEO) planes at 23 222 km altitude above the Earth, and at an inclination of the orbital planes of 56 degrees to the equator. Initial services will be make available by the end of 2016.

Then as the constellation is built-up beyond that, new services will be tested and made available, with system completion scheduled for 2020.

THE OPERATION ON THE SYSTEM: For the operation in Europe worry two control centers that receiving data from a global network of 20 sensors stations which are connected via a secure

SOURCES: https://sl.wikipedia.org/wiki/Slika:Galileo_logo.png http://galileo-nav.com/galileo-satellite-navigationproducts/galileo-satellite-navigation-in-doornavigation/ http://www.esa.int/Our_Activities/Navigation/Galileo/ What_is_Galileo https://www.gsa.europa.eu/european-gnss/galileo/ galileo-european-global-satellite-based-navigationsystem https://en.wikipedia.org/wiki/Galileo_ (satellite_navigation) https://sl.wikipedia.org/wiki/Galileo_ (satelitska_navigacija) http://siol.net/novice/novice/satelitski-sistem-galileo-je -operativen-2721 http://www.dijaski.net/gradivo/rif_ref_navigacija_01? r=1 Nejc Rudež Slovenia