September bulletin

VOLUME 2, Nº 1

DATE: SEPTEMBER 2016

Reach the Sky Bulletin THE SUNDIALS FORM PECICA The clock is an instrument for measuring time and was invented in antiquity. The simplest device that can measure the time during solar (or sundial). It consists of a stick fixed in a vertical plane which is oriented on the North-South direction and a horizontally plane arranged so that when sunlight falling on the stick, its shadow will be on the horizontal plane. Unfortunately, the device only works during the day and only when the sky is clear. Solar clock accuracy is not very high, considering that the Earth has a movement of revolution around the sun in an elliptical orbit.

With this device we can find out with a good accuracy the position of the cardinal points: follow the position and the length of the shadow left by a vertical stick during the day. When the length of this shadow has a minimum value, the shadow direction coincides with North-South direction, being directed to the North in Northern hemisphere and to the South in the Southern hemisphere. At that moment the Sun is on the location's meridian and used to say that it's "midday".

in 1223. With this solar clock we could read the correct time because this device measures the Solar time. The sundial has not 24 hour because it indicate the time during the day, while the Sun is up.

In Pecica, Romania, we found two sundials: one is located on the wall of the Bezdin Monastery (which was built in 1539) and the other one is realized into the building of the New Digital Museum of Pecica (2013).

How can you make a sundial?

Anyone can build a sundial in his own backyard. Stick a stick in the ground so that, at 12.00 his shadow to line with the Earth's axis of rotation In this way we could find the North in the northern hemisphere and the South in the Southern Hemisphere. The angle with the horizontal plane should be equal to the geographical latitude of the place. In Romania, this is 45.47 degrees. Around the stick plot a circle and note the number for hours indicated by shadows. The Solar day starts when the Sun passes the local meridian (at noon- midIn Romania, the oldest solar clock is located on the wall of day).

Itt Diana, Romania the Church of St. Bartholomew from Brașov, which was erected

Astronomical myths and legends Astronomy is one of the oldest scientific discipline, which But not only constellations, in fact all lot of planets in is getting more and more popular. The first step to deeper our solar system are named after Roman and Greek gods: explorations and stellar secrets is usually a stellar story or Mercury - Roman god of commerce, trade and freight myth. transport.

Venus - Roman goddess of love.

Earth - Greek goddess of earth and land.

Mars - Roman god of war, spring and justice.

Jupiter - King of the Roman Gods – god of the sky, thunderstorms, lightning, weather and air.

Saturn - Roman god of agriculture, fruit farming, sowing and viticulture.

Uranus - Greek god of sky and universe.

Neptune - Roman patron of Ancient people make up a lot of stories and myths that sailors and the protector of we still know today. When they were staring at the night sky ships. they do not see only thousands of stars, but they see full figures. When they connect the dots, they make shapes and Sara Vehovar, Slovenia sometimes these shapes remind them of their gods, animals, objects.

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DECLARATION IN DEFENCE OF THE NIGHT SKY AND THE RIGHT TO STARLIGHT (LA PALMA DECLARATION)

The protection and preservation of the night sky is an important scientific, cultural, environmental and tourist resource.

It is important to instill among the public awareness of the importance of smart lighting habits and to promote local, national and international initiatives to prevent light pollution, which enable energy savings and the mitigation of the effects of climate change.

Bearing in mind that the Universal Declaration of Human Rights of Future Generations states that persons belonging to future generations have the right to an uncontaminated and undamaged Earth, with pure skies, and are entitled to enjoying these as the ground of human history of culture and social bonds making each generation and individual a member of one human family among others, the participants in the International Conference in Defence of the Quality of the Night Sky and the Right to Observe the Stars, meeting in La Palma, Canary Islands, Spain, on the 19th and 20th of April 2007, jointly with the representatives of UNESCO, UNWTO, IAU, UNEP-CMS, COE, SCBD, MaB, EC and Ramsar Convention, adopted the following principles and objectives: 1 An unpolluted night sky that allows the enjoyment of the contemplation of the firmament should be considered an inalienable right of humankind equivalent to all other environmental, social, and cultural rights, due to its impact on the development of all peoples and on the conservation of biodiversity.

2 The progressive degradation of the night sky must be considered an imminent risk that must be faced, in the same fashion as the main problems concerning resources and the environment are addressed.

3 The conservation, protection, and revaluation of the natural and cultural heritage associated with night landscapes and the observation of the firmament represents a prime opportunity and obligation for cooperation in safeguarding the quality of life. For all decisionmakers, this attitude implies a genuine challenge involving cultural, technological, and scientific innovation, requiring a major constant effort to enable us to rediscover the presence of the night sky as a living part of our heritage.

4 Access to knowledge, armed with education, is the key to allow the integration of science into our present culture,

contributing to the advance of humankind. The dissemination of astronomy and the scientific and cultural values associated with the contemplation of the universe should be considered as basic contents to be included in educational activities, which require a clear and unpolluted sky and proper training of educators in these subjects.

5 The negative effects of emissions and of the increased intrusion of artificial light on the atmospheric quality of night skies in protected areas have an impact on several species, habitats, and ecosystems. Control of obtrusive light must be a basic element of nature conservation policies and should be implemented in the management plans of the different types of protected areas to fulfil their mission in protecting nature and biological diversity.

6 Mindful that a starry night sky forms an integral part of the landscape perceived by the inhabitants of every territory, including urban areas, the landscape policies established in the different juridical systems need to adopt the pertinent standards for preserving the quality of the night sky, thus allowing them to guarantee the common right to contemplate the firmament.

7 The intelligent use of artificial lighting that minimises sky glow and avoids obtrusive visual impact on both humans and wildlife has to be promoted. Public administrations, those in the lighting industry, and decisionmakers should also ensure that all users of artificial light do so responsibly as part of an integral part of planning and energy sustainability policies, which should be supported by light pollution measuring, both from the ground and from space. This attitude would involve a more efficient use of energy so as to meet the wider commitments made on climate change, and for the protection of the environment.

8 Areas suitable for unimpaired astronomic observation constitute an asset in short supply on our planet, and their conservation represents a minimum effort in comparison with the benefits they contribute to our know-how and to scientific and technological development. The protection of sky quality in these singular places must be given priority in regional, national, and international scientific and environmental policies. The measures and provisions must be made to safeguard clear skies and to protect such spaces from the harmful effects of light, radioelectric emissions, and air pollution.

9 Among others, tourism can become a major instrument for a new alliance in defence of the quality of the night sky. Responsible tourism can and should take on board the night sky as a resource to protect and value in every destination. Generating new tourist products based on the observation of the firmament and the phenomena of the night, opens up unsuspected possibilities for co-operation between tourism stakeholders, local communities, and scientific institutions.

10 Sites included in the World Network of Biosphere Reserves, Ramsar Wetlands, World Heritage Sites, National Parks, and all those protected areas which combine exceptional landscape and natural values relying on the quality of their night sky, are called for including the protection of clear night skies as a key factor strengthening their mission in protecting nature.

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THE GREATEST POLISH ASTRONOMERS Jan Heweliusz Jan Heweliusz was born in Gdańsk. His father was Abraham Hewelke and his mother Kordula Hecker. He studied the Polish language in Gądecz. After gymnasium, in 1630, he studied jurisprudence at Leiden, then travelled to England and France. In 1634 he settled in his native town, and on 21 March 1635 married Katharine Rebeschke, a two years younger neighbour. The following year, Hevelius became a member of the beer-brewing guild.

Works written by Hevelius: -Selenographia (1647) -De nativa Saturni facie ejusque varis Phasibus (1656) -Historiola Mirae (1662) -Prodromus cometicus (1665) -Cometographia (1668) -Machina coelestis (first part, 1673) In 1641, he built an obser vator y on the roofs of his three connected h o u s e s , equipping it with splendid instruments, ultimately including a large Keplerian telescope of 46 m (150 ft) focal length, with a wood and wire tube he constructed himself. It was known with a name "Star Castle".

One of the Polish queens visited it personally. Hevelius was glad to have the patronage of four consecutive kings of Poland.

Aleksander Wolszczan Aleksander Wolszczan was born 29 April 1946 in Szczecinek. He is a Polish astronomer. He is the co-discoverer of the first extrasolar planets and pulsar planets.

Working with Dale Frail, Wolszczan carried out astronomical observations from the Arecibo Observatory in Puerto Rico, which led them to the discovery of the pulsar PSR B1257+12 in 1990. They showed in 1992 that the pulsar was orbited by two planets. The radii of their orbits are 0.36 and 0.47 AU respectively.

This was the f i r s t confirmed discovery of p l a n e t s outside the Solar System (over 1,750 are known today).

Wolszczan is a member of: -Polish Academy of Sciences, -American Astronomical Society, -American Association for the Advancement of Science, -International Union of Radio Science, -International Astronomical Union, -Polish Institute of Arts and Sciences of America.

Wolszczan used the Arecibo radio telescope in Puerto Rico to find three planets the first of any kind ever found outside our Solar System circling a pulsar called PSR B1257+12. Pulsars are rapidly rotating neutron stars, which are the collapsed cores of exploded massive stars. They spin and pulse with radiation, much like a lighthouse beacon.

Since this landmark discovery, more than 160 extrasolar planets have been observed around stars that are burning nuclear fuel. The planets spotted by Wolszczan are still the only ones around a dead star. They also might be part of a second generation of planets, the first having been destroyed when their star blew up. The Spitzer Space Telescope's discovery of a dusty disk around a pulsar might represent the beginnings of a similarly "reborn" planetary system.

Bohdan Paczyński Bohdan Paczyński was born on 8 February 1940 in Vilnius, Lithuania, to a lawyer and a teacher of Polish literature.

In 1945 his family chose to leave for Poland and settled in Kraków, and then in 1949 in Warsaw. At the age of 18, Paczyński published his first scientific article in Acta Astronomica. Between 1959 and 1962 he studied astronomy at the University of Warsaw. Two years later he received a doctorate.

In 1962 Paczyński became a member of the Centre of A s t r o nom y

of the Polish Academy of Sciences, where he continued to work for nearly 20 years. In 1974 he received habilitation and in 1979 became a professor. Thanks to his works on theoretical astronomy, at the age of 36 he became the youngest member of the Polish Academy of Sciences.

Paczyński was the initiator of Optical Gravitational Lensing Experiment (OGLE), led by Andrzej Udalski of Warsaw University Observatory and All Sky Automated Survey (ASAS), created together with Grzegorz Pojmański.

His new methods of discovering cosmic objects and measuring their mass by using gravitational lenses gained him international recognition, and he is acknowledged for coining the term microlensing. He was also an early proponent of the idea that gamma-ray bursts are at cosmological distances.

He was honoured with the title of doctor honoris causa by Wrocław

University in Poland (on June 29th, 2005) and Nicolaus Copernicus University in Toruń in Poland (on September 22nd, 2006).

In January 2006 he was awarded Henry Norris Russell Lectureship of the American Astronomical Society, "for his highly original contributions to a wide variety of fields including advanced stellar evolution, the nature of gamma ray bursts, accretion in binary systems, gravitational lensing, and cosmology”.

He died of brain cancer on April 19th, 2007 in Princeton, New Jersey Sources: www.wikipedia.org; www.princeton.edu; www.astro.psu.edu; www.encyclopedia.com; www.nature.com; www.trojmiasto.wyborcza.pl; www.phys-astro.sodoma.edu Weronika Pyzik , Martyna Kucharczyk , Sara Słyś , Poland

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THE SUN ROTATION That the Sun rotates is an observational result known since Galileo pointed to the sky for the first time with his telescope in 1608.

Contrary to those period ideas, that celestial objects, including the Sun, were perfect and unblemished objects, supported by Aristotle and accepted by the Catholic Church as dogmas of faith, Galileo's observations showed that on the Sun`s surface there were dark spots that appeared and disappeared with days or weeks periods. These spots were moving on the solar disk from east to west and took about two weeks to cross it. Galileo correctly explained these observations by the Sun's rotation on an axis slightly tilted toward Earth.

Today we know that the Sun rotates on its axis having a maximum inclination of about 7 degrees respect to Earth orbit plane, also we know that the sun, which is not a rigid solid, rotates differentially, ie, rotates faster at Equator than at the poles, so that, meanwhile in Equator takes about 26 days to complete one lap, near the poles takes more than 30 days. This Sun differential rotation plays a very important role in our star life, along with convection, is responsible for the solar magnetic field generation and maintenance according to current theories.

We know, therefore, that the Sun rotates on its surface, differentially rotating and this rotation governs an important part of the star life, but what happens inside the Sun? Does the inside of the sun rotates at same way as on the surface?

Does it remain in its interior any memory of its rotation from its formation period? The answers to these questions are the key to understand the solar magnetic field generation mechanisms and conservation, but do not have an easy answer because the Sun is opaque and we cannot look inside, at least directly.

However, there are indirect ways to see inside the Sun and this observation is so important for understanding the Sun internal structure and thus, the stars structure, of which the Sun is just one more of them.

On December 1995, an artificial satellite SOHO (Solar and Heliospheric Observatory) was launched, dedicated exclusively to our star study. This satellite, located in 1.5 million km from Earth, is an international cooperation project between the European Space Agency ESA and the US Space Agency NASA. The satellite has 11 instruments on board, 3 of them dedicated to the Sun's interior observation by "heliosismologic" techniques. Helioseismology is the technique that allows us to "see" inside the Sun and is based on the same techniques that have allowed us to know what the internal Earth structure is: the inside wave propagation study. These waves, generated in earthquakes, in seismic or artificially movements allowed us to extract information from the inside Earth, since the wave propagation direction

and speed depends on the temperature and chemical composition from the zones that the wave passes through. Now, how can we get this information from the Sun, since we cannot put seismometers on the surface?

Inside the Sun are generated and propagated different types of waves that produce movements in the solar gas atmosphere , and it`s this movement from the Sun surface layers ,produced by the waves that are propagated in its interior the ones that can be measured, for example, small changes in the radio, temperature or star power.

These are the Sun's interior indirect measures that have allowed us to know, among many other results, how the inside sun rotates.

In this way we could know that the inside sun rotates in the same way that on its surface, ie, rotates faster in Ecuador than at the poles, along its entire convective zone: a third of the solar radius and, from here, it rotates as a rigid solid. The narrow area in which this rotation change occurs is situated in the lower part of the solar convection zone called "Tachocline" and currently is where the solar magnetic field generation and maintenance area are located. This Sun internal rotation, with the appearance of the Tachocline, whose existence was not suspected before the SOHO observations, has led to progress and deepen our understanding in the sun`s magnetic field generation , which is not today entirely clarified yet.

But, It is important that the Sun rotates?, Does it affects us how the Sun rotates?, Is it worth so much effort, not only human but also economic, to try to understand what happens in the Sun? From the philosophical implications that had at the time that the heavens were not immutable until the real solar magnetic fields effects that today we know that affect our daily life, through the mere desire of knowledge, the answer to all these questions is YES. When Galileo discovered that the time it takes an object to fall a given distance from rest is proportional to the square root of that distance, science was born, the idea that a mathematical formula, not a god, controlled the material world`s behavior was born. Science helps us build an picture of the objective reality and help us to position ourselves in it. The Sun rotation is another piece of knowledge that, together with many others, allows us to understand the universe around us, which will certainly help us to understand what mankind is.

Dr. Clara Régulo Rodríguez. Solar Physics, IAC, Spain Translation: Jesús Otaiza