Star Party 2009 » Astronomy

Celestial Sphere

admin — Fri, 17 Apr 2009 15:41:00 +0000

Celestial Sphere

Lecturer – J D Prasanna Deshapriya
Event – Observation Camp of Asian International School on March 30, 2009

Have you ever wondered how far the starts really are away from us? Well, what are the closest and most distant stars? If you could provide a better solution for above questions, you are not that far from the correct answer.

If you observe the night skies, it seems that all the stars are same distance away from us. Therefore to make it easy to study, we assume that all the stars lie in a surface of a sphere, whose center is concentric with that of Earth. This sphere is known as “Celestial Sphere”

It is important to understand that each star occupies a unique location of its own, as same as a country does, in the surface of the Earth. The celestial sphere is divided in to 88 parts, each of which contains a constellation.

To identify a location of celestial sphere, we use co-ordination system as same as latitudes and longitudes are used to determine the geographical locations.

Let’s get known more about the geographical co-ordination system. The Earth is divided into two equal parts by the equator. The upper part is called Northern Hemisphere where as the portion, below the equator is called Southern Hemisphere. The lines that are drawn in parallel to the equator are called latitudes and the lines that are perpendicular to the equator are called longitudes. Using this co-ordination system we could explain any single point on the surface of the Earth, since each location has its own attributes of above-mentioned values (latitude & longitude).

Co-ordination Systems of Celestial Sphere

Now, let’s derive a method to explain a location of celestial sphere. In fact there are two systems in use. These systems help us determine the locations of the stars on the celestial surface.

1. Equatorial Co-ordination system (RA-Dec)

If you could project the attributes of previously discussed terrestrial co-ordination system to the celestial sphere you would get a formal system of co-ordinates for the celestial sphere as well. The celestial equivalent of the equator will be Celestial Equator, where as corresponding components of the latitudes and longitudes will be Declination and Right Ascension (RA-Dec), respectively. Therefore the location of a star will be given in RA and Dec in this system which is known as Equatorial Co-ordination system.

The measurement of declination will be dealt with angles. The values of the declination will be measured as positive (+) if the object/ star is in the northern celestial sphere and the angular values of the southern hemisphere will be assigned a minus (-) value. The measurement of Right Ascension is done by hours. In convention, celestial equator is divided into 24 hours, while an hour is divided into 60 minutes and a minute into 60 seconds.

For example the equatorial co-ordinates of the star Sirius will be RA} 06h 45m and Dec} -16 0 43’

2. Horizontal Co-ordination system (Alti-Azimuth)

Understanding of horizontal co-ordination system is very easy. Suppose you get an object in the sky and you need to find out the horizontal co-ordinates. Measurement is as thus. The value of clockwise angle from north to that object is called as Azimuth of the object. The value of the minimal angle from your horizon will be the altitude of the object.

However the more precise system is RA-Dec system.

You might now ask why we need two co-ordination systems. Suppose you told a friend the location of an object with horizontal system. But you need to provide him in detail, the observable time, date and location as well, since the position of the object varies with the time. You have to mention the time as the Earth moves 15 0 per an hour. Thus the location of an abject varies relatively to time. However this change does not affect the Equatorial system, since the system, itself is independent of time.

Equinoxes and Ecliptic

Generally the Sun is considered as a celestial object. But it doesn’t have a unique position in the celestial sphere. However we can draw a line which can illustrate the locations, where the sun will be on. This line or path is called Ecliptic. The Moon and other planets have their trajectories near the ecliptic. When planets are observed, observation should be done in close proximity to ecliptic.

There are two points, where ecliptic crosses the equator. There points are called as equinoxes. The Sun, during its motion arrives at equator from either southern or northern hemispheres. If sun arrived from southern hemisphere, the equinox is called Vernal (March) Equinox, whereas the Sun’s arrival from the northern hemisphere being called as Autumnal (September) Equinox and these arrivals occur on 21st of March and 21st of September respectively.

Technical Words used in Observational Astronomy

1. Zenith – If you draw an imaginary line directly above your head, the point that the line crosses the celestial sphere is called as Zenith.
2. Nadir – If you draw imaginary line directly below your legs, the point that the line crosses the celestial sphere is called as Nadir.
3. Celestial poles – The corresponding poles that you get when the axis of the Earth is extended and celestial sphere rotates around these poles
4. Meridian – The imaginary circle that you get when the north and south of the horizon and Zenith is joined vial a line. This is also called as Hour Circle

Copyrights Reserved: Anandian Astronomical Association (AAA)

IYA 2009 launch at The University of Guelph, Canada

admin — Sun, 01 Mar 2009 02:23:00 +0000

The official launch of IYA 2009 at the University of Guelph will be marked with a large range of activities, including public outreach workshops, star-gazing camps and etc. The featured release of a new “star-studded” digital EP during a University function will be conducted by composer /singer and professor of physics Dr. Diane Nalini de Kerckhove.

This year was chosen by the United Nations Educational, Scientific and Cultural Organization (UNESCO) to mark the 400th anniversary of Galileo’s first use of a telescope.

The series of lectures will commence on 4th of March and the initial lecture will be delivered on “A Random Walk Through Ancient Astronomy” by an emeritus physics professor Dr. Jim Hunt.This will be followed by another lecture on “The Discovery of Extra-solar Planets” on 1st of April and this is to be delivered by Dr.Debra Fischer, astronomy professor at San Francisco State University.

Both lectures will be at 7 p.m. in Room 101 of Rozanski Hall

“The discovery of the first extra-solar planets in the 1990s was a landmark event,” says de Kerckhove, co-organizer of this year’s events. “It captured the imagination and really opened the public’s mind to the possibility of life elsewhere in the universe.” she added.

The featured release will be conducted by her, under her stage name, Diane Nalini, on March 27 at 7:30 p.m. in Rozanski Hall. The concert will launch a digital EP of astronomy-themed songs, recorded early this year in Toronto. The event is sponsored by the Office of the President.

Other Guelph IYA events include observatory viewings at the MacNaughton Building telescope during Alumni Weekend later this year. Organizers are planning to promote the events to local high schools and throughout Guelph and popularize the IYA 2009 while it lasts.

Speaking further, De Kerckhove said that she would hope participants could learn not just about the night sky but also about how science works and about the personal side of early astronomers, including Galileo, Tycho Brahe and Johannes Kepler, who had rendered an enoromous service towards the upheaval of astronomy. Lastly she was quoted saying “Astronomy to me has a beautiful purity. It’s about understanding how we fit into the world.”

For more information, check out the website
www.physics.uoguelph.ca/outreach

Function tickets are available at the University Bookstore and Ground Floor Music

IYA 2009 launched in Edinburgh, Scotland

admin — Thu, 26 Feb 2009 05:27:00 +0000

Professors, scientists, accredited personnel, amateur astronomers, teachers and outdoor educators flocked at the Royal Observatory Edinburgh on 25th Feb. 2009 morning , to remark the launch of the International Year of Astronomy 2009 (IYA 2009) in Scotland.

It is planned to host a variety of activities throughout the country and hosting will be conducted by affiliated Universities, schools, astronomy societies, education institutions and environmental groups. Activities include star-gazing, public discussions, exhibitions to celebrate the legendary 400th year since Galileo Galilei’s first observations of the night sky with a telescope. Professor Ian Robson, Director of STFC’s UK ATC and the UK Chair for IYA 2009, who is based at the Royal Observatory said, “The year is a global celebration of astronomy as one of humankind’s greatest achievements.”

As a part of the launch of IYA in Scotland, teachers and pupils from Galashiels Academy in the Scottish Borders and Liberton High School in Edinburgh are to be awarded telescopes, in connection with the “Telescopes for Schools” project, by Professor John Brown, Astronomer Royal for Scotland. Moreover Suzanne Pritchard, a physics teacher at Galashiels Academy, says: “This is perfect timing for us”. ” With the freedom of the new Curriculum for Excellence, the telescope gives our pupils a fantastic opportunity to have a go at real observing, guided by a real astronomer” she added.

Thus ninety schools in Scotland will be granted telescopes as part of the project, which is led by the Society for Popular Astronomy to inspire the next generation of scientists and engineers, which is very essential as far as modern status of Astronomy is concerned. Speaking further, Professor John Brown says of the programme: “Scotland will have a tremendously vibrant and exciting programme of astronomical and dark sky events for the public and schools, led by researchers, amateur astronomers and science communicators.”

It’s great to see the voluntary community is leading the way right across Scotland to popularize and improve the understanding of both IYA 2009 and Astronomy. Bill Leslie, from SIGMA, the astronomy club for Moray, will be running activities throughout the Highlands and Islands. Bill says: “The year will really put the spotlight on the fantastic range of events run by Scotland’s amateur astronomy groups.”

Professor Anne Glover, Chief Scientific Advisor for Scotland says: “The Scottish Government is providing over £100,000 to help fund a range of public astronomy events across Scotland this year. This includes a grant of £49,000 for projects co-ordinated by the Royal Observatory Edinburgh. Stargazing is a great way to encourage our young people to engage with science and I’m delighted that many of the events planned for IYA2009 have families and young people at their heart.”

That’s the updates of Scottish IYA 2009 schedule.

Be updated with us!!… Link: http://www.edinburghguide.com/story/education/3020

Astronomical Society of Dharmaraja College, Kandy

admin — Fri, 20 Feb 2009 16:06:00 +0000

Briefing:

Dharmaraja College-Kandy has a long based history regarding astronomy. But it was around the year 1996, the ASTRONOMICAL SOCIETY of DHARMARAJA COLLEGE (ASDRC) KANDY-SRI LANKA, legally came into existence. It is the common meeting place for students of Dharmaraja College to communicate-investigate-standardizethe knowledge pertaining to astronomy and allied sciences. Since then, ASDRC was able to serve the school community as well as the entire nation with a wealth of scientific intuition. Today it remains the unprecedented high-school Astronomical Society in Sri Lanka besides being the progenitor institution for a number of other astronomical societies all around the country. Now with immense pride and prestige, it has entered the global community as well.

Updates:

Astronomical Society of Dharmaraja College held its annual Astronomy workshop on Saturday, 15th November 2008 in grand scale. Theme of the program was ‘Expanding The Universal Imagination ’08′. Senior Professor Tissa R. Herath conducted a great lecture on Astrobiology and another lecturer, Sumudu Weerasekera conducted a lecture on Solar System. There were enough items to keep up the attendees all night and examine their knowledge. ‘Astro Olympiad’ challenge trophy – the most prestigious inter-school Astronomy quiz competition in the Sri Lankan Astronomy quiz arena, conducted by ASDRC for the 7th consecutive year, was won by Nalanda College, Colombo-10 and observation title was taken by Ananda College, Colombo-10. Quiz competition was held as preliminary round, semi finals and grand final, as usual. The Rajans’ Sky Observation competition was organized for the third consecutive year. Due to the non favorable weather conditions on that day, observation competition was circumscribed to Moon Sketching, Deep Sky Observation and Constellation Mapping. Organizers received a very good internal and external response for their work. Committee extends its utmost heartfelt gratitude to all its members and past pupils who contributed to make this event a success.

Links:

http://www.dharmaraja.org

ASDRC on Facebook

Space Carnival: An innovative introduction.. 51st edition..

admin — Tue, 17 Feb 2009 08:03:00 +0000

“”"Hello and welcome to the 51st edition of the Carnival of Space! My name is Ian O’Neill, UK solar physicist and writer for the Universe Today. I am honoured to be hosting the Carnival, so thank you Fraser for letting me loose on seven days-worth of excellent space related news from the growing blogosphere. Astroengine is my online home, delving into the inner workings of the cosmos, so it’s good to freshen the site up with news from a superb cross-section of space blogs.

There is a huge breadth of topics this week with no particular trend, but as Earth Day was on April 22nd, I’ll kick off with the some of the stories a little closer to home (and then end up somewhere in the proximity of the Big Bang, 13.7 billion years ago). As said by the great Yuri Gagarin, “I see Earth! It is so beautiful!” I begin with our Blue Planet…”"”

Cosmic Origins Revealed….

admin — Mon, 16 Feb 2009 04:33:00 +0000

By National Radio Astronomy Observatory, [RxPG] Processes that laid the foundation for life on Earth — star and planet formation and the production of complex organic molecules in interstellar space — are yielding their secrets to astronomers armed with powerful new research tools, and even better tools soon will be available. Astronomers described three important developments at a symposium on the Cosmic Cradle of Life at the annual meeting of the American Association for the Advancement of Science in Chicago, IL.

In one development, a team of astrochemists released a major new resource for seeking complex interstellar molecules that are the precursors to life. The chemical data released by Anthony Remijan of the National Radio Astronomy Observatory (NRAO) and his university colleagues is part of the Prebiotic Interstellar Molecule Survey, or PRIMOS, a project studying a star-forming region near the center of our Milky Way Galaxy.

PRIMOS is an effort of the National Science Foundation’s Center for Chemistry of the Universe, started at the University of Virginia (UVa) in October 2008, and led by UVa Professor Brooks H. Pate. The data, produced by the NSF’s Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, came from more than 45 individual observations totalling more than nine GigaBytes of data and over 1.4 million individual frequency channels.

Scientists can search the GBT data for specific radio frequencies, called spectral lines — telltale fingerprints — naturally emitted by molecules in interstellar space. We’ve identified more than 720 spectral lines in this collection, and about 240 of those are from unknown molecules, Remijan said. He added, We’re making available to all scientists the best collection of data below 50 GHz ever produced for the study of interstellar chemistry, Remijan said.

Astronomers have already identified more than 150 molecules in interstellar space in the past 40 years, including complex organic compounds such as sugars and alcohols. This is a major change in how we search for molecules in space, Remijan explained. Before, people decided beforehand which molecules they were looking for, then searched in a very narrow band of radio frequencies emitted by those molecules. In this GBT survey, we’ve observed a wide range of frequencies, collected the data and immediately made it publicly available. Scientists anywhere can ‘mine’ this resource to find new molecules, he said.

Another key development, presented by Crystal Brogan of the NRAO, showed that highly-detailed images of protoclusters of massive young stars reveal a complex mix of stars in different stages of formation, complicated gas motions, and numerous chemical clues to the physical conditions in such stellar nurseries. We saw a much more complex picture than we had expected and now have new questions to answer, she said.

Using the Smithsonian Astrophysical Observatory’s Submillimeter (SMA) in Hawaii, Brogan and her colleagues studied a nebula 5,500 light-years from Earth in the constellation Scorpius where stars significantly more massive than our Sun are forming. It’s essential to understand what’s going on in systems like this because most stars, Sun-like stars included, form in clusters, Brogan said.

The most massive stars in the cluster have a tremendous impact on the formation and environment of the rest of the cluster, including the less-massive stars and their planets, Brogan said, adding that if we want to understand how solar systems that could support life form and evolve, we need to know how these giant stars affect their environment.

Also, Brogan said, the massive young stars are surrounded by hot cores that include copious organic material that later may be spewed into interstellar space by stellar winds and other processes. This can help seed star-forming regions with some of the chemicals found by the GBT and other telescopes.

Narrowing in on the problem of how planets form around young stars, David Wilner of the Harvard-Smithsonian Center for Astrophysics presented observations with the SMA that revealed new details of solar systems in the earliest stages of their formation. Wilner and his colleagues studied nine dusty disks surrounding young stars in a region in the constellation Ophiuchus.

These are the most detailed images of such disks made at these wavelengths, Wilner said. The images show the distribution of material on the same size scale as our own Solar System, and indicate that these disks are capable of producing planetary systems. Two of the disks show large central cavities where young planets may already have swept out the material from their neighborhoods.

Before, we knew that such disks have enough material to form solar systems. These new images tell us that material is in the right places to form solar systems. We’re getting a tantalizing peek at the very earliest stages of planet formation, said Sean Andrews, a Hubble Fellow at the CfA.

All three areas of study are poised for major advances with the impending arrival of powerful new radio-telescope facilities such as the Atacama Large Millimeter/submillimeter (ALMA) and the Expanded Very Large (EVLA), and new capabilities for the GBT.

Studies of protoplanetary disks and young solar systems will benefit greatly from the groundbreaking new capabilities of ALMA, Wilner said. While we’ve been able to study a few of these objects so far, ALMA will be able to give us highly-detailed images of many more that we can’t study today, he said. Wilner added that ALMA also will likely provide new information on the chemicals in those still-forming planetary systems.

The complex motions and chemistry of Brogan’s protoclusters of young, massive stars, also will become much clearer with ALMA. Both the detail of the images and the ability to find molecular spectral lines will improve by a factor of at least 25 with ALMA, she said. In addition, the increased power of the EVLA will give astronomers a far better look into the inner regions of the disks around young stars — regions obscured to telescopes operating at shorter wavelengths.

We know that complex chemicals exist in interstellar space before stars and planets form. With the new research tools coming in the next few years, we’re on the verge of learning how the chemistry of the interstellar clouds, the young stars and their environments, and the disks from which planets are formed is all linked together to provide the chemical basis for life on those planets, Remijan explained.

Astrophysicist Neil deGrasse Tyson of the American Museum of Natural History noted, Like no other science, astrophysics cross-pollinates the expertise of chemists, biologists, geologists and physicists, all to discover the past, present, and future of the cosmos — and our humble place within it.

Approaching Comet Lulin

admin — Sat, 14 Feb 2009 07:23:00 +0000


Comet Lulin is with a tail and an anti-tail on January 19, 2009, when Michael Jaeger photographed this image from Austria, using an 8-inch f/2.8 astrographic camera for exposures through LRGB filters totaling 10 minutes.	Comet Lulin on February 2nd 2009, at magnitude 6.5 with tail and anti-tail. See the difference between two images.

Various tail images from the Comet Lulin.

Comet Lulin was discovered in 2007 by a Strait-bridging team of astronomers from Taiwan and China. Lulin is swinging around the sun and approaching Earth. Astronomer Karzaman Ahmad had this picture taken 7th Jan. 2009 from the Langkawi National Observatory in Malaysia

Resources:

http://www.skyandtelescope.com/observing/highlights/35992534.html

http://www.christian-forum.net/index.php?showtopic=27562

http://apod.nasa.gov/apod/ap090202.html

IYA 2009 LK affiliated Observation Camp at Piliyandala

admin — Sat, 14 Feb 2009 06:24:00 +0000

Yesterday, 13th of Feb. 2009 I got a chance of contributing to the 4th annual Observation Camp organized by the Leo Club, Piliyandala for the students of Kahapola Junior College. I was glad to see nearly 100 students from Grade 7 to 11 flocking together for such a scientific gathering. Camp took place at the college premises, starting at 6.30 pm and lasted till the the dawn of the next day.

The participants got a fair knowledge on Observational Astronomy and had a team work session, where they made impressive modes of the Colombia Space Shuttle in memory of the 6th anniversary of the honourable astronauts of the very Shuttle.

Apart from the indoor activity, they had the outdoor observation session and everybody got a clear impression on star charts and got familiar with celestial bodies, thus adding a variety for their normal routine. The Lunar phrases, and rings of the Saturn were clearly observed with a Newtonian Telescope with an Alti-Azimuth mounting system.

At the end everybody, including teachers and parents were capable of having a promising impression on Observational Astronomy. Accredited personnel from AALK ( Astronomical Association of Sri Lanka ), Skylk and ASSC ( Astronomy & Space Study Center ) contributed their voluntary service to this endeavour. Also a special thank goes out to the members and BoO of Piliyandala Leo Club for making the necessary arrangements under their Educational Projects.

This Observation Camp was held in affiliation with the IYA 2009 events of Sri Lanka.