At sunset, on Saturday, a giant moon rose in the east. It was the biggest and brightest one of 2009, which has certainly amazed even seasoned observers. Earth, the moon and the sun are all bound together by gravity, which keeps us going around the sun and keeps the moon going around us as it goes through phases. The moon makes such a trip around us every 29.5 days, but the orbit is not a perfect circle.

One portion is 50,000 m closer to our planet than the farthest part and, on Saturday night, the moon was at perigee, the closest point to us on this orbit. Therefore, it will appear 14% bigger in our sky and 30 percent brighter than other full moons during 2009, according to NASA. It's interesting to see that a similar turn of events happened in December, making that month's full moon the largest of 2008.

As the moon's position affects tides, they will be higher too, as the moon gets closer. Tides like these are called perigean tides, because they occur when the moon is at or near perigee. A full moon rises right around sunset, no matter where you are.

However, because of the mechanics of all these processes, the moon is never truly 100 percent full. For that to happen, all three objects have to be in a perfect line, and when that rare circumstance occurs, there is, of course, a total eclipse of the moon. Even as we speak, the moon is moving away, by about 4 centimeters an year. Eventually, this drift will force it to take 47 days to circle our planet.

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A video from the International Space Station

Link: Inside the ISS

China has officially started construction of a Five-hundred-meter Aperture Spherical Telescope (FAST), which when completed, would be the world’s largest radio telescope.radio-telescope2-199x300 China to build world’s largest radio telescope

The dish-like telescope, as large as 30 football fields, will stand in a region of typical Karst depressions in Guizhou Province in China, when it’s completed in 2013.

Chinese scientists and officials selected Dawodang, Pingtang County as the site, where a Karst valley will match the shape of the huge bowl-like astronomical instrument.

The sparsely populated, underdeveloped region will provide a quiet environment to ensure the electromagnetic waves, the crucial requirement of operation, are not interrupted by human activities.

According to the National Astronomical Observatory (NAO), the major developer of the program, the facility will greatly improve China’s capacity for astronomical observation.

FAST’s main spherical reflector will be composed of 4,600 panels. Its observation sensitivity will be 10 times more powerful than the 100-m aperture steerable radio telescope in Germany.
Its overall capacity will be 10 times larger than what is now the world’s largest (300 m) Arecibo radio telescope developed by the United States, according to Nan Rendong, the chief scientist of the project and an NAO researcher.

“The project, costing more than 700 million yuan (102.3 million US dollars), will allow international astronomers and scientists to discover more of the secrets of the universe based on cutting-edge technologies,” said Zhang Haiyan, an NAO official in charge of construction.

FAST could also be a highly sensitive passive radar to monitor satellites and space debris, which would be greatly helpful for China’’s ambitious space program.

The telescope could also help to look for other civilizations by detecting and studying communication signals in the universe. (ANI)

Fresh News 

The full moon on the 11th of December was the biggest and brightest of 2008.

Did you know... The full moon on the 11th of December was the biggest and brightest of 2008. The above picture shows two full moons taken through a 6-inch reflector telescope, six months apart. The full moon this month was found to be about 30 percent brighter and 14 percent larger than the earlier full moons this year. The reason for this celestial wonder? Because the moon was closest to us between 11th and 12th December. The nearest point (Perigee) and farthest point (Apogee) on Moon’s orbit differs by approximately 55,000 Kms ! This could be a simple photography project that students and amateur astronomers can take up. Take full moon photos every month for one year. It will show the changes in the moon size due to its elliptical orbit round the earth. Photo Credit: Naveen L Nanjundappa, Vice President, Bangalore Astronomical Society www.bas.org.in

Deccan Herald

Explanation: If you took a picture of the Sun at the same time each day, would it remain in the same position? The answer is no, and the shape traced out by the Sun over the course of a year is called an analemma. The Sun's apparent shift is caused by the Earth's motion around the Sun when combined with the tilt of the Earth's rotation axis. The Sun will appear at its highest point of the analemma during summer and at its lowest during winter. Today, the Winter Solstice day in Earth's northern hemisphere, the Sun is at the bottom of the analemma. Analemmas created from different latitudes would appear at least slightly different, as well as analemmas created at a different time each day. This particular analemma was built up by 46 separate Sun photographs taken during 2003 in Athens, Greece. Pictured in the foreground of this composite image are pillars called the Porch of Maidens, part of the ancient Erechtheum which was completed in 407 BC.

Via Apod

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