Monday, November 24, 2008

Galaxies

Was looking at some astronomy sites and stumbled on this Google Earth community. The pictures captivated my attention and I had to download some for my viewing pleasure.


1) Firstly this is our world, Sun and her planets. We are Earth, the only place where life exists.




Picture of our solar system & planets scaled to size. Earth (so small) is third from sun.


2) Deep sky objects - the other world out there. The cosmos is so mysterious and scary - galaxies, nebulas, etc.etc. To my naked eye,the night sky is just the moon and twinkling stars. The universe is so very complex.



Pictures by NASA space telescope.




NGC 7331 sits about 50 million light-years from Earth and has been billed as a twin of our own Milky Way galaxy because of its similar mass, star count and spiral arm shapes. Skywatchers Paul Mortfield and Dietmar Kupke recorded this view of NGC 7331 on Oct. 4, 2005 during a nightly observing program run by Kitt Peak. This image was featured as space.com's Image of the Day.






Credit & Copyright: Tony Hallas

One of the brightest galaxies in planet Earth's sky and similar in size to the Milky Way, big, beautiful spiral M81 lies 11.8 million light-years away in the northern constellation Ursa Major. This remarkably deep image of the region reveals details in the bright yellow core, but at the same time follows fainter features along the galaxy's gorgeous blue spiral arms and sweeping dust lanes. Above M81 lies a dwarf companion galaxy, Holmberg IX, sporting a large, pinkish star-forming region near the top. While M81 and Holmberg IX are seen through a foreground of stars in our own Milky Way galaxy, they are also seen here through a much fainter complex of dust clouds. The relatively unexplored clouds are likely only some hundreds of light-years distant and lie high above our galaxy's plane. Scattered through the image, especially at the the right, the dust clouds reflect the combined light of the Milky Way's stars and have been dubbed integrated flux nebulae.



3) The Orion constellation - one of the most visible group of stars, can be seen from Nov to Jan. I will be looking out for it. In KL the orientation of the stars will be different from this picture because of different latitudes.

Credit & Copyright: Wally Pacholka (Astropics.com)

Explanation: Welcome to The World At Night. Sharing the night sky seen around the world, this view from Monument Valley, USA includes a picturesque foreground of famous buttes. Buttes are composed of hard volcanic rock left behind after water eroded away the surrounding soft rock. The two buttes on the image left are known as the Mittens, while Merrick Butte is on the right. Recorded just last week, planet Mars is at the left of the skyscape, a glowing beacon of orange that is the brightest object in the frame. To the right of Mars lies the constellation of Orion. Betelgeuse is the reddish star near the center and the Belt of Orion and the Orion Nebula are farther right. Finally, the bright blue star Rigel appears above Merrick Butte in this stunning view of The World At Night. NASA-APOD






Credit: Digitized Sky Survey, ESA/ESO/NASA FITS Liberator Color Composite: Davide De Martin (Skyfactory)

Explanation: Alnitak, Alnilam, and Mintaka, are the bright bluish stars from east to west (left to right) along the diagonal in this gorgeous cosmic vista. Otherwise known as the Belt of Orion, these three blue supergiant stars are hotter and much more massive than the Sun. They lie about 1,500 light-years away, born of Orion's well-studied interstellar clouds. In fact, clouds of gas and dust adrift in this region have intriguing and some surprisingly familiar shapes, including the dark Horsehead Nebula and Flame Nebula near Alnitak at the lower left. The famous Orion Nebula itself lies off the bottom of this star field that covers an impressive 4.4x3.5 degrees on the sky. The color picture was composited from digitized black and white photographic plates recorded through red and blue astronomical filters, with a computer synthesized green channel. The plates were taken using the Samuel Oschin Telescope, a wide-field survey instrument at Palomar Observatory, between 1987 and 1991.more: NASA-APOD






Credit & Copyright: Gemini Observatory, AURA, NSF

Explanation: Why are bullets of gas shooting out of the Orion Nebula? Nobody is yet sure. First discovered in 1983, each bullet is actually about the size of our Solar System, and moving at about 400 km/sec from a central source dubbed IRc2. The age of the bullets, which can be found from their speed and distance from IRc2, is very young -- typically less than 1,000 years. As the bullets rip through the interior of the Orion Nebula, a small percentage of iron gas causes the tip of each bullet to glow blue, while each bullet leaves a tubular pillar that glows by the light of heated hydrogen gas. Pictured above, the Orion bullets were captured in unprecedented detail by the adaptive optics technology of the Gemini North telescope. M42, the Orion Nebula, is the closest major star forming region to us and filled with changing dust, gas, and bright stars. The Orion Nebula, is located about 1,500 light years away and can be seen with the unaided eye toward the constellation of Orion.







Two images of Orion :-
left picture taken under normal visible light.
right picture taken with an Infrared telescope. The 'orange coloured' parts are frozen gas.




Light has wavelengths. We only can see the spectrum (or rainbow colours) but Infrared telescopes can 'see' the 'invisible' wavelength and translate it into colours.

Look out for the above group of stars (left picture), at night east direction, now till January 09. I havent done much stargazing since my neighbour's tree grew and blocked my eastward view. His tree is my arch-enemy!!


Orion is also known as "The Hunter". Top 2 stars are shoulders, middle 3 stars his belt, 1 star below belt is the tip of his sword, and bottom 2 stars his knees.
Names of Stars in Orion (left to right):-
Shoulders - Betelgeuse (reddish) & Bellatrix.
Belt stars - Alnitak, Alnilam & Mintaka.
Sword - Hatsya.
Knees - Saiph & Rigel (brightest).
The Bible mentions Orion three times:-
Job 9:9 :- He is maker of the Bear and Orion.
Job 38:31 :- Can you loosen Orion's belt?
Amos 5:8 :- He who made the Pleiades and Orion.
(Pleiades is another group of stars also known as the 7 sisters)