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Welcome to Astronomy Online
A legally blind photographer/astronomer on disability so I use this site to contribute to society.


Last Updated: October 24, 2012 added graphics for the 88 constellations under Observation/The Night Sky.

Dorado

This site is a testament that even though I have a physical disability - legally blind - I can still do things that helps other people. I even have a new project: Astro-Drummer, a site dedicated to my other hobby.

I also have a new image gallery. I call it Second Site Image Gallery.

This is an educational website. It's never too late to learn astronomy, even for those who have not completed their primary (High School) education. A GED can get you in the door to college level courses.


InboxAstronomy: Hubble Survey Unlocks Clues to Star Birth in Neighboring Galaxy All stars are not created equal. They can vary in mass by over a factor of 1,000. Our sun is classified as a diminutive yellow dwarf. What's more, stars are not born in isolation, but inside giant molecular clouds of hydrogen. The question has been: what fraction of stars precipitate out of these clouds into clusters that contain blue giants, yellow dwarfs, and red dwarfs? It's like asking if all automobile manufacturers fabricate the same proportion of trucks, SUVs, sedans, and subcompacts. The best way to address the question is not to look around our Milky Way — which we are inside — but far out into space to the neighboring Andromeda galaxy, 2.5 million light-years away. Embedded in a sweeping Hubble Space Telescope mosaic of 117 million stars in the galaxy's disk are 2,753 star clusters. Hubble astronomers found that, for whatever reason, nature apparently cooks up stars like batches of cookies. There is a consistent distribution from massive stars to small stars. It is surprising to find that this ratio is the same across our neighboring galaxy (as well as inside our stellar neighborhood in the Milky Way), given the complex physics of star formation.


APOD:Milky Way with Airglow Australis
Image Credit & Copyright: Yuri Beletsky (Carnegie Las Campanas Observatory)

Explanation: After sunset on September 1, an exceptionally intense, reddish airglow flooded this Chilean winter night skyscape. Above a sea of clouds and flanking the celestial Milky Way, the airglow seems to ripple and flow across the northern horizon in atmospheric waves. Originating at an altitude similar to aurorae, the luminous airglow is instead due to chemiluminescence, the production of light through chemical excitation. Commonly captured with a greenish tinge by sensitive digital cameras, this reddish airglow emission is from OH molecules and oxygen atoms at extremely low densities and has often been present in southern hemisphere nights during the last few years. On this night it was visible to the eye, but seen without color. Antares and the central Milky Way lie near the top, with bright star Arcturus at left. Straddling the Milky Way close to the horizon are Vega, Deneb, and Altair, known in northern nights as the stars of the Summer Triangle.


APOD:Arp 159 and NGC 4725
Image Credit & Copyright: Stephen Leshin

Explanation: Pointy stars and peculiar galaxies span this cosmic snapshot, a telescopic view toward the well-groomed constellation Coma Berenices. Bright enough to show off diffraction spikes, the stars are in the foreground of the scene, well within our own Milky Way. But the two prominent galaxies lie far beyond our own, some 41 million light-years distant. Also known as NGC 4747, the smaller distorted galaxy at left is the 159th entry in the Arp Atlas of Peculiar Galaxies, with extensive tidal tails indicative of strong gravitational interactions in its past. At about a 100,000 light-years across, its likely companion on the right is the much larger NGC 4725. At first glance NGC 4725 appears to be a normal spiral galaxy, its central region dominated by the yellowish light of cool, older stars giving way to younger hot blue star clusters along dusty spiral outskirts. Still, NGC 4725 does look a little odd with only one main spiral arm.





Iris Nebula
- Image by Ricky Leon Murphy.

Astronomy Online is a personal resource of mine that is made public. Please enjoy the site.

ARCHIVED BLOG ENTRIES


How the Website is Organized:

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Observation - This section includes information on coordinate systems, constellations, objects visible in the night sky, and some images of the night sky of the northern and southern hemispheres.

Science - This section includes information on some of the basic science used in astronomy. There is information on the variety of tools used (like telescopes) as well as methods of using them. There is a mathematics primer, introduction to some physical processes, formulas used in astronomy, and information on computer use in Astronomy.

Solar System - As indicated, this section covers our Solar System and everything in it. It covers the Sun, planets, their moons, asteroids, comets and exotic objects like TNO's and Kuiper Belt Objects.

Stars - This section covers stars in our own galaxy. It covers the variety of stellar evolution paths. It also covers supernova, black holes, and some of the radiative processes in the interstellar medium.

Our Galaxy - This section covers our galaxy as well as some of the nearby galaxies in our own Local Group. It also covers galaxy evolution.

Cosmology - This section covers other galaxies and galaxies clusters. It also covers the big bang, relativity and dark matter.

Astrobiology - This section covers the relatively new field in astronomy - the possibility of life in our Solar System and the Universe. There is also information on some of the projects dealing with this - like SETI.

Exoplanets - This section covers the study of planets known to exist around other stars. It covers both amateur and professional involvement and shows you how you can get involved with the search as well.

Astrophotography - This section covers the fastest growing hobby of astrophotography. This section offers information and tips on photography and also features and Image Gallery.

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