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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.
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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 and a good place to start is a website like Kokopeli High School Academy - free evaluation and a 75% success rate.


InboxAstronomy: Our Sun Came Late to the Milky Way's Star-Birth Party Our Sun missed the stellar "baby boom" that erupted in our young Milky Way galaxy 10 billion years ago. During that time the Milky Way was churning out stars 30 times faster than it does today. Our galaxy was ablaze with a firestorm of star birth as its rich reservoir of hydrogen gas compressed under gravity, creating myriad stars. But our Sun was not one of them. It was a late "boomer," arising 5 billion years later, when star birth had plunged to a trickle.
Astronomers compiled this story of our Milky Way's growth from studying galaxies similar in mass to our galaxy, found in deep surveys of the universe. Stretching back in time more than 10 billion years, the census contains nearly 2,000 snapshots of Milky Way-like galaxies. The analysis comprises the most comprehensive multi-observatory galaxy survey yet, and includes data from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), taken with NASA's Hubble Space Telescope.


APOD:The Great Crater Hokusai
Image Credit: NASA, Johns Hopkins Univ. APL, Arizona State Univ., CIW

Explanation: One of the largest young craters on Mercury, 114 kilometer (71 mile) diameter Hokusai crater's bright rays are known to extend across much of the planet. But this mosaic of oblique views focuses on Hokusai close up, its sunlit central peaks, terraced crater walls, and frozen sea of impact melt on the crater's floor. The images were captured by the MESSENGER spacecraft. The first to orbit Mercury, since 2011 MESSENGER has conducted scientific explorations, including extensive imaging of the Solar System's innermost planet. Now running out of propellant and unable to counter orbital perturbations caused by the Sun's gravity, MESSENGER is predicted to impact the surface of Mercury on April 30.


APOD:M46 Plus Two
Image Credit & Copyright: Denis Priou

Explanation: Galactic or open star clusters are young. These swarms of stars are born together near the plane of the Milky Way, but their numbers steadily dwindle as cluster members are ejected by galactic tides and gravitational interactions. In fact, this bright open cluster, known as M46, is around 300 million years young. It still contains a few hundred stars within a span of 30 light-years or so. Located about 5,000 light-years away toward the constellation Puppis, M46 also seems to contain contradictions to its youthful status. In this pretty starscape, the colorful, circular patch above and right of the center of M46 is the planetary nebula NGC 2438. Fainter still, a second planetary nebula, PK231+4.1, is identified by the box at the right and enlarged in the inset. Planetary nebulae are a brief, final phase in the life of a sun-like star a billion years old or more, whose central reservoir of hydrogen fuel has been exhausted. NGC 2438 is estimated to be only 3,000 light-years distant, though, and moves at a different speed than M46 cluster members. Along with its fainter cohort, planetary nebula NGC 2438 is likely only by chance appearing near our line-of-sight to the young stars of M46.





Iris Nebula
- Image by Ricky Leon Murphy.

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

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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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