Wednesday, November 27, 2013

Travel Back In Time To The Ice Age - How To View A Galaxy

You can see a galaxy in the sky and don't even need a telescope or binoculars. The attempt should be made on a clear, moonless night. In addition, it would help to travel out into the country, away from city lights, shopping malls, and other sources of "light pollution." This is because faint celestial objects are "washed out" by such sources and, as a result, will not be visible. Additionally, the scattering of light makes it difficult to distinguish faint objects from the background of the sky.It may be helpful to refer to a popular magazine, such as "Sky and Telescope" or "Astronomy" for charts of star positions with respect to your location and the time of year, as well as time of night. Look towards the constellation of Andromeda, near the legs of Pegasus. This leads you to "The Andromeda Galaxy," also known as M31, one of the most distant objects that can be seen without optical aid. It is visible as a faint patch of light, and is over 2 million light years from Earth. In other words, it is so far away that the light took 2 million years to travel to Earth. The image we see today was first generated when the Earth was nearing the end of the Pliocene Epoch and the Ice Age was beginning. In a sense, this view lets us "travel back in time!"While it is possible to see M31 with "the naked eye," binoculars or a small telescope will make the process easier. In particular, this is the case if you need to observe near a "light filled city" and can not travel out to the country. Such a sight is truly inspiring, and the observer gains an appreciation for the awesome beauty of the night sky.Below are the answers to common questions regarding this subject:

What is a light year?

A light year is not a unit of time (like an hour or year). Instead, it is a measure of distance: It is the distance that light will travel in one year. Light is a form of electromagnetic radiation, and travels at 186,282 miles per second. So, light will travel 5,865,696,000,000 miles in a year. This is very, very far! One can also come up with a unit known as a "light minute:" The sun is about 93 million miles from Earth, and light from it takes about 8 minutes to travel to Earth. This means that the sun is 8 "light minutes" away. That is, if the Sun "went out," we would not know about it for 8 minutes!



Why is the galaxy called M31? What does the "M" stand for?

Many celestial objects are named with an "M" followed by a number. The "M" stands for Messier and comes from the name of a French astronomer, Charles Messier, who put together catalog of celestial objects in the 18th Century. Messier successfully discovered about 20 comets and put together the catalog to record celestial objects easily mistaken for actual comets. Other examples of "Messier Objects" include:

M1,"The Crab Nebula," found in the constellation of Taurus. It is also the site of a supernova remnant.

M13,"The Great Cluster," is a globular star cluster found in the constellation of Hercules.

M42, "The Great Nebula," is also known as "The Orion Nebula" and is one of the brightest celestial objects in the northern hemisphere. It can be seen in the "sword" of the bright constellation of Orion, the hunter.



What is a galaxy?

A galaxy is a system of about 100 billion stars, all held together by mutual gravitational attraction. It is truly an "island" in space, and the stars in a particular galaxy are "isolated" from stars in the next galaxy by extreme distance. The Andromeda galaxy is "close" to us by galactic standards, and is in our "local group" of galaxies.


Kevin Matthews is currently employed in the Information Technology Industry and has an interest in Astronomy. Additional information regarding Skywatching, Nature, and Crafts can be found on the following website: [http://www.bestdes

Related Posts :

Posted by at

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)