Clarkson Integrator

Issue date: 1/21/08 Section: Features

Media Credit: Aaron Fetterman Jan Wojcik and Ben Brown-Steiner peer at the moon as it shines brightly over CAMP during one of the weekly meetings of the Clarkson Stargazers.

The moon will drown out most of the sky this week. This will make the two comets, and any other dimmer objects, very difficult to see. On Tuesday, the moon will be in the sky for the entire night. There will only be thirteen minutes in which both the sun and the moon will be below the horizon, in fact.

This leaves very little to see in the sky, besides the moon and the brightest of the stars. Lucky for us, Orion is front and center, and very bright. Orion is the constellation that I use to orient myself during stargazing. It is a good constellation to demonstrate the angular method of measurement.

The stars in our sky stay, with slight exception, constant. While stargazing, it is good to visualize all of the stars as if they were on one celestial sphere. When thinking about the size and dimensions of our universe, however, the celestial sphere just gets in our way.

For instance, the three stars that make up Orion's Belt, from left to right, are called Alnitak, Alnilam, and Mintaka. Alnitak is a triple star that is 800 light-years away from earth; Alnilam is a blue-white supergiant located 1300 light-years away from us; Miktaka is a multiple star located 800 light-years away.

However, from an observer on earth, these three stars will, barring a galactic catastrophe, always appear to be the same distance apart, and in the same spot, in the sky. This is why the angular method of measurement is so useful to us earth dwellers.

The Babylonians first utilized and defined this system. We use many of the definitions they established every day. The Babylonians observed that the sun takes approximately 365 days to travel full circle in the sky. As such, they defined one degree as the distance the sun appeared to move each day, in relation to the background stars. Subsequently, they defined that there are 360 degrees in a circle.

It is still used today, because this method is one of the simplest and most reliable methods for measuring distances in the sky. The units are degrees, minutes, and seconds, like any other angular measurement.

Continued...

Page 1 of 2 next >

Article Tools