Life of a Star Project:


Polaris



  I chose to study the life of the star Polaris.  Polaris is a very famous star; it is also known as the Pole Star, or the North Star, because of its coincidental position, on the Earth's axis of rotation and directly above its north pole.  Because it is on the axis of rotation, it appears never to move in the night sky; it always points north, so it is of tremendous aid to travellers and navigators with no other landmarks by which to navigate.

  Polaris, incidentally, was not always the "North Star".  Earth's axis actually rotates in a circle, whose radius would be 23 degrees, were it traced out in the sky.  Earth completes one rotation through this circle every 26,000 years or so, so we aren't likely to notice any significant change in our lifetimes, but the target of the Earth's axis has changed significantly throughout civilization, giving rise to a whole series of "North Stars".  Kochab, in the tail of Ursa Minor, held this title some 2,000 years ago; Thuban, in the constellation Draco was known as the North Star some five millenia ago.  14,000 years ago, at roughly the opposite side of the axial rotation, Vega, in the constellation Lyra, was known as the North Star.


Here are some links to more information about Polaris:

  How it was born: How Polaris originally formed

  What it is like now: Where it is in the sky, what materials it burns, and more

  How it will 'die': How and when it will cease to exist as a star

  Links and Bibliography: Links to other sites containing information about Polaris