| Star Chart Notes |

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All the Brightest Stars
The hemispheres on the chart show the night sky as
it appears from earths North and South poles. All 2,844 stars, plus nebulae, and star
clusters, can be seen with the unaided eye. Bright stars are assigned large symbols but
small numerical designations: dim stars have small symbols but large numerical designations. |
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The Greek Alphabet
Greek letters on the chart indicate a stars level of
apparent brightness compared with other stars within its constellation (alpha usually appears
as the brightest, beta the next brightest, and so on). |
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Precession
The earth wobbles, like a spinning top. It takes about
26,000 years for a Pole to realign with a given star, yet this precession is enough to change
the stars apparent position, requiring updated star charts every 50 years. For example,
on northern sky star charts of 1950 three stars known as the Kids were located just above
the meridian designated V. This new chart, representing the sky in the year 2000, places them
below that line.

The Milky Way
Individual stars visible to the naked eye are our
closest galactic neighbors. The Milky Way, a misty river of stars that flows across the
heavens, is an edge-on view of our home galaxy, which includes a few hundred billion stars.
Andromeda, the nearest spiral galaxy like our own, is 2.5 million light-years away.
©1997 National Geographic
Society. All rights reserved.
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