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Star Hopping
One convenient way to find deep-sky objects is by star hopping. Star hopping is done by using bright stars to
"guide" you to an object. For successful star hopping, it is helpful to know the field of view of your telescope.
If you’re using the standard 20mm eyepiece with the FirstScope telescope, your field of view is approximately 2.7º.
If you know an object is 3º away from your present location, then you just need to move about one field of view.
If you’re using another eyepiece, then consult the section on determining field of view.
Some helpful tools and information for Star Hopping:
y
Star Charts (Maps) / Star Atlas – a necessary map of the stars which is somewhat like a roadmap for cars.
y
Knowledge – know the relative position of bright stars and constellations which are starting point for star
hopping. You can gain this knowledge from various books available.
y
Finderscope – helpful tool. A finderscope is a small, low power, wide field telescope used to aim a larger
telescope at a remote object. You can see more stars with a finderscope than you can with the naked eye.
y
Binoculars – a helpful tool in locating bright stars and searching an area you are looking for objects in. Can
be a substitute or supplement to a finderscope.
y
Books – several books are available solely on Star Hopping.
y
Measurement Guide – the approximate distances spanned with your hand held out at arms length. Your
index finger @ 1°, three fingers @ 3°, closed fist @ 10°.
Star hopping may seem difficult at first but through patience, determination, and practice you can learn this skill and
remember it forever. Listed below are directions for locating two popular objects.
The Andromeda Galaxy (Figure 5-1), also known as M31, is an easy target. To find M31:
1.
Locate the constellation of Pegasus, a large square visible in the fall (in the eastern sky, moving toward the
point overhead) and winter months (overhead, moving toward the west).
2.
Start at the star in the northeast corner—Alpha (
D
) Andromedae.
3.
Move northeast approximately 7°. There you will find two stars of equal brightness—Delta (
G
) and Pi (
S
)
Andromeda—about 3° apart.
4.
Continue in the same direction another 8°. There you will find two stars—Beta (
E
) and Mu (
P
) Andromedae—
also about 3° apart.
5.
Move 3° northwest—the same distance between the two stars—to the Andromeda galaxy.
Figure 5-1
