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Star hopping to the Andromeda Galaxy (M31) is a snap, since all the stars needed to do so are visible to the naked 
eye.

 

Star hopping will take some getting used to and objects that don’t have stars near them that are visible to the naked 
eye are challenging.  One such object is M57 (Figure 5-2), the famed Ring Nebula.  Here's how to find it: 

1. Find the constellation of Lyra, a small parallelogram visible in the summer and fall months.  Lyra is easy to pick

out because it contains the bright star Vega.

2. Start at the star Vega—Alpha (

D

) Lyrae—and move a few degrees southeast to find the parallelogram. The four

stars that make up this geometric shape are all similar in brightness, making them easy to see.

3. Locate the two southernmost stars that make up the parallelogram—Beta (

E

) and Gamma (

J

) Lyra.

4. Point about halfway between these two stars.

5. Move about 

½

° toward Beta (

E

) Lyra, while remaining on a line connecting the two stars.

6. Look through the telescope and the Ring Nebula should be in your field of view.  The Ring Nebula’s angular

size is quite small and difficult to see.

7. Because the Ring Nebula is rather faint, you may need to use “averted vision” to see it.  “Averted vision” is a

technique of looking slightly away from the object you’re observing.  So, if you are observing the Ring Nebula,
center it in your field of view and then look off toward the side.  This causes light from the object viewed to fall
on the black and white sensitive rods of your eyes, rather than your eyes color sensitive cones.  (Remember that
when observing faint objects, it’s important to try to observe from a dark location, away from street and city
lights.  The average eye takes about 20 minutes to fully adapt to the darkness.  So always use a red-filtered
flashlight to preserve your dark-adapted night vision).

These two examples should give you an idea of how to star hop to deep-sky objects.  To use this method
on other objects, consult a star atlas, then star hop to the object of your choice using “naked eye” stars.

Figure 5-2 

Содержание FirstScope 21024

Страница 1: ...F Fi ir rs st tS Sc co op pe e I In ns st tr ru uc ct ti io on n M Ma an nu ua al l M Mo od de el l 2 21 10 02 24 4...

Страница 2: ...General Observing Hints 7 The Celestial Coordinate System 8 Motion of the Stars 9 CELESTIAL OBSERVING 10 Observing the Moon 10 Lunar Observing Hints 10 Observing the Planets 10 Observing Deep Sky Obje...

Страница 3: ...and easy set up Take time to read through this manual before embarking on your journey through the Universe It may take a few observing sessions to become familiar with your telescope so you should ke...

Страница 4: ...4 Figure 1 1 1 Focuser 6 Arm 2 Secondary Diagonal Mirror inside 7 Tube End 3 Optical Tube 8 Primary Mirror inside 4 Lock Nut 9 Focus Knob 5 Base 10 Eyepiece 10 9 8 7 6 5 4 3 2 1...

Страница 5: ...er see the section on Calculating Magnification The eyepiece fits directly into the focuser To attach the eyepieces 1 Make sure the thumbscrews are not protruding into the focuser tube Then insert the...

Страница 6: ...ll enjoy a telescope that is relatively compact and portable A Newtonian Reflector telescope offers such impressive light gathering characteristics you can take a serious interest in deep space astron...

Страница 7: ...t you are observing To calculate the actual field of view divide the apparent field of the eyepiece supplied by the eyepiece manufacturer by the magnification In equation format the formula looks like...

Страница 8: ...rth and separates the northern celestial hemisphere from the southern Like the Earth s equator it bears a reading of zero degrees On Earth this would be latitude However in the sky this is referred to...

Страница 9: ...use the sunlight during the day washes out the starlight However part of this circular motion of stars in this region of the sky can be seen by setting up a camera on a tripod and opening the shutter...

Страница 10: ...see the moons of Jupiter as they orbit the giant planet Saturn with its beautiful rings is easily visible at moderate power Planetary Observing Hints y Remember that atmospheric conditions are usually...

Страница 11: ...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 sev...

Страница 12: ...necting the two stars 6 Look through the telescope and the Ring Nebula should be in your field of view The Ring Nebula s angular size is quite small and difficult to see 7 Because the Ring Nebula is r...

Страница 13: ...ound around major urban areas LPR filters enhance deep sky viewing from light polluted areas by blocking unwanted light while transmitting light from certain deep sky objects You can on the other hand...

Страница 14: ...ted If moisture condenses on the inside of the optics remove the accessories from the telescope Place the telescope in a dust free environment and point it down This will remove the moisture from the...

Страница 15: ...osed on the primary mirror Figure 6 2 If the primary mirror is not centered in the secondary mirror adjust the secondary mirror screws by alternately tightening and loosening them until the mirror is...

Страница 16: ...Length 300mm Focal Ratio f 4 Optical Coatings Coated Eyepieces 1 25 Barrel 20mm 15x 4mm 75x Apparent FOV 20mm 25 and 4mm 33 Angular Field of View w 20mm eyepiece 1 7 Linear FOV w 20mm ft 1000yds m 10...

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