ASTR1010L &
ASTR1020L
DEEP SKY HUNT
(HARD)
LAB #4
The purpose of this lab is to once again locate and observe
deep sky objects, just like in Lab #3.
The difference is that in this lab, the objects are much harder to find (much harder!). You will have to find only two of these objects to get credit for the lab, but don't underestimate the task. You will have to
practice finding these objects during the training period, otherwise you will
not stand a chance of finding them during the testing phase. Unlike Lab #3, the objects in this lab are mostly galaxies and planetary nebulae (there are a few globular clusters, thought).
Galaxies are vast systems of hundreds of billions of stars (at least the
bigger ones), but they are so far away that they will look like faint white smudges
in the telescope. Planetary
nebulae are the ejected outer envelopes of burned out stars and they, too, will
look like faint smudges. You might
want to do a Google search on these objects to see what they look like through
large telescopes. Of course, you won't see them that way because of the size of our telescopes and the fact that cameras don't work the way the eye does, but it might be fun to compare what you see with what big telescopes can image.
One important trick in finding these objects is to AVOID THE MOON or nights when the Moon is close to full. The Moon is so bright that if it is in the same general area of the sky that you are looking at, there is no way you will find faint galaxies or planetary nebulae. For instance, M65 and M66 are in the
constellation Leo and the Moon passes through Leo over the course of a few
nights every month. If the Moon is
anywhere near Leo, you will not be able to find either galaxy. Always look for these objects with the low power eyepiece and be sure to use the 10-inch Dobsonians because of its greater light-gathering capability.
Light-gathering goes as the area of the primary mirror (or lens if you are using a refracting telescope), th area goes as the size squared, so a 10-inch Dobsonian has 1.5625 times more light-gathering capability than an 8-inch telescope. (102
/ 82 = 1.5625).
In this lab, you will be asked to find two examples from the list below. You will find the first object, point
the telescope to it and then show the instructor that you have indeed found
it. After the instructor has seen
it, you will move to the next object and repeat the process. Since these objects can not be seen with the naked eye (and not even in the telescope finder!!), you will have to try to find stars near them and then offset the telescope from the stars. Use your star atlas wisely and try this lab only on the clearest, moonless nights. Don't get frustrated, because this lab is - by far - the most difficult one of all. Choose 2 objects from
the following list:
|
Name |
RA |
Dec |
Magnitude |
Size |
Object Type |
|
|
|
|
|
|
|
| M33 | 01h 31m 02s
|
+30o 24' 15"
|
5.7 | 73' x 45' | Spiral Galaxy |
|
M81 |
09h 55m 36s |
+69¡ 04¢ 00² |
6.9 |
17' |
Spiral Galaxy |
|
M65 |
11 18 54 |
+13 05 00 |
9.3 |
9'
|
Spiral Galaxy |
|
M66 |
11 20 12 |
+12 59 00 |
8.9 |
8'
|
Spiral Galaxy |
|
NGC2392 |
07 29 12 |
+20 55 00 |
9.2 |
15' |
Planetary Nebula |
|
NGC3242 |
10 24 32 |
-18 38 00 |
7.8 |
16' |
Planetary Nebula |
|
NGC2903 |
09 32 12 |
+21 30 00 |
9.0 |
10'
|
Spiral Galaxy |
|
NGC2403 |
07 36 54 |
+65 36 00 |
8.5 |
20¢ |
Elliptical Galaxy |
|
M104 |
12 40 00 |
-11 37 00 |
8.0 |
9'
|
Spiral Galaxy |
|
M97 |
11 14 48 |
+55 01 00 |
9.9 |
3'
|
Planetary Nebula |
| M57 | 18 53 36
|
+33 02 00
|
8.8 | 1.4' | Planetary Nebula |
| M56 | 19 16 36
|
+30 11 00
|
8.3 | 8.8' | Globular Cluster |
| M27 | 19 57 27
|
+22 35 01
|
7.4 | 8' | Planetary Nebula |