The Great Cosmic Easter Egg Hunt

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Purpose:
The purpose of this exercise is to become familiar with the sky in general, and several classes of objects in particular.

Procedure:

1. Here is a list of objects that can be found on these photographs:
   

   Object Name	Right Ascension	Declination	Apparent Magnitude	Approximate Angular Size arcminutes	Distance from Earth (pc)
   Orion Nebula (M42, NGC 1976)	05h, 35m	-05	3.0	60	490
   Hercules Cluster (M15, NGC 6205)	16h, 42m	+36	5.9	17	1.02X104
   Andromeda (M31, NGC 224)	00h, 42m	+41	4.4	100	8.9X105
   Eagle Nebula	18h, 19m	-14	6.4	25	2100
   The Pleiades	3h, 47m	+24	1.6	110	120
   M101, NGC 5457	14h, 03m	+54	8.2	30	8.2X106
   M55, NGC 6809	19h, 40m	-31	7.0	19	5400

2. For each object,
   1. Write the name of the object in the appropriate row
   2. Draw a sketch
   3. Identify the type of object from the following list
      • Bright Nebula: looks like a cloud (because it is a cloud in space). Stars are born in nebulae.
      • Globular Cluster: spherical group of about 1 million (10⁶) stars. Distinct from stars because rather than having fuzzy edges, it has edges made of lots of dots.
      • Open Cluster: loose cluster of a few hundred-few thousand nearby stars.
      • Spiral Galaxy: In 3-D, a spiral galaxy looks much like a frisbee, but depending on which way you look at it, it might be a circle, an ellipse, or a relatively thin line.

Questions:

1. Describe each of the object types as far, farther, or farthest away.
   • Bright nebula:
   • Globular cluster:
   • Open cluster:
   • Spiral galaxy:
2. Do you think that the types of objects you described as only 'far' exist at the 'farthest' distances as well? If so, why can't we see them?

Definitions and Fun Facts:

M (as in M31) stands for Messier, an early comet hunter, who was annoyed by the fuzzy, stationary objects in the sky which he might easily confuse with comets. So he made a list of stationary fuzzy objects. The Messier objects are the brightest extended objects in the northern sky other than planets.
NGC stands for New General Catalogue - now 100 years old - of extended objects.
Right Ascension and Declination are the coordinates of the sky, much like longitude and latitude on Earth
Apparent Magnitude is an indication of how bright an object appears to be. Apparent Magnitude runs backwards so that low numbers are brighter objects (the Sun has apparent magnitude = -26) and high numbers are fainter objects.
One degree is 60 arcminutes (60'). The Sun and the moon are 30' in angular size.
1 pc = one parsec = 3.26 light years = 2X10¹³ miles. The nearest star is 1.3 pc away.