Observing at Skyhound



Home   Deep Sky   Shallow Sky   Comet Chasing   Observing Handbook   Meet the Skyhound   Contact

Palomar 2
Globular Cluster
RA: 04h46m05.9s Dec: +3122'51" (Auriga)
Integrated Visual Magnitude: 13.0
Angular Diameter: 2.2'
Distance: 90,000 ly
Distance from Galactic Center: 110,000 ly

Minimum requirements to detect: 14-inch? telescope under dark skies

The Palomar globular clusters are by nature faint.  Most are visible only in larger amateur instruments and many are not visible at all.  As these clusters go, Palomar 2 is a showpiece.  Yet even in the largest of amateur instruments it appears as little more than a round, very diffuse hazy spot.

Palomar 2 is unique in several ways.  How many other globular clusters do you know of in Auriga?  That's right -- there aren't any others!  Palomar 2 is an "outer halo" globular which lies much father from the center of our galaxy than most.  Most globulars lie within 20,000 light years of the galactic center, but Palomar 2 lies over 100,000 light years distant.  Although not the most distant known, Palomar 2 lies at a galactic longitude of 170o, nearly in the opposite direction of the galactic center as seen from our vantage point.  Because most globulars lie much closer in, they tend to be found in constellations such a Sagittarius and Ophiuchus.  When we look toward Auriga we are looking in the opposite direction of the galactic center where few globulars are found.

Another thing that makes Palomar 2 special is that it lies near the plane of our galaxy behind a veil of dust.  If it weren't for the dust between us and Palomar 2, it would appear over 1.2 magnitudes brighter.  If not for the intervening dust it probably would have been discovered much earlier and  perhaps given an NGC number.  In addition to blocking some of the light of the cluster stars the dust also makes it look much redder.  This is because more of the blue light is blocked than the red, changing the apparent color balance.

I had some difficulty finding Palomar 2 in my 18-inch f/4.5 because, as with many obscure objects, the coordinates I had were quite a bit off.  I did notice a round haze nearby and upon checking the DSS I discovered that this was indeed the globular.  Palomar 2 had long been mistaken for a galaxy (MCG +05-12-01) so this may be how it is plotted on your charts.  It is also listed in the Guide Star Catalog as the "star" GSC 02374-0153. 

Once I was certain I was looking at the globular I went back for a closer look.  It was visible at 97x as a very round hazy ball.  I noted that it looked "pretty cool" and that no stars were resolved.  Averted vision was necessary to see it clearly, but it wasn't that difficult to see.  At 270x it looked a bit like a faint telescopic comet.   I found very few visual observations of this globular so I can only estimate the minimum aperture to see it.  Those with 12-inch or smaller scopes should have a try at it.  If you do glimpse it you can count yourself in a select group. 

Palomar 2 is about 3o away from Iota Aur.  The larger circle is a 6x30 magnifying finder with an FOV of 5o.  The smaller circle is the eyepiece view circle drawn below.  Zenith is down.

Above is the view in an 18-ich at 94x.  The bright star on the right is below and to the left in the finder view.