More M13's
I was in a funk. I had looked forward to the November new moon event. After a Spring and summer with far too many cloudy days, we desert dwellers were due our allotted clear nights! But light cirrus clouds spoiled the November sky transparency and our enthusiasm.
I had observed a couple of hours when I walked over to my friend Dee Friesen's setup. He was working on The Albuquerque Astronomical Society (TAAS) 200 list and had located NGC 55. He invited me to have a look. The scope was pointed almost at the horizon. Instead of black sky with bright jewel-like stars, I looked at an atmosphere-dense, mud-gray background with stars so dim as to be faint fuzzies themselves.
"It is between the two stars in the center of the field." I moved the scope so that the stars were on the left side of the field, then to the right. I moved my eye far to the left and right. "I see nothing" I said. "It's there." he replied.
I walked back to my van and began packing my stuff. Alan Scott walked over and inquired about my early departure.
"I have lost my mo-jo, Alan" I said. "It is no fun searching for faint galaxies under these conditions."
Alan sympathized with my depression. He said, "you know, we need more M13's."
Driving back to Albuquerque, I thought about what Alan said. Maybe it wasn't so much the weather as the choice of objects we have made.
One is first introduced to the Messier objects. For a beginner, the Messier objects can be challenging but afford exciting views of the universe. They continue to delight advanced astronomers but, in the end, there are only 110 of them.
You are afraid they will become like Beatles songs, played so much they lose their magic.
So you try to add variety. For us in TAAS, there is the aforementioned TAAS 200 list. Maybe a quarter of the objects in that list are jewels but most are forgettable due to dimness.
People offer the Hershel 400. Now there are dim objects. Add the ARP list and you have objects hardly distinguishable from a 14th magnitude star.
With these choices, it is easy to get into a funk.
What is needed is a new Messier list. There are, after all, 2 Hershel lists. The second list needs the name, What-Messier-Should-Have-Seen list, or, simply Messier II.
I would venture to offer some points on choices for the list.
Magnitude
You have surely been assailed by some fellow insisting you look at the 12th magnitude galaxy in his 8 inch reflector. You see perhaps a smoky pinpoint. But your collegue plies you with elaborate descriptions of "striated arms on both sides of the face, each arm having several outward facing spurs...". Some drink the Koolaid and go to others talking of striated arms. Most of you, however, maintain a healthy scepticism toward such fancifulness.
The little dumbell nebula, M76, is 10th magnitude. It is diminutive in smaller scopes but has some life with higher magnitude in bigger telescopes. Go to an 11th magnitude object and you are pressed to find a reason to continually return to it.
There are exceptions but anything beyond 10th magnitude should not be on Messier II list.
Location
The sculptor galaxy may be a great Messier II list candidate for Key West residents, not for astronomers in upper Michigan peninsula.
There are presumably sufficient objects in constellations that are visible for months in the Northern Hemisphere. I suggest that a Messier II be restricted to choices in those constellations.
In New Mexico we are fortunate to be able to see Omega Centauri for a time each Spring. That object should not however be on Messier II because of the short duration for viewing.
Color
When you show others Hershel's garnet star, inevitably someone claims another star as even redder. People like color. Mention carbon stars to David Frizzell and watch his eyes light up.
Dee Friesen likes binary stars because they show color variation. There is a binary star in the original Messier list, why not in Messier II?
Quirkiness
M46 is an open cluster in Puppis. Star hopping to the object is difficult. One might prefer the easier-to-find Auriga open clusters. What makes M46 special is the embedded planetary nebula. This unusual aspect favors it over other clusters.
Quirkiness makes an object stick in memory. I don't forget M46 because of an inadvertant trick Greg Dillon pulled on me. Greg pushed the magnification of M46's planetary to 1000x in his 25" reflector. It appeared to be M57 in a December sky.
Greg likes another object, the hockey stick galaxy, NGC 4656, which indeed has a weird and unforgettable hockey stick shape.
Sometimes Good
There are objects which mostly look like blobs, but on a special night, shine. I think of a night's viewing with Eric Edwards at Chaco canyon. We had the scope on M101. Maybe we got a whiff of ancient Anazasi peyote pipe but both of us saw a sparkly face-on galaxy with spiral arms. A half hour later I went back and saw what subsequently I normally see, a blob. Since then I go to M101 often hoping it will fire up again.
Like Cepheid variable stars, some objects rise to prominence and fade. That trait makes them stick out.
List Size
Locating 400 Hershel objects is daunting. Even the TAAS 200 objects can take years to locate. 100 objects seems the right number for the Messier II list.
Call To Arms
Our club members and astronomers in general amaze me. Dedication abounds. Those who created the TAAS 200 list showed persistence and brilliance. The list that I propose is more limited in scope and location than the TAAS 200. I do not have the knowledge to create a Messier II list on my own. I need assistance. Will you help?
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