Well go figure. I go back to work after two weeks off and what happens tonight? The storms of the last 7 days end, and the skies clear. I spent the evening getting ready to go back . . . . :''o(
Go figure. My entry tonight and I am going to expand upon it tomorrow (or on the next cloudy night as I hope to get some scope time tomorrow evening) is on Planetary Nebula. A Planetary Nebula or PN is my personal favorite object to chase down, though galaxies come a close second. Ninety-five percent of all stars in the universe will end their lives as a Planetary Nebula or PN as I call them. The other five percent, while they just go out with a "big bang" so to speak. In classifying PN's they have often been typized based on their appearance, using the Vorontsov-Velyaminov scheme which is as follows:
1. Stellar Image
2. Smooth Disk (a: brighter toward the center; b: uniform brightness; c: traces of a ring structure)
3. Irregular Disk (a: very irregular brightness distribution; b: traces of ring structure)
4. Ring Structure
5. Irregular form, similar to a diffused nebula.
6. Anomalous form
Now there seems to be additional classification being added with the addition of such wonderful instruments as the Hubble Telescope. There seems to more classification being added to PN's.
Bipolar Planetary Nebulae
Elliptical and Round Planetary Nebulae
The Cat's Eye Nebula
An interesting side note is that per the quote below, many of the PN's have rings and other shapes embedded in them. I guess I need to find out if there is an updated classification to PN's? Observations by the Hubble Space Telescope have revealed
that many planetary nebulae have multiple layers, and these are labeled as “shells”
“crowns” and “haloes." These multiple shell structures are the dynamical consequence of
interacting winds and of changing photoionization effects of the evolving central star. Other
minor morphological structures include arcs, rings, jets, ansaes, and multiple lobes and they
probably reflect the episodic and/or direction-changing nature of the stellar winds.
Are you interested in the above informaiton? I am sure some of you are more than aware of this, but others may not be. Here is a link to follow to learn or see more:
Planetary Nebula Overview
Hubble News Releases and PN's Not all are PN's but many are. Check out the 2008 number 4, a white dwarf with a ring around it . . . see above.
Hungry for more, and more cool Hubble images of these objects? Here's one last good site. Just remember, in our scopes visually, we'll never see these objects like this.
HST Archives Hubble Images PN's
I really like the image of M27 in there.
Interested in how they transform an image our eye would see at NASA into a colorful wonder? This article shows how they took images of Pease 1 or Planetary Nebula K648 in Messier 15 and transformed it.
PN K648 in M15 Image Process
As Pegasus comes up, if your up for a very difficult challenge in viewing a DSO, then PN K648 or Pease 1 can provide that for you.
Here is a Finder Chart for Pease 1
Observation Reports of Pease 1
Note some of these individuals have a ton of experience in the deep sky and there are a few reports using ten inch scopes, and I believe one using an 8 inch scope but most were using 14 inch or higher I believe (been awhile since I have read all the reports).
There's a greater challenge for much larger scopes but that can wait for one more month and if you have access to a very large telescope.
If you can't wait to see more, here is a list of the best seasonal planetary nebula by season for both hemispheres:
Seasonal Planetary Nebula
Clear skies I hope to you.