hector
02-11-2008, 08:31 PM
I was wondering if anyone would be interested in a regular thread for a series of challenging objects for a variety of size scopes every month.
to start
Binoculars
Nebula in another galaxy: 10x50 Bino's will show the Nebula NGC346 in the SMC. Look for a small glow just a little North East of the centre of the galaxy. Once you have seen it remember that you are looking at a Stellar nursery about 200,000 light years distant.
4-6" Scope
This observation is really for a rich field instrument f5-6. The Sculptor Dwarf is a satalite galaxy of the Milky Way. It is a Dwarf Spheroidal with a very low surface brightness. Select a low power wide field eyepiece and position the galaxy in the middle of the field. If you can see a brightening in the sky background you have found the galaxy. if your not sure give the scope a shake if the glow mooves you have it.
8-10" scope
NGC6288 is a galaxy in Sagittarius and another satalite of the Milky Way. It is an Irregular galaxy which contains numerous HII regions. It was the first galaxy to have the Variable stars correctly maesured and as such was the first known extragalatic object. In the 8-10" scope it wlill appear as a low surface brightness bar about 16' long and 6' wide. If you have a UHC filter handy have a look again and see if you can see the HII regions on the Northern end of the galaxy.
12-14" scope
WLM is another local group galaxy. It lies about 2.5 million LY away. This is a difficult galaxy to observe looking very similar to NGC6288 only smaller and fainter. Where NGC6288 has a gradual drop in surface brightness WLM has quite a sharp drop, making it easy to distinguish from the sky background.
It is 7' long by 4 ' wide and has a fairly bright star superimposed in the centre of the galaxy.
16-18" scope
WLM is good for this size scope as you should be able to catch an extragalatic globular. See the image attached to this message and you will see thew cluster marked. This is one of the easiest Extragalctic globulars.
20" and bigger.
You thought I would go for another Local group member and you are correct. This will be another challenge and it comes in 3 parts.
First part the Fornax Dwarf. not a particularly hard challenge for the size instrument requested. Second the 5 globulars again marked on the image posted with the message. Last is the Cluster marked as C and this is the real challenge. The only open cluster in the Fornax galaxy.
Anyone with a large instrument can try all objects and I urge anyone with a smaller scope to try and look at the objects listed for larger instruments. you never know.
I hope that people like this and if you do I will try and have one ready for each month. Till December......
Andrew
to start
Binoculars
Nebula in another galaxy: 10x50 Bino's will show the Nebula NGC346 in the SMC. Look for a small glow just a little North East of the centre of the galaxy. Once you have seen it remember that you are looking at a Stellar nursery about 200,000 light years distant.
4-6" Scope
This observation is really for a rich field instrument f5-6. The Sculptor Dwarf is a satalite galaxy of the Milky Way. It is a Dwarf Spheroidal with a very low surface brightness. Select a low power wide field eyepiece and position the galaxy in the middle of the field. If you can see a brightening in the sky background you have found the galaxy. if your not sure give the scope a shake if the glow mooves you have it.
8-10" scope
NGC6288 is a galaxy in Sagittarius and another satalite of the Milky Way. It is an Irregular galaxy which contains numerous HII regions. It was the first galaxy to have the Variable stars correctly maesured and as such was the first known extragalatic object. In the 8-10" scope it wlill appear as a low surface brightness bar about 16' long and 6' wide. If you have a UHC filter handy have a look again and see if you can see the HII regions on the Northern end of the galaxy.
12-14" scope
WLM is another local group galaxy. It lies about 2.5 million LY away. This is a difficult galaxy to observe looking very similar to NGC6288 only smaller and fainter. Where NGC6288 has a gradual drop in surface brightness WLM has quite a sharp drop, making it easy to distinguish from the sky background.
It is 7' long by 4 ' wide and has a fairly bright star superimposed in the centre of the galaxy.
16-18" scope
WLM is good for this size scope as you should be able to catch an extragalatic globular. See the image attached to this message and you will see thew cluster marked. This is one of the easiest Extragalctic globulars.
20" and bigger.
You thought I would go for another Local group member and you are correct. This will be another challenge and it comes in 3 parts.
First part the Fornax Dwarf. not a particularly hard challenge for the size instrument requested. Second the 5 globulars again marked on the image posted with the message. Last is the Cluster marked as C and this is the real challenge. The only open cluster in the Fornax galaxy.
Anyone with a large instrument can try all objects and I urge anyone with a smaller scope to try and look at the objects listed for larger instruments. you never know.
I hope that people like this and if you do I will try and have one ready for each month. Till December......
Andrew