The Official Astronomy Thread

[LazyLion]

http://kisd.de/~krystian/starmap/

 

[Crusader]

http://kisd.de/~krystian/starmap/

That is SO cool! Gives an excellent idea of how the stars are located. Way better than any 2D map.

 

[Gaz{M}]

Can you actually see the "horse head" part of the horsehead nebula with an 8" or 10" scope? What magnification?

 

[Crusader]

I'll have to check no this, but it should be visible in a 10" provided you have a H-Alpha filter to make the wavelength me the light visible. Without the right filter it will be impossible (or as close to) to see it.

 

[mercurial]

I'll have to check no this, but it should be visible in a 10" provided you have a H-Alpha filter to make the wavelength me the light visible. Without the right filter it will be impossible (or as close to) to see it.

Correct.

 

[Crusader]

Just checked and it seems some people have reported seeing it in a 10" without using a filter but with excellent viewing conditions and then only as an averted vision object. So it's exceptionally faint and you'll have to have trained yourself to see faint nebulae to be able to see it without a filter and then it will be very faint.

 

[Gaz{M}]

Great, thanks for the replies. I've done some reading and it seems that the horsehead doesn't emit much light in the visible spectrum, so a filter is needed. I've seen some stunning long exposures giving a bright red cloud even from a modest telescope though. I think the horsehead is probably one of the most fascinating objects in the sky.

Another question - I'm trying to see why the Eagle nebula is so named - I'm struggling to see the "eagle" shape I assume gave it the name?

 

[mercurial]

Great, thanks for the replies. I've done some reading and it seems that the horsehead doesn't emit much light in the visible spectrum, so a filter is needed. I've seen some stunning long exposures giving a bright red cloud even from a modest telescope though. I think the horsehead is probably one of the most fascinating objects in the sky.

Another question - I'm trying to see why the Eagle nebula is so named - I'm struggling to see the "eagle" shape I assume gave it the name?

It is the most stunning IMO too. I don't know why it's called Eagle either.

 

[Gaz{M}]

The nebula resembles an eagle with outstretched wings and talons ready to strike. I've made the image below to illustrate:

 

[Crusader]

Good explanatory image. With my O-III filter I can definitely make out the "outstretched wings" shape, although many me the common names for the objects take loads me imagination to see the resemblance.

 

[mercurial]

For some reason, I'm not seeing any images here. Guess I'll have to go into the quote and manually type in the URL.

 

[mercurial]

That looks like a freakin' dinosaur. They should have called it the dinosaur nebula.

 

[Kalvaer]

BTW... do you all know next year is the year of Astronomy... SALT is opening up its grounds for old years eve for the first time ever for the event.. will post more details later if anyone wants

 

[Crusader]

BTW... do you all know next year is the year of Astronomy...

Yup, well aware of the fact. I've even downloaded the official theme song for IYA, "Shoulders of Giants" and must say that it rocks - at least it should for any astro geeks. Be aware though that it will definitely induce scope withdrawal if you have cloudy weather!

 

[mercurial]

Anyone have a laser collimator?

 

[Crusader]

Yup, I've got the lasermate deluxe that came with my XT10.

 

[mercurial]

Yup, I've got the lasermate deluxe that came with my XT10.

Cool. How well does it work and how often do you have to collimate? Also, I want to clean my mirror. Kalvaer gave me some links but they all involve too many processes, and I'm very lazy
Are there any quick ways to clean them?

 

[Kalvaer]

I collimate everytime I take my scope out just to be sure. After a while you can do it under 5 min so it becomes part of the whole setup procedure while I'm waiting for my scope to cool down.

Here is a very nice detailed explaination using a barlow for very fine tuning: http://www.cameraconcepts.com/barlowed laser collimation.pdf

As to the mirrors.. unfortunately there is now safe quick way. You can try "blow" it clean but you still need to be careful

 

[mercurial]

I collimate everytime I take my scope out just to be sure. After a while you can do it under 5 min so it becomes part of the whole setup procedure while I'm waiting for my scope to cool down.

Here is a very nice detailed explaination using a barlow for very fine tuning: http://www.cameraconcepts.com/barlowed laser collimation.pdf

As to the mirrors.. unfortunately there is now safe quick way. You can try "blow" it clean but you still need to be careful

Cool, thanks!

 

[Crusader]

I also use the barlowed laser method, much easier and you don't have to worry about the collimation of the laser (which after testing after the barlowed method, seems to be way off - you can even see it by just rotating the lasermate in the focuser).

As for cleaning the mirror, unless it is extremely dirty I'd just leave it alone. Some dust on the mirror won't affect your view.