Telescope Definition and 517 Threads

Ok I'm working on my geometric optics homework and this is the last problem and I can't seem to get it right. An 6 astronomical telescope has a 32 cm focal-length objective lens. After looking at stars, an astronomer moves the eyepiece 1.0 cm farther away from the objective to focus on nearer...

Telescope spies 'youngest' planet An impression of what it might be like in the CoKu Tau 4 system Nasa's Spitzer telescope has found evidence around a distant star for a planet that may be less than one million years old. The infrared space observatory studied five stars in the...

I saw once a while back on the History Channel that Hubble looks something like 14.5 billion years into the past? I know very very very little about physics but this has me very interested. Could some one clarify this a bit? I assume that the reason Hubble looks into the past is because the...

Greetings All, I am attempting to develop a software simulation of the dynamics involved in machine figuring concave parabolic telescope mirrors. As a member of the amateur telescope making community, we currently don't have any tools to do this other than the "trial and error" method...

Is there any site that discuss about making telescopes that is fairly simple?

According to this article, some powerful folk are fighting O'Keefe's decision: http://skyandtelescope.com/news/article_1160_1.asp You might want to have your say too.

Some may be aware that 10 years ago or so, Texas Instruments began manufacturing a display device using nano-technology. It consists of a two dimensional array of mirrors. Each mirror can be actuated to lie at a different angle. It is strictly a binary device; a mirror is at one or the other...

If a telescope is 2 time bigger in diameter then you can see object 4 times fainter, but does that mean that object appear 4 times brighter?

Hi: I was looking for ideas for a homemade telescope for my son and saw this site, http://www.geocities.com/telescope1999/14-5inch.html Paging down some I saw that he made a telescope lens from the bottom of a bottle. It this possible? Did Bernard Schmidt really make such a...

While some comets are only visible with the help of a telescope, this comet, seen in 1965, was visible to the naked eye even during the day! What comet was it?

NASA have definitelly chosen the primary mirror for the JWST. It will be a berylium-based mirror. The JWST will be launched in 2011 to replace the Hubble www.universetoday.com/am/publish/james_webb_mirror_approved.html Woa! I can't wait til then!

Reading the article at http://www.msnbc.com/news/961142.asp?0dm=C13NT I saw that it said the new scope needed about a month to cool down to optimal operating temperature. Why would it take a month? E6S

This is not a homework question but I am posting it here because I think it may be too basic for the other forums. I am looking for a ray diagram for a reverse galilean telescope (ie. + eyepiece, - objective, so image is minified). Can anyone describe what the ray diagram would look like or...

I need tips on how to slow down a fast telescope. I've heard of showercaps, endcaps, and dustcovers; but what I need are details on how to construct a good quality piece that will stop down the aperture.

http://www.ehobbies.com/1004-2786.html I know a person who is selling this telescope for $300 used. He says it's in great shape. But I hear these telescopes are made cheap using cardboard and stuff. Anyone have experience or comments about them? I have a cheap-o 60mm refractor telescope...

well I am looking to buy a telescope... I want something with power.. I live somewhat near NYC (about 40 min) so I get a lot of city light in the sky... what do you guys think of this other than the fact that it weighs a lot.. its not something I would be lugging around.. only on rare...

I'm fixing to buy a telescope. I saw one in the Discovery Channel Store at the mall that has a digital camera. Are there any other sexy features on telescopes that I should know about? What are some good buys?