X-ray Telescope: why is it Different?

Most recent answer: 10/22/2007

Q:
how dose a x ray telescope work?
- joseph
cleveland,OH USA
A:
In any telescope you need two things; something to focus the light to an image and, a mechanism that records the resulting image.  In an ordinary optical telescope the focussing  can either be done by a properly shaped piece of glass (a lens) or by a parabolic mirror.  The recording mechanism can be your eye, a sheet of photographic film or, like in modern digital cameras, an array of CCD (charge coupled device) pixels.

In an x-ray telescope both the lens and the the image detector present  problems.  Neither glass nor ordinary mirrors work because the x-rays go right through them.  The answer is to use what is called a ’grazing incidence mirror’. The image detector is called a ’micro-channel plate’.  

There is a nice description of the famous Chandra_X-ray telescope at:


LeeH


(published on 10/22/2007)