Q&A: Chandra Mission

Q:
Why are the Chandra and the VLA telescopes different in size but have simliar resolutions? Are there any other telescopes that are a 100x better than both of them?

A:
Chandra is sensitive to x-ray wavelengths and the VLA is sensitive to radio wavelengths. These 2 types of radiation require very different methods for detecting them. Chandra needs long smooth mirrors made of iridium so that the high energy x-rays will not penetrate the mirrors, and instead will glance off and be focused onto the detectors at the base of the telescope. Radio radiation is detected in a much different way, using many large dishes spread over a large area. Radio waves are easier to detect for 2 reasons - radio waves are not absorbed by the Earth's atmosphere, so we can place radio telescopes in the ground instead of up in orbit like Chandra. And, radio radiation has much lower energy than x-rays, so it won't penetrate material like x-rays do. The technology for detecting each type of radiation is therefore very different.

There is no telescope, past or present, that has ever had a better angular resolution in x-rays than the Chandra telescope. The VLBI (Very Long Baseline Interferometry) might have a better resolution than the VLA but you'll have to look at their website to check this. Try going to Google (http://www.google.com) and searching on the keywords VLBI and VLA for answers.