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Chandra:
Space Travel:
Planets:
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Chandra: The Mission NASA launched a new telescope in to space in late July. It is called the Chandra X-ray Observatory and is worth $1.5 billion. Chandra produces high resolution (only 1/2 arcsecond) spectra. Chandra is a very big satellite. It is 13.8 meters long because of the nature of X-rays. X rays are made of high energy photons which need to bounce off mirrors and come in parallel to the surface. Chandra has a large orbit as well. The farthest distance from Earth is about 140,000 km. Chandra can be used to observe any target in the sky without having Earth block it's view. This will help it be more efficient than other satellites, spending 80 percent of it's time collecting information. The only problem with this far of a distance is that it can not be reached by shuttle, meaning we need to kepp faith taht there will be no problems for the next five years. The X-ray mirrors are mainly the reason why Chandra is so advanced. The mirrors have a high quality and can concentrate over half of the photons from a source in to a circle with a radius of 1/2 arcsecond. Making mirrors that are this good requires alot of work. They need to be polished until there is only a roughness of 10 angstroms. Also, the telescope's tiny beam gives sensitivity and resolution-angular and specral. Chandra will reslove "100 times more detail than we have ever seen before at X-ray wavelengths. This telescope gives us both images and spectra, two things which are needed to help understand the universe. Chandra's transmission gratings scatter the X-rays from objects in to a spectrum for each emission line. It has two cameras to photograph the images and spectra. One type of imager is the High Resolution Camera, which shows the widest field than any other tool on the spacecraft. NASA has created a Chandra Fellowship program. The first 11 Chandra Fellows will be able to study galaxies, clusters of galaxies. X-ray binary stars, black holes, and other phenomena. The most time will be spent studying ultrahot gas in clusters of galaxies. Chandra will also be used to find lovations of gamma-ray bursts. The first month in orbit will be a test to see if Chandra can work properly. It will open its instruments after this and try to locate targets. |