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amateur X-ray astronomy [try it]


You don’t always need a telescope to do astronomy in your backyard. Data from all the great space-borne observatories (like Hubble, Chandra, Spitzer, etc.) are publicly available for people to peer through and analyze on their own. All you need is a computer and a functional internet connection. The only things stopping people is that, first, they don’t know that these data are available, and second, they don’t know where to go to get the data, and third, they don’t know how to look at the data.

The Chandra X-ray Center has made available a data viewer called ds9 (named after the Star Trek series Deep Space Nine). It can be downloaded from, and instructions on how to use it are available at The CXC has also put up some tutorial-like examples on how to use it.

X-ray data are usually (though not always) stored as a list of detected photons. Each recorded photon is tagged with its time of arrival, a position on the detector, the an estimate of its energy. ds9 takes data files that are in this specialized format and displays them as images and lets you do various analyses like constructing light curves, extracting spectra, figuring out the intensity, etc.