GAM 2017 Blog

By Megan Watzke

The Chandra X-ray Observatory is NASA’s premier X-ray telescope. In operation since its launch aboard the Space Shuttle Columbia in 1999, Chandra has studied hundreds of cosmic objects during thousands of observations over its 17-year mission thus far.

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As one of NASA’s Great Observatories (along with Hubble, Spitzer, and the now-deorbited Compton Gamma-ray Observatory), Chandra is a crown jewel of American astronomy.

However, Chandra is not just a national treasure, it is a resource for the entire world. Researchers from any country may apply for observing time on Chandra. In fact, scientists from over 100 countries have been awarded Chandra observing time during its lifetime.

How exactly is it decided who gets to use this X-ray facility that travels an elliptical orbit taking it a third of the way to the Moon? Observing time is determined by the proposal process. Anyone from any institution can propose to use Chandra, and each proposal is considered under the same rules.

Once all of the proposals are submitted annually (the Chandra deadline is usually in mid-March), they are separated into various topics – black holes, neutron stars, galaxies, etc. From there, a team of experts in that particular field evaluates the proposal to determine whether or not it represents a good use of Chandra time scientifically.  If a proposal is picked, then the person is notified and the observation is scheduled in the next year (called a “cycle” in NASA-speak). 


It takes a lot of work from many people – from the scientists who propose to the experts that review to the professionals who schedule – to bring an idea to use Chandra to fruition. However, all of this diligence pays off when researchers from around the world are able to make exciting and significant discoveries about the Universe we live in. To help celebrate Global Astronomy Month, please take a look at some of the latest amazing things that Chandra has helped us find:



meg profileMegan Watzke is the public affairs officer for the Chandra X-ray Observatory, a position she has held since 2000.  Her responsibilities include the dissemination of Chandra’s science results to the general public through press releases, press conferences, informal education and other activities.