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Find the Diameter of HT Cas!

You are progressing nicely in your astrophysics studies, but you are looking for advancement. You want to work with Dr. Greenglow, a famous cosmologist at your University, but competition is stiff. She has only two positions in her lab this semester, and to qualify for one of them, you must be the first one to find the answer to the current challenge question, using real science methods. You aren't allowed to look the answer up, in a book or on the Web, or ask another scientist at the lab. You can use all of NASA's resources (many are available on the Web), as well as your stunning intellect.

The challenge question, which is posted on Dr. Greenglow's office door, is: What is the diameter of the central star in the X-ray binary system HT Cas? To answer this challenge question, do you want to:

Info Read up on HT Cas.

Experiment Make optical observations of the central star in HT Cas.

Experiment Send two probes to HT Cas that will send back radar signals to Earth.

Experiment Observe X-ray emission from the system and use the fact that HT Cas is an eclipsing binary.

Imagine the Universe is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center.

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All material on this site has been created and updated between 1997-2012.

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