NASA Blog: Welcome to the GLAST Project Scientist Blog!

There are many people around the world interested in the progress of the GLAST mission, and we will post status updates here. Please check back often. I plan to include frequent “guest” postings from some of the many scientists, engineers, and others from around the world who make GLAST possible. First, what is GLAST?

GLAST is the Gamma-ray Large Area Space Telescope. NASA’s GLAST mission is an astrophysics and particle physics partnership, developed in collaboration with the U.S. Department of Energy, along with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden, and the U.S. Please have a look at our mission website, and links therein, for information about the mission and a great media gallery. There aren’t many times in a scientific career when such a large leap in capabilities is made in a single step, and we’re very excited about what GLAST will soon reveal to us about the Universe. What is GLAST doing now?

Since the dramatic and very successful launch on 11 June at 12:05 PM EDT to a circular orbit 565 km above the Earth, the GLAST team at the Mission Operations Center has been working around the clock to check out all the functions of the spacecraft. About two weeks after launch, we will turn on the two beautiful GLAST instruments: the Large Area Telescope (LAT) and GLAST Burst Monitor (GBM). More about these activities and the instruments in future posts.

Things are going very well thus far, and there is much more to do (we have not opened the champagne yet!). Here is a quick recap of the activities since the launch:

• Thursday 12 June. Routine communications are established, and the observatory is operating in a very stable manner. All spacecraft navigational systems are powered on, and solar array drive checked out.
• Friday 13 June. The star tracker system (small telescopes on the side of the spacecraft that help determine the orientation of the observatory by automatically recognizing patterns of bright stars) is initialized and functioning well, after some very efficient and clever detective work by the mission team to solve an initial configuration mismatch.
• Saturday 14 June. The observatory transitions from a pointed observing mode (staring in one direction all the time) to survey mode (sweeping the boresight of the instruments across the sky) — a beautiful ballet maneuver! To accomplish this, many things must work together in a coordinated way, and this is a great milestone in the early operations checkout.
• Sunday 15 June – Monday 16 June. Maneuvering exercises and calibrations. GLAST changes its orientation (aka “slews”) by changing the rotation speeds of four onboard wheels, called reaction wheels. The onboard computer coordinates these speed changes with the orientation of the solar arrays, all the time monitoring the position on the sky using GPS (the Global Position System, which GLAST uses for both position and time information), the star trackers, and special gyroscopes.

What’s next for GLAST?

Slew maneuver exercises will continue until Wednesday, when GLAST’s main science data antenna will be turned on and checked out.

Peeking further ahead, you can find an overview of the first year science timeline here. We’re really looking forward to this!