Welcome everyone to the first installment of the LCROSS Flight Blog! LCROSS stands for Lunar Crater and Observation and Sensing Satellite. It is one of two spacecraft launching to the moon in June of 2009, as part of a coordinated effort to explore the moon in unprecedented detail, in preparation for human missions in the not-so-distant future. If you’re not familiar with the mission concept, I’d suggest you start with our project website:
What you may not know is that LCROSS does not fly all by itself. During our mission, a team, called the Mission Operations Team (or Flight Team for short), will remotely operate the spacecraft from NASA Ames Research Center in the Bay Area in California, as well as from other operations facilities around the country and around the world.
My name is Paul Tompkins, and I’m the Flight Team Leader and one of the Flight Directors for the LCROSS mission. In this blog, I’ll do my best to describe what it’s like to be a part of this team. I’ll be posting as often as possible as the LCROSS launch date approaches, and during the mission to provide play-by-play updates of the mission. Above all, I hope I can convey the excitement all of us on the team are all feeling, and to get you excited about the moon!
So, what does the Flight Team do? Well, most spacecraft can’t do a whole lot without human input. LCROSS is a simple robotic spacecraft – there’s no one on board, it can’t do too much thinking on its own, and so we control it from the ground. After launch, the Flight Team gets to “take the keys” to “fly” the spacecraft to complete its mission.
The specifics aren’t quite so romantic, but are still pretty interesting (hopefully you’ll agree!). The Flight Team has a “mission plan” that describes what activities need to happen at different times in the mission, so that we can accurately target our impact location on the moon, and be ready to observe the impact to find water. In broad terms, the main activities are:
- “Trajectory Correction Maneuvers” or TCM’s for short. Basically making changes to the orbit to precisely target the impact site.
- Science Payload Calibrations: The set of instruments LCROSS has onboard to detect water, along with a special computer that is dedicated to instrument control, is collectively known as the “Payload”. All high-precision instruments need to be calibrated so that a scientist knows how a particular measurement relates to known, physical quantities. By the time of impact, our instruments need to be well calibrated.
- Other Supporting Engineering Activities: There are a lot of other things we command the spacecraft to do to support the other activities. Things like changing the orientation of the spacecraft to point instruments or antennas in a specific direction, calibrating our onboard clock, changing the rate at which we return data to Earth, etc.
The Flight Team gets information from the spacecraft, called telemetry, that tells us whether the spacecraft is healthy or not – things like temperatures at different locations, the pressure in the propellant tank, the battery voltage, electrical currents flowing to each unit in the system.
According to the mission plan and based on what we read in telemetry, we design specific sequences of commands to perform the activities listed earlier. Then we actually sit in a control room and send the commands to the spacecraft, and monitor how it behaves. If it does what we expect, then everything is OK. If it malfunctions, then our team can detect that and make corrections, and keep the spacecraft safe. Think of the movie “Apollo 13”. Except MUCH smaller scale, with no astronauts onboard the spacecraft, no pocket protectors, cigars or jazzy vests. Our team is pretty small, and doesn’t have quite the responsibility of a team overseeing human spaceflight operations. Still, lots of responsibility!
Well, that’s it for today. Thanks for reading, and I’ll post again soon!