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:

  1.  “Trajectory Correction Maneuvers” or TCM’s for short.  Basically making changes to the orbit to precisely target the impact site.
  2. 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.
  3. 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!

10 thoughts on “Welcome”

  1. Thanks for the effort to keep those of us interested in this project informed, Paul!

    I am an amateur astronomer and hope to have clear weather (I live in the Pacific Northwest, near Seattle) to observe the impact through my 10″ home-made Dob telescope.

    I look forward to future updates.

    Thanks again,

  2. Dave wrote:
    “Where is the impact to take place, specifically what crater/region?”

    This is still being decided, based on the latest data from Kaguya and Chandrayaan-1. In fact, LRO data may be able to inform our science team’s selection of the crater. We have until Impact-30 days to make the final crater selection, beyond which point propellant costs are too high to change our minds.

    This said, it looks like the Cabaeus region of craters is our top choice so far. Interestingly, Shackleton, once a favorite, has recently been discovered to be much deeper and steeper-walled than theorized earlier. Too deep for LCROSS science, which relies on back-scattered sunlight on the ejecta cloud.

    Thanks for your question!


  3. My purpose in writing you is to see if you could answer a question concerning the possible visibility of a fuel dump from the Centaur stage the Atlas V rocket sometime after the LCROSS launch. As you are all probably aware, fuel dumps have occurred on other missions
    before and the end result has been to create an unusual and persistent
    luminescent cloud in the nighttime sky.

    Here is a great public relations opportunity (I think) to draw
    attention to the fact that we are once again making plans to return to the Moon. In addition to the coverage of the actual launch, an additional comment could be added to alert people to go outside and look for the fuel dump. From personal experience I can remember the thrill as a teenager of sighting the fuel dump of Apollo 14 as it headed toward the Moon some hours after its liftoff from Florida.

    In any case, if you have any advance details on this aspect of the
    upcoming mission, I would be most interested in hearing about them.

    With kindest regards
    — joe

  4. Joe Rao wrote:
    “My purpose in writing you is to see if you could answer a question concerning the possible visibility of a fuel dump from the Centaur stage the Atlas V rocket sometime after the LCROSS launch…”

    Joe, this is a great and captivating idea. I’m passing this on to our PAO staff. Our Navigation and Mission and Maneuver Design teams are pretty busy, but I’ll forward this to them as well. Perhaps we can get something together.

    Thank you for the great suggestion…


  5. Hi Paul

    First – as I’m writing this on first lunar insertion orbit day – CONGRATULATIONS !

    LRO is in lunar orbit !

    The banner that was outside Ames counting down .

    Can I get a copy of this – or even borrow better would be better still !

    I doing a large space display exhibition in UK in September 2009. This would be a good display item.

    Let me know how I could perhaps get hold of the banner for display.


  6. i would like to kmow how much debei will thrown up into space as aresult of impactand is there an enviromaetal impact done for the possibility of debre affecting Earth?

  7. has there been an enviromaetal impact study to measure the amount of debre that would thrown into space amd if there possibilty of some debri falling through the atmosphere


    We make microscopes to peek at tiny marvels
    and telescopes to scan enormties bit by bit,
    yet the human eye is strangely sightless
    when it comes to preventing manmade horrors.

    Indimidated by experts, we tap a cane ahead
    and step into nuclear wars, pollution, fearsome
    flirtations that risk the earth’s fragility.
    We leave it up to think tanks to persuade

    and governments to steal from sick,sad,needy
    people in order to endow NASA whose jet
    propulsions at this very moment have
    already rocketed to bomb the world’s moon.

    Without asking anyone’s okay, it will orbit
    till October 9, then explode in a crater, and 350
    tons of debris will rise. Lack of “a decent respect
    for the opinion of mankind” marks such ventures

    as curiosity gone wild — a “because it’s there”
    urge to exploit, to penetrate, that is truly
    vile and selfish. Yet to object seems foolhardy,
    so acceptable has aggression become.

    I feel a deep despair. My soul is ill-at-ease.
    Such an invasion, dressed up as science or truth,
    is actually a rape of the Mother of Evening, friend
    of wolves and lovers, keeper of time and tide.

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