GRAIL: Another Lofty Quest (Part 2) September 6, 2011Posted by Lofty Ambitions in Science, Space Exploration.
Tags: GRAIL: Another Lofty Quest, GRAILTweetup, Physics
Today, Doug is traveling to the Space Coast, making that cross-country SNA–MCO trip yet once again, though he’s going it alone this time. Doug will be en route for about nine hours, and Anna is booked solid with student conferences and teaching for nine hours, though these nine-hour stretches overlap so that we’ll probably be out of touch with each other for at least twelve hours. We outlined the week’s posts on Saturday and drafted this one on Sunday. Working together this week started by working ahead. How collaboration will happen tomorrow, we’re not quite sure.
Meanwhile, what’s this trip all about? Why are we willing to cross the bridge yet another time on this quest for GRAIL?
GRAIL is the Gravity Recovery and Interior Laboratory, which is scheduled to be launched from pad 17B at Cape Canaveral Air Force Station during one of two one-second launch windows on Thursday (or sometime by October 19). GRAIL is actually two spacecraft, nearly identical twins that will travel toward the Moon for a few months, then begin orbiting. For a couple of months the two spacecraft will adjust their orbits until one is following the other in a low-altitude, near-circular path of formation flying.
Each washing-machine-sized craft contains a Gravity Ranging System that, according to NASA, keeps track of the distance between the two craft down to the diameter of a red blood cell. The laboratory aboard each craft is designed to map the Moon so that we can better understand the Moon’s history. GRAIL’s goal is to answer scientific questions about the Moon interior and thermal characteristics.
Each craft also contains MoonKAM (Moon Knowledge Acquired by Middle-school students as part of Sally Ride Science) cameras because part of the GRAIL mission is to take photos for educational and public outreach purposes. The mission is part science and part fun—uh, we mean educational.
NASA’s compares GRAIL to the five-year GRACE project, which launched in 2002 and mapped the Earth. By using geodetic-quality Global Positioning System technology, accurate measurements between the two GRACE spacecraft have produced measurements and images of the Earth’s gravity fields. We can now see variations and changes within land masses, interactions between land masses and bodies of water, and characteristics of the atmosphere. We think of the globe as uniformly spherical, but GRACE reveals that we live on a lumpy planet.
GRAIL is almost ready to go take a look at the Moon and determine its lumps, bumps, and past. On August 18, the spacecraft were moved from Astrotech in Titusville to the launch pad and encapsulated for the journey on August 23. The Delta II rocket is ready to roar. This morning review meeting gave a Go! for launch (click HERE for that press release).
So Doug and the rest of the space tweeple are making their ways to the Space Coast in hopes that GRAIL launches on Thursday (or maybe Friday). Among those invited to the Tweetup is Justine McKinnon, the sole Brit and a mother of four. Several of the participants are also bloggers, some have affiliations with Kennedy Space Center or the Jet Propulsion Laboratory that built GRAIL, and one is a pastor. Others are teachers or students. Eight hundred people vied for 150 spots. Seven countries and 32 states are represented.
The Tweetup schedule looks pretty amazing, including events with NASA Administrator Charlie Bolden, astrophysicist Neil deGrasse Tyson, and GRAIL scientists. We’re interested to compare the experiences in social media coverage with those of news media coverage. In this world of almost instantaneous sharing of information, what exactly is the difference between news coverage and 150 tweeps relaying 140-character tidbits? Who among us asks questions, and whose answers do we heed? Who now makes the distinction between an African and European swallow when asked about a swallow’s airspeed?