Friday, March 16, 2007
In 1998 Congress mandated a NASA Spaceguard Survey to discover,
track and catalog the 20,000 or so near-earth asteroids and
comets. NASA is behind schedule. Asteroids usually show up
around budget time. The latest is named Apophis, which is headed
our way in 2036. WN has a call in to Bruce Willis to see if he
will be available in 2036. Apophis is nothing like the asteroid
that spelled curtains for the dinosaurs 65 million years ago, nor
does it have much chance of hitting Earth, but you play the cards
you're dealt. This morning's New York Times has an op-ed by
Apollo astronaut Russell Schweickart calling for public hearings
to "shame" NASA into action. This looks like the old "Washington
Monument ploy," in which the Park Service threatens to close the
most popular visitor site because of budget problems.
Yesterday, Bart Gordon (D-TN), chair of the House S&T Committee,
noted that the budget reality bears little resemblance to the
"rosy projections" offered by the Administration when the
President announced his "Vision for Space Exploration" three
years ago. Don't scrap the vision - kill the science. One
casualty is the $1.5 billion Alpha Magnetic Spectrometer that was
scheduled to go to the ISS on a 2008 shuttle flight. Griffin now
says there's no room for the AMS on the shuttle because every
flight is crammed with hardware to finish the ISS. It wouldn't
do to drop an unfinished ISS into the ocean. The AMS was
designed to search for antimatter. Nobel prize winner Sam Ting
of MIT, made the case for AMS personally to Dan Goldin. It was
cited repeatedly by NASA to show that the ISS would do basic
science (WN 12 Jun 98) .
An instrument called the Mars Advanced Radar for Subsurface and
Ionospheric Sounding (MARSIS) on board the Mars Express has
measured the water trapped in layers covering the south polar
region. The icy layers cover an area bigger than Texas, and in
places as deep as 3.7 km. That is enough water to cover the
entire planet with a layer 11 meters deep. They are now mapping
the layers around the north pole of the arid planet.
And they don't know why. In Greenland the loss of ice is caused
by melting, but that doesn't explain the rapid movement of ice
into the ocean from the frigid West Antarctic ice sheet, even as
the East Antarctic ice sheet is growing. The net loss is huge,
raising sea levels. A special issue on Polar Science in today's
Science magazine, notes that good measurements of the thickness
of the ice sheet have only been made in the past ten years, so it
is not yet possible to tell if this is a natural cycle.
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