Friday, November 12, 2010
James Watson and Francis Crick stopped by the Eagle after leaving the
Cavendish Lab on Saturday, February 28, 1953. Crick raised his glass and
announced to all in the pub, "we have discovered the secret of life." And
they had; they had unraveled the structure of DNA, the secret of life on
our planet. We share genes with every creature that crawls on Earth. But
could nature have found other ways on other worlds to solve the problem of
life? That would be an even greater discovery. We have seen no hint of
life on the other planets in our solar system, though we havent yet poked
into every corner. In any case, the search for life to which we are not
related now reaches beyond the solar system to our region of the Milky Way
galaxy. The Third Millennium began with the discovery of planets
orbiting
stars other than our Sun. We should be able to study these exoplanets
with
the world's greatest telescope, under development at NASA Goddard. Its
100 times more powerful than the Hubble, but trouble looms.
The James Webb Space Telescope is in trouble. Barbara Mikulski (D-MD), who
chairs the appropriations subcommitte that oversees NASA, clearly saw
trouble back in June when she requested a review of the NASA budget. The
review came in this week. The bottom line is that the James Webb space
telescope is a year behind schedule and $200 million short. Christopher
Scolese, associate administrator of NASA, agreed with the report's
findings, but could not see where they could find the money. I should
tell
him the secret, NASA is bifurcated. The NASA thats the envy of the world,
we might call "Exploration NASA," its a science agency that discovers
exoplanets and puts rovers on Mars. Then theres "Carnival NASA." It
arranges trips to space for people with too much disposable income, and
looks for water on the Moon to make rocket fuel.
There are two obvious places to locate space observatories. They were
identified by the great French-Italian mathematician Joseph Lagrange 237
years ago, long before anyone even imagined space observatories. The
Lagrange points mark positions where the combined gravitational pull of
the
two large masses (Earth and Sun) provides precisely the centripetal force
required to rotate a relatively small mass (the observatory) with them.
There are five Lagrange points in the Earth-Sun system. The first two are
the important ones. L-1 is about 1.5 million km from Earth on a line to
the Sun. It is the perfect position from which to monitor the Sun in one
direction, and the full illuminated Earth in the other. It is thus ideally
situated to monitor changes in Earth's albedo. Americans paid more than
$100 million for an observatory at L-1, now called dscovr, the deep space
climate observatory. For unexplained reasons it is sitting idle in a
warehouse in Greenbelt, MD. The L-2 point is 1.5 million km from Earth on
a
line directly away from the Sun. It is patiently waiting for the James
Webb space telescope.
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