Friday, July 8, 2011
In the beginning US space priorities were set by the Soviet Union. 0ur
only priority was to win. We won hands down, but the end of the Cold War
left us split. With the memory of tickertape parades in the Apollo program
still fresh, one side wanted to go Hollywood with the focus on heroic
astronauts. The other side thought NASA should be a science agency,
leading the way into a new age of scientific instrumentation. The game
ended in a tie. NASA was split right down the middle: manned and
unmanned. By any objective measure the manned program is an expensive
drag, but it was never meant to be judged objectively. The end of the
shuttle program gives us a tiny window of opportunity to rethink the space
option. The highest priority must be to protect Earth by: 1) identifying
all Earth-crossing asteroids and projecting their trajectories into the
distant future, and 2) locating the DSCOVR observatory at the L-1 point to
monitor solar activity and climate change on the whole Earth. This is the
most urgent responsibility imaginable and only the US can do it.
Saturday, a major review by a committee of experts from Britain, the United
States and Sweden concluded there is no convincing evidence connecting cell
phone use to cancer, and no established biological mechanism by which
microwaves might trigger cancer. Their conclusion is, of course, correct.
So why am I troubled? Some of you must recall the virulently anti-science
postmodern movement. About 15 years ago it was argued that there is no
such thing as objective truth: Science is a product of the power structure
it serves, and scientific "laws" would come out differently in a different
culture. It pictured scientists sitting around a table voting on the
truth. Does that seem uncomfortably close to where we are on cell
phone /cancer issue?
In a special issue a couple of months ago Nature reported that there have
been five mass extinctions over the past 540 million years in which the
number of species declined by over 75% in a geologically brief interval,
http://bobpark.physics.umd.edu/WN11/wn030411.html.
If you're not already depressed, keep reading; you will be. An expert panel of scientists,
convened by the International Program on the State of the Ocean (IPSO),
released its report a couple weeks ago. It warns that ocean life is at
high risk of entering a phase of extinction of marine species unprecedented
in human history. There is a growing conviction that life on Earth has
already entered mass-extinction six. Previous extinction episodes have
presumably been initiated by catastrophic natural events, such as increased
volcanism, changes in sea level, or asteroid impacts. Mass-extinction-six,
however, is decidedly unnatural, resulting entirely from the spread of
civilization.
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