Our Non-Expeditions
to the Moon and Mars
Look closely: President Bush's space initiative
is more about robots than astronauts
Richard A. Muller
February 19, 2004
Many people
think that in his January 14 speech on the space program, President George Bush
announced a new initiative to return humans to the moon and soon afterwards
send them to Mars. He didn't. What he announced was a cancellation of the space
shuttle and a reduction of the United States' long-term commitment to the
International Space Station. For the immediate future, he proposed an expanded
program of unmanned exploration of space, with an emphasis on the planets and
the solar system. I know--that's not what most people read in the headlines of
their papers. So let's look at President
Bush's speech
closely, with particular attention to the dates when missions will fly.
The president
used much of his speech to describe the great accomplishments of the space
program. These included practical applications--unmanned satellites used to
predict weather, to communicate, and to determine location (the Global
Positioning System). But his real emphasis was on NASA's scientific
achievements, including our growing exploration of the universe. He mentioned
the Apollo missions to the moon only in passing. He talked of images taken by
telescopes, and knowledge sent back by 'robotic explorers' including Spirit,
the Martian rover. His emphasis on unmanned projects was surprising and
significant. And he was right; the unmanned program is NASA's most glorious
achievement over the last three decades. Moreover, it is this aspect of space
exploration that most excites the public. The Astronomy
Picture of the Day
fascinates schoolchildren and adults alike, many of whom download the images
for screen savers. In contrast, stories of astronauts floating for months in
the space station are considered so boring they don't even make the back pages
of newspapers, let alone the evening news.
Just as
important in President Bush's speech were his omissions. He made no mention of
industry in space--of the possibility of rounder ball bearings or purer
semiconductors. He made no reference to space travel so cheap that it becomes
commonplace. Those ancient and hopeless goals, used in the original
justification of the shuttle program, were abandoned, and for that I am
thankful. They were never realistic, never made economic sense, and they
interfered with legitimate science and exploration programs.
The greatest
achievements in President Bush's list did not relate in any compelling way to
humans in space. Yes, the Hubble Space Telescope was launched and serviced by
the shuttle, but most scientists believe that the telescope program would have
accomplished even more per dollar spent if it had been designed and
executed separately from the manned space program. Repairing and extending the
life of this system using the shuttle is arguably more expensive than sending a
new satellite aloft, particularly since the Hubble telescope had to be made
safe for astronauts to be near. The military has launched spy telescopes for
decades without need for human servicing. How big were they? Basic optics tells
us that a telescope's resolution depends on the diameter of its mirror. Do the
simple math and you'll find that the ability read a license plate from an
altitude of 500 kilometers requires a mirror 3 meters across; the Hubble's
mirror is 2.4 meters.
President Bush
announced that the shuttle will continue until 2010--but that's only six more
years of operation. He is ending the shuttle program. In its remaining life,
the shuttle's main goal will be to 'complete' the International Space Station,
to 'finish what we have started.'
Will anyone take
that to be an enthusiastic endorsement of the space station? How will our 15
international collaborators interpret his word 'finish'? The only value
of the space station that President Bush cited was study of the biology of
human endurance in a weightless environment. He mentioned no other scientific
purpose, and rightly so. Most scientists launching space experiments prefer a
satellite isolated from human pollution and noise, and unencumbered
by the added expense of making it safe for humans to work around.
The replacement
for the shuttle, the 'Crew Exploration Vehicle,' will be operational 'no later
than 2014,' the president said. There may be four years, 2010 to 2014, when the
U.S. can't fly to the space station. Is that a golden opportunity for Russia to
take over the business of shuttling people and cargo to the station? Or is it a
signal that it is time for our 15 collaborators to cut their losses, too? I'm
guessing that by the time the Crew Exploration Vehicle is ready to go there,
the space station will have long since been abandoned.
Before the
Columbia tragedy, the Hubble Space Telescope had been scheduled for a repair
and upgrade visit in 2005. Now, however, NASA is asking whether such a mission
is worth the risk to astronauts. Instead, NASA is considering spending $300
million to develop a robotic tug that will attach itself to the telescope and
crash it into the ocean, to make sure the instrument's return to earth does no
harm to humans. The thought of destroying Hubble has triggered much sound and fury
among scientists. There is great irony here, for the dispute illustrates NASA's
success in addicting scientists to a vehicle that they never wanted. It is not
the Mars mission that threatens Hubble--it is the cancellation of the shuttle,
something that should be done regardless of Mars.
Here are some
key points. First, $300 million to deorbit Hubble safely would represent the
most money ever spent per life saved in the history of mankind, by far. A mere
million dollars spent on improving ambulance service in the United States would
save many more lives; even better would be sending medicine to impoverished
regions of the world. Second, Hubble was designed to be human-serviceable not
to save money, but to provide a scientific excuse for the shuttle. It is
arguably cheaper to start building next-generation astronaut-free systems than
to continue servicing the present telescope. Third, a trip to Hubble is
more dangerous than a trip to the space station, because it offers no chance to
repair tiles damaged on launch.
Either mission
risks the lives of astronauts, and the decision will not be easy. But if
the decision is between a dangerous trip to the space station, with no
scientific return, and a more dangerous trip to Hubble, with enormous return, I
think the United States will decide for Hubble. My reading of President Bush's
speech is that the only achievement worth risking human life for is knowledge
and exploration--and for that, you can't beat Hubble.
President Bush's
speech has been widely characterized as a plan to send astronauts to the moon
and Mars. But the goal for reaching the moon is 2020, and for Mars it is 2030.
This isn't a plan, or a program--it's more like a long-term dream.
Let's look at what
will actually happen
by the end of this decade under President Bush's plan. The shuttle will be
cancelled, and the space station will be abandoned. Only one of the goals
announced by Bush could take place within his presidency. Back to his speech:
'Beginning no later than 2008, we will send a series of robotic missions to the
lunar surface to research and prepare for future human exploration. Robotic
missions will serve as trailblazers, the advanced guard to the unknown. Probes,
landers, and other vehicles of this kind continue to prove their worth, sending
spectacular images and vast amounts of data back to Earth.'
President Bush
is right. The space shuttle and the space station deserve termination. The true
heart of his proposal is the elimination of these programs, and the
substitution of robotic exploration. We will look before we leap--that is, fly
telescopes built for visible, infrared, ultraviolet, microwave, x-ray, and
gamma ray wavelengths--to see what we can see from Earth orbit. Then we will send
robots to explore whatever robots can explore. Hold back on the astronauts
until we have goals that need them. Let science be the guide, rather than a
presumed human need to step off the surface of the Earth.
Some people will
say I am too optimistic, that I am reading too much in between the lines. I
think I am just ignoring the headlines to read the actual lines themselves.
President Bush gave us a great plan. Let's recognize that and go with it. But
let's be careful to make sure that politicians and bureaucrats do not hijack
President Bush's wonderful vision of robotic space exploration and degrade it
into a listless program that merely launches astronauts to places where
telescopes and probes could do a safer, quicker, better, and cheaper job.
Richard A. Muller, a 1982 MacArthur Fellow, is a physics professor at the University of California, Berkeley, where he teaches a course called 'Physics for Future Presidents.' Since 1972, he has been a Jason consultant on U.S. national security.