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1 In the last several weeks, two events demanded the attention of space enthusiasts. On March 30, entrepreneur Elon
Musk's Space X company successfully reused a previously flown rocket to launch a communication satellite into space.
And on April 6, American space pioneer John Glenn was laid to rest.
2 In their own way. Musk and Glenn each represent the hopes and dreams of those who delight in the idea of mankind
leaving the bounds of Earth and exploring the solar system and, ultimately, the stars.
3 Over the past 50 years, we've seen men first orbit the globe and then walk on the moon. We were gripped by the
fictional journeys of the Starship Enterprise, which explored the galaxy, encountering new life and new civilizations.
Popcorn in hand, we watched Matt Damon struggle to survive in "The Martian."
O unfurled their
4 We have dreamed of a time when humans can travel through space as readily as when early mariners
sails and headed west in search of new lands. But we might not have stopped and asked an important question.
5 Should we be doing that?
6 Now, I am not asking whether we should explore the universe. I also dream of the day that we become galactic citizens.
The question is whether the initial exploration of space should be done by humans or by robots. I would argue that, for
the moment, robotic exploration should have the upper hand. Should humans, be
the ones exploring
Spoice?
7 Proponents of the astronaut-preferred camp point, quite rightfully, at the versatility and independence of humans. Fans
of human spaceflight are certainly correct when they remind us that humans are highly versatile, People observe the
conditions around them and can react to circumstances as needed.
8 However, people are also fragile. They need food, water, and air. They can exist in only a narrow range of temperatures
and find inhospitable both vacuums and a radioactive environment. While some adventurers might prefer to remain in
space forever, many of them expect to land gently back on Earth. All of these considerations are extremely challenging
and not important for robotic missions.
9 Engineering spacecraft that satisfies human requirements is also very expensive. The International Space Station cost
about $170 billion (all costs given in 2017 dollars), resulting only in a large facility locked in a low earth orbit. The storied
Apollo missions included a mere six lunar landings, at an inflation-adjusted cost of $120 billion.
10 Possible manned missions to Mars are imagined to cost about $1 trillion, with the outcome being limited exploration of
the Red Planet by about 2030 (with some estimates saying 2050). And a mission with that price tag would hamstring
the rest of the space program.
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11 In contrast, robotic exploration of the solar system is far less costly. The Cassini mission to Saturn cost about $3.2
billion. The Mars Curiosity Rover cost about $2.5 billion. These and other missions have been wildly successful in
How expensive
the missions have
been.
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