Is human exploration beyond low Earth orbit a thing of the past? Will space tourism benefit and expand into low Earth orbit as space exploration beyond the Moon continues to be done through robotics?
These questions go to the heart of “The End of the Astronauts: Why Robots Are the Future of Exploration,” a thought-provoking new book co-authored by astrophysicists Donald Goldsmith and Martin Rees.
Although such arguments are not necessarily new, the authors highlight some new points that are worth repeating here.
—- Manned space travel is still dangerous.
High-energy solar and galactic particles abound throughout the solar system. Beyond Earth’s Van Allen radiation belts, astronauts are particularly vulnerable to radiation from such particles.
For every month in space, human bone density can decrease by up to 1.5 percent in weight-bearing areas of the body, such as the hips and knees. Astronauts spending six months en route to Mars would receive at least 60 percent of the recommended total radiation dose for a full career, the authors note. The trip back home would push them over the edge, even without a sudden increase in solar storms or flares, they point out.
—- Unlike human space exploration, non-human robotic explorers have safely and efficiently reached the outer edges of our solar system.
“Since its creation in 1958, NASA has spent about 60 percent more on human exploration than on robotic investigation of the cosmos,” the authors write. “We must keep in mind that human exploration of space has so far extended only to the Moon…”
—- Space-based telescopes do not need to be repaired by humans.
Although the Hubble Space Telescope would not have been operational without the ability to rescue it from what Goldsmith and Rees call “a fatal manufacturing defect,” they point out that the director of the Space Telescope Science Institute, which manages Hubble, “has said the The total cost of the five astronaut repair missions would have paid for the construction and launch of seven replacement telescopes.”
It is difficult to know if this would be the case, given the rising costs of instrumentation and space observatories in general. But the point is well taken. And perhaps that’s one of the reasons why Hubble’s follow-up observatory, NASA’s James Webb Space Telescope (JWST), was never designed to be staffed by human astronauts, at least.
From its current solar orbit, a million miles from Earth, the James Webb is currently out of range for a manned servicing mission. But so far it has proven to be well on track for full science operations due to begin this summer.
—- Artificial platforms for space colonies would hardly be Valhallas.
Artists often describe space colonies as exciting and inviting, akin to a resort, or some other realization of our hopes for a near-perfect environment, Goldsmith and Rees write. But the authors point out that this likely does not resemble the reality of such space colonies built in interplanetary space. They point out that there will be great difficulty and danger in maintaining such huge man-made structures in space, as well as the technical challenges involved in building them.
—- But space platforms would potentially allow billions of people to live in space.
As Goldsmith and Rees point out, “in his 1997 book “Mining the Sky,” cosmochemist John Lewis lamented that “as long as the human population remains as pitifully small as it is today, we will be severely limited in what we can do.” he emphasized that ‘human intelligence is the key to the future… Just having an Einstein, a da Vinci, a Bill Gates is not enough.’”
The implication is that maximizing our human potential might require increasing the human population a hundredfold. Space platforms would offer humans a sustainable way to increase our numbers and thus “roll the dice” for jinn to become more common. Who knows if such a scheme would work? Instead, it would be easier to artificially redesign our brains to make those once-in-a-lifetime geniuses more common than we could ever imagine.
This whole argument is a bit tangential to the book’s focus on why robots should prevail in space, at least for the time being.
Goldsmith and Rees make a compelling case for robotics over astronauts, at least in the short term. But hopefully 100 years from now, time and technology will allow us to have robust human interplanetary spaceflight and cutting-edge robotic space science and exploration.
In the short term, however, it probably makes sense to emphasize the exploration of the solar system through robotics, as national space agencies have brilliantly done for the past 65 years. It is truly amazing and how much has been achieved with so few dollars.
In time, hopefully there will be a meeting, that there will be a kind of fusion between the kind of robotics that can complement our human aspirations to travel to interstellar space in ways that are currently incomprehensible.