The conventional wisdom of space exploration suggests that robotic probes are both more scientifically efficient and cost effective. Not so, argues a professor of planetary science.
Astronaut Edwin E. Aldrin Jr., lunar module pilot, poses beside the deployed flag of the United States during the Apollo XI moon landing July 20, 1969. [Reuters]
When the Space Shuttle Atlantis rolled to a stop in July 2011, NASA bid farewell to the nation's symbol of manned spaceflight. The Obama administration has scrapped NASA's plan to return humans to the Moon by 2020, which was behind schedule because of technical and budgetary problems. As financial constraints threaten the possibility of future ventures into outer space, many in the astronomical community are advocating for the increased use of unmanned robotic
space, arguing that they will serve as more efficient explorers of planetary surfaces
than astronauts. The next giant leap, then, will be taken with robotic feet.
At the core of Crawford's argument is that human beings are much better at performing the type of geological fieldwork that makes planetary exploration scientifically valuable: they're faster and significantly more versatile than even the most advanced autonomous probes. "People who argue for robotic exploration argue for more artificial intelligence, the capacity for robots to make more complex decisions that somehow leads to increased efficiency," explains Crawford. "But one of the things that make them cheap is miniaturization.You can make robots more intelligent and efficient to a certain point, but they wont get smaller and therefore cheaper." With miniaturization, he explains, comes a depletion in the number of scientific instruments a probe can carry, the number of samples it can collect, and its ability to cover more ground. " [Mars rovers] Spirit and Opportunity are fantastic things on Mars, but the fact that they've traveled as far in eight years as the Apollo astronauts traveled in three days speaks volumes." At a certain point, the costs of developing 'smarter' (but not better equipped) autonomous rovers will exceed the meager gains in scientific collection and outstrip existing scientific budgets.
The advantages of human over robot explorers are recognized in the planetary sciences community: a 2005 report by the Commission on the Scientific Case for Human Space Exploration noted that "the expert evidence we have heard strongly suggests that the use of autonomous robots alone will very significantly limit what can be learned about our nearest potentially habitable planet." Steve Squyres, the Principal Investigator for the Mars Exploration Rovers Spirit and Opportunity, conceded in his book Roving Mars that "[t]he unfortunate truth is that most things our rovers can do in a perfect sol [a martian day] a human explorer could do in less than a minute." But Crawford also expresses concerns over the capacity of robots for "making serendipitous discoveries."
"We may be able to make robots smarter, but they'll never get tot he point where they can make on the spot decisions in the field, where they can recognize things for being important even if you don't expect them or anticipate them," argues Crawford. "You can't necessarily program a robot to recognize things out of the blue."
The other downside of a shift towards robotic exploration is the decline of samples, the real meat of the planetary sciences. Robotic expeditions have always been one-way trips: the probes go, land, take readings, and don't come back. But the collection and prolonged study of planetary samples are real drivers of scientific knowledge, which Crawford measures in terms of published scientific literature:
Several things are immediately apparent from Figure 2. Most obvious is the sheer
volume of Apollo's scientific legacy compared to the other missions illustrated. This
alone goes a long way to vindicate the points made above about human versus robotic
efficiency. The second point to note is that the next most productive set of missions
are the lunar sample return missions Lunas 16, 20 and 24, which highlights the
importance of sample return. Indeed, a large part of the reason why Apollo has
resulted in many more publications than the Luna missions is due to the much larger
quantity and diversity of the returned samples which, as we have seen, will always be
greater in the context of human missions. The third point to note is that, despite being
based on data obtained and samples collected over 40 years ago, and unlike the Luna,
Lunokhod, or Surveyor publications, which have clearly levelled off, the Apollo
publication rate is still rising. Indeed, it is actually rising as fast as, or faster than, the
publications rate derived from the Mars Exploration Rovers, despite the fact that data
derived from the latter are much more recent. No matter how far one extrapolates into
the future, it is clear that the volume of scientific activity generated by the MERs, or
other robotic exploration missions, will never approach that due to Apollo.
"We're still benefiting from the scientific legacy of those few soil samples brought by the Apollo mission, but we can only do this because we went to the Moon, got these samples, and came back," says Crawford. "If we sent a rover to Mars along with a return vehicle, that would enormously increase its scientific impact, but that's hasn't been implemented yet because its still incredibly expensive. If a mission goes to Mars, lands in one place, bring back half a kilogram of Mars rocks, it will be immensely valuable, but compared to Apollo, which not only visited six sites (and many hundred of sites with the help of the lunar rover) but came back with 382 kilograms of lunar material, it sort of pales in comparison."
While robotic probes find a permanent home on a planetary surface, sending manned expeditions inherently means planning for a return trip. Would a manned trip to Mars, replete with a sample-laden return vehicle, yield a similar explosion in scientific literature? Crawford thinks so. "A Martian expedition would be 5 or 10 times more expensive than Apollo in real terms, but not so much more expensive that it would negate the added benefit of being able to collect samples. They'll bring back a much larger quantity and diversity of samples than a robotic mission, and this is especially important with regards to Mars: there are reasons for wanting more lunar samples, but Mars is a much bigger and much more geologically diverse planet, with a much more complicated geology so much more inconceivably complicated history than the Moon, we won't get a full sense of its history or evolution just by scraping around on the surface with these smalls robot probes."
The scientific impact of these moon rocks is compelling: our whole
chronology of the solar system is built on the radiometric dating of the
Apollo samples. "The top scientific benefit is that it's been possible
to date areas of the lunar surface. We have this curve that plots crater density versus age, which we can use to get an estimated age of
virtually anywhere else in the Solar System," explains Crawford.
"The last major eruption of Olympus Mons [on Mars] was 400 million years
ago, and the only way we have this measurement is because of Apollo
So why, then, are scientists resigned to sending probes and rovers to the corners of the galaxy? Scientists, argues Crawford, tend to look at the enormous costs for Apollo, which nobody will ever be able to afford again, as an artificial baseline for gradual streamlining of space exploration. This is the wrong approach to take "There's lots of collective amnesia as to how efficient Apollo really was, which is really the only example of exploring the surface of another planet," explains Crawford. "An enormous amount was achieved in a very short total contact time with the lunar surface."
Planners feel the microscopic formations in Mars meteorite ALH84001, found in Antarctica, and the highly diverse samples of rocks believed to have been strewn about by ancient rivers seen at the Mars Pathfinder landing site, provide a strong motive for sending human exobiologists and geologists to the Red Planet. [Pat Rawlings/NASA]
But Crawford recognizes that, despite its benefits for scientific research, manned missions are subject to domestic forces and rarely undertaken for the sake of science alone. The United States was willing to shoulder the enormous costs of the Apollo mission because of the geopolitical and economic interests (namely, besting the Soviet Union), an argument advanced most recently by science communicator Neil DeGrasse Tyson.
"Science was the beneficiary of a human spaceflight mission that was undertaken for geopolitical purposes," explains Crawford. "The total costs is large, but the best way for scientists to look at it is not 'this is a science function.' They need to look at Apollo as the confluence of geopolitical, industrial, and social factors. You need all of these things to spend the money necessary."
Crawford's theory, then, is not necessarily targeted towards the general public: he recognizes the difficulty of justifying an expensive manned mission with no immediate economic benefit (although he notes notes that the 1987 NASA procurement of $8.6 billion generated a turnover of $17.8 billion and created 209,000 private sector jobs, according to an article in Nature), especially in the throes of an global economic downturn. His main argument, then is those scientists consigning themselves to a future of interstellar probes are shooting themselves in the foot. Ventures like the James Webb Space Telescope may hit the ceiling for government expenditures on purely scientific ventures, but researchers and scientists can -- and should -- try to make the case for manned spaceflight in other contexts, if only for the sake of maximizing the scientific gains made from planetary exploration.
"Humans bring a net benefit to space exploration that, in my opinion, outweighs the costs," says Crawford. "But people need to realize that the overall case for manned spaceflight is multifaceted, a totality woven out of these different strands, of which science is one. Industry, innovation, inspirational value -- all of these factors must be addressed before manned spaceflight can return."
The permissiveness of Republican leaders who acquiesce to violence, collusion, and corruption is encouraging more of the same.
In the annals of the Trump era, May 25, 2017, will deserve a special mark. Four remarkable things happened on Thursday, each of which marks a way that this presidency is changing the nation.
The first remarkable thing was President Trump’s speech at the NATO summit in Brussels. Many European governments had hoped—which is a polite way to say that they had suggested and expected—that Trump would reaffirm the American commitment to defend NATO members if attacked. This is the point of the whole enterprise after all! Here’s how it was done by President Obama at the NATO summit after the Russian invasion of Crimea:
First and foremost, we have reaffirmed the central mission of the Alliance. Article 5 enshrines our solemn duty to each other—“an armed attack against one … shall be considered an attack against them all.” This is a binding, treaty obligation. It is non-negotiable. And here in Wales, we’ve left absolutely no doubt—we will defend every Ally.
She lived with us for 56 years. She raised me and my siblings without pay. I was 11, a typical American kid, before I realized who she was.
The ashes filled a black plastic box about the size of a toaster. It weighed three and a half pounds. I put it in a canvas tote bag and packed it in my suitcase this past July for the transpacific flight to Manila. From there I would travel by car to a rural village. When I arrived, I would hand over all that was left of the woman who had spent 56 years as a slave in my family’s household.
The condition has long been considered untreatable. Experts can spot it in a child as young as 3 or 4. But a new clinical approach offers hope.
This is a good day, Samantha tells me: 10 on a scale of 10. We’re sitting in a conference room at the San Marcos Treatment Center, just south of Austin, Texas, a space that has witnessed countless difficult conversations between troubled children, their worried parents, and clinical therapists. But today promises unalloyed joy. Samantha’s mother is visiting from Idaho, as she does every six weeks, which means lunch off campus and an excursion to Target. The girl needs supplies: new jeans, yoga pants, nail polish.
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At 11, Samantha is just over 5 feet tall and has wavy black hair and a steady gaze. She flashes a smile when I ask about her favorite subject (history), and grimaces when I ask about her least favorite (math). She seems poised and cheerful, a normal preteen. But when we steer into uncomfortable territory—the events that led her to this juvenile-treatment facility nearly 2,000 miles from her family—Samantha hesitates and looks down at her hands. “I wanted the whole world to myself,” she says. “So I made a whole entire book about how to hurt people.”
Maine attached work requirements and time limits to its safety net, intensifying poverty in the state.
ORLAND, Maine—In the eyes of the state of Maine, Laurie Kane is an able-bodied adult without dependents, and thus ineligible for most forms of government support. In her own eyes, it is hard to see how she is going to find housing, work, and stability without help.
Kane is struggling to put her life back together amid a spell of homelessness that has lasted for three years. She has a severe anxiety condition, along with other health problems, and had suffered a panic attack on the day I met her. But she had not managed to sign up for MaineCare, the state’s Medicaid program, because she cannot get a doctor to certify her as being disabled. That’s not because a doctor has evaluated her and found her to be fine, but because she’s been unable to get a doctor’s appointment. “I was denied MaineCare because I’m considered an able-bodied person,” she told me. “A lot of people say, ‘Well, you can just get free care.’ They say, ‘You can go to a clinic with a sliding-fee scale, which would be $20 a visit.’ But what if I can’t come up with $20?”
The president’s business tells lawmakers it is too difficult to track all its foreign revenue in accordance with constitutional requirements, and it hasn’t asked Congress for a permission slip.
Days before taking office, Donald Trump said his company would donate all profits from foreign governments to the U.S. Treasury, part of an effort to avoid even the appearance of a conflict with the Constitution’s emoluments clause.
Now, however, the Trump Organization is telling Congress that determining exactly how much of its profits come from foreign governments is simply more trouble than it’s worth.
In response to a document request from the House Oversight Committee, Trump’s company sent a copy of an eight-page pamphlet detailing how it plans to track payments it receives from foreign governments at the firm’s many hotels, golf courses, and restaurants across the globe. But while the Trump Organization said it would set aside all money it collects from customers that identify themselves as representing a foreign government, it would not undertake a more intensive effort to determine if a payment would violate the Constitution’s prohibition on public office holders accepting an “emolument” from a foreign state.
Returning to her alma mater to celebrate the class of 2017, she acknowledged her defeat—and offered a vision for the next generation of women leaders.
On Friday morning, along with the families of graduating seniors, hundreds of Wellesley College alumnae flocked to the school’s suburban Massachusetts campus in order to see Hillary Clinton, class of 1969, take the stage. Local alum groups hosted watch parties, starting early on the West Coast, and thousands of alums across the country live-streamed the event at their desks (myself included).
Long before some Americans took comfort in Clinton spottings in the woods, Wellesley alums have been known to track her spottings on campus, including her reunion visit in 2014, when her 2016 presidential bid was still just a rumor, and more recently at a private event in March when she spoke with students about activism and organizing.
The Republican bill would decrease access for millions, and in the process dismantle the tools used to fight substance abuse.
The middle of an unprecedented nationwide opioid epidemic might seem like a strange time to slash public funding for substance abuse, but that’s exactly what Republicans intend to do.
The American Health Care Act, which passed the House in early May and will soon be debated in some form in the Senate, will mark a major shift in national policy for opioid treatment, as well as for mental health, behavioral health, and substance abuse across the board. And it would come just after the Affordable Care Act began to create the first semblance of a true national safety net for those health issues.
Medicaid is the single largest source of funding for mental health and substance abuse treatment in the United States, and the Affordable Care Act’s expansion of the program to low-income adults was the first time there was some semblance of a national structure for treating mental health and substance abuse issues. Many people with severe substance abuse and mental-health issues also have low or no incomes or are homeless, and before the ACA were often ineligible for public insurance through Medicaid. So for that group especially—but also for millions of people with inadequate insurance or whose pre-ACA Medicaid didn’t cover mental health and substance abuse services—the only reliable way to receive care was when problems became severe enough to merit admission into an emergency room or institution.
The television host is chalking up the loss to a liberal media crusade.
At least five advertising firms have pulled their commercials from the Sean Hannity Show on Fox News following the television host’s coverage of a false murder conspiracy. On Tuesday of last week, Hannity reiterated a now-debunked theory regarding the death of Seth Rich, a Democratic National Committee employee who was gunned down last summer in Washington, D.C. While local police suspect the shooting to be a botched robbery, Hannity claimed that Rich was murdered over his alleged ties to WikiLeaks. Moreover, Hannity argued on Twitter that the story could potentially discount any evidence of collusion between Russian officials and the Trump administration leading up to the 2016 U.S. presidential election:
When the FBI discovered a network of Bosnian-Americans giving support to terrorists, they also discovered Abdullah Ramo Pazara, a U.S. citizen and a battalion commander in Syria.
Abdullah Ramo Pazara had a craving for packets of instant hot cocoa. The Bosnian-American former truck driver was, at the time, a commander of an Islamic State tank battalion in Syria. Apparently, even foreign fighters who reject their former lives in Western countries for a chance at martyrdom for ISIS sometimes long for the creature comforts of their previous homes.
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In 2013, six Bosnian immigrants in the United States allegedly sent money, riflescopes, knives, military equipment, and other supplies to jihadists in Syria and Iraq through intermediaries in Bosnia and Turkey. According to the U.S. government’s allegations, individual ISIS fighters would make specific requests—mostly for money and military equipment—and the group would then raise funds and send supplies to Syria. The requests included what was surely an unexpected revelation of nostalgia—packets of Swiss Miss hot cocoa. By sending the cocoa mix and other supplies, federal prosecutors argue, these U.S.-based Bosnians provided what is known as “material support” to terrorists, in violation of the Patriot Act.