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01.09.04
OVER THE MOON PART III: Are there senior citizens who need prescription drugs on the Moon? Does the religious right favor a Moon base? How about illegal immigrants, would they be willing to take Moon jobs that Americans don't want?
I'm sitting here trying to figure out what possible reason--other than science illiteracy at the White House--there could be for George W. Bush to announce a plan to build a Moon base. Manned exploration of Mars is even crazier.
As this space pointed out last month, minimum weight at departure from low-Earth orbit for a stripped-down, austere Moon base might be 600 tons, and at current NASA launch prices, it costs $15 billion to place 600 tons into low-Earth orbit. Fifteen billion is NASA's entire budget--and that's just the cost to launch the Moon thing, not to build it, staff it, and support it.
An Apollo spacecraft at departure from low-Earth orbit for the Moon weighed about 45 tons, and the manned part was tiny--astronauts could not stand up or move inside--as most of the weight was fuel. Considering that Moon-base weight would also be mostly fuel, numerous launches firing 600 tons toward the Moon for the purpose of making a base would actually result in little more than a couple of metal huts, some supplies and some antennas. Program cost for the International Space Station, currently losing air pressure, is about $100 billion, and it does not leave orbit. A rough guess would be that to build something about the size of the International Space Station (ISS) on the Moon would cost at least twice as much, $200 billion. And the ISS itself is mainly cramped modules, supplies, and antennas.
What would astronauts at a Moon base do? I haven't the foggiest notion. Note that NASA has not so much as sent a robot probe to the Moon in 30 years, because as far as space-exploration advocates can tell, there is nothing, absolutely nothing, of value to do on the Moon. Geologists are interested in the Moon's formation. If there is ever a fusion reactor to meet the world's energy needs, the "helium three" on the Moon might prove useful, but fusion reactors are decades away from practicality, assuming they ever work. Spending $200 billion on a Moon base that does nothing would be pure, undiluted government waste.
And a Moon base would not only not be useful to support a Mars mission--it would be an obstacle to a Mars mission. Any weight bound for Mars can far more efficiently depart directly from low-Earth orbit than a first stop at the Moon; a stop at the Moon would require huge expenditures of fuel to land and take off again. The landing, in turn, would accomplish absolutely nothing--any mission components on the Moon would have been sent there from Earth, which means they could have departed directly for Mars from low-Earth orbit at a far lower cost.
In the days to come, any administration official who says that a Moon base could support a Mars mission is revealing himself or herself to be a total science illiterate. When you hear, "A Moon base could support a Mars mission," substitute the words, "I have absolutely no idea what I am talking about." Hint to reporters: If any administration official says "a Moon base could support a Mars mission," quickly ask, "What was the fuel fraction of the Lunar Excursion Module?" The answer is two-thirds. The LEM was what landed on the Moon during Apollo, and rocket propulsion has not changed much since, meaning that any future Mars spacecraft that stops at the Moon will expend two-thirds of its weight merely to land there and take off again. This renders the idea of stopping at the Moon on the way to Mars patent drivel. (Actually only about 15 percent of the descent weight of the LEM returned to lunar orbit, so the fuel-fraction calculation for a Moon stopover is even worse.)
Now, about this business of going to Mars. The Red Planet is plenty interesting, and men and women are sure to go there someday. For the moment, talk of a Mars mission is complete bunkum.
The Apollo spacecraft weighed 45 tons at departure from low-Earth orbit: it was gone for about ten days, carried three people and traveled about 800,000 miles total. A Mars mission would be gone for a minimum of a year (probably longer), carry at least six people (a geologist, a biologist, two physicians, and two career astronauts would be a skeleton crew), and travel 100 million miles or more total (the distance to Mars varies significantly depending on the launch year). So let's make a conservative guess and say an austere Mars-bound mission would weigh 25 times what an Apollo mission weighed, at departure from low-Earth orbit.
Now we're up to an 1,125-ton spacecraft and a $28 billion launch cost. (Probably a Mars mission would operate in segments, with several robot supply ships departing long before the manned craft; but for the cost calculation, the driving factor is total weight.) Twenty-eight billion is twice NASA's budget and, again, that is just the cost to launch the thing, not to build the ship, staff it and support it. When Bush's father asked NASA in 1989 about a Mars mission, the agency shot back a total program cost of $400 billion. That's $600 billion in today's money, and sounds about right as a Mars mission estimate. This is assuming no pointless stopover at the Moon; add a Moon base and the price zooms toward $1 trillion! We're getting into the range here of the national debt.
Some lunatics--I use that word in its astronomical context--have suggested a Mars mission could be done with a total spacecraft weight of only a couple hundred tons. Not if we want the people back! The manned part of a Mars ship would need incredible redundancy, perhaps two complete operating sections each capable of return to Earth, in case some failure occurs on the long transit. Radiation exposure will be far more of a factor in Mars travel than it was going to the Moon, which orbits within Earth's magnetic field, so many tons of shielding will be needed. The Mars ship will require a full operating theater and at least two surgeons on the crew, since what if the doctor is the one who gets injured? Probably an entire Mars ship would have to be assembled and sent there and back unmanned, just to ensure that the hardware works: meaning dozens of billions of dollars to fly an empty ship to Mars, and imagine how voters will like that. And even if the mission involves a very well-made spaceship with incredibly redundant system--and no president will authorize anything less, who would risk having to sit watching CNN show images of stranded astronauts dying on Mars?--there is risk a tragedy or fiasco.
One parting thought on the practicality of Mars. Spirit, the rover that just landed there, weighs half a ton. Spirit cost $410 million to build and place on Mars--and it's about the size of a refrigerator, and does not come back. Mars-mission proponents want to send something to the Red Planet the size of an office building, and bring it back.
What NASA needs right now is not an absurd, bank-breaking grand mission: It needs to spend a decade researching a safer lower-cost alternative to the space shuttle.
And why might George W. Bush endorse a Moon base or Mars mission? Either he's a science illiterate surrounded by advisors who are science illiterates, or it's a blank check for aerospace contractors.
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01.08.04
NONSENSE IS IN NO DANGER OF EXTINCTION: Species loss is indisputably a problem--it's among the few environmental issues where trends are negative, and among the few that really worries me--but the Nature study on the subject, being widely promoted in today's press, is a monument to nonsense. "WARMING MAY THREATEN 37% OF SPECIES BY 2050," The Washington Post says on page one this morning. Well, a lot of things "may" happen. Let's break down the nonsense in this study point by point.
First, though appearing in a prestigious science journal, this study, led by Chris Thomas of the University of Leeds, is nothing but computer modeling. No actual extinctions caused by global warming are established, nor is any confirmed relationship demonstrated between global warming and species loss. (Quick note: I accept most aspects of global-warming theory and favor greenhouse-gas restrictions.) The study is entirely a computer simulation, and as anyone familiar with this art knows, computer models can be trained to produce any desired result.
Computer models are also notorious for becoming more unreliable the farther out they project, as estimates get multiplied by estimates, and then the result is treated as specific. This is a 50-year projection, and everything beyond the first few years should be treated as meaningless statistically, given that tiny alterations in initial assumptions can lead to huge swings at the end of a 50-year simulation. Nature is a refereed journal, but it appears that all the peer-reviewers did was check to make sure the results presented corresponded to what happened when the computer models were run. There does not appear to have been any peer-review of whether the underlying assumptions make sense.
Second, Thomas uses his computer model to estimate that by the year 2050, as many as 1.25 million species will fall extinct, or have dwindled to such low populations that extinction cannot be prevented. (That's the high end of his estimate; actually the study projects a 15 percent to 37 percent extinction, a good sign of the squishiness of computer models, but press coverage and Thomas's comments focus on the high end.) Here is Thomas giving The Washington Post his estimate of 1.25 million species lost, and here is a summary of the study from the International Union for the Conservation of Nature (IUCN). Yet the International Union for the Conservation of Nature, the most important study organization in the field of species preservation, itself estimates that 12,259 species are threatened worldwide. (Here is the IUCN's "Red List" inventory of threatened species; the IUCN Red List is the most important resource in this field.) That's plenty bad enough, and that number alone convinces me species loss is a leading concern. But the jump from 12,259 imperiled species to 1.25 million extinctions is a hundredfold increase! The rate of species imperilment will rise in a short period to 100 times the current rate, and based solely on climate change? That sounds extremely implausible. In fact it sounds like cockamamie galimatias.
This is especially true in light of the third problem with this study, namely, that past episodes of global warming have not produced the mass-extinction that the Thomas computer models project. Global average temperatures have risen one degree Fahrenheit in the past century--a reason I accept most global-warming theory--without any significant effect on species. Several frog species including the Costa Rican golden toad (there are hundreds of frog species) may have been rendered extinct by climate change in the past century, but that's not even in the general zone of the kind of impact this study projects.
Estimates of global warming vary quite widely, as they too are driven by computer model, but the Intergovernmental Panel on Climate Change (IPCC), the most-cited source of global-warming projections, now expects somewhere around three to six degrees Fahrenheit of warming by 2100. (IPCC estimates are all over the map; set that aside for the moment.) Assuming that happens--many estimates are lower--we'd expect one or two degrees of warming by 2050. European temperatures rose naturally by one or two degrees at the end of the "Little Ice Age" of the fourteenth through nineteenth centuries. This rise did not cause a mass extinction in the region; in fact, it appears to have caused few or no extinctions. Why would the same level of temperature increase suddenly trigger a mass extinction now?
Finally, the study in question is dubious because extinctions don't seem to be happening at anywhere near the rate called for by other assumptions, mainly concerning habitat loss. Species-extinction theories say habitat loss, development, and logging should lead to rapid declines in species. All these factors are at play in the Pacific Northwest of the United States--and no animal species is known to have fallen extinct there in the last couple decades. (Several salmon species and other species of the area are imperiled.) This is significant because the Pacific Northwest is an elaborately studied area; far more is known about it than the tropical regions about which the Thomas study makes vague computer projections. Graduate students comb over the Pacific Northwest, knowing that tenure and academic renown will go to anyone who documents an animal species loss. And average temperatures are rising in the Pacific Northwest. For anything even remotely close to Thomas's 1.25 million extinctions to be a hard number, we should already be seeing the bow wave in the form of dozens if not hundreds of extinctions in well-studied areas like the Pacific Northwest. Instead we see, um, zero.
The IUCN's 12,259 estimate is plenty worrying in itself, and habitat loss is plenty worrying in itself. Habitat loss logically must represent a great threat to species, because most habitat loss cannot be adapted to, whereas species have been adapting to climate change since time immemorial. The case for species preservation should be made on hard ground, not on computer-generated squish.
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01.07.04
HOWARD AND HILLARY, PEAS IN A POD: What do Howard and Hillary have in common? I mean besides the impish grins and self-deprecating wits. They both pretend to be authors.
I've long found it troubling that Hillary Rodham Clinton insists on pretending to be the author of It Takes a Village and Personal History. Where is the harm in giving credit to those who did the actual work? People who refuse to give others credit when due are fundamentally suspect. John McCain's first book, Faith of My Fathers, openly credited Mark Salter as the true author; his second, Worth Fighting For, had Salter's name on the cover. People thought more of McCain for his sincerity. George W. Bush's campaign book, A Charge to Keep, openly credited Karen Hughes as the true author. Admitting who wrote the book you signed is called "being honest." Is Hillary's ego so beyond control that she actually believes people actually believe she is an author? Or is she incapable of self-honesty? Choose your unpalatable alternative.
Now comes word, via Susannah Meadows of Newsweek, that Howard Dean is pretending to be the author of his campaign book, Winning Back America. All Democratic contenders other than Carol Mosley-Braun have campaign volumes, and of them, Meadows reports, Dean is "the only candidate who doesn't acknowledge in his book that he got help with it. His ghostwriter, Ian Jackman, says he likes Dean and doesn't care about getting credit, but admits that a mention would have been nice."
Maybe Dean tells himself that all politicians lie about being writers, but as the McCain example shows, they do not. Besides, Dean's central claim is that he is not just another political faker. Is Dean's problem so much ego that he actually believes people actually believe he is an author, or is his problem that he is incapable of self-honesty? Choose your unpalatable alternative.
At some level this business of people in the limelight pretending to be authors is just another synthetic vanity for the celebrity, who wants the respect that comes with literary accomplishment but wants it the easy way: Pose for the cameras with a yellow legal pad as if deep in authorial contemplation; attend book signings surrounded by publicists; receive the rewards but skip the talent and lonely effort parts.
But set what all this says about contemporary culture aside and return to the man of the moment, Dean. His taking credit for someone else's work is not just a character flaw, though that is bad enough--it would get Dean thrown out of the University of Vermont. Why does Dean think that behavior that would get him thrown out of the University of Vermont is acceptable for someone who seeks to lead the nation?
There is a hero in Susannah Meadows's saga, and he is John Edwards. Senator Edwards put the name of his ghostwriter, John Auchard, on the cover of his book Four Trials. This shows truthfulness, and speaks well for Edwards as a person of integrity. No wonder he's trailing in the polls.
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01.06.04
ARE WE ALONE?: As the plucky Spirit rover scans the surface of Mars and sends back high-resolution images of dust and rocks, once again human beings wonder: Are we alone in the universe?
SETI searches have been ongoing for four decades--read Amir Alexander's comprehensive history of SETI at the Jet Propulsion Laboratory website. (Despite its name, JPL is the primary designer of space probes.) Various radio telescopes have methodically scanned our galaxy, the Milky Way, for artificial radio signals, and heard nothing. Astronomers have inspected the galaxy for unnatural markers such as polygons of laser light--theorizing such beacons might be built by advanced beings seeking companionship--and seen nothing. Researchers have looked for the spectral lines of artificial nuclear reactions, and not seen them. Some nearby galaxies beyond the Milky Way have been scanned, with nothing seen or heard. Galaxies are huge--about 100 billion suns on average--so much might be overlooked. And it may be that other beings don't want to be found, or use communications media we have not yet guessed. But as far as researchers have been able to tell, no signal not of nature's making emanates from anywhere in the enormity of the cosmos. The stars are silent.
This has raised a worry among researchers that even in the vastness of the cosmos (50 billion to 100 billion galaxies, maybe an infinite number) the conditions for life may be surprisingly rare. Most stars are not stable over very long periods like Sol, our sun. Stars that are like our sun may be unlikely to have Earth-like planets, the one kind of planet we know can host life. A few decades ago, an astronomer named Michael Hart calculated how far from a Sol-like star an Earth-like planet must be in order to have liquid water on its surface and the right temperatures and pressures for carbon-based life. What Hart found was that the planet would have to sit almost exactly where Earth sits, or it would become too hot or too cold. Venus and Mars seem evidence of this. Venus, the next planet closer to the sun, has a runaway greenhouse effect and 900-degree Fahrenheit surface temperatures; Mars, the next planet out, has surface temperatures about the same as Antarctica, and its water appears locked in a runaway ice age. Hart called the star-distance relationship that allows for liquid water and carbon chemistry the "continuously habitable zone." He supposed that for a Sol-like star, the zone is less than one percent of possible orbits.
Later other researchers, including the late Carl Sagan, revised Hart's calculations to suggest that the continuously habitable zone could be as high as five percent of possible orbits for a Sol-like star, but this still implies that the conditions for life based on carbon chemistry may be exceedingly uncommon in the cosmos. Most planets don't orbit stable long-lived stars; most planets aren't Earth-like (in this solar system, only three of nine are: Earth, Mars, and Venus); and of those Earth-like planets that do exist, 95 percent will fall outside the habitable zones of solar systems.
Now comes a study published in Science, led by Charles Lineweaver of the University of New South Wales, attempting to estimate the "galactic habitable zone," or the share of the typical galaxy that is hospitable to carbon chemistry. Galactic centers, Lineweaver supposes, could not allow living things like us to evolve: Radiation levels in the central areas of galaxies are fantastically high owing to frequent supernova explosions, while comets constantly rain down on planets. The outer areas of galaxies aren't hospitable, either. Almost all matter is gaseous, with heavy elements too rare for planets to coalesce.
Taking these factors into account, Lineweaver's team estimated that the "galactic habitable zone," the area beyond the tumultuous center but not on the diaphanous outskirts, is only 10 percent of the Milky Way. Obviously, Earth is in this favored zone. But if only 5 percent of planets have the right relationship to their stars to host life, and only 10 percent of stars are in a habitable zone to begin with--well, you get the picture. Add in that science still doesn't have the slightest idea what causes life to begin, and even in a galaxy of 100 billion suns, living things similar to us may be rare.
Finally, consider that intelligent beings may be rare in time as well as space. Earth life appears to have taken about 4 billion years from first cell to self-awareness, but it's only been 7,000 years from controlled agriculture to the nuclear bomb. Assuming Earth is typical, life may require incredible amounts of time to reach intelligence, and then quite rapidly advance to the ability to destroy itself--or, alternatively, evolve to some higher level. Thus the enormity of a galaxy may sponsor many intelligent civilizations, just not at the same time; the odds would be low that two planets would be in their space-probe-building period at the same moment. Evolving life may be abundant throughout galaxies, while intelligence in its technological phase is flashing in and out of existence very rapidly by cosmic standards.
This brings me to a haunting thought about the Lineweaver study. It estimates that the Milky Way's "galactic habitable zone" emerged about eight billion years ago. Our sun did not even form until about three billion years later; most Sol-like stars in the habitable zone are, on average, a billion years older than Earth's sun, the study supposes. If most of the stars in the galactic habitable zone are far older than Earth's sun, and if our evolutionary sequence is typical, this suggests that most of the intelligence our galaxy was destined to host has already come and gone: destroyed itself long ago, or long ago evolved beyond technological existence to some higher plane.
If you'd like far more on the topic of whether humanity is alone in the cosmos, including the religious implications, see my 1988 Atlantic Monthly story.
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PRESUMED GUILTY UNTIL WE IGNORE HIS INNOCENCE: It is now three weeks since the Danish Ministry of Science repudiated an attack by one of its committees on environmental author Bjorn Lomborg; see my December 19 entry for details. And although The Washington Post gave prominent A-section attention when the charges against Lomborg were made--DANISH PROFESSOR DENOUNCED FOR "SCIENTIFIC DISHONESTY"--the Post has yet to say a peep about the charges being withdrawn. So, Washington Post: When someone is accused that's a big story, and when the same person is vindicated by the agency that supervises the accuser, that's no story? Pretty cheesy, Post.
The New York Times, which also lent prominence to the accusation against Lomborg, gave prompt and fair coverage to the withdrawal of the accusation. Science magazine, the world's leading technical journal, reported Lomborg's vindication. Now how about you, Washington Post--only accusations count as news? We throw mud but we don't wash it off?
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DECEMBER 19 UPDATE: In the December 19 item mentioned above, I said, regarding another science dispute unrelated to Lomborg, that the editor of the technical journal Climate Research was "forced to resign" because he'd run an article casting doubt on global-warming doomsday theory. That's not what happened. An incoming editor of Climate Research wanted to print an editorial denouncing the article; when the publisher said no, the incoming editor resigned. See his own account of the event. Sorry my description of the chain of events was off.
The rest of the item on the Climate Research flap remains worth thinking about. There remains an atmosphere of anti-intellectualism directed against global-warming doubters, which backfires by diverting attention from the ever-stronger scientific case for greenhouse-gas regulation.
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01.05.04
THE BCS MELTS DOWN: "They're doomed!" my eight-year-old, Spenser, exclaimed when he saw purported number-one Oklahoma come out in the shotgun formation near its own goal line on the first possession of the second half at the Sugar Bowl, college's purported championship last night. And so they were. Oklahoma's Heisman-winning quarterback Jason White promptly threw an interception returned for a touchdown, and plucky underdog LSU went on to win the BCS crown.
More on the BCS in a moment; first, the absurdity of Oklahoma. Note that an eight-year-old immediately recognized how silly it was for the Sooners to be in the shotgun near their own goal line in a close game. But then, Oklahoma's season has been all about running up the score--it beat Texas A&M; 77-0, for example--and constant passing from the shotgun formation helps run up the score. Tactical problem: You can't run up the score when you're behind. Oklahoma's offense is designed with the goal of running up the score against second-echelon teams like the Aggies. When Oklahoma met an equal, Kansas State, in the Big 12 championship, the Sooners got pounded. Meeting an equal last night, Oklahoma lost again. I found it refreshing that the team the computers said was best looked awful, while the two teams that human beings liked--USC and LSU--looked great in the year's top bowls. Oklahoma, one suspects, believed the computers and thought its challenge was to win 50-3. Even the eight-year-olds saw through that.
Now, to the Bowl Championship Series. Presidents of universities not on the BCS gravy train, which is most universities, have been lobbying Congress to outlaw the BCS cartel. Congress should stand clear; the absurdity of collegiate football finances is a private matter. The BCS, however, now stands exposed as a sham.
Supposedly devised to ensure that the two best college teams meet in the season's final bowl, in two of the last three years the BCS has chosen for the final bowl teams--Nebraska in 2001, Oklahoma this year--that didn't even win their own conferences! Nebraska finished third in its own conference, and nevertheless was tabbed for the 2002 BCS championship game; Oklahoma was selected despite losing its conference title event by an embarrassing 35-7.
There was an easy way to tell Oklahoma was a Potemkin team--check its schedule, and find that during the regular season the Sooners played seven home games versus only five road games. Football-factory schools maximize earnings by playing at home; many essentially buy off lesser teams, offering an extra payment to play them at home. In turn, bonus home games inflate performance, since football teams are much more likely to win at home than on the road: When Oklahoma was forced on the road at season's end to appear in the Big 12 title event and then the Sugar Bowl, it promptly lost both. The Nebraska team the BCS tabbed two years back had played eight games at home versus just four on the road! But the BCS formula was devised not to recognize gimmicks like this, in order to guarantee that a few insider favorite schools such as Nebraska, Oklahoma, and Miami would play in the BSC finale, which is also the year's highest-revenue game.
So last night the sportswriters (via the Associated Press poll) voted for USC as number one, while the college coaches (via the USA Today/ESPN poll) "voted" for LSU. The latter "vote" is meaningless, as the American Football Coaches Association signed a contract with the BCS obliging the USA Today/ESPN poll to choose the winner of the BCS game as number one. If coaches could actually vote, rather than be bound by this Stalinist arrangement, USC would be the consensus top team.
All of which shows the BCS system has never been anything other than a financial mechanism designed to channel money to a few favored schools. But Congress should not intervene. The more the BCS bowl-rigging helps people understand that big-college football is about money, the better.
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