"If God wanted us to live in outer space he wouldn't have given us inner ears" so goes a clever quote put up by Michael Lind in his latest op-ed piece ('Why we should embrace the end of human spaceflight').
Lind, sometime columnist of salon.com, isn't known for necessarily being the brightest bulb in the media firmament, and his latest article pretty well confirms that. He argues that with the penultimate Shuttle launch coming up later this month, and only one more mission scheduled later, we ought to happily embrace the end of the American manned space program.
No more billions having to be spent and we can simply depend on the Russians, Japanese or hey....the Chinese....say to assist us when our GPS satellites or other items need repair. Doesn't anyone think this is effing pathetic? Well it is! Especially since at one time (not all that long ago) this nation LED the rest of the pack in courageous manned exploration and ingenuity in space tech applications. (For example, MRI machines are one byproduct of the space effort, as are so many other devices, inventions.)
So what happened? Basically, starting with Vietnam, the country squandered its essential resources on war hardware as opposed to space hardware. For example, the tab on Vietnam when it was all over came to $269 billion. What did we really get from it? Nothing! However, the negative impact was to cut short a fruitful Apollo Lunar program that might have seen us already colonizing the Moon by now, had we not also squandered trillions on other unncessary conflicts, from Iraq to Afghanistan.
Of course, to defend his premise, Lind uses arguments that have already been recycled by many others, including Physicist Steven Weinberg (in a Wall Street Journal piece 2 yrs. ago). His basic thesis is that the manned space program is not really critical to doing science such as unmanned robot craft (like the Mars Spirit Rover) can do, and hence if it’s cut out then more can be done via robotic probes to advance our knowledge.
I have no issue with the logic that robot probes advance our science more, but that doesn’t mean it’s wise to abandon the manned space program. It was Isaac Asimov in his Barbados lecture at Queen’s Park Theater in 1975 (see my previous blogs on this from July last year, also the attached photo) who said (tape recorded at time):
"Manned space exploration is not an option or a luxury. No sane, intelligent species in the cosmos willingly leaves all its ‘eggs’ in one basket, in this case on one planet. Any large asteroid, remember, could take us out with one strike. This could happen in 50 years or in 5,000 or 500,000. It doesn’t matter when, it will be the end of humanity if we choose to never explore and disperse ourselves….for our own protection."
But rather than heed Asimov's warning we've fallen into the trap of smugness and complacency that somehow it's no biggie. Even a number of commentators to Lind's piece appear to have taken the kool aid. One of them claimed that we have ample resources to detect them and with a little bit of technological acumen we could actually deflect them. He then provided a link, asserting: "Some suggestions are found here":
http://geology.com/articles/earth-crossing-asteroids.shtml.
After perusing the content I fired back at this critic of manned exploration:
Regarding whether an asteroid can be deflected, the author at the site clearly states:
"The answer is, yes, providing that it is small enough and that we have enough time to send a spacecraft to deflect it."
Thus, the deal breaker, as I myself pointed out is size-mass. I totally agree it may be feasible (provided we work on the technology) to employ some type of 'impact deflector' to stop smaller asteroids (< 1 km dia.) But this is totally useless against an Icarus- sized mammoth.
So once more we get to the bottom line: Either people will whine and cry and get on like little girls, bellyaching that space exploration is "too hard, too many risks, we humans are too fragile" etc. and we simply wait for the planet killer to wipe our miserable asses out, OR we act like the exceptional and intelligent species we claim to be and get this on track to make sure all our seed isn't confined here when the big one hits.
This argument is, obviously, following directly on from the one Isaac Asimov made at Queen's Park theater nearly 36 years ago. And it is as cogent then as it is now. It is hubris of the first order to believe that we can just “scotch” on this Earth, and never fret that we face no threats of extinction. A Torino-scale 10 asteroid, with a size on the order of just a quarter the asteroid Ceres would utterly destroy the human species and leave not a trace. Within the hour or so of its major interaction, all life on Earth would cease. The utter folly of never having extended ourselves to locate an alternate abode would become quite evident. But by then it would be way too late!
Even a Torino-9 asteroid would render most human life extinct as a result of the effects of a nuclear winter scenario: so many trillions of dust hurled into the atmosphere from the obliterating impact that sunlight would be reduced and a suffocating winter lasting decades ensue with the death of most plant life. With that extirpation, any remaining human life would certainly follow.
Granted, there IS an effect (which is only now being thoroughly studied using numerical codes in celestial mechanics) that has a remote chance of altering the path of an asteroid and sparing us. It's called the YORP effect and is produced when the surface of an asteroid say, is heated by sunlight and re-radiates the absorbed energy at thermal (e.g. infrared) wavelengths. The absorbed and emitted photons produce tiny torques on the body which can alter its spin rate and obliquity - BUT over planetary timescales. Thus, if some mammoth asteroid were directed toward us, the action of the YOPR effect acting over those time scales might cause a minute deflection- enough for us to escape. But I wouldn't put any money on that bet. None!
We have the proto-basis for deep space exploration and colonization as the MIT course site I cited shows. Nuclear powered propulsion could complete a trip to Alpha Centuari system in less than 45 years. Ion propulsion could do it in a little bit more. As long as we toss our hands up and cry and whine "Boo,hoo that's too hard!" we are sitting ducks and deserve to get exterminated by any Big one that arrives.
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