Centauri Dreams has always advocated a robust asteroid detection program to help us get an accurate census of objects that might endanger Earth. Thus I’m happy to report on promising events at the UK’s sole observatory dedicated to Earth-crossing asteroids. The Spaceguard Center in Wales has been offered a new telescope by the Institute of Astronomy (Cambridge), the light pollution in the latter location having reached the point where observations are seriously compromised.
Fortunately, there are parts of Wales with dark skies indeed. Thus the Schmidt instrument, useful for identifying objects moving against the stellar background, should be useful not only for searching but also tracking comets and asteroids. Absent funding sources in Wales or the UK government itself, the observatory turns to private sponsorship as the potential solution. We’ll keep an eye on how that effort goes — an estimated £54,000 ought to do the trick, and as this BBC report notes, the site’s possibilities as a tourist attraction may boost fundraising.
Looked at from an international perspective, it is stunning that there is so little coordination among scientists trying to identify Earth-crossing objects or deal with the threat once a danger is identified. Yet our growing knowledge of the role impacts have played in the development of life on our planet makes the need to prepare for the worst contingencies an imperative. Located near Knighton in mid-Wales, the Spaceguard Centre offers another option for finding a potential danger and, let’s hope, for educating the public about a threat to life that is all too real.
Remembering how Gregor Mendel could not get a major scientist to take his discoveries seriously, and thus his paper languished in an obscure journal for 30 years before other researchers did their own studies and ONLY THEN bothered to find Mendel’s work, I have to wonder if today’s astrophysicists are not in Mendel’s same scenario — that is, lacking the political oomph to garner the attention of those who could fund a global system that finds all space objects bigger than, say, five meters wide. Given that the cost of the Schmidt instrument is a trifle, I have to say it reflects poorly on the communication skills of the astronomers extant.
We know that a single asteroid strike would suddenly galvanize governments everywhere just as the 9-11 strikes started the so-called War on Terror (or as I like to say, War on Children for Oil.) So what does a world class astronomer have to say to a world class politician to get this funding NOW?
With all the National Geographic channel’s productions about “what if an asteroid strikes” you’d think that politicians long ago would be paranoid enough to fund this problem out of existence. What are they not getting that they, moment by moment, delay funding this simple solution?
Sorry, but I have to lay this at the feet of the astronomers today — just as hind sight would have us ask Mendel — “What were you thinking? A monk doing science? You need credentials to get attention from the “natural philosophers,” and why did you gain so much weight and make your bending over in the garden too hard to do? Continued studies might have gained the momentum to save humanity the extra 30 years of waiting for genetics to “get off the ground?”
What questions like the above will politicians ask of astronomers AFTER a strike? What political or, heck, psychic powers must today’s astronomers mindfully gain to get the credibility-in-the-eyes-of-the-money-people?
I don’t expect an answer, because, hey, astronomers today are crying constantly for more money, and we read again and again about unfunded but extremely worthy projects — almost all of which could be paid for with a price tag that wouldn’t even have a line in the accounting overview of a typical military-industrial-complex project. One jet bomber’s price could buy what? Hey, there’s an idea: can someone make a list of the unfunded projects now-on-the-table that could be funded for the cost of a single jet bomber?
Edg
“What questions…will politicians ask of astronomers AFTER a strike?” Edg, good question, and one worth thinking about, particularly given the growing body of knowledge about the danger of near-Earth objects. I have no answer, but see our only recourse as continuing to hammer on the issue so that major technologies, like Arecibo’s planetary radar, continue to get funded, and more people become aware of the problem. A darker scenario is the one suggested by Clarke, that it will actually take a small strike (and let’s hope it’s small!) to draw attention to the problem. Rendezvous with Rama may be another instance of Clarke’s prescience.
Not sure this belongs in this thread, but here goes: why not build a base on an asteroid instead of the moon, and then take the “grand tour” around the sun, out past Pluto and beyond and then back again? The advantage is that these rocks are already going tens of thousands of miles per hour — all we have to do is hitch a ride. I’m thinking we could pull this off in less than ten years — don’t know which asteroid would have the ideal orbit for this — any suggestions?
Edg
Edg, to land on any body you first have to match your craft to its velocity. That means you are already in the identical orbit, so you don’t need the asteroid at all. Unless you have a need to anchor yourself to a chunk of rock or ice for resources or something else, there are likely more disadvantages than advantages. The moon is also usefully close since your crew will want occasional vacations back home.
If you still like the idea, one advantage of a body other than the moon is you don’t have to deal with that awful static-laden fine moon dust that gets into everything.
Hi Edg Duveyoung and Paul;
Thanks for your comments and feedback.
If by chance, we happen to notice a 100 meter wide class asteriod on a collion course with Earth, we might have little time to react to its impact. Such small asteriods might pop up on a proverbial moment notice. And so I post the following comments I made on a website at the following URL:
http://www.physicsforums.com/archive/index.php/t-129368.html
Given that a one megaton nuclear warhead releases the energy to fully vaporize 2 million metric tons of water ice or 2 million cubic meters of ice, and by virtue of many minerals’ and metals’ much lower heat of vaporization and specific heat compared to water, an equal volume of many of these much denser minerals and compounds could be vaporized by a one megaton device. I would have to say that if the energy of a one megaton nuclear detonation could be evenly distributed throughout a 450 foot diameter asteriod, the asteriod could be completely vaporized by such a device.
Note, that a surface detonation of only a one megaton nuclear warhead will produce a crater 200 feet deep and 1000 feet wide in hard rock, even in consideration that much of the blast energy of a surface nuclear detonation is instantly reflected back away from the ground. I would have to say that a robust deep asteriod penetrating one megaton nuclear warhead should be able to vaporize completely at least a 100 meter diameter asteriod. A 100 meter diameter asteriod would have a mass on the order of 1.5 million tons.
Such an asteriod hitting the surface of the Earth at a typical 20 Km/Sec would have a yield of (1.5 x 10 EXP 6)((7) EXP 2) tons of TNT or about 75 megatons which is almost as powerful as the most powerful publically agknowledged H-Bomb design of the former U.S.S.R. at 100 megatons. Such a 75 megatons explosion would be catastrophic if it happened in New York City, Mexico City, Tokyo, Beijing or other very large metro area.
Note that the thermal pulse of the Russian 58 megaton Tsar Bomba tested in 1961 in an airburst over a remote Arctic island location would have caused fatal third degree burns in humans at a distance of 100 kilometers from the blast epicenter. Although detonated 2.5 miles above the ground over the island, the rock crust beneath the blast was turned to ash. A woman who later visited the test site was amazed when she saw and noted that the blast zone was licked clean and shinny like an ice skating rink, all traces of uneveness in the rocks where melted and swepted away. Such an explosion’s thermal pulse is large enough in the extent of its effects to completely set ablaze the entire land mass of many smaller nations and several of the smaller states within the U.S..
Clearly even only a 100 meter diameter asteriod, although not able to wipe out the human race, could produce totally unacceptable losses of property and human life. A direct nuclear strike by a typcial 0.475 megaton to one megaton yield warhead may be our only option in dealing with 100 meter diameter class asteriods on relatively short notice. Note that perhaps a couple to a few W-88 nuclear warheads such as those stationed aboard U.S. Ohio Class SSBM boats could probably do the job. The yield of one W-88 warhead is about 0.475 megatons or 475 kilotons.
Much larger asteriods might be destroyable with nuclear devices of much higher yield given enough lead time to construct and/or deploy such devices. Super large asteriods could be deflected potentially with a high yield stand off neutron bomb detonation wherein the intense neutron flux would penetrate several meters into the asteriod vaporizing the surface layer of the asteriod thus allowing the momentum imparted to the asteriod for course correction to be maximized by the recoil produced by the reaction between the hot very high pressured vaporized surface layer in gaseous form and the bulk of the remaining asteriod.
Thanks;
Your Friend Jim
I’ll second what Ron S says: Because of the need to match velocities, hitching a ride on an asteroid for Solar System exploration isn’t really useful. But Edg, you may be recalling older concepts of using hollowed out asteroids as long term habitats for interstellar missions, a much different idea, but one that may still prove attractive compared to building a ‘worldship’ from scratch.
Hi Paul;
I like the hollowed out asteriod idea for long term manned interstellar missions. Using large Iron/Nickel type asteriods would prove an excellent way to provide radiation shielding and shielding from very small interstellar debris. Larger debris obviously could be taken care of by energy beams be they electromagnetic or charged particle beams.
I really liked the Star Trek eposode in the original series that featured a similar vessel.
Thanks;
Your Friend Jim
I was thinking, why “pay” for getting all that mass off the earth when lots of fuel, water, etc. is already out there to be “attached to” — something like that — didn’t think of hollowing it out since that would be much more than ten years down the line. Didn’t think it all out properly though, so, sigh. But James’ descriptions of atomic power triggered my memories of “Footfall” where the elephantesque aliens dropped rocks/bombs as their weapon, and I’m still wondering why military minded folks wouldn’t have clarity, by now, about space rocks — seems to me that James’ thinking above would have been presented by an august group of scientists long ago to them and a small budget immediately agreed to.
James, one thing about blowing up the rocks — even to vapor — is that the vapor too must be widely dispersed or the radioactive rain of a debris cloud would hit us with big consequences despite the ELE having been avoided. I’m betting we’d have to blow it up “way way out there” for that to work — in order to give the cloud time to “thin out.” Then, if it’s that far out, why not just attach a solar sail, or implant a rocket engine, or do the “nearby object’s gravity pulls the rock slightly off course” techniques?
Edg
Edg
Hi Edg;
Thanks for your input. I must say I never carefully considered the effects of the vapor clould impinging on the Earth’s atmsophere and so I welcome your respective comments. Such a clould could indeed be a risk, perhaos even a greater risk than if the asteriod would hit some remote region like the one over Tunguska Russia in 1908.
Perhaps implanting a very large chemical rocket engine to gradually push it out of the way or implanting a nuclear ion rocket such as a large radio-thermoelectric powered ion rocket could be used to gradually push it out of the way. Using isotopes with a half life on the order of 100 years might allow a sizable fraction of the potential radioactive decay energy within the mass of radionucleid fuel to be converted to asteriod kinetic energy change or to velocity vector change assumming an effecient decay energy to thrust conversion mechansim.
Attaching a solar sail as you mentioned could also work.
Thanks for your insights on this important matter.
Your Friend Jim
Heh, rock vapour clouds are predicted on hot Jupiters. I’m not sure we’d really want to see them on Earth.
Asteroid to Make Rare Close Flyby of Earth January 29
NEWS RELEASE: 2008-012 Jan. 24, 2008
Scientists are monitoring the orbit of asteroid 2007 TU24. The asteroid, believed to be between 150 meters (500 feet) and 610 meters (2,000 feet) in size, is expected to fly past Earth on Jan. 29, with its closest distance being about 537,500 kilometers (334,000 miles) at 12:33 a.m. Pacific time (3:33 a.m. Eastern time). It should be observable that night by amateur astronomers with modest-sized telescopes.
Asteroid 2007 TU24 was discovered by the NASA-sponsored Catalina Sky Survey on Oct. 11, 2007. Scientists at NASA’s Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, Calif., have determined that there is no possibility of an impact with Earth in the foreseeable future.
“This will be the closest approach by a known asteroid of this size or larger until 2027,” said Don Yeomans, manager of the Near Earth Object Program Office at JPL. “As its closest approach is about one-and-a-half times the distance of Earth to the moon, there is no reason for concern. On the contrary, Mother Nature is providing us an excellent opportunity to perform scientific observations.”
Asteroid 2007 TU24 will reach an approximate apparent magnitude 10.3 on Jan. 29-30 before quickly becoming fainter as it moves farther from Earth. On that night, the asteroid will be observable in dark and clear skies through amateur telescopes with apertures of at least 7.6 centimeters (3 inches). An object with a magnitude of 10.3 is about 50 times fainter than an object just visible to the naked eye in a clear, dark sky.
NASA detects and tracks asteroids and comets passing close to Earth. The Near Earth Object Observation Program, commonly called “Spaceguard,” discovers, characterizes and computes trajectories for these objects to determine if any could be potentially hazardous to our planet.
For more information, visit http://neo.jpl.nasa.gov.