≡ Menu

A Space-Based Asteroid Telescope

One of the world’s largest impact craters (see below) lies under Mexico’s Yucatan peninsula, evidently a major player in the demise of the dinosaurs. Chicxulub is 180 kilometers in diameter, the subject of continuing research by the man who identified it, Alan Hildebrand (University of Calgary). So you could say Hildebrand has an idea what massive impacts from asteroids can do to the Earth’s surface, having studied the environmental effects caused by this one and mapping the crater’s structure to identify mineral, oil and gas resources. That interest has led Hildebrand into an ongoing asteroid hunt, and explains his current plans to build and launch a space-based observatory designed to look for near-Earth objects.

Approaching NEO

The scientist currently uses use a retrofitted satellite tracking telescope in NEO work here on Earth. The instrument, based at the University of Calgary’s Rothney Astrophysical Observatory (some 75 kilometers southwest of the city) is an extensive re-build, a Cold War era instrument whose motors were replaced, its mount and optics modified and its electronics brought up to speed several years ago at the cost of $500,000. The telescope has been in asteroid-spotting use ever since.

Image: What we’re all hoping to avoid, an artist’s conception of a near-Earth object heating up as it encounters the upper atmosphere. Credit: Melinda Wenner/Wired Magazine.

Taking the asteroid search into space in the form of the Near Earth Object Surveillance Satellite (NEOSSat), an event that could occur within two years, would create the first space-based asteroid telescope, one to be used not only for identifying potential threats but also for helping us firm up our inventory of asteroids near enough to the Earth for manned missions. Nor is the suitcase-sized microsatellite a costly investment, totalling $10 million. Its position in space should allow the observatory to block sunlight to look for objects between the Earth and the Sun that are otherwise difficult to see.

Because some of these asteroids come close to matching Earth’s orbital speed, a robotic or manned asteroid mission becomes a distinct possibility. That would offer not only useful information about the early Solar System — such asteroids being remnants of same — but would also help us take the measure of the kind of objects we might one day need to push out of Earth-impacting trajectories. Would nukes work? Gravitational tugs? Sooner or later we’ll fly a NEO mission because we need to understand the nature of these asteroids as we assess the various strategies for dealing with them.

NEOSSat has the potential of cataloguing at least 50 percent of the one-kilometer or larger NEOs that orbit largely between Earth and the Sun, as New Scientist reports. Interestingly, the magazine cites Timothy Spahr (Harvard-Smithsonian Center for Astrophysics) as saying that an even better idea (though obviously far more expensive) would be to place a NEO-watching observatory in orbit around Venus, where the inventory of inner system objects could be even more definitively compiled.

Addendum: Although I had original identified Chixculub as the world’s largest impact crater, reader James Davis Nicoll quickly corrected me. Both Vredefort (300 km) and Sudbury (250 km) are larger.

Comments on this entry are closed.

  • James M. Essig May 6, 2008, 21:08

    Hi Folks;

    WOW! Chicxulub at 180 kilometers in diameter!

    How would or could we deal with something that big or bigger on a collision course with Earth.

    I can imagine building a nuclear device which might somehow be driven into the asteriod like a wedge, hopefully without crushing the nuclear device. But man! the device would probably need to be detonated in a sub-surface burst to impart as much energy into the asteriod material as possible. I am talking about a big device, essentially at least one billion metric tons or roughly a billion cubic meters in volume.

    The device I am thinking of would be huge indeed. Perhaps it would be made of cheap frozen water which undegoes nuclear fusion after an extremely high mass specific energy density hydrogen bomb sets off a self propagating fusion reaction which would then propagate through the water bomb in a small fraction of a millisecond. If a hydrogen bomb with a spherically symmetric explosion could not generate the requisite temperatures and pressures to set off the water bomb, then perhaps a theoretical shaped charge nuclear device could generate the needed temperatures and pressures. Open literature suggests that a shaped charged neclear device could, if properly constructed, concentrate its blast energy greater than over 6 orders of magnitude with respect to a spherically symmetric device. Shaped charge conventional munitions are employed by modern armies to defeat heavy armour such as battle tanks and the like.

    Another option would be to attach huge nuclear rockets to the asteriod or huge mass drivers preferably nuclear powered inorder to maximize potential energy per delivered payload. We would have to try something for an asteriod this big, because if we did nothing, our gooses would be cooked for sure.

    Thanks;

    Jim

  • george scaglione May 7, 2008, 8:21

    jim stangely such a perdicament might be the very thing that would bring us all together! but i sure hope nothing like that actually happens anytime soon! in the future though when we have already developed some serious technology,maybe the situation would not be as serious.lol hope any really large asteroids will be polite enough to wait a couple of hundred years! ;) your friend george

  • James Davis Nicoll May 7, 2008, 11:53

    Isn’t Chicxulub only the third largest, after Vredefort (300 km) and Sudbury (250 km)?

  • Administrator May 7, 2008, 12:36

    James, right you are, and sorry for the mistake. I’ll amend the original post as well.

  • ljk May 7, 2008, 13:07

    NASA Considers Manned Asteroid Mission

    Written by Ian O’Neill

    What would happen if we spot a Near-Earth Asteroid (NEO) heading straight for us? Assuming we had enough time, we might be able to pull together a group of brave astronauts (or oil drillers) and send them to the asteroid just in the nick of time to destroy it… oh hold on, that sounds like the storyline for a Hollywood blockbuster.

    Actually, NASA is planning a mission to an NEO, but not because it’s aimed at us.

    An asteroid named 2000SG344 (which threatened the Earth in the year 2000) is being considered as the destination for the first manned asteroid mission. The asteroid astronauts will travel there, chasing the 28,000 mi/hr (45,000 km/hr) speeding body and then carry out experiments, living on it for up to two weeks. Why? To briefly establish a manned outpost, advancing science and technology toward the ultimate goal: Mars.

    In a study to be published in June, scientists at NASA’s Johnson Space Centre in Houston and Ames Research Centre in California will provide a rundown of their plans to use the future Orion spacecraft for this task, with a stop over of one- or two-weeks. I’m looking forward to seeing their recommendations for this ambitious development…

    Full article here:

    http://www.universetoday.com/2008/05/06/nasa-considers-manned-asteroid-mission/

  • george scaglione May 7, 2008, 14:11

    ljk,i never knew that! about the manned asteroid mission above that is! thank you very much.i just wonder in what year this might come to pass!?? if you have any idea please pass it along!and, as a stepping stone toward mars.EVEN BETTER!! the article you thoughtfully provided seems to indicate 2030… i was seriously hoping for sooner.but we will have to wait and see because :( at this point everything about space seems to be indefinate! especially if mr obama gets in. hedoes not seem to care for manned spaceflight all that much.anybody who can make me a liar on that…please do! i’d appreciate the news.all the best, george

  • James M. Essig May 7, 2008, 15:26

    Hi George;

    Thanks for your response.

    I certainly hope you are right about a couple of centuries warning time. It makes me wonder if any huge body out within the Kuiper Belt or Oort cloud has Earth’s name on it. Given that objects have been found in the Kuiper Belt have mass of the rough order of magnitude of Pluto’s, I just hope one such interlopper does not eventually wander too close to Earth. We seem to be safe from such bodies so far as the orbits of the minor planets discovered recently are beyond that of Pluto’s. Let’s keep our fingers crossed on this matter, however.

    Thanks;

    Your Friend Jim

  • James Davis Nicoll May 7, 2008, 21:05

    If I recall Hazards Due to Comets and Asteroids correctly, the mean time between impacts for what they called “supercomets” was on the order of a trillion years.

  • James M. Essig May 7, 2008, 21:57

    Hi George;

    A manned mission to the asteriods would be awesome indeed. I am curious about asteriods, not only in the sense of determining how to divert them or destroy them if necessary, but also for their potential mineral wealth. If I am not mistaken, these rocks can contain significant amounts of Iridium and God knows what ever else exotic elements and isotopes.

    I don’t think there will literally be a planetary Gold Rush to the asteriods, however, there might be even rarer element/isotopes that may have huge benefits for us here on Earth. Some superstrong alloys used in or proposed for military, NASA, and commercial aerospace vehicles are I believed alloyed with precious metals. Exotic semiconductor microchips comes to mind, also, as well as perhaps special photovoltaic cells, perhaps even doped PV cells with special applications that have not been developed yet.

    Heck, I’d be tempted to fork out a few K for a small precious metal bar formed from mined asteriodal material just as a novelty.

    Thanks;

    Your Friend Jim

  • david lewis May 7, 2008, 23:08

    ——–
    WOW! Chicxulub at 180 kilometers in diameter!
    How would or could we deal with something that big or bigger on a collision course with Earth.
    ———

    We might be able to divert such an object given sufficient warning, maybe 10 years. Though would we is another question entirely.

    One could imagine the world uniting and for a period giving up war, throwing all our effort instead into diverting the object. The intellectual and industrial effort of 6.5 billion people is nothing to laugh at.

    One can imagine one or more orion type vehicles in the megaton range being built. A vehicle able to transport massive amount of material to the object that is to impact the earth. It could maybe carry thousands of hydrogen bombs in the gigaton range that if exploded at the right distance from the object would give it some minor thrust. Or even having the orion ship land and act as a nuclear engine.

  • ljk May 8, 2008, 8:15

    DINOSAUR KILLER MAY HAVE STRUCK OIL

    The dinosaur-killing Chicxulub meteor might have ignited
    an oilfield rather than forests when it slammed into the
    Gulf of Mexico 65 million years ago, say geologists.

    http://abcmail.net.au/t/148534/687780/3175/0/

  • Zen Blade May 8, 2008, 15:50

    It turns out that this meteor probably didn’t kill the dinosaurs in the way we all think. There was some very interesting data presented at Rockefeller last week that really the pterosaurs were displaced by birds well before K-T, and although a few remaining species may have gone extinct, they were already on their way out. The dinosaurs were quite, quite possibly in a similar position with regards to mammals… although this data was far less developed.

  • forrest noble May 12, 2008, 16:13

    Hey George, Jim,

    Sounds like a very interesting mission and observatory. What I will be looking forward to is when a mission will be planned to land on some of these near-earth asteroids. One which has an elliptical orbit between roughly .8 AU to 2.8 AU, with an orbital periods ranging from less than 2 years to 6 years. If we spend the necessary time we could pick a “good one” to start with. I found at least 35 candidates in my recent research that seem to meet this description.

    One that comes reasonably close to both the moon and the asteroid belt. First we could install a space telescope on it. Then we could build a mechanized farming system inside of it to feed maybe up to 5 people for a 2 to 5 year stay. Build up the city from material from the moon and asteroid belt. We could transfer all the materials needed to build an entire scientific community space city around it for scientific investigations. Because of its regular orbit we could transfer materials between the moon, asteroid belt, mars, and earth just to start with. Transportation in general would be free for most of the journey. Jim, this could be the beginning of large space cities that you proposed that eventually might themselves, as a whole city, choose to meander off to another star system.

    We could colonize, take advantage of all of these near earth satellites without artificially putting any asteroids into such orbits which would worry all the environmental groups around the world, the weak of heart, the timid of spirit, the uneducated, and religiously concerned persons (Re. Armageddon, etc. but some would love it because they want Armageddon to come). When these asteroid cities would come “close” to the Earth we could unload and fly the contents down by shuttle or similar systems. It could have taxi craft to go from place to place picking up and dropping off large quantities of materials without ever landing except at its home port which would be one of these asteroid colonies. Seems relatively low cost to me. Using its orbital momentum to start with, in the proper calculated position, we could launch space craft from these colonies all over the place with relatively little fuel.
    A seemingly nice way to possibly preserve humanity along with frozen embryos of other humans for genetic variety including seeds, spores, and some frozen embryos of our animal buddies.

    what say you all?

    your friend forrest

  • James M. Essig May 13, 2008, 9:05

    Hi Forrest;

    Outstanding ideas! Given the large number of near Earth orbiting asteriods, such bodies would make great habitats and cities. I have never thought of the idea of setting up shop and farming facilities within the asteriods. I am sure your skills in engineering and advanced technical background would serve NASA well in any indeavors to utilize the asteriods.

    I mentioned this most excellent posting of yours to my Mother about 30 minutes ago and she said that she thought it was an excellent idea. She mentioned that such asteriods could serve as safe refuge facilities for troubled space craft such as in emergency situations that might arise en-route from Mars and even the outer planets.

    The idea of storing human embryos for genetic variety is a good one. If we had a Global catastrophy such as a nuclear war or very severe Global warming with massive human population die-off, the storage of genetically diverse human embryos within hollowed out asteriods, cryogenically, would help ensure healthy genetic diversity within the regrown human population. The asteriods would make excellent radiation shields for the embryos. Naturally, I would want to store embryos for our animal buddies too. It would be too much of a shame not to have cute kitty cats along in space as we venture out.

    Asteriods would make excellent fusion rocket propelled space vehicles which could easily reach the 0.1 C to 0.15 C limits that your PAN theory suggests as limiting values of ordinarilly shielded space craft. We could launch these space zondes all over the observable universe given enough time. I say let the fun begin.

    Thanks;

    Your Friend Jim