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During the past 24 hours, the Earth has been hit by about a million small meteoroids – most of which burned up in the atmosphere as shooting stars. This happens every day. And occasionally – once every 10,000 years or so — a really big asteroid (1 km in diameter or larger) comes along and smacks Earth with an extinction-level impact. That idea might cause some of us to lose some sleep. But in between are other asteroid hits that occur every 200-300 years where a medium-sized chunk of space rock intersects with Earth’s orbit, producing a Tunguska-like event, or worse.
“Those are the objects we are concerned with,” said former Apollo astronaut Rusty Schweickart, speaking at a 3-day workshop in Darmstadt, Germany which focused on plans and recommendations for global coordination and response to an asteroid threat. “We need to take action now to bring the world together and recognize this as a global threat so that we can make a cooperative international decision to act to extend the survival of life on Earth.”
There are likely about one million Near Earth Objects out there that could do substantial damage if one hit the Earth. This isn’t anything new – Earth has been in this same environment for billions years.
“What’s new is that we have now opened our eyes via telescopes and are seeing something flying by our heads, so to speak,” said Schweickart during a media event at the workshop. “When you see something flying by your head, you duck. It turns out we have the capability of ducking and causing these objects to miss us. Because we now know about this threat and because we can in fact prevent an impact, we then have a moral obligation to do so.”
Former astronaut Tom Jones, who also attended the workshop, told Universe Today that NASA hopes to find all the 500 meter objects within a few decades, “and thus through action be able to prevent an impact from that large an object, removing it from the overall asteroid hazard. Smaller objects are much more numerous (the approximately million NEOs mentioned above) and can cause city-size damage. We’ll have to search diligently for those in the coming decade and it’ll be several decades before we find those hundreds of thousands of 30-meter sized -subTunguskas.”
Schweickart discussed in a recent Universe Today article that we do possess the technology to move asteroids or change their orbits, and that this technology does need to be tested, and tested soon. But since an impact event could affect the entire world, the decisions on policies and international agreements about asteroid mitigation could actually pose a bigger challenge in dealing with an asteroid threat than putting the technology together.
“Bureaucracy is the most likely reason we will be hit with an asteroid in the future, not the technology,” said Schweickart. “That is an audacious statement to make, but if we can get past that and do our jobs right we should never be hit in the future by an asteroid that could threaten life on Earth. And it’s going to be a heck of a challenge.”
The Mission Planning and Operations Group (MPOG) workshop included astronauts and space scientists and was the latest in a series of workshop designed to offer suggestions to the UN Committee on the Peaceful Uses of Outer Space. Included were representatives from NASA, ESA, the Secure World Foundation and the Association of Space Explorers. They are working on defining future planning tasks and studies for the Group that will later be merged with findings of other experts to create a final report to the UN committee. This report will recommend how to react to an impact threat.
But there are issues such as, how changing an asteroid’s orbit could make it miss one area on Earth and instead hit another area.
“The issue of NEOs is an issue that the United nations has been considering for 10 years or so,” said Sergio Camacho, representing the UN Committee. “The reason it has to go through the UN is that when we make a decision, whatever action is taken might affect others and put them at risk where they are not at risk at the beginning. That can’t be a unilateral decision, and we need to pool the resources of space agencies in order to address the problem. It will be within the framework of the UN that we will be able to master this cooperation.”
Schweickart and the Association of Space Explorers, have been working on this issue for over 9 years and are just now beginning to see a little headway in the bureaucratic process. Everyone at the workshop agreed that political decisions and political awareness is something that has to be taken seriously.
“Two weeks ago a small object passed in between the Earth and the Moon,” said Schweickart,“ and on Halloween an object half a kilometer in diameter Is going to pass within five lunar distances of Earth — in terms of astronomical distances, that is very close. These things are happening, but I hope we areable to act soon and act responsibly without having to have a reminder” – meaning the wake-up call of an actual impact and not being prepared for it.
For more information:
The MPOG workshop (where you can watch the press conference)
Tic-tok-Tic-toc…
“….on Halloween an object half a kilometer in diameter Is going to pass within five lunar distances of Earth….”
The object in question is 2003 UV11. SpaceWeather.com is reporting that this object, about 600 meters wide, is due to pass within 1.2 million miles tonight (and it is being pinged by Arecibo & Goldstone). The asteroid will appear as a swift moving 12th magnitude ‘star’ in the constellation Pegasus. A Youtube video has images, movies, a 3-D rendering of the circumstances and more info: http://www.youtube.com/watch?v=drikZqysHBQ
Ian Musgrave has an excellent resource page for this encounter (including full info for planetarium software): http://astroblogger.blogspot.com/2010/10/asteroid-2003-uv11-zips-past-tonight.html
SpaceWeather.com also has ephemeris info and a 3-D orbit model: http://www.spaceweather.com/
(This is a little too faint for my telescope (visually) so I hope to follow it on the internet)
If it hits another area, I’d say that there is a technological problem. 😀
Oh, how I dislike what is likely considered scare tactics!
Because it is easy to reject these as failed hypotheses:
If this was the case it should have happened already, and we weren’t here to discuss it.
But there has been 4.5 Gy without total extinction. (Modern detailed model predicts not even LHB managed it.) The likelihood that the remaining 0.5 – 1.5 Gy of biosphere lifetime is cut short is thus minute.
And the then (nearly) independent likelihood that the biosphere goes extinct from any mechanism is too, revealing the biosphere as utterly robust. In sum, these and similar “threats” are revealed as a smaller risk as their real nature.
Now I’m all for mitigating risks, especially since this will be the only 2nd averted environmental damage since the ozone layer protection and AGW prevention seems to end in total FAIL. But then we should mitigate the ROI risks, which means ascertain and mitigate on the level of existing human societies; what would be an unacceptable moral risk that we can practically diminish?
This is then neither here nor there:
So more, again likely considered, scare tactics. Interestingly these risks are, as opposed to social risk, likely very hard to assess. What is “an extinction-level impact”? If it is an impact that causes one species extinction in nature, it wouldn’t harm society or biosphere.
And if it is extrapolated from the only known extinction-causing impact, the Chixculub impactor behind the K-Pg event, it was a rare accident that couldn’t have happened before since the sulfur and calcium containing rocks that were essential to its harm was produced by modern life.
In an interesting parallel, the greatest mass extinction, the Permian-Triassic extinction that killed of more than 90 % of marine species, AFAIU now looks to be a similar rare combination of factors as reported here and here.
The Siberian Traps couldn’t cause the effects all by itself, and really magma and lava penetrations have been a constant during Earth plate tectonic history. But the flood basalt penetrating a massive coal deposit made for global warming and ocean acidification both.
Again this could only happen in modern times due to modern life laying down the (in)appropriate sediments. Besides the irony it tells us that a modern more robust (diversified) biosphere, that potentially can take more harm and survive it, also has remodeled the planet toward being more risk conducive and harmful by producing such enormous waste. These effects (inner robustness vs outer fragility, waste galore) wasn’t an invention of modern human societies!
We should nuke one and see if it has any effect. I mean we got thousands of nuclear weapons laying around you know. It is about time we use it for peaceful purpose.
“And occasionally – once every 10,000 years or so — a really big asteroid (1 km in diameter or larger) comes along and smacks Earth with an extinction-level impact.”
10,000 years! I think you are off here by a factor of at least 10^3. The last extinction-level impact was about 64,000,000 years ago.
@SKPTICTIM
According to Wikipedia (http://en.wikipedia.org/wiki/Impact_event#Sizes_and_frequencies) “asteroids with a 1 km (0.62 mi) diameter strike the Earth every 500,000 years on average”. That would make both of you wrong: you by about 100 times while Nancy only by 50. So Nancy wins! 😉 And I actually read somewhere that the 1 km sized rocks are considered extinction level threats. On the other hand there seems to be a debate going on how much such (and larger) impacts really can be linked to extinctions. Again, see Wikipedia at http://en.wikipedia.org/wiki/Impact_event#Mass_extinctions_and_impacts for reference.
Regards,
/hydrazine
Skeptictim,
There are many minor extinction events since the K-T impact.
Emilio,
Don’t forget there is UN Resolution, A/RES/55/3. Many countries would have to give their consent before a nuke could be launched into space. Also, factors such as velocity and composition would make each object a unique case.
Velocity can be measured in advance. Composition is different. The interceptor rocket needs to have three modules; the impactor, explosive module, and the observer module. First, the impactor hits the asteroid creating dust and providing hard information on its composition and mass distribution of the asteroid. The observer needs to analyze this data and calculate where the explosive module needs to explode to give desired effect. It issue command for the explosive trajectory. And, after the explosion, the observer module needs to measure the effect on asteroid.
Can we getaway with just one impactor? Can we guide the explosive to exact spot and detonate it? Where should the detonation be for the maximum effect? Did the explosion cause desired outcome? If not, what cause the problem? It’s a complex choreographed process done in real time. And we have “zero” hard data point on the subject.
Well said Torbjorn. While even a Chicxlub impact may widespread devastation and cause extinction of any number of species including us it is highly unlikely to sterilise the earth of life. It will merely provide a window of opportunity for new life to fill the gaps as the dinosaurs did following the Permian-Triassic extinction and the mammals during the Palaeocene.