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The airblast from the Chelyabinsk meteor is estimated at 300-500 kilotons. That’s equivalent to the yield of two or three Minuteman missile warheads. Fortunately, the blast occurred at high altitude (10-15 miles above the ground). If the meteor had been a bit stronger (more iron and less rock), it would have held together a a bit longer. The blast would have been lower, casualties and destruction much more severe.

One disturbing aspect of this event is the fact that Russia large military installations near Chelyabinsk. A large meteor impact near a military base could potentially be mistaken for a nuclear first strike, setting off a chain reaction.

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A cosmic catastrophe may have occurred in our part of the galaxy less than 1300 years ago. A similar event today could have damaging effects on our technological civilization.

A new paper by astronomers Valeri Hambaryan and Ralph Neuhӓuser at the University of Jena, Germany suggests that a short-duration gamma-ray burst from the merging of two stellar remnants may have caused an intense blast of high-energy radiation that hit the Earth in the 8th century. The paper, A Galactic short gamma-ray burst as cause for the 14C peak in AD 774/5, is published in the Monthly Notices of the Royal Astronomical Society.

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The European Space Agency is seeking research ideas to help guide development of a joint US-European asteroid deflection mission now under study.

The Asteroid Impact and Deflection Assessment (AIDA) mission would consist of two space probes, which would be launched toward a binary asteroid.

The Double Asteroid Redirection Test, or DART, would collide with the smaller of the two asteroids, while the Asteroid Impact Monitor (AIM) surveys the asteroids in detail, before and after the collision. DART is being designed by the Johns Hopkins Advanced Physics Laboratory in the US, with support from NASA Goddard Space Flight Center, Johnson Space Center, and JPL. AIM is being designed by ESA.

The DART mission would also include ground-based observations to measure the deflection independently of AIM. This ensures that the DART impact would return return useful data even if AIM failed. Working together, the two probes would return data on momentum transfer and characteristics of the resulting crater.

ESA is seeking concepts for ground- and space-based investigations to improve understanding of high-speed collisions between man-made and natural objects in space.

The AIDA design study is a successor to the Don Quijote study, which ESA completed in July 2005. Like AIDA, Don Quijote involved two probes: an orbiter called Sancho and an impactor called Hidalgo. Sancho would arrive at the asteroid several months prior to Hidalgo to accurately measure the body’s position, shape, mass, and gravity field.

Don Quijote differed from AIDA in planning to target a single asteroid, of about 500 meters diameter, rather than a binary asteroid. Construction of the Don Quixote probes could have begun in 2006, if the project had been approved. Unfortunately, that did not happen. We hope AIDA will have better luck.

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This rogues gallery shows the relative size of the asteroids and comets that have been visited by unmanned space probes, courtesy of Emily Lakdawalla of the Planetary Society.

We look forward to the day when we can show a similar picture of all asteroids visited by manned spacecraft.

That seems like a tall order, but remember — none of unmanned missions existed just a few years ago.

We can rebuild the space program. We have the technology. Johnson Space Center has done advanced concept studies of a deep space ship, Nautilus X, that could be built within the agency’s current budget. Instead, NASA spends its money on the politically mandated Space Launch System and Orion capsule, which duplicate capabilities already available (or soon to be available) from companies like SpaceX and United Launch Alliance.

Why should we be interested in the asteroids, when there are more alluring destinations like Mars? Well, it wasn’t Mars that killed the dinosaurs. We’re reminded of a (possibly apocryphal) quote from Leon Trotsky: “You may not be interested in war, comrade, but war is interested in you!”

A cool video from the Near Earth Object Program Office at NASA’s Jet Propulsion Laboratory.

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Unfortunately, the deflection technology, which they mention at the end, is not even in development. Protecting the Earth’s population from a possible global extinction event is not a goal whose value penetrates to politicians and wonks in DC.

Washington’s blindness to the asteroid threat can be seen in a recent report by the National Academy of Sciences, NASA’s Strategic Direction and the Need for a National Consensus. The report dismisses the value of NASA’s proposed asteroid mission with the following statement:

The committee has seen little evidence that a current stated goal for NASA’s human spaceflight program — namely, to visit an asteroid by 2015 — has been widely accepted as a compelling destination by NASA’s own workforce, by the nation as a whole, or by the international community. Although asteroids remain important subjects for both US and international robotic exploration and study, on the international front, there appears to be continued enthusiasm for a mission to the Moon but not for an asteroid mission.

This statement is deeply flawed. NASA works for the American people, not its own workforce or the international community — and if the committee saw little evidence that the Americans find asteroids compelling, it simply wasn’t looking. Bookstores, documentaries, and Hollywood movies attest to widespread public interest in the asteroid-impact hazard.

Obviously, the NAS committee failed to make the connection between NASA’s manned asteroid mission and planetary defense. The committee implicitly assumes that asteroids are merely subjects of scientific study rather than natural hazards of potential resources. That is a common failing in the scientific community — and one reason why the NAS is the wrong organization to ask for recommendations on space policy. Of course, President Obama and NASA Administrator Major General Charles Bolden have failed to publicly make the connection as well. There is plenty of blame to go around here.

It is becoming increasingly obvious that the future of human spaceflight — and perhaps the future of the human race — will depend on people outside of Washington, DC.