We can hope that the celestial events of February 15, including the spectacular fireball over Chelyabinsk and the near-miss from asteroid 2012 DA14, have raised public consciousness about Earth’s neighbors in space. And indeed, this seems to be the case. Media outlets were flooded with articles, photos and video, and talk show hosts found themselves asking what could be done to prevent future impacts. Could all of this prompt a new surge of interest in space?
The scenario is exactly what Arthur C. Clarke wrote about in Rendezvous with Rama (1972), where what it takes for humanity to get serious about developing a protective system (and, by extension, about pushing its space program forward) is an impact. We can be grateful that the one we’ve just seen was far smaller than Clarke’s, as described in the first chapter of the novel:
At 0946 GMT on the morning of September 11 in the exceptionally beautiful summer of the year 2077, most of the inhabitants of Europe saw a dazzling fireball appear in the eastern sky. Within seconds it was brighter than the Sun, and as it moved across the heavens — at first in utter silence — it left behind it a churning column of dust and smoke.
Somewhere above Austria it began to disintegrate, producing a series of concussions so violent that more than a million people had their hearing permanently damaged. They were the lucky ones.
Clarke goes on to recount the impact in northern Italy, where Padua, Verona and Venice are destroyed by the combination of impact and tsunami. The deaths of 600,000 people and the great chunk torn out of human history create a resolution that this must not happen again, and out of this is born the system of radars that eventually finds the alien intruder dubbed Rama. Clarke’s book is about the encounter with this enigmatic vessel, but the asteroid-warning radars he imagines create the kind of warning grid we may eventually put in place.
The B612 Foundation has been making the case for asteroid detection and mitigation studies for some years now. Its Sentinel Space Telescope is scheduled for launch in 2018, with the aim of detecting over 90 percent of asteroids over 100 meters in diameter — these are the ones large enough to destroy an entire region of the planet if they were to hit us. Sentinel also aims to track more than 50 percent of near-Earth asteroids in the DA-14 category. With decades of warning, says CEO Ed Lu in this B612 news release, we can use existing technology to destroy or alter the trajectory of any such objects.
Chelyabinsk and 2012 DA14 also put the University of Hawaii at Manoa’s work on ATLAS into the news. The Asteroid Terrestrial-Impact Last Alert System — an ominous title, that — is to operate eight telescopes, each with a camera of up to 100 megapixels, on sites in the Hawaiian Islands. The goal here is to offer, according to this news release from the university’s Institute for Astronomy in Honolulu, a one-week warning for a 45-meter asteroid and a three-week warning for a 140-meter object. That’s enough time, according to astronomer John Tonry, “to evacuate the area of people, take measures to protect buildings and other infrastructure, and be alert to a tsunami danger generated by ocean impacts.”
But among the spate of asteroid warning news items that surged over the weekend, the project that caught my eye first was one called DE-STAR, the explanation of whose acronym is so tortuous that I will direct you to the University of California at Santa Barbara news release it appeared in. What UC-Santa Barbara researchers Philip Lubin and Gary Hughes are proposing is a system that could, over the course of a year, destroy asteroids ten times larger than 2012 DA14, using a massive phased array of lasers to break up or evaporate the object.
“This system is not some far-out idea from Star Trek. All the components of this system pretty much exist today. Maybe not quite at the scale that we’d need –– scaling up would be the challenge –– but the basic elements are all there and ready to go. We just need to put them into a larger system to be effective, and once the system is there, it can do so many things.”
DE-STAR is being described as a ‘directed energy orbital defense system,’ one that uses solar energy to feed its lasers. The researchers have calculated DE-STAR systems in various configurations, including a 100-meter DE-STAR 2 and a 10-kilometer DE-STAR 4, the latter capable of delivering the energy needed to obliterate a 500-meter asteroid in about a year.
Image: Concept drawing of the DE-STAR system engaging both an asteroid for evaporation or composition analysis, and simultaneously propelling an interplanetary spacecraft. Courtesy Philip M. Lubin.
And now we start getting into Bob Forward territory as Lubin and Hughes go on to describe a DE-STAR 6 that would function not only in asteroid defense but as the propulsion system of an interstellar spacecraft, beaming enough laser energy to the craft to get it up to a substantial percentage of the speed of light. An asteroid mitigation strategy that involved planetary safety, power generation and spacecraft propulsion is a tempting long-term goal, but a DE-STAR 2 about the size of the International Space Station could begin small-scale trajectory alterations on a variety of objects as we experiment with planet-defending techniques.
Meanwhile, many of us talked to Claudio Maccone at the Huntsville conference and learned of his plans to attend the IAA’s Planetary Defense Conference, coming up in Flagstaff on April 15-19. Claudio crosses the ocean all the time, as inveterate a conference-goer as I’ve ever seen, but who would have thought this year’s Planetary Defense meeting would become so highly visible? You can bet media coverage at Flagstaff will be considerably higher than in years past thanks to Chelyabinsk and 2012 DA14, making them unusually effective wake-up calls for our species.