PARIS — The United Nations committee responsible for space affairs in June will send to October’s U.N. General Assembly a resolution calling for an international network of ground-based telescopes to track and analyze potentially dangerous asteroids and other near-Earth objects (NEOs).
The recommendations of the U.N. Committee on the Peaceful Uses of Outer Space, scheduled to meet June 12-21 in Vienna, follow a multiyear study by a group of experts and calls for no new financing by the United Nations.
Instead, the NEO study group recommended coordinating investments already made or under way in ground telescopes and the occasional satellite and sending the NEO data to a central clearinghouse, which would then forward them to national space and civil protection agencies as needed. The study group was chaired by Sergio Camacho, secretary general of the Regional Center for Space Science and Technology Education for Latin America and the Caribbean, which is based in Mexico.
National and regional investment in NEO assessments appears to be accelerating and was certainly given impetus following January’s low-altitude explosion of an untracked and relatively small — 20-meter-diameter — asteroid over Chelyabinsk, Russia.
On May 22, the 20-nation European Space Agency (ESA) inaugurated a NEO Coordination Center at the agency’s facility in Frascati, Italy. An Italian-led consortium has been designing a 1-meter-diameter telescope called FlyEye that, through modular construction, seeks to build a wide-field-of-view instrument to be part of the NEO work.
The 27-nation European Union has provided 5.8 million euros ($7.5 million) in funding for a study of asteroid defense technologies including kinetic impactors, “gravity tractors” and, as a method of last resort, blast deflection by a nuclear device launched to the asteroid to blow it into smaller pieces.
The 3.5-year NEOShield project is managed by the Berlin-based Institute of Planetary Research, which is part of the German Aerospace Center, DLR.
The Canadian space and defense research agencies operate the world’s first satellite dedicated to searching for NEOs from space, NEOSSat, which was launched in February.
Partly funded by NASA, the University of Hawaii’s Institute of Astronomy is building eight small asteroid-detection telescopes to be placed on Hawaiian Island mountaintops, with a scheduled 2015 in-service date.
Other investments are being made that will add to NEO surveillance even if that is not their principal mission. This is the case for the Korea Microlensing Telescope Network; ESA’s Optical Space Telescope in Spain’s Canary Islands, which is used four nights per month to track asteroids; the Arecibo Observatory in Puerto Rico, funded by the U.S. National Science Foundation; and the Goldstone Observatory in California, operated by NASA’s Jet Propulsion Laboratory.
Russia’s Academy of Sciences is building a 1.6-meter telescope that will contribute to NEO assessments. The U.S. Air Force’s Space Surveillance Network of ground radars can track some NEOs even as the network fulfills its main duties of following space debris and orbital objects.
One of the more ambitious efforts under way is the Large Synoptic Survey Telescope, an 8-meter-diameter instrument being built at Cerro Pachon in Chile with private and government funds. The National Science Foundation and the U.S. Energy Department — the telescope will also investigate dark energy — are major backers. Private-sector contributions have come from Microsoft founder Bill Gates and the Charles Simonyi Fund for Arts and Sciences, each of which has contributed more than $10 million.
The telescope is designed to identify asteroids as small as 100 meters in diameter using a 3 billion pixel camera that will scan the night sky and produce some 30 terabytes of data each day. Construction is tentatively scheduled to be finished in time for science operations to start in 2022.
These and other efforts need to be coordinated into a global network to identify threatening asteroids not only by their size and orbit but also by their physical characteristics to determine the likelihood of their breaking up on entering Earth’s atmosphere.
To date, the de facto global clearinghouse for NEO data is the Minor Planet Center in Cambridge, Mass., part of the U.S. Smithsonian Astrophysical Observatory.
Timothy Spahr, director of the Minor Planet Center, told the U.N. meeting in February that the facility is “the world’s center for receiving and distributing asteroid data” and should be key to any U.N. effort to create an International Asteroid Warning Network — one of the proposals of the U.N. expert group.
Spahr said the center maintains a catalog of some 750,000 asteroids, including 10,000 NEOs. He said the facility, equipped with a supercomputer, has the capacity to handle 10 times more data than it currently manages.
Spahr said the greatest need for a global NEO alert system is a network of telescopes to pinpoint “small, imminent impactors” such as the one that created the shockwave over Chelyabinsk.
Thomas Reiter, director for human spaceflight and operations at ESA, agreed. At the inauguration of the agency’s NEO Coordination Center, Reiter said more than 90 percent of the potentially dangerous asteroids of 1 kilometer in diameter or larger have been discovered, but only 10 percent of asteroids 100 meters in diameter or smaller have been cataloged.
Reiter said ESA’s new facility will not be duplicating work done by the Minor Planet Center, but will add ESA’s tracking eyes to the existing capacity. “The more sensors, the higher the likelihood that we can buy time” before a NEO enters the atmosphere, he said.
