Asteroids Aff

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NASA has unique asteroid expertise and ongoing research

MURRILL AND WHALEN 1998 (Mary Beth Murrill and Mark Whalen, NASA, “JPL will establish Near-Earth Object Program Office for NASA,” July 24,

"We determined that in order to achieve our goals we need a more formal focusing of our near-Earth object tracking efforts and related communications with the supporting research community," said Dr. Carl Pilcher, science director for Solar System Exploration in NASA's Office of Space Science, NASA Headquarters. "I want to emphasize that science research solicitations and resulting peer reviews, international coordination, and strategic planning regarding future missions will remain the responsibility of NASA Headquarters." In addition to managing the detection and cataloging of near-Earth objects, the new NASA office will be responsible for facilitating communications between the astronomical community and the public should any potentially hazardous objects be discovered as a result of the program, Pilcher said. JPL was selected to host the program office because of its expertise in precision tracking of the positions and predicted paths of asteroids and comets. No significant additional staff hiring at JPL is expected at this time. "There is some extraordinary research being done on near-Earth objects and much of it is ongoing here at JPL," Yeomans said.

NASA is empirically successful

NATIONAL RESEARCH COUNCIL 2010 – Research Council Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategiesand Space Studies Board Aeronautics and Space Engineering Board Division on Engineering and Physical Sciences (“Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies”,

The LINEAR program at the Massachusetts Institute of Technology Lincoln Laboratory is funded by the U.S. Air Force and NASA and was the most successful NEO search program from 1997 until 2004. The goal of LINEAR is to demonstrate the application of technology originally developed for the surveillance of Earth-orbiting satellites to the discovering and cataloguing of NEOs. LINEAR consists of a pair of GEODSS telescopes at the Lincoln Laboratory's Experimental Test Site at White Sands Missile Range in Socorro. New Mexico. These two I -meter-diameter telescopes were eventually joined by a third telescope used for the confirmation of NEO orbits and were able to detect asteroids as faint as M = 20. LINEAR has discovered 2.210 NEOs and accounted for more than 50 percent of all NEO discoveries from 1998 to 2004. In 2005. the rate of discoveries by the Catalina Sky Survey increased substantially and overtook that of LINEAR.


Increased NEO detection efforts would dramatically increase the rate of discovery

Ames Research Center 2003 - NASA’s Ames Research Center is a world-class research facility located in the heart of Silicon Valley. The center is involved with many high-tech projects, ranging from developing small spacecraft to managing some of the world’s largest supercomputers, and conducting astrobiology research (July 8, * Dr. Harrison H. Schmitt * Dr. Carolyn S. Shoemaker * David H. Levy * Dr. John Lewis * Dr. Neil D. Tyson * Dr. Freeman Dyson * Dr. Richard P. Hallion * Dr. Thomas D. Jones * Bruce Joel Rubin * Dr. Lucy Ann McFadden * Erik C. Jones * Marc Schlather * William E. Burrows, “ NASA NEO News: Open Letter to Congress on Near Earth Objects ” )

The United States is currently engaged in a search for all NEOs greater than 0.62 miles (a kilometer) in diameter. The effort is producing results, but only a few dozen researchers are funded to conduct this basic survey. Resources committed to this work have been very modest and not commensurate with the potential threat; thus, additional investment in search programs is both appropriate and prudent. A dramatic improvement in the rate at which asteroids and comets are discovered would likely result if the United States were to increase the current level of funding, now at about $3.5 million per year, to at least $20 million annually.


Space-based detection combined with ground assets is critical to detect potential collisions

NAC 2010 (“Report of the NASA Advisory Council Ad Hoc Task Force on Planetary Defense,” Oct 6,

8. To achieve the NEO search goals in a timely manner as directed by the 2005 George E. Brown NEO Survey legislation, the nation will likely require acquisition and operation of a space-based survey element in addition to ground-based systems. A spacecraft operating with sensors in the infrared band from an orbit sunward of Earth’s (e.g., a Venus-like orbit) offers great advantages in rapid search and repeat observation frequency. 9. When used in conjunction with ground-based optical observations, radar data can dramatically improve orbit knowledge of recently discovered NEOs. However, radars have limited sky coverage and can observe NEOs only at relatively close range. A modest-aperture, space-based infrared telescope with its advantageous orbital geometry (an observing location and direction different than Earth’s) could enable a much larger total of positional observations over much longer orbital tracks. Such tracking from 8 multiple solar system vantage points (e.g. Earth and a Venus-like orbit) will aid in quickly reducing orbit uncertainties when radar follow-up is unavailable. 10. While the search for the NEO population larger than 140 meters is underway and the necessary orbit precision is being obtained, there will be a transition period or window of perceived vulnerability, lasting at least two decades. Some NEOs will present worrisome probabilities of impact, and sufficient orbit precision to rule out an impact may not be obtained before a decision must be made to launch a deflection campaign. The more rapid search enabled by a space-based system will, by aiding early ground-based followup, shorten this window of vulnerability by several years. Impact threats will still appear as the catalog nears completion, but continuing observations will reduce uncertainty and increase warning time.

Space based telescopes are key to detecting darker asteroids – infrared capability

NATIONAL RESEARCH COUNCIL 2010 - Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies Space Studies Board (“ Survey and Detection of Near-Earth Objects ” pg. 33, Aeronautics and Space Engineering Board Division on Engineering and Physical Sciences,

Asteroids in orbits that bring them close to Earth are especially menacing if they are dark and have evaded detection by ground-based surveys in visible light. Also, since the assumed albedo might not be representative of a dark object, the calculated diameter could be misrepresented as smaller than the object’s true diameter. But dark objects are especially detectable in infrared light. The bias against lower-albedo (darker) asteroids is reduced through the use of infrared observations in space: At the temperatures and albedos that dominate the solar system inside the orbit of Mars, the diameters computed from infrared signals are more accurate than those derived from visible-light reflections from asteroids and comets. Thus, the detections of potentially hazardous NEOs by an infrared telescope (one sensitive to infrared light) will result in a more accurate size-frequency distribution for these objects. Additionally, the background from other astronomical sources is about 100 times lower at infrared wavelengths of 10 microns (a micron is one-millionth of a meter) than at visible wavelengths, since most stars emit far less infrared light than visible light. This difference reduces the chance for interference from other strong astronomical sources. Combined with visible-light data, the albedos of NEOs detected in the infrared can also be derived. This derivation of albedos offers insight into composition and surface properties. The Wide-field Infra-red Survey Explorer for Near-Earth Objects (NEOWISE), a U.S. mission (see below), will leverage this infrared advantage.

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