Ten Thousandth Near-Earth Object Discovered   
       
   June 25, 2013:  More than 10,000 asteroids and comets that can pass near Earth   
   have now been discovered. The 10,000th near-Earth object, asteroid 2013 MZ5,   
   was first detected on the night of June 18, 2013, by the Pan-STARRS-1   
   telescope, located on the summit of the Haleakala crater on Maui. Managed by   
   the University of Hawaii, the PanSTARRS survey receives NASA funding.   
       
   "Finding 10,000 near-Earth objects is a significant milestone," said Lindley   
   Johnson, program executive for NASA's Near-Earth Object Observations (NEOO)   
   Program at NASA Headquarters. "But there are at least 10 times that many more   
   to be found before we can be assured we will have found any and all that could   
   impact and do significant harm to the citizens of Earth."   
       
   http://www.jpl.nasa.gov/images/asteroid/20130624/neo20130624-full.gif   
       
   Asteroid 2013 MZ5 as seen by the University of Hawaii's PanSTARR-1 telescope.   
   In this animated gif, the asteroid moves relative to a fixed background of   
   stars. Image credit: PS-1/UH | Unannotated version   
   Near-Earth objects (NEOs) are asteroids and comets that can approach the   
   Earth's orbital distance to within about 28 million miles (45 million   
   kilometers). They range in size from as small as a few feet to as large as 25   
   miles (41 kilometers) for the largest near-Earth asteroid, 1036 Ganymed.   
   Ninety-eight percent of all known near-Earth objects were first detected by   
   NASA-supported surveys: statistics   
       
   Asteroid 2013 MZ5 is approximately 1,000 feet (300 meters) across. Its orbit   
   is well understood and will not approach close enough to Earth to be   
   considered potentially hazardous.   
       
   "The first near-Earth object was discovered in 1898," said Don Yeomans,   
   long-time manager of NASA's Near-Earth Object Program Office at the Jet   
   Propulsion Laboratory in Pasadena, Calif. "Over the next hundred years, only   
   about 500 had been found. But then, with the advent of NASA's NEO Observations   
   program in 1998, we've been racking them up ever since. And with new, more   
   capable systems coming on line, we are learning even more about where the NEOs   
   are currently in our solar system, and where they will be in the future."   
       
   Of the 10,000 discoveries, roughly 10 percent are larger than six-tenths of a   
   mile (one kilometer) in size - roughly the size that could produce global   
   consequences should one impact the Earth. However, the NASA NEOO program has   
   found that none of these larger NEOs currently pose an impact threat and   
   probably only a few dozen more of these large NEOs remain undiscovered.   
       
   The vast majority of NEOs are smaller than one kilometer, with the number of   
   objects of a particular size increasing as their sizes decrease. For example,   
   there are expected to be about 15,000 NEOs that are about one-and-half   
   football fields in size (460 feet, or 140 meters), and more than a million   
   that are about one-third a football field in size (100 feet, or 30 meters). A   
   NEO hitting Earth would need to be about 100 feet (30 meters) or larger to   
   cause significant devastation in populated areas. Almost 30 percent of the   
   460-foot-sized NEOs have been found, but less than 1 percent of the   
   100-foot-sized NEOs have been detected.   
       
   http://tinyurl.com/oo3flgp   
       
   Click to view an interactive orbit of near-Earth asteroid 2013 MZ5. When it   
   originated, the NASA-instituted Near-Earth Object Observations Program   
   provided support to search programs run by the Massachusetts Institute of   
   Technology's Lincoln Laboratory (LINEAR); the Jet Propulsion Laboratory   
   (NEAT); the University of Arizona (Spacewatch, and later Catalina Sky Survey)   
   and the Lowell Observatory (LONEOS). All these search teams report their   
   observations to the Minor Planet Center, the central node where all   
   observations from observatories worldwide are correlated with objects, and   
   they are given unique designations and their orbits are calculated.   
       
   "When I began surveying for asteroids and comets in 1992, a near-Earth object   
   discovery was a rare event," said Tim Spahr, director of the Minor Planet   
   Center. "These days we average three NEO discoveries a day, and each month the   
   Minor Planet Center receives hundreds of thousands of observations on   
   asteroids, including those in the main-belt. The work done by the NASA   
   surveys, and the other international professional and amateur astronomers, to   
   discover and track NEOs is really remarkable."   
       
   Within a dozen years, the program achieved its goal of discovering 90 percent   
   of near-Earth objects larger than 3,300 feet (1 kilometer) in size. In   
   December 2005, NASA was directed by Congress to extend the search to find and   
   catalog 90 percent of the NEOs larger than 500 feet (140 meters) in size. When   
   this goal is achieved, the risk of an unwarned future Earth impact will be   
   reduced to a level of only one percent when compared to pre-survey risk   
   levels. This reduces the risk to human populations, because once an NEO threat   
   is known well in advance, the object could be deflected with current space   
   technologies.   
       
   Currently, the major NEO discovery teams are the Catalina Sky Survey, the   
   University of Hawaii's Pan-STARRS survey and the LINEAR survey. The current   
   discovery rate of NEOs is about 1,000 per year. .   
       
   Credits:   
       
   Production editor: Dr. Tony Phillips | Credit: Science@NASA   
       
   More information:   
       
   NASA's Near-Earth Object Observations Program manages and funds the search   
   for, study of and monitoring of asteroids and comets whose orbits periodically   
   bring them close to Earth. The Minor Planet Center is funded by NASA and   
   hosted by the Smithsonian Astrophysical Observatory in Cambridge, MA. JPL   
   manages the Near-Earth Object Program Office for NASA's Science Mission   
   Directorate in Washington. JPL is a division of the California Institute of   
   Technology in Pasadena. More information about asteroids and near-Earth   
   objects is available at: http://neo.jpl.nasa.gov/, http://www.jp   
   .nasa.gov/asteroidwatch and via Twitter at http://www.twitter.co   
   /asteroidwatch .   
       
       
   Regards,   
       
   Roger   
      
   --- D'Bridge 3.94   
    * Origin: NCS BBS - Houma, LoUiSiAna (1:3828/7)