Subscribe to our free daily newsletters
. 24/7 Space News .




Subscribe to our free daily newsletters



Corkscrew Asteroid About To Leave The Local Earth Neighborhood

The typical corkscrew path of an Earth Coorbital Asteroid (pictured). Earth's temporary moon 2003 YN107 has come - and is going. Image credit: NASA
by Tony Phillips
Science at NASA
Huntsville AL (SPX) Jun 12, 2006
News flash: Earth has a "second moon." Asteroid 2003 YN107 is looping around our planet once a year. Measuring only 20 meters across, the asteroid is too small to see with the unaided eye - but it is there.

This news, believe it or not, is seven years old.

"2003 YN107 arrived in 1999," said Paul Chodas of NASA's Near Earth Object Program at Jet Propulsion Laboratory in Pasadena, Calif., "and it's been corkscrewing around Earth ever since." Because the asteroid is so small and poses no threat, it has attracted little public attention, but he and other experts have been monitoring it.

"It's a very curious object," Chodas said.

Most near-Earth asteroids, when they approach Earth, simply fly by. They come and they go, occasionally making news around the date of closest approach. 2003 YN107 is different: It came and it stayed.

"We believe 2003 YN107 is one of a whole population of near-Earth asteroids that don't just fly by Earth," Chodas said. "They pause and corkscrew in our vicinity for years before moving along."

These asteroids are called Earth Coorbital Asteroids or "co-orbitals" for short. Essentially, they share Earth's orbit, going around the Sun in almost exactly one year. Occasionally a co-orbital catches up to Earth from behind, or vice versa, and the dance begins: The asteroid, while still orbiting the sun, slowly corkscrews around our planet.

"These asteroids are not truly captured by Earth's gravity," Chodas said, "but from our point of view, it looks like we have a new moon."

Astronomers know of at least four small asteroids that can do this trick: 2003 YN107, 2002 AA29, 2004 GU9 and 2001 GO2. "There may be more," Chodas said. He said he thinks the list will grow as asteroid surveys improve in sky coverage and sensitivity.

At the moment, only two co-orbitals are actually nearby: 2003 YN107 and 2004 GU9. The others are scattered around Earth's orbit.

2004 GU9 is perhaps the most interesting. It measures about 200 meters across, relatively large. And according to calculations just published in the Monthly Notices of the Royal Astronomical Society (S. Mikkola et al., 2006) it has been looping around Earth for 500 years - and may continue looping for another 500. It's in a remarkably stable "orbit."

Right now, however, researchers are paying more attention to 2003 YN107 for one simple reason: it's about to depart. The asteroid's corkscrew path is lopsided and on June 10th it will dip within 3.4 million kilometers ((2.1 million miles) from Earth, slightly closer than usual. Earth's gravity will then give the asteroid the nudge it needs to leave.

"This is a chance to observe one of these asteroids (on the way out)," Chodas explained.

It won't be gone forever, however. In about 60 years, 2003 YN107 will lap Earth again, resuming its role as a temporary, corkscrewing moonlet. In due course, other co-orbitals will do the same.

Each encounter is an opportunity for study - and possibly profit. Even the most powerful telescopes cannot see much of these tiny asteroids; they're just specks in the eyepiece. But one day, when the space program is more advanced, it might be possible to visit, explore the moonlets and tap their resources.

"For now, they're just a curiosity," Chodas said.

Related Links
Science at NASA



Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News


Asteroid Provides Pristine Record Of Solar Systems History
Ann Arbor MH (SPX) Jun 02, 2006
A small, near-Earth asteroid named Itokawa is just a pile of floating rubble, probably created from the breakup of an ancient planet, according to a University of Michigan researcher was part of the Japanese space mission Hayabusa.







  • NASA Ames Lays Out CEV Tasks
  • One For The Record Books Malaysian Heads Into Space
  • TPS Enables Study Of Mysterious Pioneer Anomaly
  • Griffin Welcomes Russian Help In Future Space Missions

  • Opportunity On The Road Again
  • Stationary Spirit Progressing On Long-Term Experiments
  • An Ancient Martian Caldera In Apollinaris Patera
  • Aeroflex Awarded Mars Science Lab Contracts

  • Sea Launch To Orbit Telecom Satellite June 17
  • NASA Picks Atlas V To Launch Mars Science Laboratory Mission
  • Sea Launch Prepares For Galaxy 16 Liftoff
  • SES Global Contracts Sea Launch For AMC-21 Satellite

  • EarthData Wins 16 Million Contract To Map Papua New Guinea
  • Global Ecology Inks Partnership With Japanese Satellite Firm
  • First CloudSat Images Wowing Scientists
  • UAE To Monitor Construction Sites Via Satellite

  • New Horizons Crosses The Asteroid Belt
  • Trio Of Neptunes And Their Belt
  • New Model Could Explain Eccentric Triton Orbit
  • New Horizons Taking Exploration To Edge Of Sol

  • Astronomers Find Ancient Cities Of Galaxies
  • Scientists Can Predict Pulsar Starquakes
  • Quark Stars Could Produce Biggest Bang
  • Nearby Extreme Galaxies Linked To Humble Roots

  • The Sky Is Falling
  • SMART-1 Captures Central Peaks Of Zucchius Crater
  • Lunar Highlands And Mare Landscapes
  • Scientist Dreams Of Us Revisiting The Moon

  • Saft To Supply Li-ion Batteries For Galileo Satellites
  • GPS Phones To Streamline And Add Content
  • Lockheed Martin And EADS To Cooperate On Satellite Navigation Standards
  • QinetiQ Joins Galileo Development

  • The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement