Posted on by Nancy Atkinson

Asteroid or Space Junk? Object Makes Close Pass by Earth Wednesday

Asteroid or rocket booster? 2010 AL30 as imaged remotely from Australia on Jan. 11, 2010. Credit: Ernesto Guido & Giovanni Sostero

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Caption: Asteroid or rocket booster? 2010 AL30 as imaged remotely from Australia on Jan. 11, 2010. Credit: Ernesto Guido & Giovanni Sostero, Remanzacco Observatory.

An unusual object will make a close flyby of Earth on Wednesday, coming within only 128,000 km (about 80,000 miles), or at a distance about three times less than the moon’s orbit. The object, named 2010 AL30, is about 10-15 meters long, and asteroid watchers say there is no chance it will hit the planet. But is it an asteroid or perhaps a piece of space junk, like a spent rocket booster?

UPDATE: The Solar System Dynamics website now says the object is an Apollo-type asteroid, which are Near-Earth asteroids that have orbits which cross the Earth’s orbit and pass approximately 1 AU or less from Earth.

According to Italian astronomers Ernesto Guido and Giovanni Sostero of the Remanzacco Observatory, who took this image (above) of 2010 AL30, it has an orbital period of almost exactly one year and might be a man-made object.

However, Alan Harris, senior researcher at the Space Science Institute said the object has a perfectly ordinary Earth-crossing orbit.

“Unlikely to be artificial, its orbit doesn’t resemble any useful spacecraft trajectory, and its encounter velocity with Earth is not unusually low,” he said.

The object make its closest approach at 12:48 GMT on Wednesday, and and amateur astronomers are encouraged to observe 2010 AL30 as a 14th magnitude star in the constellations of Orion, Taurus, and Pisces. Check here to get the ephemeris of the object from the Solar System Dynamics website.

Several observatories, including the Goldstone Radar will be observing NEO 2010 AL30 during its Earth flyby. After the January 13 close flyby, it will go too close to the Sun to be observed.

Sources: Remanzacco Observatory, Spaceweather.com

Posted on by Nancy Atkinson

Space Junk Threatens Future Missions

Low Earth Orbit
Estimated number of objects in low Earth orbit. Credit: NASA

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The U.S. Air Force began upgrading its ability to predict possible collisions in space after two satellites collided in February 2009, and has now done a collision analysis on over 800 maneuverable satellites. They hope to be able to track 500 more non-maneuvering satellites by year’s end. But maneuverable satellites aren’t the problem. The amount of space debris has risen by 40 per cent in the past four years alone. The Air Force Space Command now tracks 21,000 orbiting objects that are 10 centimeters or more across – including the 800 working satellites – and estimates that there are 500,000 smaller fragments in orbit.

“Our goal now is to do that conjunction assessment for all active satellites, roughly around 1,300 satellites, by the end of the year and provide that information to users as required,” said Lieutenant General Larry James, U.S. Strategic Command’s Joint Functional Component Command for Space, speaking at the Strategic Space Symposium this week in Omaha, Nebraska.

Some of the 500 satellites still to be assessed cannot be maneuvered in orbit because they are not functioning, or do not carry extra fuel that would be needed to move them once in orbit.

At another conference this week, the European Air and Space Conference in Manchester, UK, Hugh Lewis of the University of Southampton estimated the number of close encounters between objects in orbit will rise 50% in the next decade, and quadruple by 2059. The number of pieces of space debris has risen by 40% in the past four years alone.

Countermeasures by satellite builders and operators to avoid additional space debris are encouraged, but they add to the cost of missions.

Lewis has determined that compared with the 13,000 close approaches per week now, he projects there will be 20,000 a week in 2019 and upwards of 50,000 a week in 2059. From this he predicts that satellite operators will have to make five times as many collision avoidance maneuvers in 2059 as they will in 2019. “There’s going to be a big impact,” says Lewis. “You’re going to need more tracking to remove uncertainty about close approaches and undertake more maneuvers.”

Sources: Reuters, New Scientist