Trajectory of 2011 MD from the general direction of the Sun. (Credit: NASA/JPL-Caltech)
Small Asteroid to Whip Past Earth On June 27, 2011
ScienceDaily (June 27, 2011) — Near-Earth asteroid 2011 MD will pass only 12,000 kilometers (7,500 miles) above Earth’s surface on Monday, June 27 at about 9:30 EDT. The asteroid was discovered by the LINEAR near-Earth object discovery team observing from Socorro, New Mexico.
This small asteroid, only 5-20 meters in diameter, is in a very Earth-like orbit about the Sun, but an orbital analysis indicates there is no chance it will actually strike Earth on Monday. If a rocky asteroid the size of 2011 MD were to enter Earth’s atmosphere, it would be expected to burn up high in the atmosphere and cause no damage to Earth’s surface.
A view of the asteroid’s trajectory from the general direction of the Sun indicates that 2011 MD will reach its closest Earth approach point in extreme southern latitudes (in fact over the southern Atlantic Ocean). The incoming trajectory leg passes several thousand kilometers outside the geosynchronous ring of satellites and the outgoing leg passes well inside the ring. One would expect an object of this size to come this close to Earth about every 6 years on average. For a brief time, it may be bright enough to be seen even with a modest-sized telescope.
For more information on 2011 MD and other near-Earth objects, visit http://neo.jpl.nasa.gov.
An asteroid the size of a tour bus will fly past Earth today (June 27) so closely it will be beneath some of the planet’s satellites.
The rock, named asteroid 2011 MD will zoom by just 7,500 miles (12,000 km) above the planet, making a sharp turn forced by Earth’s gravity before winging off into space again. The flyby will occur at about 1 p.m. EDT (1700 GMT).
There is no risk of an impact, NASA scientists said. The space rock, estimated to be between 29 to 98 feet (9 to 30 meters) wide, is likely too small to survive a plunge through our atmosphere anyway. An asteroid this size, if it were mostly stony, would break apart and burn up before hitting the surface. Iron-heavy space rocks are better at surviving the fiery entry, however.
Either way, calculations show that asteroid 2011 MD will make a dogleg shift in its trajectory and scoot on by.
“There is no chance that 2011 MD will hit Earth but scientists will use the close pass as opportunity to study it w/ radar observations,” astronomers with NASA’s Asteroid Watch program at JPL said. [Photos: Asteroids in Deep Space]
At closest approach, the asteroid will be above the coast of Antarctica. It will be well below geosynchronous satellites, which orbit 22,236 miles (35,786 km) above Earth. Experts say there is little chance the rock will hit a satellite, simply because of the vast expanse and relatively small number of satellites.
The asteroid will remain well above the orbit of the International Space Station, which flies about 220 miles (354 km) above Earth.
Objects the size of 2011 MD usually make close Earth passes like today’s event every six years or so, NASA estimates. However, not all of them are discovered. This rock was discovered June 22. The closest recorded space rock pass was made by asteroid 2011 CQ1, which came within 3,400 miles (5,471 kilometers) of Earth on Feb. 4 of this year.
Asteroid 2011 MD will be likely visible in medium-sized telescopes by experienced observers who are able to find and track a moving object. Even NASA doesn’t expect to see much, however.
“We won’t likely be releasing photos of the object since they would only be points of light,” Don Yeomans, of NASA’s Near-Earth Object Program Office at NASA’s Jet Propulsion Laboratory, told SPACE.com. “Radar astronomers will attempt observations but 2011 MD is so small that even if successful, there are not likely to be any noteworthy images released.”
Will be nearer Islanders, Brit garrison than Japan is
An asteroid the size of a bus and massing 600 tonnes is barrelling through space toward planet Earth at terrific speed as this report is written. Astronomers say there is no chance that the object, dubbed 2011 MD, will strike our planet but it will corner sharply through our gravitational field and descend to just 7,600 miles above the surface.
Thus, if you were standing beneath 2011 MD‘s point of closest approach the speeding asteroid would be closer to you than the other side of the planet is: closer than Australia is to someone in London, for instance*.
In fact, as 2011 MD is expected to reach its lowest point this evening above the South Atlantic, only residents of the Falkland Islands and passing mariners will be beneath it (and it will be nearer to them than Japan is, as well as being much nearer than communications and TV satellites in geostationary orbit).
According to NASA the hurtling space boulder is “5-20” metres across and masses something on the order of 630 tonnes. If it were to strike Earth – which it won’t – it would release energy equivalent to a measly 10,000 tonnes of TNT exploding. Even this would be entirely within the upper atmosphere: 2011MD isn’t big enough to avoid burning up on its way down, there would be no surface impact.
“One would expect an object of this size to come this close to Earth about every 6 years on average,” comment the astronomers of NASA’s Near Earth Object Program Office. ®
*For our non-British readers, simply substitute the relevant Antipodean region as may apply to you.