With some good telescope and much luck it will be possible to spot it from some areas.
Asteroid 2011 MD was discovered Wednesday (June 22) by LINEAR, a pair of robotic telescopes in New Mexico that scan the skies for near-Earth asteroids. The best estimates suggest that this asteroid is between 29 to 98 feet (9 to 30 meters) wide.
According to NASA's Near-Earth Object Office at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., an object of this size can be expected to come this close to Earth about every 6 years or so, on average. [Photo of asteroid 2011MD trajectory]
"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 wrote in a Twitter post Thursday (June 23).
Even if the asteroid were to enter Earth's atmosphere, it likely wouldn't reach the surface, they added.
"Asteroid 2011 MD measures about 10 meters. Stony asteroids less than 25 m would break up in Earth's atmosphere & not cause ground damage," Asteroid Watch scientists said.
The asteroid's upcoming Earth flyby will be a close shave, but not a record for nearby passing asteroids. The record is currently held by the asteroid 2011 CQ1, which came within 3,400 miles (5,471 kilometers) of Earth on Feb. 4 of this year.
For several hours prior to its closest approach, 2011 MD will be visible in moderately-large amateur telescopes. But despite its close approach, actually seeing this asteroid will not be an easy task.
"These objects are so small (10 meters) that normally a sizeable telescope is required," Asteroid Watch scientists warned.
You will need to have access to an excellent star atlas, and because it will be moving so rapidly you'll also need the very latest data from the Minor Planet Center to track its precise course against the background stars. The asteroid is not expected to get very bright; about 250 times dimmer than the faintest stars visible to the eye without optical aid. [Photos: Asteroids in Deep Space]
The asteroid will pass so close that Earth's gravity will sharply alter the asteroid's trajectory.
After making its closest pass to Earth, the asteroid will zoom through the zone of geosynchronous satellites. The chance of a collision with a satellite or piece of space junk is exceedingly remote.
http://www.space.com/12067-asteroid-...y-june-27.html
Trajectory of asteroid 2011 MD on June 27, 2011 projected onto the Earth's orbital plane. Note from this viewing angle, the asteroid passes underneath the Earth.
CREDIT: NASA UPDATE for 5:35 p.m. ET: NASA has recalculated the time of closest approach for this event to be about 3 1/2 hours later than initially reported.