According to Space.com, current estimates show that Asteroid 2014 HQ124, was detected in April by Nasa's Wise telescope.
While it is not unusual for asteroids to fly past Earth, or just outside the orbit of the moon, it is less common to discover a previously unknown celestial object of that size. According to Nasa, the Minor Planet Center has classified 2014 HQ124 as a "Potentially Hazardous Asteroid".
The asteroid is inclined to the plane of the solar system by 26 degrees and is currently at -71 degrees inclination. It is out of reach of all but most southern telescopes.
On 6 June 2014 the asteroid will brighten to about apparent magnitude 13.7 and be in Horologium, a small and faint constellation in the southern sky.
Near the closest approach to Earth on 8 June, the asteroid will cross the celestial equator to become a northern hemisphere object but will have an elongation of about 20 degrees from the Sun.
The asteroid could be visually lost in astronomical twilight during the closest approach to Earth, but it will be visible online. It will be broadcast online via the Slooh Space Camera and the Goldstone Deep Space Network.
The meteorite was discovered by Nasa's Wide Field Infrared Survey, an infrared-wavelength astronomical space telescope launched in December 2009.
It was placed in hibernation in February 2011 when its transmitter turned off, and it discovered the first Y Dwarf and Earth trojan asteroid, as well as tens of thousands of new meteors and numerous star clusters.
Earlier this week, asteroid 2014 KH39 silently zipped past Earth at a distance of 272,460 miles (438,480 km) or 1.14 lunar distance. The space rock will fly across the constellation Cepheus at nearly 25,000 mph, near the Little Dipper.
Asteroid 2014 KH39 was discovered on May 24 by Richard Kowalski of the Catalina Sky Survey. Kowalski is the same astronomer who discovered Asteroid 2008 TC3, which exploded 23 miles above the Nubian Desert in Sudan in 2008.
It would have to have struck the earth to become a "meteorite".
The article lacks data on how close it is approaching. In defense,
I would have to say that info wasn't easy to find.
Virtual Telescope says it its closest approach will be 1.3 millions of km.
Its not putting us in danger, but is an excellent example of how large objects
can escape detection.