|An artist's view of an Earth-approaching asteroid passing close|
to our planet. ESA / P.Carril
Observations made by NASA's NEOWISE mission have pegged the asteroid at roughly 650 meters (2,000 feet) across and twice as reflective as the Moon. That and its orbit are about all we know about this speeding space mountain for the moment.
That should change very soon. Asteroid 2014 JO25 will be making a close approach to Earth on April 19th. Because of its size and proximity, it will be bright enough to spot in a small, backyard telescope and moving fast enough to see in real time.
Closest approach occurs around 12 UT (7 a.m. CDT) April 19th when it zips by at 1.8 million km (fewer than 1.1 million miles) away, or about four times the distance to the Moon. When darkness falls in Europe and Africa that evening, the asteroid will shine at its peak magnitude of +10.7 along the Ursa Minor–Draco border. Several hours later, North American observers can catch it rolling west across Coma Berenices a hair fainter, between magnitude +10.8 and +11.0.
See Full Source Article at http://www.skyandtelescope.com/observing/see-a-potentially-hazardous-asteroid-from-your-backyard/