500 metre-wide asteroid makes close Earth fly-by tonight

JANUARY 26, 2015

An asteroid measuring about half a kilometre in diameter will make a relatively close, but harmless pass by Earth on Monday night, according to the US space agency, NASA.

NASA says the asteroid, which is known as 2004 BL86, will pass about 1.2 million km from Earth, roughly three times farther away than the moon.

Amateur and professional astronomers are preparing to watch the flyby, which will be most visible between 8 pm and 1 am from Africa, the Americas and Europe.

Scientists plan to map the 2004 BL86's surface with radar during the flyby in hopes of learning more about its size, shape, rate of rotation and other features.

A small telescope or binoculars will be needed to see 2004 BL86.

NASA currently tracks more than 11 000 asteroids in orbits that pass relatively close to Earth.

An object of the size of 2004 BL86 is believed to have hit the planet about 65 million years ago in what is now Mexico's Yucatan peninsula, triggering a global climate change that is believed to be responsible for the demise of the dinosaurs and many other forms of life on Earth.

Two years ago, a relatively a small asteroid exploded in the atmosphere over Chelyabinsk, Russia, leaving more than 1 500 people injured by flying glass and debris.