Asteroid 2004 BL86 Makes Close, But Not Too Close, Approach To Earth Monday

An asteroid roughly 1,640 feet in size will make a close approach to Earth Monday. Asteroid 2004 BL86 poses no threat to Earth and will pass safely by the planet at a distance of around 745,000 miles. The asteroid will be the largest known object to approach this close to Earth until 2027, when asteroid 1999 AN10 will pass 240,000 miles from Earth.

These close approaches let researchers gain new insights into asteroids and life on Earth. The origin of Earth's water has always been something of a mystery, with scientists hypothesizing either comets or asteroids brought water to the planet. A new study analyzing the water composition on comet 67P/Churyumov-Gerasimenko has led scientists to believe ancient asteroids are responsible for Earth's water. The chemical signature of comet 67P's water was much different compared with water found on Earth.

"Asteroids are something special. Not only did asteroids provide Earth with the building blocks of life and much of its water, but in the future, they will become valuable resources for mineral ores and other vital natural resources. They will also become the fueling stops for humanity as we continue to explore our solar system," Don Yeomans, manager of NASA's Near-Earth Object Program Office at the Jet Propulsion Laboratory, said in a statement. NASA will use the Deep Space Network antenna at Goldstone, California, and the Arecibo Observatory in Puerto Rico to track the asteroid as it makes its close approach to Earth.

Microwaves sent from Arecibo Observatory and the Deep Space Network will "touch" the asteroid to create radar images of the space rock. "From them we can generate detailed three-dimensional models of the object, define its rotation precisely and get a good idea of its internal density distribution. You can even make out surface features. A good echo can give us a spatial resolution finer than 10 meters," Dr. Steve Ostro, Jet Propulsion Laboratory radar astronomer, explained in a statement.

Asteroid 2004 BL86 was discovered on Jan. 30, 2004, by the Lincoln Near-Earth Asteroid Research. The asteroid will not get this close to Earth for another 200 years.