By Heather Mendiola
On Monday, Jan. 26, 2015, Asteroid 2004 BL86 will fly by Earth at a safe distance of 1.2 million kilometers (745,000 miles) away, the closest it will get to Earth in the next 200 years. From the reflected brightness, astronomers estimate that the asteroid is about 0.5 kilometers (a third of a mile) in size. NASA stated that the passing of asteroid 2004 BL86 will be the closest by any known space rock this large until 2027, when Asteroid 1999 AN10 will pass Earth.
The 2004 BL86 asteroid was discovered on Jan. 30, 2004, by a telescope at the Lincoln Near-Earth Asteroid Research facility in White Sands, N.M. The Near-Earth Object Program discover these objects, characterize their subsets and identify their approaches that are close in order to determine whether they are hazardous to the planet.
Though 2004 BL86 will safely pass by Earth, NASA has an Asteroid Defense Plan in case an asteroid’s path is headed straight for Earth. In 2005, the U.S. Congress asked NASA to develop plans for preventing an asteroid from colliding with Earth.
NASA presented their ideas at the Planetary Defense Conference in 2007, and some of the plans used nuclear explosives. Nuclear explosives were chosen due to the amount of energy they produce, in hopes that the explosion would provide enough momentum to shift the asteroid’s course enough to prevent a collision with Earth.
After testing four different nuclear explosion scenarios, NASA determined a series of standoff nuclear explosions, where the bomb does not come in contact with the asteroid, would be the most effective way to deflect the asteroid.
The best non-nuclear idea was kinetic impact, or ramming giant objects at the asteroid, which requires knowledge of the surface of the asteroid that NASA does not posses. Other ideas were to use a laser or a giant mirror to focus energy on a certain point in order to “boil off” parts of the asteroid, or to use a spacecraft to tug the asteroid off course.
According to NASA’s website, Lance Benner, the principal investigator at the Gladstone radar stated, “We know almost nothing about the asteroid.” NASA’s Deep Space Network antenna at Goldstone, Calif., and the Arecibo Observatory in Puerto Rico intend to acquire data and radar-generated images in order to learn more about the asteroid. NASA scientists also intend to observe 2004 BL86 with microwaves in order to learn more about this asteroid.
The asteroid will be observable through small telescopes and strong binoculars around 11 p.m. EST on Monday, Jan. 26, 2015. When the asteroid is brightest, it will be located in the constellation Cancer and its motion will be obvious to observers against the stars.