An asteroid, named Bennu, that could one day cause significant damage to the Earth in the 22nd century will be cozying up near Mars on Valentine's Day. So if you have a telescope handy, you may be able to catch a faint glimpse of the asteroid that NASA is keeping a close eye on.
NASA estimated that Bennu will come close enough to Earth and pose a 1 in 2,7000 chance of impacting the planet between the years 2175 and 2196. "Put another way, those odds mean there is a 99.963 percent chance the asteroid will miss the Earth. Even so, astronomers want to know exactly where Bennu is located at all times," NASA said in a press release.
NASA launched an unmanned spacecraft in September 2016 to study Bennu and the possible impact it could have on Earth. OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security – Regolith Explorer) spent two years traveling 1.2 billion miles towards Bennu and eventually reached the asteroid two years later.
In December 2018, OSIRIS-REx switched from flying towards to Bennu to orbiting 11.8 miles around the asteroid and on Dec. 31 it entered the asteroid's orbit — making Bennu the smallest object ever to be orbited by a spacecraft.
"The team continued our long string of successes by executing the orbit-insertion maneuver perfectly," said Dante Lauretta, OSIRIS-REx principal investigator. "With the navigation campaign coming to an end, we are looking forward to the scientific mapping and sample site selection phase of the mission."
Over the next several months, OSIRIS-REx will conduct flyovers around the asteroid — getting as close as 4 miles from the surface — and capture high-resolution of every square inch in order to determine the best sampling site. The main goal is to analyze the asteroid's mass and spin rate. Then, NASA hopes to briefly touch Bennu's surface in order to collect a sample in 2020.
Why is NASA so interested in this asteroid?
Bennu may offer additional insights into the formation of our solar system.
"On planets like Earth, the original materials have been profoundly altered by geologic activity and chemical reactions with our atmosphere and water," said Edward Beshore, deputy principal investigator for OSIRIS-REx. "We think Bennu may be relatively unchanged, so this asteroid is like a time capsule for us to examine."
If Bennu were to crash into Earth, scientists estimate the asteroid's impact would be 4,000-5000 times more powerful than the Chelyabinsk meteor that dramatically exploded over Russia in 2013. While certainly not a world-threatening event (it's estimated that it would take an object 60 miles wide to completely wipe out life on Earth), Bennu's impact on an urban population center would likely be apocalyptic.
"If astronomers someday identify an asteroid that presents a significant impact hazard to Earth, the first step will be to gather more information about that asteroid," added Beshore. "Fortunately, the OSIRIS-REx mission will have given us the experience and tools needed to do the job."
Editor's note: This article has been updated since it was originally published in August 2016.