NASA's OSIRIS-REx mission will not only make beautiful photos of the Bennu asteroid, but it will also help scientists learn if the rock will someday endanger the Earth.
There are many reasons to explore asteroids. They could be potential mines for precious resources such as water and heavy elements, and they contain clues that we can learn to learn about the solar system in the earliest days.
But also, big things that get stuck on Earth can have catastrophic consequences. So scientists are also interested in it.
Bennu is an asteroid with a width of 487.68 m, which orbits the Sun fairly close to Earth. OSIRIS-REx, NASA's mission to study it began in September 2016 and reached its goal last Monday. The spacecraft carries five instruments: a camera, a LIDAR system (like radar, but a laser instead of radio waves), and three spectrometers that measure different wavelengths to determine the composition of the asteroid.
Benue is an especially important goal when it comes to his own survival. Approximately every six years, it is relatively close to the Earth ("close" in space, but far from any other measure). The patterns suggest that during his close approaches between 2175 and 2196 he has a 1 in 2700 chance to face us. It's still incredibly small (99,963 percent chance of a pass), but Bennu is a big rock – even the thin chances are too big to ignore when civilization is set.
Why do astronomers not know for sure whether we are safe? There are many strengths, and small differences can change chances. During some of the near-asteroid approaches, Earth's gravity will give him a blow that could shove it off into a collision.
In addition, Yarkowski has an effect, according to a press release from the Jet Laboratory: the uneven solar heating of such a lightweight body can cause changes in its trajectory. It is not clear where Benou will go after 2135.
OSIRIS-REx and Earth's telescopes will continue to characterize the asteroid, tracking its path and determining how Yarkowski's gravity and effect will affect its trajectory. The mission, we hope, will lead to trajectories that are 60 times more accurate than current ones, according to the press release.
What if Bennu becomes a threat? Well, you do not have to worry personally because the chances are very good that you will be dead. Your children are also likely to be dead.
But the researchers are working on several solutions. A mission called the Double Asteroid Redirection Test will try to hit a space ship in an asteroid to cause a change in trajectory. Maybe we could accumulate asteroids.
Or, if we get enough time, we can just paint one side to change how it absorbs solar radiation by using the effect of Yarkowski in our favor.
There is a lot of data that needs to be taken before we know what Benue will do, and many other interesting sciences to be held. But know that Bennu is not the asteroid you should be worried about. Your asteroids You have to worry about those who have not yet been discovered.[NASA JPL]