Bennu Asteroid

NASA's OSIRIS-REx spacecraft, which collected the dust samples of an asteroid 320 million km from Earth, has started its return-journey on May 11. First launched in 2016, the $800 million spacecraft had found traces of hydrogen and oxygen molecules in asteroid 'Bennu' in 2018. While the NASA mission is expected to reach Earth in two years, currently Japan is the only country to have retrieved asteroid samples back home.