The spacecraft Osiris-Rex - short for Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer - last Tuesday conducted NASA's first sample collection from an asteroid as part of a seven-year voyage, according to Deutsche press agency (dpa).
It retrieved a large sample from the asteroid Bennu, a black pile of rubble that is about 500 meters wide and 290 million kilometers from Earth, and is expected to bring it to Earth in September 2023 for further study.
NASA said it received images showing spacecraft's collector head "overflowing" with collected material, estimated at "well over" the 60 grams required by the mission, but added that "some of these particles appeared to be slowly escaping from the collection head."
The space agency said that due to the leak - and thanks to the large size of the sample - it decided to bring forward the stowage of the particles in the spacecraft's Sample Return Capsule (SRC) to Tuesday "to minimize further sample loss."
The operation was originally scheduled to take place on November 2.
NASA hopes the 1-billion-dollar mission will reveal secrets about the origins of our solar system. Asteroids are remnants from that era, more than 4.5 billion years ago.
Osiris-Rex was launched from the space port Cape Canaveral in Florida in September 2016. It took about two years to arrive within 20 kilometers of Bennu and a further two to find an ideal spot for collecting the sample.
