The sample collection process was a carefully arranged dance. Osiris-Rex extends its 2 m (6.6 ft) tagsam robotic arm by attaching a 30 cm (1 ft) wide sample head and folding it over the solar panels to protect it. The probe then slowly reaches the surface, finally touching down within a single meter (3.3 ft) of the selected target. The entire process was monitored by a Samcam imaging camera mounted above the arm.
The camera shows Tagsam approaching the head and penetrating Bennu’s surface at a speed of just 0.2 mph. At first, it appears to break up some of the porous rocks below, and then a moment later throws up a bottle of nitrogen gas. It “stirs up a significant amount of material from the sample site,” NASA said. It took five to six seconds to collect the material, most of which were collected within the first three seconds.
The head is designed to hold and store agitated surface material. To confirm the presence of regolith, Osiris-Rex will first take a picture of the collector head, and then on Saturday, measure the mass of rock and dust by rotating it like a centrifuge on its axis.
NASA said the sample was “as good as we thought” because it smashed a lot of material that needed to be stored in the sample chamber. Scientists have already learned a lot about Benu by watching the video of the crash, but it will take three years for the spacecraft to return to Earth before examining what actually built it.