OSIRIS-REx spacecraft [Public domain], via Wikimedia CommonsA team led by researchers at the University of Colorado Boulder is studying data from NASA's OSIRIS-REx spacecraft, which approached the big asteroid Bennu months ago.
The OSIRIS-REx team previously expected a generally smooth surface with a few large boulders on Bennu, but it turned out that Bennu's entire surface is rough and dense with boulders. Scientists and engineers on the USA -led OSIRIS-REx and the Japanese-led Hayabusa2 missions are having to scramble to adjust their sample acquisition plans now that the probes are at their destinations and finding unexpected environments.
"We go back to the drawing board and start thinking again", Dante Lauretta, the head of the mission, told a press conference.
NASA's OSIRIS-REx spacecraft made an astonishing discovery about the asteroid it has been orbiting since December: the rock is actively spewing material out into space. It might even help us in our search for clues to the origins of life, thus, it is the target of the OSIRIS-REx mission which is meant to return samples to Earth in 2023 for further study.
Bits of material were first spotted floating up from Bennu on January 6, shortly after OSIRIS-REx went into an orbit that brought about a mile away from the quarter-mile-wide asteroid. Studying asteroids like Bennu to learn about the origin of the solar system.
The three-month observation as the spacecraft rotated Bennu has already produced multiple discoveries. The asteroid's surface is like a time capsule with different regions representing different eras, from the remains of Bennu's parent asteroid to recent activity.
The team also says they found more boulders at the surface than expected. NASA finds this asteroid particularly important because scientists believe its chemical composition may be similar to that of asteroids which brought carbon and other building blocks of life to Earth. "We're nonetheless studying the way to the course of the information, analyze the knowledge, and make sense of what's occurring at this asteroid".
The OSIRIS-REx team also did not anticipate the number and size of boulders on Bennu's surface. Among the particles thrown off, Bennu falls again to the asteroid's floor. "Bennu has issued us a challenge to deal with its rugged terrain, and we are confident that OSIRIS-REx is up to the task".
The rocks and pebbles seen flying off Bennu vary from a couple of centimeters throughout to tens of centimeters in dimension - roughly the scale of an M&M as much as a laptop computer pc - with speeds of as much as some miles per hour, in line with Lauretta.
"Thanks to the parallel missions of Hayabusa2 and OSIRIS-REx, we can finally address the question of how these two asteroids came to be", Sugita said. As a result, Bennu's rotation period is decreasing by about one second every 100 years. Without the equipment to pulverize these hunks of rock, OSIRIS-REx might be ill-equipped to navigate the terrain for touchdown. Rich Burns, OSIRIS-REx project manager at NASA's Goddard Space Flight Center and Coralie Adam, OSIRIS-REx flight navigator with KinetX, Inc. expressed confidence that the navigation and operations teams will be able to more accurately target the descent and achieve a "Bullseye TAG" in the summer of 2020.