This summer season, the OSIRIS-REx spacecraft will carry out NASA’s first-ever effort to touch the surface area of an asteroid, accumulate an example of it, as well as securely retreat. But because reaching asteroid Bennu over a year back, the goal group has actually been taking on an unanticipated difficulty: how to complete this task at an asteroid whose surface area is buried in building-sized stones.
Using these dangerous stones as signposts, the goal group established a brand-new accuracy navigating technique to get rid of the difficulty.
The OSIRIS-REx group had actually initially prepared to utilize a LIDAR system to navigate to Bennu’s surface area throughout the Touch-And-Go (TAG) example collection occasion. LIDAR is comparable to radar, however it utilizes laser pulses instead of radio waves to procedure range. The OSIRIS-REx Guidance, Navigation, as well as Control (GNC) LIDAR is made to navigate the spacecraft to a reasonably hazard-free surface area. The goal had actually initially pictured a touchdown website 164 feet (50 meters) in size, however the biggest risk-free locations on Bennu are a lot smaller sized. The most significant website is simply 52 feet (16 m) vast, or about 10% of the risk-free location pictured. The group recognized that they required a much more accurate navigating method that would certainly permit the spacecraft to properly target extremely little websites while evading possible dangers.
In the face of this difficulty, the OSIRIS-REx group switched over to a brand-new navigating technique called Natural Feature Tracking (NFT). NFT gives extra considerable navigating abilities than LIDAR, as well as is vital for performing what the group is calling “Bullseye TAG,” which supplies the spacecraft to the much smaller sized tasting location. As an optical navigating method, it needs the development of a high-resolution photo magazine onboard the spacecraft.
Earlier this year, the spacecraft made reconnaissance overlooks the goal’s key as well as backup example collection websites, marked Nightingale as well as Osprey, flying as close as 0.4 miles (625 m) over the surface area. During these overpass, the spacecraft accumulated pictures from various angles as well as illumination problems to total the NFT photo magazine. The group utilizes this magazine to determine stones as well as craters one-of-a-kind to the example website area, as well as will post this info to the spacecraft prior to the example collection occasion. NFT autonomously overviews the spacecraft to Bennu’s surface area by contrasting the onboard photo magazine with the real-time navigating pictures taken throughout descent. As the spacecraft comes down to the surface area, NFT updates its anticipated factor of get in touch with depending on the spacecraft’s setting in relationship to the spots.
On the ground, employee developed “hazard maps” for both the Nightingale as well as Osprey websites to record every one of the surface area includes that might possibly hurt the spacecraft, like huge rocks or high inclines. The group utilized the photo magazine along with information from the OSIRIS-REx Laser Altimeter (OLA) to produce 3D maps that carefully design Bennu’s topography. As component of NFT, these maps record rock elevations as well as crater midsts, as well as overview the spacecraft far from possible dangers while targeting an extremely little website. During descent, if the spacecraft anticipates it will touch harmful surface, it will autonomously wave-off as well as retreat from the surface area. However, if it sees that the location is without dangers, it will proceed to descend as well as effort to accumulate an example.
NFT will be utilized in April to navigate the spacecraft throughout its very first example collection wedding rehearsal. The procedures group executed initial screening throughout the Orbital B goal stage in late 2019, as well as the outcomes showed that NFT operates in real-life problems as made. NFT will likewise be utilized for navigating throughout the 2nd wedding rehearsal prepared for June.
OSIRIS-REx’s very first example collection effort is arranged for lateAugust The spacecraft will leave Bennu in 2021 as well as is arranged to provide the example to Earth in September 2023.
NASA’s Goddard Space Flight Center in Greenbelt, Maryland, gives total goal monitoring, systems design, as well as the safety and security as well as goal guarantee forOSIRIS-REx Dante Lauretta of the University of Arizona, Tucson, is the major detective, as well as the University of Arizona likewise leads the scientific research group as well as the goal’s scientific research monitoring preparation as well as information handling. Lockheed Martin Space in Denver constructed the spacecraft as well as gives trip procedures. Goddard as well as KinetX Aerospace are accountable for browsing the OSIRIS-REx spacecraft. OSIRIS-REx is the 3rd goal in NASA’s New Frontiers Program, which is taken care of by NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the company’s Science Mission Directorate in Washington.