OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) is a NASA asteroid sample return mission. The spacecraft launched on September 8, 2016, and will arrive at the carbonaceous asteroid Bennu in 2018. It will collect a sample of at least 60 grams (2.1 oz) from Bennu’s surface, and return it to Earth in 2023 for further study.
The mission is designed to investigate how planets formed and evolved, as well as to improve our understanding of asteroids that could impact Earth. OSIRIS-REx will be the first U.S. mission to return samples from an asteroid since the Apollo era, and will provide valuable data for planetary science research for decades to come.
Asteroids are primitive remnants of the solar system formation process that can provide insights into its history. Bennu specifically is an important target because it is a carbonaceous asteroid, which makes up about 75% of known asteroids and comets. Carbonaceous asteroids are thought to be some of the most primitive objects in the solar system, containing organic molecules that may have played a role in the origin of life on Earth. In addition, this type of asteroid is also believed to be potential sources of water and other vital resources for future exploration missions.
Bennu was selected as the target for OSIRIS-REx based on several criteria: its orbit brings it relatively close to Earth every six years; ground-based observations suggest that it contains a wealth of carbon-bearing materials; models indicate a good likelihood that Bennu has remained largely unaltered since its formation billions of years ago; finally, remote sensing data suggests there is a smooth area on Bennu’s surface where a sample could be collected without riskof damaging the spacecraft .
The OSIRIS-REx spacecraft arrived at Bennu after completing a 2 year journey through our solar system using Earth gravity assists and rocket burns . On December 3rd , 2018 ,the spacecraft entered into orbit around Bennu – beginning 400 days(~ 1 year )of mapping operations . This phase culminated with selectionof Osprey site as primary sampling location . Following finalapproach maneuvers ,on October 20th , 2020 ,the Touch And Go(TAG) sequence commenced : during this 7 second operationthe Sample Acquisition Mechanism (SAM) extended itselfto briefly touch down onto regolith particles before firing ascentengines back into space – thereby acquiring material fromBennus’surface . Ascent engine firing lasted approximately 17 minutesand resulted in successful stowingof TAGSAM head inside containment vessel ; over 2 ouncesof regolith were acquired during touchdown .Following stowage SAM began rechargingits power supply via exposureto sunlight –a processthat requires ~60 days prior tobeginning descent towardEarth .On March10th2021descent engineswill fireslowly over periodof 12 minutesin order tomatch velocity withEarth prior tobraking burnon entryinto atmosphereat end offlight plan currentlyscheduledfor September24th2023 . Aftersuccessful parachuteassisted landingin Utah desertUSA RETURN Capsule carryingregolith sampleswill beseparatedfrom ServiceModulewhich remainsin orbit aroundearth ; followingrecovery capsulecarrying sampleswill betransportedby Air ForceConvair C-5MSuper Galaxyor alternatemilitary transportto JohnsonSpace Centerin HoustonTexas where curationfacilityis locatedpriorto allocationtoscientific communityfor research