OSIRIS-REx was launched on 8September 2016,flew past Earth on 22September 2017,and rendezvoused with Bennu on 3December 2018.[17] It spent the next two years analyzing the surface to find a suitable site from which to extract a sample. On 20October 2020,OSIRIS-REx touched down on Bennu and successfully collected a sample.[18][19][20][21] OSIRIS-REx left Bennu on 10May 2021[22][23] and returned its sample to Earth on 24September 2023,[24] subsequently starting its extended mission to study 99942 Apophis,where it will arrive in April 2029.
Bennu was chosen as the target of study because it is a "time capsule" from the birth of the Solar System.[25] Bennu has a very dark surface and is classified as a B-type asteroid,a sub-type of the carbonaceous C-type asteroids. Such asteroids are considered primitive,having undergone little geological change from their time of formation. In particular,Bennu was selected because of the availability of pristine carbonaceous material,a key element in organic molecules necessary for life as well as representative of matter from before the formation of Earth. Organic molecules,such as amino acids,have previously been found in meteorite and comet samples,indicating that some ingredients necessary for life can be naturally synthesized in outer space.[1]
The cost of the OSIRIS-REx mission is approximately US$800million,[26] not including the AtlasV launch vehicle,which is about US$183.5million.[27] The OSIRIS-APEX extended mission costs an additional US$200million.[16] It is the third planetary science mission selected in the New Frontiers program,after Juno and New Horizons. The principal investigator is Dante Lauretta[28] from the University of Arizona,having taken over in 2011 after the original PI Michael Julian Drake died four months after the mission won approval from NASA.
OSIRIS-REx was the first United States spacecraft to return samples from an asteroid. Previous asteroid returns include the Japanese probes Hayabusa,which visited 25143 Itokawa in 2010;and Hayabusa2,which visited 162173 Ryugu in June 2018.
After traveling for approximately two years,the spacecraft rendezvoused with asteroid 101955 Bennu in December2018,[30] and began 505days of surface mapping at a distance of approximately 5km (3.1mi).[1] Results of that mapping were used by the mission team to select the site from which to take a sample of the asteroid's surface.[31] Then a close approach (without landing) was carried out to allow extension of a robotic arm to gather the sample.[32]
Following the collection of material (121.6grams),[11] the sample was returned to Earth in a 46kg (101lb) capsule similar to that which returned the samples of Comet 81P/Wild on the space probe Stardust. The return trip to Earth was shorter than the outbound trip. The capsule landed by parachute at the Utah Test and Training Range on September 24,2023 and was transported to the Johnson Space Center for processing in a dedicated research facility.[1]
Asteroid Bennu,imaged by the OSIRIS-REx probe,3December 2018
OSIRIS-REx entered the cruise phase shortly after separation from the launch vehicle,following successful solar panel deployment,propulsion system initiation,and establishment of a communication link with Earth.[34] Its hyperbolic escape speed from Earth was about 5.41km/s (3.36mi/s).[35] On 28December 2016,the spacecraft successfully performed its first deep space maneuver to change its velocity by 431m/s (1,550km/h) using 354kg (780lb) of fuel.[36][37] An additional,smaller firing of its thrusters on 18January 2017 further refined its course for an Earth gravity assist on 22September 2017.[36] The cruise phase lasted until its encounter with Bennu in December 2018,[30] after which it entered its science and sample collection phase.[36]
During its cruise phase,OSIRIS-REx was used to search for a class of near-Earth objects known as Earth-Trojan asteroids as it passed through Sun–Earth L4Lagrange point. Between 9–20February 2017,the OSIRIS-REx team used the spacecraft's MapCam camera to search for the objects,taking about 135survey images each day for processing by scientists at the University of Arizona. The search was beneficial even though no new trojans were found,[38] as it closely resembled the operation required as the spacecraft approached Bennu,searching for natural satellites and other potential hazards.[37][39] On 12February 2017,while 673×10^6km (418×10^6mi) from Jupiter,the PolyCam instrument aboard OSIRIS-REx successfully imaged the giant planet and three of its moons,Callisto,Io,and Ganymede.[40]
On 3December 2018,NASA confirmed that OSIRIS-REx had matched the speed and orbit of Bennu at a distance of about 19km (12mi),effectively reaching the asteroid. OSIRIS-REx performed closer passes of the Bennu surface,initially at about 6.5km (4.0mi) through December to further refine the shape and orbit of Bennu. Preliminary spectroscopic surveys of the asteroid's surface by the OSIRIS-REx spacecraft detected the presence of hydrated minerals in the form of clay. While researchers suspect that Bennu was too small to host water,the hydroxyl groups may have come from water present in its parent body before Bennu split off.[42][43]
OSIRIS-REx entered orbit around Bennu on 31December 2018 at about 1.75km (1.09mi) to start its extensive remote mapping and sensing campaign for the selection of a sample site. This is the closest distance that any spacecraft has orbited a celestial object,closer than the Rosetta's orbit of comet 67P/Churyumov–Gerasimenko at 7km (4.3mi).[17][44] At this altitude,it took the spacecraft 62hours to orbit Bennu.[45] At the end of its detailed survey,the spacecraft entered a closer orbit with a radius of 1km (0.62mi).[46]
Artist's concept of TAGSAM instrument in operation
Procedure
Rehearsals were performed before sampling, during which the solar arrays were raised into a Y-shaped configuration to minimize the chance of dust accumulation during contact and provide more ground clearance in case the spacecraft tipped over (up to 45°) during contact.[29] The descent was very slow, minimizing thruster firings prior to contact to reduce the likelihood of asteroid surface contamination by unreacted hydrazine propellant. Contact with the surface of Bennu was detected using accelerometers, and the impact force was dissipated by a spring in the TAGSAM arm.[47]
Upon surface contact by the TAGSAM instrument, a burst of nitrogen gas was released, to blow regolith particles smaller than 2cm (0.8in) into the sampler head at the end of the robotic arm. A five-second timer limited the collection time to mitigate the chance of a collision, and the probe then executed a back-away maneuver to depart safely.[29]
The plan was then for OSIRIS-REx to perform a braking maneuver a few days later to halt the drift away from the asteroid in case it was necessary to return for another sampling attempt. It would then take images of the TAGSAM head to verify a sample had been acquired. If a sample was acquired, the spacecraft would rotate about the short axis of the sample arm to determine sample mass by measuring momentum of inertia and determine if it was in excess of the required 60g (2.1oz).
Both the braking and rotation maneuvers were canceled when images of the sample container clearly showed a large excess of material was collected, some of which was able to escape through the container's seal because some material had jammed the mechanism open. The collected material was scheduled for immediate storage in the Sample-Return Capsule.[48][29] On 28October 2020, the sample collector head was secured in the return capsule. Following the separation of the head from the collector arm, the arm was retracted into its launch configuration, and the Sample-Return Capsule lid was closed and latched preparing to return to Earth.[49][50]
In addition to the bulk sampling mechanism, contact pads on the end of the sampling head made of tiny stainless steel loops (Velcro)[51] passively collected dust grains smaller than 1mm.
Operations
The final four candidate sample sitesThe successful October 2020 sample collection, showing OSIRIS-REx touching down on the Nightingale sample siteSample collection as seen by the navigation camera (00:47; October 20, 2020)Images of the TAGSAM head showing that it is full of rocks and dust collected from Bennu and that it is leaking material into spaceOSIRIS-REx successfully stows its sample of asteroid Bennu in October 2020.The sample container closes.
NASA selected the final four candidate sample sites in August 2019, named Nightingale, Kingfisher, Osprey, and Sandpiper.[52] On 12 December 2019, they announced that Nightingale had been selected as the primary sample site and Osprey was selected as the backup site.[53] Both were within craters, with Nightingale near Bennu's north pole while Osprey was near the equator.[54]
NASA planned to perform the first sampling in late August 2020;[55] NASA's originally planned Touch-and-Go (TAG) sample collection was scheduled for 25 August 2020, but was rescheduled for 20 October 2020, at 22:13 UTC.[56][57] On 15 April 2020, the first sample collection rehearsal was successfully performed at the Nightingale sample site. The exercise took OSIRIS-REx as close as 65m (213ft) from the surface before performing a back-away burn.[58][59] A second rehearsal was successfully completed on 11 August 2020, bringing OSIRIS-REx down to 40m (130ft) from the surface. This was the final rehearsal before the sample collection scheduled for 20 October 2020, at 22:13 UTC.[60][61]
At 22:13UTC, on 20October 2020, OSIRIS-REx successfully touched down on Bennu at a distance of 200million miles (320million kilometers) from Earth.[62][63] NASA confirmed via images taken during sampling that the sampler had made contact. The spacecraft touched down within 92cm (36in) of the target location.[64][65] A sample of the asteroid which was estimated to weigh at least 2 ounces (57 grams) was collected by OSIRIS-REx following the touch down.[18] After imaging the TAGSAM head, NASA concluded that there were rocks wedged in the mylar flap meant to keep the sample inside, causing the sample to slowly escape into space.[66] In order to prevent further loss of the sample through the flaps, NASA canceled the previously planned spinning maneuver meant to determine the mass of the sample as well as a navigational braking maneuver, and decided to stow the sample on 27October 2020 rather than 2November 2020 as originally planned, which was completed successfully. The collector head was observed hovering over the Sample Return Capsule (SRC) after the TAGSAM arm moved it into the proper position for capture, and the collector head was later secured onto the capture ring in the SRC.[66]
When the head was seated into the Sample-Return Capsule's capture ring on 28 October 2020, the spacecraft performed a "backout check", which commanded the TAGSAM arm to back out of the capsule. This maneuver is designed to tug on the collector head and ensure that the latches – which keep the collector head in place – are well secured. Following the test, the mission team received telemetry confirming that the head was properly secured in the Sample-Return Capsule. Thereafter, on 28 October 2020, two mechanical parts on the TAGSAM arm were disconnected – these are the tube that carried the nitrogen gas to the TAGSAM head during sample collection and the TAGSAM arm itself. Over the next several hours, the mission team commanded the spacecraft to cut the tube that stirred up the sample through the TAGSAM head during sample collection, and separate the collector head from the TAGSAM arm. Once the team confirmed these activities were done, it commanded the spacecraft on 28 October 2020, to close and seal the Sample-Return Capsule, the final step of the sample stowage process of Bennu's samples.[67] To seal the SRC, the spacecraft closed the lid and then secured two internal latches. On inspecting images, it was observed that a few particles had escaped from the collector head during the stowage procedure, but it was confirmed that no particles would hinder the stowage process, since the team was confident that a plentiful amount of material remained inside of the head, more than the 60g (2.1oz) needed, that is, 121.6g (4.29oz).[11] The sample of Bennu was safely stored and ready for its journey to Earth. With the collector head secure inside the SRC, pieces of the sample would no longer be lost.[68]
Sample return
Two members of the recovery team examine the return capsule after landing
Close-up photo of the return capsule upon landing
Expected landing area of return capsule in Utah
On 7April 2021, OSIRIS-REx completed its final flyover of Bennu and began drifting away from the asteroid.[69] On 10May 2021, the spacecraft departed the vicinity of Bennu and began its two-year journey to Earth with the asteroid sample.[70][71][72]
On 24 September 2023, at 4:42a.m. MDT (UTC-06:00), at a distance of 63,000 miles (101,000 kilometers) from Earth, it ejected the sample return capsule, which re-entered the atmosphere at 27,650 miles per hour (44,500km/h).[73] Due to a mistake in wiring, the drogue parachute did not deploy as planned at 100,000 feet (30,400 meters).[74] However, the main parachute was released when the spacecraft reached about 9,000 feet (2,700 meters), and it survived deployment despite higher than anticipated speeds.[74] About 8:52a.m. MDT the capsule landed at 11mph (18km/h) at the Utah Test and Training Range, one minute earlier than predicted.[74][75][76] The main spacecraft maneuvered to a trajectory away from Earth for its extended mission to Apophis in 2029 called OSIRIS-APEX.[77]
On 11 October 2023, the recovered capsule was opened to reveal a "first look" at the asteroid sample contents.[12] Further looks were reported on 13 December 2023 and revealed organic molecules and unknown materials that require study to determine their composition.[79][80]
Some damaged fasteners prevented immediate opening, but, after three months, on 13 January 2024, NASA reported fully opening the recovered container.[81][82] In total, 121.6g (4.29oz) of asteroidal material was recovered from the sample container.[11][83]
Extended mission
On 25 April 2022, NASA confirmed that the mission would be extended. After dropping off its sample to Earth on 24 September 2023, the mission became OSIRIS-APEX ('APophis EXplorer').[77] As its new name suggests, its next target will be the near-Earth asteroid (and potentially hazardous object) 99942 Apophis. Apophis will make an extremely close pass to the Earth on 13 April 2029. Observations of Apophis will commence on 8 April 2029, and a few days later, on 21 April, OSIRIS-APEX is planned to rendezvous with the asteroid.[84] OSIRIS-APEX will orbit Apophis for around 18 months in a regime similar to that at Bennu. The spacecraft will perform a maneuver, similar to sample collection at Bennu, by using its thrusters to disturb Apophis's surface, in order to expose and spectrally study the subsurface and the material beneath it.[16]
Animation of OSIRIS-APEX
Around the Sun
Around 99942 Apophis
OSIRIS-APEX· 99942 Apophis·Earth·Sun
Name
OSIRIS-REx and OSIRIS-APEX are acronyms, and each letter or combination of letters relates to part of the respective projects:[85]
O – Origins
SI – Spectral Interpretation
RI – Resource Identification
S – Security
REx – Regolith Explorer
APEX – Apophis Explorer
Each of these words was chosen to represent an aspect of this mission.[85] For example, the S, for security means the security of Earth from impact by hazardous near-Earth objects (NEOs).[85] Specifically it refers to better understanding the Yarkovsky effect, which can alter the trajectories of orbiting bodies.[85] Regolith Explorer means that the mission will study the texture, morphology, geochemistry, and spectral properties of the regolith of asteroid Bennu while Apophis Explorer corresponds to the study of Apophis asteroid.[85]
When its heritage concept was proposed in the Discovery Program in 2004, it was called only OSIRIS, with REx for "Regolith Explorer" used descriptively rather than as part of the name.[86]
The asteroid for the second mission is named after the ancient Egyptian god Apophis, who was associated with chaos and destruction.[87] The mission name itself was a reference to the god Osiris. Dante Lauretta, deputy PI of the mission, was called "a mythology buff" by the mission PI Michael Drake: "he was doodling on a pad and trying to capture the principal themes of what we are trying to do with this mission study life origins, identify resources, planetary security in the form of asteroid deflection and he realized he got the name of Osiris out of that, an ancient god of Egypt who may have been one of the first pharaohs."[88][89]
Return and analyze a sample of pristine carbonaceous asteroid regolith in an amount sufficient to study the nature, history, and distribution of its constituent minerals and organic compounds
Map the global properties, chemistry, and mineralogy of a primitive carbonaceous asteroid to characterize its geologic and dynamic history and provide context for the returned samples
Measure the Yarkovsky effect (a thermal force on the object) on a potentially hazardous asteroid and constrain the asteroid properties that contribute to this effect
Characterize the integrated global properties of a primitive carbonaceous asteroid to allow for direct comparison with ground-based telescopic data of the entire asteroid population
Telescopic observations have helped define the orbit of 101955 Bennu, a near-Earth object (NEO) with a mean diameter in the range of 480 to 511m (1,575 to 1,677ft).[91] It completes an orbit of the Sun every 436.604days (1.2years). This orbit takes it close to the Earth every six years. Although the orbit is reasonably well known, scientists continue to refine it. It is critical to know the orbit of Bennu because recent calculations produced a cumulative probability of 1 in 1410 (or 0.071%) of impact with Earth from 2169 to 2199.[92] One of the mission objectives is to refine understanding of non-gravitational effects (such as the Yarkovsky effect) on this orbit, and the implications of those effects for Bennu's collision probability. Knowing Bennu's physical properties will be critical for future scientists to understand when developing an asteroid impact avoidance mission.[93]
Power: Two solar arrays generate 1226 to 3000Watts, depending on the spacecraft's distance from the Sun. Energy is stored in Li-ion batteries.[2]
Propulsion system: Based on a hydrazine monopropellant system developed for the Mars Reconnaissance Orbiter, carrying 1,230kg (2,710lb) of propellant and helium.[94]
The sample-return capsule reentered the Earth's atmosphere with a parachute assisted landing. The capsule with encased samples was retrieved from Earth's surface and is being studied, as was done with the Stardust mission.
Instruments
In addition to its telecommunication equipment, the spacecraft carries a suite of instruments to image and analyze the asteroid on many wavelengths,[95] and retrieve a physical sample to return to Earth. The Planetary Society coordinated a campaign to invite interested persons to have their names or artwork on the mission's spirit of exploration saved on a microchip now carried in the spacecraft.[96]
OCAMS
Imaging camera suite
The OSIRIS-REx Camera Suite (OCAMS) consists of the PolyCam, the MapCam, and the SamCam.[95] Together, they acquire information on asteroid Bennu by providing global mapping, sample site reconnaissance and characterization, high-resolution imaging, and records of the sample acquisition.[97]
PolyCam, an 20cm (7.9in) telescope, acquired visible-light images with increasingly higher resolution on approach the asteroid and high-resolution surface images from orbit
MapCam searches for satellites and outgassing plumes. It maps the asteroid in four blue, green, red and near infrared channels, and informs the model of Bennu's shape and provides high resolution imaging of the potential sample sites
SamCam continuously documents the sample acquisitions
OVIRS
OVIRS
The OSIRIS-REx Visible and IR Spectrometer (OVIRS) is a spectrometer which maps minerals and organic substances on the asteroid's surface.[95] It provides full-disc asteroid spectral data at 20m resolution. It maps blue to near-infrared, 400–4300 nm, with a spectral resolution of 7.5–22 nm.[98] This data will be used in concert with OTES spectra to guide sample-site selection. The spectral ranges and resolving powers are sufficient to provide surface maps of carbonates, silicates, sulfates, oxides, adsorbed water and a wide range of organic compounds.[citation needed]
OTES
OTES
The OSIRIS-REx Thermal Emission Spectrometer (OTES) provides thermal emission spectral maps and local spectral information of candidate sample sites in the thermal infrared channel covering 4–50µm, again to map mineral and organic substances.[95] The wavelength range, spectral resolution, and radiometric performance are sufficient to resolve and identify silicates, carbonates, sulfates, phosphates, oxides, and hydroxide minerals. OTES is also used to measure the total thermal emission from Bennu in support of the requirement to measure emitted radiation globally.[citation needed]
Based on the performance of Mini-TES in the dusty surface environment of Mars, OTES was designed to be resilient to extreme dust contamination on the optical elements.[citation needed]
REXIS
The Regolith X-ray Imaging Spectrometer (REXIS) will provide an X-ray spectroscopy map of Bennu to map element abundances.[95] REXIS is a collaborative development by four groups within Massachusetts Institute of Technology (MIT) and Harvard University, with the potential to involve more than 100students throughout the process. REXIS is based on flight heritage hardware, thereby minimizing elements of technical risk, schedule risk, and cost risk.[99]
REXIS is a coded aperture soft X-ray (0.3–7.5 keV) telescope that images X-ray fluorescence line emission produced by the absorption of solar X-rays and the solar wind with elements in the regolith of Bennu leading to local X-ray emissions. Images are formed with 21arcminute resolution (4.3m spatial resolution at a distance of 700m). Imaging is achieved by correlating the detected X-ray image with a 64×64element random mask (1.536mm pixels). REXIS will store each X-ray event data in order to maximize the data storage usage and to minimize the risk. The pixels will be addressed in 64×64bins and the 0.3–7.5keV range will be covered by five broad bands and 11narrow line bands. A 24-second resolution time tag will be interleaved with the event data to account for Bennu rotation. Images will be reconstructed on the ground after downlink of the event list. Images are formed simultaneously in 16energy bands centered on the dominant lines of abundant surface elements from O-K (0.5keV) to Fe-Kß (7keV) as well the representative continuum. During orbital phase5B, a 21-day orbit 700m from the surface of Bennu, a total of at least 133events/asteroid pixel/energy band are expected under 2keV; enough to obtain significant constraints on element abundances at scales larger than 10 m.[citation needed]
On 11November 2019, while observing the asteroid with REXIS, university students and researchers involved in the mission unexpectedly discovered an X-ray burst from a black hole named MAXI J0637-430 located 30,000light-years away.[100]
OLA
The OSIRIS-REx Laser Altimeter (OLA) is a scanning and lidar instrument that will provide high resolution topographical information throughout the mission.[95] The information received by OLA creates global topographic maps of Bennu, local maps of candidate sample sites, ranging in support of other instruments, and support navigation and gravity analyses.[citation needed]
OLA scans the surface of Bennu at specific intervals to rapidly map the entire surface of the asteroid to achieve its primary objective of producing local and global topographic maps. The data collected by OLA will also be used to develop a control network relative to the center of mass of the asteroid and to enhance and refine gravitational studies of Bennu.[citation needed]
OLA has a single common receiver and two complementary transmitter assemblies that enhance the resolution of the information brought back. OLA's high-energy laser transmitter is used for ranging and mapping from 1 to 7.5km (0.62 to 4.66mi). The low-energy transmitter is used for ranging and imaging from 0.5 to 1km (0.31 to 0.62mi). The repetition rate of these transmitters sets the data acquisition rate of OLA. Laser pulses from both the low and high energy transmitters are directed onto a movable scanning mirror, which is co-aligned with the field of view of the receiver telescope limiting the effects of background solar radiation. Each pulse provides target range, azimuth, elevation, received intensity and a time-tag.[citation needed]
The sample-return system, called Touch-And-Go Sample Acquisition Mechanism (TAGSAM), consists of a sampler head with an articulated 3.35m (11.0ft) arm.[2][95] An on-board nitrogen source supports up to three separate sampling attempts to acquire at least 60g (2.1oz) of sample in all. The surface contact pads also collect fine-grained material.[citation needed]
Highlights of the TAGSAM instrument and technique include:
Relative approach velocity of 10cm/s (3.9in/s)[104]
Contact within 25m (82ft) of selected location
OCAMS documents sampling at 1Hz
Collect samples in less than five seconds, direct nitrogen (N2) annular jet fluidizes regolith, surface-contact pad captures surface sample
Verify bulk sample collection via spacecraft inertia change; surface sample by imaging sampler head
Sampler head stored in sample-return capsule and returned to Earth
Cooperation with JAXA
Hayabusa2 is a similar mission from JAXA to collect samples from near-Earth asteroid 162173 Ryugu. It arrived at the asteroid in June2018, left in November2019 after two successful sample collections, and returned to Earth in December2020. The recovery capsule of Hayabusa2 re-entered Earth atmosphere and landed in Australia, as planned, on 5December 2020. The sample contents were to be extensively analyzed, including water content, to provide clues on the initial formation of the asteroid. The main module of Hayabusa2 is performing a swing-by procedure to "push" it onward to its next destination, asteroid 1998KY26, by 2031. Because the two missions were similar and had overlapping timelines (OSIRIS-REx was still in the return phase), NASA and JAXA signed an agreement to collaborate on sample exchange and research.[105][106] The two teams visited each other, with representatives from JAXA visiting the OSIRIS-REx Science Operations Center at the University of Arizona, and members of the OSIRIS-REx team traveling to Japan to meet with the Hayabusa2 team.[107][108] The teams are sharing software, data, and techniques for analysis, and will eventually exchange portions of the samples that are returned to Earth.[109][110]
OSIRIS-REx II
OSIRIS-REx II was a 2012 mission concept to replicate the original spacecraft for a double mission, with the second vehicle collecting samples from the two moons of Mars, Phobos and Deimos. It was stated that this mission would be both the quickest and least expensive way to get samples from the moons. Mars I and II are now the aims of another mission, led by JAXA, called MMX, to be launched in 2024.[111][112][113]
Gallery
Narrated tour of Bennu's most prominent surface features, as seen by OSIRIS-REx
Effects of OSIRIS-REx sampling attempt on Bennu
Earth–Moon system during an engineering test (January 2018)
First images of asteroid Bennu (August 2018).
Asteroid Bennu from 330km (210mi) away (29 October 2018)
Earth-Moon (lower left) and asteroid Bennu (upper right) (December 2018)[114]
The Sample Return Capsule (SRC) with asteroid Bennu in the background (December 2019)
The "Nightingale" sample site pictured before and after the sampling maneuver.
↑ Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer
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Janus was a planned NASA mission that would have sent dual space probes to visit asteroids chosen prior to launch. The mission was part of NASA's SIMPLEx program and was expected to be launched in 2022 as a secondary payload on Falcon Heavy together with the Psyche spacecraft, but it was removed due to delays with Psyche. The mission budget was limited to US$55 million.
Daniella ("Dani") Mendoza DellaGiustina is a Mexican American planetary scientist and academic. She is the principal investigator for NASA's OSIRIS-APEX Mission to asteroid (99942) Apophis, Deputy Principal Investigator of NASA's OSIRIS-REx Asteroid Sample Return Mission, and assistant professor at the University of Arizona's Lunar and Planetary Laboratory.
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↑ "Science Team Meeting12". Instagram. OSIRIS-REx. 29 March 2017. Archived from the original on 26 December 2021. Retrieved 12 February 2020. This week we're hosting Science Team Meeting12 at @uarizona. More than 100members of @nasa's OSIRIS-REx team and @jaxajp's Hayabusa2 team are gathered in Tucson to exchange information, share ideas and plan ways the two #asteroid-bound missions can collaborate. #science
Launches are separated by dots ( • ), payloads by commas ( , ), multiple names for the same satellite by slashes ( / ). Cubesats are smaller. Crewed flights are underlined. Launch failures are marked with the † sign. Payloads deployed from other spacecraft are (enclosed in parentheses).
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