World News – UA – Secrets of Asteroid Bennu Unlocked by NASA’s OSIRIS-REx Before Historic Heist


Surface level view of OSIRIS-REx at the Nightingale example site, with parking for comparison Credit: NASA / Goddard / CI Lab / University of Arizona

NASA’s first asteroid sample return mission now knows a lot more about the material it will collect in a few weeks In a special collection of six papers published yesterday (October 8, 2020) in the journals Science and Science Advances, OSIRIS-REx mission scientists present new findings on the surface material, geological features and dynamic history of asteroid Bennu They also suspect that Bennu’s delivered sample may be unlike any other what we have in the meteorite collection on Earth

These findings complement the scientific requirements for collecting samples from the OSIRIS-REx mission and offer insight into Bennu’s sample that scientists will study for generations to come

Now, thanks to laser altimetry data and high-resolution images from OSIRIS-REx, we can take a tour of Bennu’s remarkable terrain Credit: NASA’s Goddard Space Flight Center

One of the documents, led by Amy Simon of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, shows that carbonaceous organic matter is widespread on the asteroid’s surface, including at the sampling site principal of the mission, Nightingale, where OSIRIS -REx will make its first attempt at sampling on October 20 These results indicate that hydrated minerals and organic matter will likely be present in the collected sample

This organic material may contain carbon in a form often found in biology or in compounds associated with biology Scientists are planning detailed experiments on these organic molecules and expect the returned sample to help respond to complex questions about the origins of water and life on Earth

« The abundance of carbonaceous material is a major scientific triumph for the mission We are now optimistic about the collection and return of a sample containing organic matter – a central objective of the OSIRIS-REx mission », said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona at Tucson

In the fall of 2019, NASA’s OSIRIS-REx spacecraft captured this image, which shows one of the rocks of the asteroid Bennu with a shiny vein that appears to be made of carbonate The image in the circle (bottom right) shows a focused view of the vein Credit: NASA / Goddard / University of Arizona

The authors of the special collection also determined that carbonate minerals were some of the geological features of the asteroid Carbonate minerals often precipitate from hydrothermal systems containing both water and carbon dioxide. many of Bennu’s rocks have shiny veins that appear to be made of carbonate – some of which are located near Nightingale Crater, meaning carbonates could be present in the returned sample

The study of the carbonates found on Bennu was conducted by Hannah Kaplan, of Goddard These findings allowed scientists to theorize that Bennu’s parent asteroid likely had an extensive hydrothermal system, in which water interacted with and weathered the rock on Bennu’s parent body Although the parent body was destroyed a long time ago, we see evidence of what this watery asteroid once looked like here – in its remaining fragments that make up Bennu Some of those carbonate veins in the Bennu rocks measure up to a few feet long and several inches thick, confirming that an asteroid-scale hydrothermal water system was present on Bennu’s parent body

Scientists have made another striking discovery at the Nightingale site: Its regolith was only recently exposed to the harsh space environment, which means the mission will collect and return some of the purest materials in the world. asteroid Nightingale is part of a population of young spectrally red craters identified in a study conducted by Dani DellaGiustina at the University of Arizona Bennu’s « colors » (variations in the slope of the spectrum of visible wavelengths) are many more diverse than originally expected This diversity results from a combination of different materials inherited from Bennu’s parent body and different durations of exposure to the space environment

The findings in this article are a major milestone in an ongoing debate in the planetary scientific community – how primitive asteroids like Bennu change spectrally when exposed to « spatial aging » processes, such as bombardment by Cosmic Rays and the Solar Wind While Bennu appears quite black to the naked eye, the authors illustrate the diversity of Bennu’s surface using false-color renderings of multispectral data collected by the MapCam camera.The freshest material on Bennu, such as the one found at the Nightingale site, is spectrally redder than average and therefore appears red in these images.The surface material turns bright blue when exposed to weathering for an intervening period While the surface material continues to withstand long periods of time, it eventually brightens at all wavelengths, becoming a less intense blue – Bennu’s average spectral color

The article by DellaGiustina et al also distinguishes two main types of rocks on Bennu’s surface: dark and rough and (less frequently) glossy and smooth.The different types may have formed at different depths in the parent asteroid by Bennu

Not only do the types of boulders differ visually, they also have their own unique physical properties The article led by Ben Rozitis of the Open University in the UK shows that dark rocks are weaker and more porous, so that shiny rocks are stronger and less porous The shiny boulders also harbor the carbonates identified by Kaplan and his team, suggesting that precipitation of carbonate minerals in cracks and pore spaces may be responsible for their increased strength

However, both types of boulders are weaker than scientists believed Rozitis and his colleagues suspect Bennu’s dark boulders (the weaker, more porous, and more common type) would not survive the trip. in the earth’s atmosphere It is therefore likely that the returned samples from the asteroid Bennu will be a missing link for scientists, as this type of material is currently not represented in meteorite collections

Bennu is a diamond-shaped pile of rubble floating in space, but there is more than you see Data obtained by the OSIRIS-REx laser altimeter (OLA) – a scientific instrument provided by the Canadian Space Agency – allowed the mission team to develop a 3D digital terrain model of the asteroid which, at a resolution of 20cm, is unprecedented in detail and precision In this article, directed by Michael Daly of York University, scientists explain how detailed analysis of the asteroid’s shape revealed ridge-shaped mounds on Bennu that stretch from pole to pole, but are sufficiently large subtle to be easily missed by humans eye Their presence was previously suggested, but their pole-to-pole extent only became clear when the northern and southern hemispheres were separated in the OLA data for comparison.

The digital terrain model also shows that Bennu’s northern and southern hemispheres have different shapes.The southern hemisphere appears to be smoother and rounder, which scientists say is the result of loose material trapped by the many large rocks in the region

NASA’s OSIRIS-REx mission created these images using false-color red-green-blue (RGB) composites of asteroid Bennu 2D map and spacecraft images have been overlaid on a shape model of the asteroid to create these false color composites In these composites, spectrally average and bluer than average, the terrain appears blue, surfaces redder than average appear red.The bright green areas correspond to instances of a mineral pyroxene, which probably originated from another asteroid, Vesta Black areas near the poles indicate no data Credit: NASA / Goddard / University of Arizona

Another special collection article, edited by Daniel Scheeres of the University of Colorado at Boulder, examines Bennu’s gravity field, which was determined by tracking the trajectories of the OSIRIS-REx spacecraft and the particles that are naturally ejected from Bennu surface The use of particles as gravity probes is fortuitous Before the discovery of particle ejection on Bennu in 2019, the team was concerned with mapping the gravity field to the required accuracy using only tracking data from the spacecraft The natural supply of dozens of mini gravity probes allowed the team to far exceed their requirements and gain unprecedented insight into the asteroid’s interior.

The reconstructed gravity field shows Bennu’s interior is not uniform Instead, there are pockets of higher and lower density material inside the asteroid It’s like s ‘there was a void in its center, in which you could fit a few football pitches In addition, the bulge at Bennu’s equator is under-dense, suggesting that Bennu’s rotation is smoothing out this material

The six publications in the special collection use global and local datasets collected by the OSIRIS-REx spacecraft from February to October 2019 The special collection emphasizes that sample return missions like OSIRIS-REx are essential for fully understand the history and evolution of our solar system

The mission is less than two weeks away from achieving its biggest goal of collecting a piece of a virgin, hydrated, carbon-rich asteroid OSIRIS-REx will leave Bennu in 2021 and deliver the sample to Earth on the 24th. September 2023

« The weak rocks of the asteroid (101955) Bennu and the thermally anomalous equator » by B Rozitis, AJ Ryan2, JP Emery, PR Christensen, VE Hamilton, A A Simon, DC Reuter, M Al Asad, RL Ballouz, JL Bandfield, OS Barnouin, C UNE Bennett, M ​​Bernacki, KN Burke, S Cambioni, BE Clark, M g Daly, M Delbo, DN DellaGiustina, CM Ancien, R ré Hanna, CW Haberle, ES Howell, DR Golish, ER Jawin, HH Kaplan, LF Lim, JL Molaro, D Pino Munoz, MC Nolan, B Rizk, M UNE Siegler, HCM Procurator, KJ Walsh and DS Lauretta, October 8, 2020, Science AdvancesDOI: 101126 / sciadvabc3699

« Hemispherical Differences in Asteroid Shape and Topography (101955) Bennu » By M g Daly, OS Barnouin, J A Seabrook, J Roberts, C Dickinson, KJ Walsh, ER Jawin, EE Palmer, R Gaskell , J Weirich, T Haltigin, D Gaudreau, C Brunet, G Cunningham, P Michel, Y Zhang, RL Ballouz, G Neumann, ME Perry, L Philpott, MM Al Asad, CL Johnson, C ré Adam, JM Leonard, JL Geeraert , K Getzandanner, MC Nolan, RT Daly, EB Bierhaus, E Mazarico, B Rozitis, AJ Ryan, DN Dellaguistina, B Rizk, HCM Procurator, HL Enos and DS Lauretta, October 8, 2020, Science AdvancesDOI: 101126 / sciadvabd3649

« Heterogeneous mass distribution of the rubble-pile asteroid (101955) Bennu » by DJ Scheeres, AS Français, P Tricarico, SR Chesley, Y Takahashi, D Farnocchia, JW McMahon, DN Brack, AB Davis, RL Ballouz, ER Jawin, B Rozitis, JP Emery, un J Ryan, RS Parc, BP Rush, N Mastrodemos, BM Kennedy, J Bellerose, DP Lubey, D Velez, A T Vaughan, JM Leonard, J Geeraert, B Page, P Antreasian, E Mazarico, K Getzandanner, D Rowlands, MC Moreau, J Petit, DE Highsmith, S Goossens, EE Palmer, JR Weirich, RW Gaskell, OS Barnouin, M g Daly, J UNE Seabrook, MM Al Asad, LC Philpott, CL Johnson, CM Hartzell, VE Hamilton, P Michel, KJ Walsh, MC Nolan and DS Lauretta, October 8, 2020, Science AdvancesDOI: 101126 / sciadvabc3350

« Visiting a once watery asteroid and how tongue ringing can treat tinnitus » by Sarah Crespi and Paul Voosen, October 8, 2020, ScienceDOI: 101126 / scienceabf1551

« NASA mission is about to capture carbon-rich dust from an ancient aquatic world » by By Paul Voosen, October 8, 2020, ScienceDOI: 101126 / scienceabf1722

NASA’s Goddard Space Flight Center in Greenbelt, Maryland provides overall mission management, systems engineering, and security and mission assurance for OSIRIS-REx Dante Lauretta, of the The University of Arizona, Tucson is the principal investigator, and the University of Arizona is also leading the science team as well as planning scientific observation and data processing. Lockheed Martin Space in Denver built the spacecraft and is providing flight operations Goddard and KinetX Aerospace are responsible for navigation in the OSIRIS-REx spacecraft OSIRIS-REx is the third mission in NASA’s New Frontiers program, which is managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Directorate of Scientific Missions in Washington

Ideally, samples should be kept off-plan and researchers should conduct their examination in the space station, as the presence of carbon and water indicates the possibility of ancient life forms that may not exist. benign

We also need to develop technologies that can deeply scrutinize a planet’s interios when we undertake such missions without having to depend on the planet’s cooperation to provide a constant flow of material.We should also be able to obtain samples without having to land on the planetary object All these technologies are anyway necessary for the third rock of the Sun on which we exist! Earthquake Science may require these to be available so that we can predict future earthquakes Surface-only monitoring activity will provide limited data and information

As the samples from Porus are unlikely to survive re-entry to Earth, these samples and all other samples should be examined and researched in the space station. Suggestions come from a risk management perspective

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News from the world – UA – Secrets of Asteroid Bennu unlocked by NASA’s OSIRIS-REx before historic heist


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