OSIRIS-Rex – Atlas V 411 (AV-067) – Canaveral SLC-41 – 08.09.2016 23:05 UTC

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https://www.asteroidmission.org/?latest-news=first-official-names-given-to-features-on-asteroid-bennu

FIRST OFFICIAL NAMES GIVEN TO FEATURES ON ASTEROID BENNU

March 6, 2020 - Asteroid Bennu's most prominent boulder, a rock chunk jutting out 71 ft (21.7 m) from the asteroid's southern hemisphere, finally has a name. The boulder – which is so large that it was initially detected from Earth – is officially designated Benben Saxum after the primordial hill that first arose from the dark waters in an ancient Egyptian creation myth.


This flat projection mosaic of asteroid Bennu shows the locations of the first 12 surface features to receive official names from the International Astronomical Union. The accepted names were proposed by NASA's OSIRIS-REx team members, who have been mapping the asteroid in detail over the last year. Bennu's surface features are named after birds and bird-like creatures in mythology, and the places associated with them. Credit: NASA/Goddard/University of Arizona

Benben Saxum and 11 other features on the asteroid are the first to receive official Bennu feature names approved by the International Astronomical Union (IAU), the internationally recognized authority for naming celestial bodies and their surface features. The accepted names were proposed by NASA's OSIRIS-REx team members, who have been mapping the asteroid in detail over the last year. The OSIRIS-REx spacecraft, NASA's first asteroid sample return mission, is currently visiting the asteroid and is scheduled to collect a sample from Bennu's surface this summer.

"Since arriving at the asteroid, the OSIRIS-REx team has become incredibly familiar with all of the geological features on Bennu," said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson. "These features are providing us with insight into Bennu's history, and their new names symbolize the essence of the mission – studying the past to both discover our origins and understand our future," said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson.

The approved Bennu surface feature names are listed below. Bennu's diverse terrain types – including regiones (broad geographic regions), craters, dorsa (ridges), fossae (grooves or trenches) and saxa (rocks and boulders) – will be named after birds and bird-like creatures in mythology, and the places associated with them.


Credit: NASA/Goddard/University of Arizona

Tlanuwa Regio is named for the giant birds who scattered the Earth with pieces of a serpent that turned into standing pillars of rocks in Cherokee mythology. Tlanuwa Regio is an area covered by large boulders in Bennu's southern hemisphere.


Credit: NASA/Goddard/University of Arizona

Benben Saxum is named for an ancient Egyptian mound that arose from the primordial waters Nu. In Egyptian mythology, the god Atum settled upon Benben to create the world after his flight over the waters in the form of the Bennu bird. Benben Saxum is the tallest boulder on Bennu.


Credit: NASA/Goddard/University of Arizona

Roc Saxum is named for the Roc, an enormous bird of prey in Arabian mythology of the Middle East. Roc Saxum is the largest boulder feature on Bennu.


Credit: NASA/Goddard/University of Arizona

Simurgh Saxum is named for the benevolent, mythological bird in Persian mythology. The Simurgh was said to possess all knowledge, and Simurgh Saxum defines the prime meridian on Bennu and is the basis for the asteroid's coordinate system.


Credit: NASA/Goddard/University of Arizona

Huginn Saxum and Muninn Saxum are adjacent boulders named for the two ravens, Huginn and Muninn, who accompany the god Odin in Norse mythology.


Credit: NASA/Goddard/University of Arizona

Ocypete Saxum is named for one of the Greek harpies, the half-maiden and half-bird personification of storm winds that would snatch and carry things away from Earth. Ocypete Saxum is located near the origin of the Jan. 19, 2019, particle ejection event on Bennu.


Credit: NASA/Goddard/University of Arizona

Strix Saxum is named for the Strix bird of ill-omen from Roman mythology. Strix Saxum is a large boulder flanking the OSIRIS-REx mission's backup sample collection site.


Credit: NASA/Goddard/University of Arizona

Amihan Saxum is named for the Tagalog (Philippines) mythological deity, who is depicted as a bird and was the first creature to inhabit the universe. This large, flat boulder appears to be partly buried and is located in Tlanuwa Regio, which has an unusually high concentration of large boulders.


Credit: NASA/Goddard/University of Arizona

Pouakai Saxum is named for the monstrous bird who kills and eat humans in Māori (Polynesia) mythology. Pouakai Saxum is a 55 ft (10.6 m)-wide boulder located in Bennu's southern hemisphere, slightly north of Benben Saxum.


Credit: NASA/Goddard/University of Arizona

Aetos Saxum is named for the childhood playmate of the supreme god Zeus, who was turned into an eagle by Hera in Greek mythology. Aetos Saxum is a conspicuously flat boulder, with a general wing-like shape located near Bennu's equator.


Credit: NASA/Goddard/University of Arizona

Gargoyle Saxum is named for the French dragon-like monster with wings, bird-like neck, and the ability to breathe fire. Gargoyle Saxum is a large prominent boulder near the mission's backup sample site that is one of the darkest objects on the surface.

NASA's Goddard Space Flight Center in Greenbelt, Maryland provides overall mission management, systems engineering, and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator, and the University of Arizona also leads the science team and the mission's science observation planning and data processing. Lockheed Martin Space in Denver built the spacecraft and is providing flight operations. Goddard and KinetX Aerospace are responsible for navigating 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 Science Mission Directorate in Washington.

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How OSIRIS-REx will Steer Itself to Sample an Asteroid

NASA Goddard

9 мар. 2020 г.

In late August, the OSIRIS-REx spacecraft will navigate to asteroid Bennu's surface for its first sample collection attempt. To do this, it will use an onboard image software known as Natural Feature Tracking (NFT) — a form of optical navigation that is completely autonomous. NFT guides the spacecraft by comparing an onboard image catalog with the real-time navigation images it takes during descent, looking for specific landmarks on Bennu's surface in order to orient itself. This navigation technique allows the spacecraft to accurately target small sites while dodging potential hazards.

https://www.youtube.com/embed/nfGJzjSGSM8 (2:08)

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https://www.asteroidmission.org/?latest-news=bennus-boulders-shine-as-beacons-for-nasas-osiris-rex

Bennu's Boulders Shine as Beacons for NASA's OSIRIS-REx

March 9, 2020 - This summer, the OSIRIS-REx spacecraft will undertake NASA's first-ever attempt to touch the surface of an asteroid, collect a sample of it, and safely back away. But since arriving at asteroid Bennu over a year ago, the mission team has been tackling an unexpected challenge: how to accomplish this feat at an asteroid whose surface is blanketed in building-sized boulders.


During the sample collection event, Natural Feature Tracking (NFT) will guide NASA's OSIRIS-REx spacecraft to asteroid Bennu's surface. The spacecraft takes real-time images of the asteroid's surface features as it descends, and then compares these images with an onboard image catalog. The spacecraft then uses these geographical markers to orient itself and accurately target the touchdown site. Credit: NASA/Goddard/University of Arizona

Using these hazardous boulders as signposts, the mission team developed a new precision navigation method to overcome the challenge.

The OSIRIS-REx team had originally planned to use a LIDAR system to navigate to Bennu's surface during the Touch-And-Go (TAG) sample collection event. LIDAR is similar to radar, but it uses laser pulses rather than radio waves to measure distance. The OSIRIS-REx Guidance, Navigation, and Control (GNC) LIDAR is designed to navigate the spacecraft to a relatively hazard-free surface. The mission had originally envisioned a touchdown site 164 ft (50 meters) in diameter, but the largest safe areas on Bennu are much smaller. The biggest site is just 52 ft (16 m) wide, or roughly 10% of the safe area envisioned. The team realized that they needed a more precise navigation technique that would allow the spacecraft to accurately target very small sites while dodging potential hazards.

In the face of this challenge, the OSIRIS-REx team switched to a new navigation method called Natural Feature Tracking (NFT). NFT provides more extensive navigation capabilities than LIDAR, and is key for executing what the team is calling "Bullseye TAG," which delivers the spacecraft to the much smaller sampling area. As an optical navigation technique, it requires the creation of a high-resolution image catalog onboard the spacecraft.

Earlier this year, the spacecraft made reconnaissance passes over the mission's primary and backup sample collection sites, designated Nightingale and Osprey, flying as close as 0.4 miles (625 m) over the surface. During these flyovers, the spacecraft collected images from different angles and lighting conditions to complete the NFT image catalog. The team uses this catalog to identify boulders and craters unique to the sample site region, and will upload this information to the spacecraft before the sample collection event. NFT autonomously guides the spacecraft to Bennu's surface by comparing the onboard image catalog with the real-time navigation images taken during descent. As the spacecraft descends to the surface, NFT updates its predicted point of contact depending on the spacecraft's position in relation to the landmarks.

On the ground, team members created "hazard maps" for both the Nightingale and Osprey sites to document all of the surface features that could potentially harm the spacecraft, like large rocks or steep slopes. The team used the image catalog in conjunction with data from the OSIRIS-REx Laser Altimeter (OLA) to create 3D maps that closely model Bennu's topography. As part of NFT, these maps document boulder heights and crater depths, and guide the spacecraft away from potential hazards while targeting a very small site. During descent, if the spacecraft predicts it will touch unsafe terrain, it will autonomously wave-off and back away from the surface. However, if it sees that the area is free of hazards, it will continue to descend and attempt to collect a sample.


During sample collection, Natural Feature Tracking (NFT) will guide NASA's OSIRIS-REx spacecraft to asteroid Bennu's surface. Hazard maps are also part of the NFT guidance system – they document boulder heights and crater depths, and guide the spacecraft away from potential hazards. Credit: NASA/Goddard/University of Arizona

NFT will be used in April to navigate the spacecraft during its first sample collection rehearsal. The operations team performed preliminary testing during the Orbital B mission phase in late 2019, and the results demonstrated that NFT works in real-life conditions as designed. NFT will also be used for navigation during the second rehearsal planned for June.

OSIRIS-REx's first sample collection attempt is scheduled for late August. The spacecraft will depart Bennu in 2021 and is scheduled to deliver the sample to Earth in September 2023.

NASA's Goddard Space Flight Center in Greenbelt, Maryland, provides overall mission management, systems engineering, and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator, and the University of Arizona also leads the science team and the mission's science observation planning and data processing. Lockheed Martin Space in Denver built the spacecraft and provides flight operations. Goddard and KinetX Aerospace are responsible for navigating 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 Science Mission Directorate in Washington.

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https://www.asteroidmission.org/20200303reconcwolfrock/

North East of Nightingale's Crater

This image shows a detailed view of several large boulders located near sample site Nightingale on asteroid Bennu. The sample site is west and south of these boulders (outside of the image frame). The image was taken by the PolyCam camera on NASA's OSIRIS-REx spacecraft on March 3 fr om a distance of 0.2 miles (0.3 km). The field of view is 15 ft (4.7 m). For reference, the oval-shaped boulder on the left side of the image is 8 ft (2.4 m) long, which is about the length of a horse. The image was obtained during the mission's Reconnaissance C phase. When it was taken, the spacecraft was over the northern hemisphere, pointing PolyCam north and to the east.

Date Taken: March 3, 2020

Instrument Used: OCAMS (PolyCam)

Credit: NASA/Goddard/University of Arizona

NASA's OSIRIS-REx‏ @OSIRISREx 21 мин. назад

Also, for some context — here's wh ere the image was taken in relation to the sample site.

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https://www.asteroidmission.org/20200303mtdoomedge/

Edge of Building-Sized Boulder

This image shows the edge of the building-sized boulder that is situated outside sample site Nightingale's crater on asteroid Bennu. The sample site is directly west of the boulder (outside of the image frame). The image was taken by the PolyCam camera on NASA's OSIRIS-REx spacecraft on March 3 from a distance of 0.2 miles (0.3 km). The field of view is 15 ft (4.7 m). For reference, the large fractured boulder in the upper right is 5.5 ft (1.7 m), which is about the length of a bicycle. The image was obtained during the mission's Reconnaissance C phase. When it was taken, the spacecraft was over the northern hemisphere, pointing PolyCam north and to the east.

Date Taken: March 3, 2020

Instrument Used: OCAMS (PolyCam)

Credit: NASA/Goddard/University of Arizona

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https://www.asteroidmission.org/20200303closestviewofnightingale/

Closest View Of Nightingale

This image shows sample site Nightingale itself, which is located high in asteroid Bennu's northern hemisphere. The targeted touchdown point is visible in the lower left quadrant, southwest of the rock in the center of the image. The image was taken by the PolyCam camera on NASA's OSIRIS-REx spacecraft on March 3 from a distance of 0.2 miles (0.3 km). The field of view is 13 ft (4 m). For reference, the rock in the center of the image is 2 ft (70 cm) long, which is about the length of a small ice chest. The image was obtained during the mission's Reconnaissance C phase. When it was taken, the spacecraft was over the northern hemisphere, pointing PolyCam north and to the east.

Date Taken: March 3, 2020

Instrument Used: OCAMS (PolyCam)

Credit: NASA/Goddard/University of Arizona

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https://www.asteroidmission.org/20200303threesisters/

Boulders in Nightingale Crater

This image shows three boulders near the center of the crater where sample site Nightingale is located on asteroid Bennu. The sample site itself is directly east of these rocks (outside of the image frame). The image was taken by the PolyCam camera on NASA's OSIRIS-REx spacecraft on March 3 from a distance of 0.2 miles (0.3 km). The field of view is 13 ft (4 m). For reference, the flat boulder (center right) is 5 ft (1.5 m) long, which is about the length of a pool cue. The image was obtained during the mission's Reconnaissance C phase. When it was taken, the spacecraft was over the northern hemisphere, pointing PolyCam north and to the east.

Date Taken: March 3, 2020

Instrument Used: OCAMS (PolyCam)

Credit: NASA/Goddard/University of Arizona

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https://www.asteroidmission.org/20200303northwesternrockcluster/

Rock Cluster in Nightingale Crater

This image shows a cluster of medium-sized rocks situated in the crater where sample site Nightingale is located on asteroid Bennu. The sample site itself is located southeast of these rocks (outside of the image frame). The image was taken by the PolyCam camera on NASA's OSIRIS-REx spacecraft on March 3 from a distance of 0.2 miles (0.3 km). The field of view is 13 ft (4 m). For reference, the bright rock in the lower right is 9 inches (24 cm) across, which is about the size of a small casserole dish. The image was obtained during the mission's Reconnaissance C phase. When it was taken, the spacecraft was over the northern hemisphere, pointing PolyCam north and to the east.

Date Taken: March 3, 2020

Instrument Used: OCAMS (PolyCam)

Credit: NASA/Goddard/University of Arizona

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https://www.asteroidmission.org/20200303pebblesincrevices/

Boulder Crevices Brimming with Pebbles

This image provides a detailed view of a large boulder that is located northwest of sample site Nightingale on asteroid Bennu. Fine-grained material is visible in the boulder's crevices and at its base. The image was taken by the PolyCam camera on NASA's OSIRIS-REx spacecraft on March 3 from a distance of 0.2 miles (0.3 km). The field of view is 11 ft (3.5 m). For reference, many of the pebbles resting on the boulder's surface are between 1 and 2 inches (2.6 and 5 cm) wide, or range from the size of a cherry tomato to the size of a lime. The image was obtained during the mission's Reconnaissance C phase. When it was taken, the spacecraft was over the northern hemisphere, pointing PolyCam north and to the west.

Date Taken: March 3, 2020

Instrument Used: OCAMS (PolyCam)

Credit: NASA/Goddard/University of Arizona

NASA's OSIRIS-REx ✔@OSIRISREx 9:44 PM - Mar 18, 2020

Here's the location of the image in relation to the Nightingale crater and sample site.

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https://www.asteroidmission.org/20200303blockrock/

Partially-Buried Boulder Near Nightingale

This image shows a partially-buried boulder with an almost square corner that is located northwest of sample site Nightingale on asteroid Bennu. Extremely fine-grained material is visible on the boulder's surface. The image was taken by the PolyCam camera on NASA's OSIRIS-REx spacecraft on March 3 from a distance of 0.2 miles (0.3 km). The field of view is 11 ft (3.5 m). For reference, the visible bottom edge of the square boulder is 9 ft (2.7 m) across, which is about the width of a parking space. The image was obtained during the mission's Reconnaissance C phase. When it was taken, the spacecraft was over the northern hemisphere, pointing PolyCam north and to the west.

Date Taken: March 3, 2020

Instrument Used: OCAMS (PolyCam)

Credit: NASA/Goddard/University of Arizona

NASA's OSIRIS-REx
✔@OSIRISREx 8:27 PM - Mar 19, 2020

This is the location of the image (upper far left) in relation to the Nightingale crater and sample site.

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https://www.asteroidmission.org/bennu_global_mosaic/

Bennu Global Mosaic

This global map of asteroid Bennu's surface is a mosaic of images collected by NASA's OSIRIS-REx spacecraft between Mar. 7 and Apr. 19, 2019. A total of 2,155 PolyCam images were stitched together and corrected to produce the mosaic. At 2 inches (5 cm) per pixel, this is the highest resolution at which a planetary body has been globally mapped. The spacecraft collected these images at distances ranging from 1.9 to 3.1 miles (3.1 to 5 km) above the asteroid's surface. This detailed view of Bennu was used by the mission team during their selection of the primary and backup sample collection sites – Nightingale and Osprey.

Full-sized versions of the mosaic are available for download here (mosaic only) and here (mosaic with coordinate system).

Date Taken: Apr. 19, 2019

Instrument Used: OCAMS (PolyCam)

Credit: NASA/Goddard/University of Arizona

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https://www.asteroidmission.org/20190329-northern-sample-site-candidate/

Backup Sample Site Osprey on Asteroid Bennu

This image shows the backup sample collection site, Osprey, on asteroid Bennu. The 71 ft (21.6 m) wide crater just north of Bennu's equator appears to contain fine-grained material and is relatively free of hazards to the spacecraft. Although it is significantly smaller than the OSIRIS-REx mission's original plans for a 164 ft (50 m) wide sampling region, Bennu's high density of boulders means the team must prepare to sample a markedly smaller area. The image was taken by the PolyCam camera on NASA's OSIRIS-REx spacecraft on March 29 from a distance of 2.2 miles (3.6 km). The field of view is 165 ft (50.3 m). For scale, the light-colored rock that looks like a spear tip in the crater is 17 ft (5.2 m) long, which is about the same length as a box truck. The image was obtained during Flyby 4B of the mission's Detailed Survey: Baseball Diamond phase. When the image was taken, the spacecraft was over the northern hemisphere, pointing PolyCam slightly south.

Date Taken: March 29, 2019

Instrument Used: OCAMS (PolyCam)

Credit: NASA/Goddard/University of Arizona

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https://www.asteroidmission.org/?latest-news=rehearsal-time-for-nasas-asteroid-sampling-spacecraft

REHEARSAL TIME FOR NASA'S ASTEROID SAMPLING SPACECRAFT

April 9, 2020 - In August, a robotic spacecraft will make NASA's first-ever attempt to descend to the surface of an asteroid, collect a sample, and ultimately bring it safely back to Earth. In order to achieve this challenging feat, the OSIRIS-REx mission team devised new techniques to operate in asteroid Bennu's microgravity environment – but they still need experience flying the spacecraft in close proximity to the asteroid in order to test them. So, before touching down at sample site Nightingale this summer, OSIRIS-REx will first rehearse the activities leading up to the event.


This artist's concept shows the trajectory and configuration of NASA's OSIRIS-REx spacecraft during Checkpoint rehearsal, which is the first time the mission will practice the initial steps for collecting a sample from asteroid Bennu. Credit: NASA/Goddard/University of Arizona

On Apr. 14, the mission will pursue its first practice run – officially known as "Checkpoint" rehearsal – which will also place the spacecraft the closest it's ever been to Bennu. This rehearsal is a chance for the OSIRIS-REx team and spacecraft to test the first steps of the robotic sample collection event.

During the full touchdown sequence, the spacecraft uses three separate thruster firings to make its way to the asteroid's surface. After an orbit departure burn, the spacecraft executes the Checkpoint maneuver at 410 ft (125 m) above Bennu, which adjusts the spacecraft's position and speed down toward the point of the third burn. This third maneuver, called "Matchpoint," occurs at approximately 164 ft (50 m) from the asteroid's surface and places the spacecraft on a trajectory that matches the rotation of Bennu as it further descends toward the targeted touchdown spot.

The Checkpoint rehearsal allows the team to practice navigating the spacecraft through both the orbit departure and Checkpoint maneuvers, and ensures that the spacecraft's imaging, navigation and ranging systems operate as expected during the first part of the descent sequence. Checkpoint rehearsal also gives the team a chance to confirm that OSIRIS-REx's Natural Feature Tracking (NFT) guidance system accurately updates the spacecraft's position and velocity relative to Bennu as it descends towards the surface.

Checkpoint rehearsal, a four-hour event, begins with the spacecraft leaving its safe-home orbit, 0.6 miles (1 km) above the asteroid. The spacecraft then extends its robotic sampling arm – the Touch-And-Go Sample Acquisition Mechanism (TAGSAM) – from its folded, parked position out to the sample collection configuration. Immediately following, the spacecraft slews, or rotates, into position to begin collecting navigation images for NFT guidance. NFT allows the spacecraft to autonomously guide itself to Bennu's surface by comparing an onboard image catalog with the real-time navigation images taken during descent. As the spacecraft descends to the surface, the NFT system updates the spacecraft's predicted point of contact depending on OSIRIS-REx's position in relation to Bennu's landmarks.

Before reaching the 410-ft (125-m) Checkpoint altitude, the spacecraft's solar arrays move into a "Y-wing" configuration that safely positions them away from the asteroid's surface. This configuration also places the spacecraft's center of gravity directly over the TAGSAM collector head, which is the only part of the spacecraft that will contact Bennu's surface during the sample collection event.

In the midst of these activities, the spacecraft continues capturing images of Bennu's surface for the NFT navigation system. The spacecraft will then perform the Checkpoint burn and descend toward Bennu's surface for another nine minutes, placing the spacecraft around 243 ft (75 m) from the asteroid – the closest it has ever been.

Upon reaching this targeted point, the spacecraft will execute a back-away burn, then return its solar arrays to their original position and reconfigure the TAGSAM arm back to the parked position. Once the mission team determines that the spacecraft successfully completed the entire rehearsal sequence, they will command the spacecraft to return to its safe-home orbit around Bennu.

Following the Checkpoint rehearsal, the team will verify the flight system's performance during the descent, and that the Checkpoint burn accurately adjusted the descent trajectory for the subsequent Matchpoint burn.

The mission team has maximized remote work over the last month of preparations for the checkpoint rehearsal, as part of the COVID-19 response. On the day of rehearsal, a limited number of personnel will command the spacecraft from Lockheed Martin Space's facility, taking appropriate safety precautions, while the rest of the team performs their roles remotely.

The mission is scheduled to perform a second rehearsal on Jun. 23, taking the spacecraft through the Matchpoint burn and down to an approximate altitude of 82 ft (25 m). OSIRIS-REx's first sample collection attempt is scheduled for Aug. 25.

NASA's Goddard Space Flight Center in Greenbelt, Maryland provides overall mission management, systems engineering, and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator, and the University of Arizona also leads the science team and the mission's science observation planning and data processing. Lockheed Martin Space in Denver built the spacecraft and is providing flight operations. Goddard and KinetX Aerospace are responsible for navigating 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 Science Mission Directorate in Washington.

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 NASA's OSIRIS-REx‏ @OSIRISREx 10 апр.

My first rehearsal for the sample collection event is on Tuesday I won't actually touch Bennu, but I'll practice the first steps of the sample collection sequence. Join me on the four-hour-long excursion!

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 NASA's OSIRIS-REx‏ @OSIRISREx 1 ч. назад

Tune in tomorrow at 2:45 pm EDT to follow along with the Checkpoint rehearsal activities!

Here's what we'll be doing

Download the Checkpoint rehearsal poster here: https://bit.ly/2RBNlF0

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 NASA's OSIRIS-REx‏ @OSIRISREx 29 мин. назад

I'm ~140 million miles (~230 million km) from Earth, and it takes 13 minutes for any message to travel between us, which means that my team on Earth sees events 13 minutes after they happen here at Bennu. It also means that live commanding of flight activities isn't possible.




29 мин. назад

T-7 minutes to orbit departure for the first rehearsal of my Touch-And-Go (TAG) sample collection event. Who's ready?

(0:49)

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 NASA's OSIRIS-REx @OSIRISREx 57 мин. назад

I'll be transmitting data at a rate of 40 bits/sec - 28x less than the data volume for a SMS txt message! So it won't include images or science data, but my team can see how I'm doing. After the rehearsal, I'll transmit all of the data from the event via my High Gain Antenna

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NASA's OSIRIS-REx @OSIRISREx 57 мин. назад

This is a 4 hour event, and I'm moving at an average speed of approximately 0.2 mph (0.3 kph) relative to Bennu. (Or about the speed of a tortoise )
I'll provide updates as each event of the rehearsal sequence occurs.

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 NASA's OSIRIS-REx‏ @OSIRISREx 21 мин. назад

It's happening! The team just received confirmation that I've fired the Attitude Control System (ACS) thrusters to leave my 0.6-mile (1-km) safe-home orbit.

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 NASA's OSIRIS-REx‏ @OSIRISREx 6 мин. назад

The team just received confirmation that the sampling arm - called the TAGSAM (Touch-and-Go Sample Acquisition Mechanism) - is now extending to the sampling position
This is a slow and steady process that takes about 30 minutes.

(0:08)