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Where is the OSIRIS-REx Spacecraft right now?

The app above shows the trajectory of the OSIRIS-REx Spacecraft and where it is right now. You can also wind the animation backwards in time to watch its launch and its flyby of the Earth before reaching the asteroid Bennu in 2018, and returning samples back to earth in 2023.

19th March 2018 - Mysterious plumes of particles coming from Asteroid Bennu

Plumes from Asteroid Bennu

This view of asteroid Bennu ejecting particles from its surface on January 19 was created by combining two images taken on board NASA’s OSIRIS-REx spacecraft. Other image processing techniques were also applied, such as cropping and adjusting the brightness and contrast of each image. Credits: NASA/Goddard/University of Arizona/Lockheed Martin

In January and February the OSIRIS Team reported detecting particles which were orbiting or surrounding the asteroid Bennu and were studying them in order to determine the nature of these objects. They have now announced that these particles are being ejected from the surface of the asteroid in plumes.

To say that this was unexpected is an understatement. On objects like comets which contain ice and other volatile compounds which can turn to gas as they approach the Sun and get warmed, out-gassing is expected which can cause particles to be ejected from the surface. However asteroids which are thought to have circled the Sun at an (approximately) constant distance would, if they originally contained such volatile compounds, have been expected to finish out-gassing millions of years ago.

These particle plumes were first detected (Jan 6) and then 11 bursts in the next two months. This happens to coincide with the asteroids perihelion (closest point to the Sun) when the asteroid is at it's warmest, giving speculation that volatile substances under the surface are causing the plumes.

The detected particles range in size from about a centimetre to tens of centimetres across with speeds of up to several miles per hour. This is enough that some particles are ejected into space never to return, but others fall back or go in orbit for a while before falling back onto the asteroid.

The OSIRIS team are trying to analyse (and get more) data before speculating themselves as to what is causing the plumes.

Boulder Strewn surface of Asteroid Bennu

This image shows a view across asteroid Bennu’s southern hemisphere and into space, and it demonstrates the number and distribution of boulders across Bennu’s surface. The image was obtained on Mar. 7 by the PolyCam camera on NASA’s OSIRIS-REx spacecraft from a distance of about 3 miles (5 km). The large, light-colored boulder just below the center of the image is about 24 feet (7.4 meters) wide, which is roughly half the width of a basketball court. Credits: NASA/Goddard/University of Arizona

As well as plumes of particles to contend with, the fact that the surface of Bennu is boulder strewn rather than smaller particles such as dust or gravel, makes the task of obtaining a sample from the surface much harder. The team need to find a target area comprised of finer particles to sample and in a clear area without large boulders that might hamper the descent or ascent.

Articles: NASA, Spaceflightnow


31st December 2018 - OSIRIS enters orbit - and the record books.

At 2:43 p.m. EST on December 31, NASA’s OSIRIS-REx spacecraft, 70 million miles (110 million kilometres) away, carried out a single, eight-second burn of its thrusters – and broke a space exploration record. The spacecraft entered into orbit around the asteroid Bennu, and made Bennu the smallest object ever to be orbited by a spacecraft.

Up until now OSIRIS has accompanied Bennu in it's orbit about the Sun, but has not been in orbit around Bennu. This is because Bennu is quite small (60-80 million metric tonnes) and has a very weak gravitation pull. OSIRIS has now moved be 1.75 kilometres from Bennu's Centre (about 1.5km above the surface) and completing each orbit in around 62 hours. That's an orbital speed of about 5cm per second. Article.

10th December 2018 - Asteroid Bennu has been affected by water

Asteroid Bennu

This mosaic image of asteroid Bennu is composed of 12 PolyCam images collected on Dec. 2 by the OSIRIS-REx spacecraft from a range of 15 miles (24 km).Credits: NASA/Goddard/University of Arizona

OSIRIS-Rex Spectrometers have detected that hydroxyls (or molecules containing Oxygen and Hydrogen) are distributed within the "clays" of asteroid Bennu. This indicates that the rocks of Bennu were at some stage affected by water. Article.

14th November 2018 - OSIRIS-REx limbers up it's limbs in preparation for contact.

On Nov. 14, NASA’s OSIRIS-REx spacecraft stretched out its robotic sampling arm for the first time in space. The arm, more formally known as the Touch-and-Go Sample Acquisition Mechanism (TAGSAM), is key to the spacecraft achieving the primary goal of the mission: returning a sample from asteroid Bennu in 2023. Article.

The mechanism works as shown here:

6th November 2018 - An all round view of Bennu

Credit: NASA/Goddard/University of Arizona

OSIRIS-REx views Bennu as it spin over a 4 hour 11 minute period. Article.

29th October 2018 - OSIRIS-REx gets a good view of Bennu

Bennu from 205 miles

Credit: NASA/Goddard/University of Arizona.

Bennu is imaged from 205 miles away and a super resolution image is made by combining 8 low res images. Article.

1st October 2018 - OSIRIS-REx executed first approach manoeuvre

NASA’s OSIRIS-REx spacecraft executed its first Asteroid Approach Maneuver (AAM-1) today putting it on course for its scheduled arrival at the asteroid Bennu in December. The spacecraft’s main engine thrusters fired in a braking maneuver designed to slow the spacecraft’s speed relative to Bennu from approximately 1,100 mph (491 m/sec) to 313 mph (140 m/sec). The mission team will continue to examine telemetry and tracking data as they become available and will have more information on the results of the maneuver over the next week.

During the next six weeks, the OSIRIS-REx spacecraft will continue executing the series of asteroid approach maneuvers designed to fly the spacecraft through a precise corridor during its final slow approach to Bennu. The last of these, AAM-4, scheduled for Nov. 12, will adjust the spacecraft’s trajectory to arrive at a position 12 miles (20 km) from Bennu on Dec. 3. After arrival, the spacecraft will initiate asteroid proximity operations by performing a series of fly-bys over Bennu’s poles and equator. Article

July 2018 - Successful Second Deep Space Maneuver for OSIRIS-REx Confirmed

New tracking data confirms that NASA’s OSIRIS-REx spacecraft successfully completed its second Deep Space Maneuver (DSM-2) on June 28. The DSM-2 burn, which employed the spacecraft’s Trajectory Correction Maneuver (TCM) thruster set, resulted in a 37 miles per hour (16.7 meters per second) change in the vehicle’s velocity and consumed 28.2 pounds (12.8 kilograms) of fuel.

DSM-2 was OSIRIS-REx’s last deep space maneuver of its outbound cruise to Bennu. The next engine burn, Asteroid Approach Maneuver 1 (AAM-1), is scheduled for early October. AAM-1 is a major braking maneuver designed to slow the spacecraft’s speed from approximately 1,130 to 320 miles per hour (506.2 to 144.4 meters per second) relative to Bennu and is the first of four asteroid approach maneuvers scheduled in order to accomplish arrival on 3rd December 2018. Article.

OSIRIS-REx launched on 8th September 2016

OSIRIS-REx Spacecraft (Artists Impression)


This mission could help to save the world... quite literally! Bennu is a 500 meter wide asteroid that crosses Earth's orbit and has a low probability (about 0.04%) of hitting the earth in the next 200 years. This mission allows this asteroid to be studied in great detail and will return samples of rock to Earth allowing better analysis than has ever been possible before. It will also allow a more accurate track of the asteroid to be determined so that we will have a better estimate of the chances of impact. Also knowing its structure will (hopefully) allow scientists to develop ways of changing its (or any similar objects) orbit to protect the Earth if necessary.

Here as some videos that explain this exciting mission:

OSIRIS-REx Launch Video (8 September 2016)


Pre-launch Briefing


Phase name


Start time


Launch on an EELV from Cape Canaveral on an Earth-escape trajectory

8th Sept. 2016

Outbound cruise

Perform deep space maneuver; Earth flyby & gravity assist; instrument calibration & checkout

Oct. 2016


Perform braking maneuvers; survey the Bennu orbital environment for natural satellites; collect the first resolved images

Aug. 2018

Preliminary survey

Estimate the mass of Bennu; refine shape and spin state models

Nov. 2018

Orbital A

Demonstrate orbital flight; transition to landmark-based optical navigation

Dec. 2018

Detailed survey

Spectrally map the entire Bennu surface; collect images and lidar data for global shape and spin state models; search for dust plumes

Jan. 2019

Orbital B

Collect lidar and radiometric data for high resolution topographic map and gravity model; observe candidate sampling sites and down-select for reconnaissance

Mar. 2019


Conduct sorties for closer look at up to 4 candidate sampling sites and select 1

May 2019

TAG rehearsal

Systematically and deliberately practice steps of sample collection sequence

Aug. 2019

Sample collection

Collect >60g (Level 2 requirement) of pristine bulk regolith and 26 cm2 of surface material, and stow it in the SRC (Sample Return Capsule)

Sept. 2019

Quiescent operations

Remain in Bennu's heliocentric orbit; monitor spacecraft health

Oct. 2019

Return Cruise

Transport the sample back to the vicinity of the Earth

Mar. 2021

Earth Return & Recovery

Get the sample safely to the ground and to the curation facility in late September 2023

Sept. 2023


More Information:

OSIRIS-Rex on Earth Observation Portal Site
OSIRIS-REx Wikipedia