OSIRIS-REx news - 2019

2019-12-12

After a challenging process, Nightingale was officially chosen as OSIRIS-REx's final site to collect a sample of asteroid Bennu.

The Canadian OSIRIS-REx Laser Altimeter, or OLA, scanned the asteroid's surface to create high-resolution 3D maps that were crucial to help mission scientists select the best sample site. As the mission progressed, scientists discovered that Bennu's surface was much more rugged than initially expected. Without OLA data, the selection of a sample site would have been even more complex. The Canadian instrument produced the most detailed three-dimensional measurements of a celestial body, vital for such a challenging mission.

In August, Sandpiper, Osprey, Kingfisher, and Nightingale were identified as the four candidate sample sites. NASA's OSIRIS-REx spacecraft performed a series of flyovers to provide the science team with high-resolution data and imagery of each site. Detailed images of the boulders, craters and other geological features were produced to help mission scientists select the safest and most scientifically interesting location. Nightingale was then chosen as the primary site, and Osprey as the back-up option.

The Nightingale site is located in a large crater with several sampling regions and holds the greatest amount of fine-grained material, which is essential to collect enough sample to ensure mission success. Moreover, Nightingale's regolith (the layer of loose material covering solid rock) is relatively smooth, well preserved and freshly exposed. This means the site would likely provide a pristine sample of the asteroid, giving the team insight into Bennu's history. But collecting this sample will be a tricky endeavour as the OSIRIS-REx spacecraft will have to get around a boulder the size of a building that is located on the crater's eastern rim.

OLA will continue to work in tandem with other instruments on the spacecraft to gather crucial data about the primary and backup sample sites. Sample collection is scheduled for summer 2020, and the sample will return to Earth in September 2023. Thanks to the Canadian Space Agency's contribution to the mission, Canada will receive a portion of the returned sample.

2019-08-29

A made-in-Canada laser aboard NASA's OSIRIS-REx spacecraft has produced high-resolution topographic maps of the four locations on asteroid Bennu that mission scientists have identified as candidates for sample collection.

The OSIRIS-REx Laser Altimeter, or OLA, is equipped with two lasers that scanned the asteroid's surface to produce detailed images of the boulders, craters and other geological features at each of the four sites. These maps will be crucial in helping mission scientists select the safest and most scientifically interesting of the approximately 10-metre-wide candidates – known as Nightingale, Kingfisher, Osprey, and Sandpiper.

OLA's high-resolution results follow the activation of the instrument's low-energy laser transmitter (LELT) at the beginning of July 2019. The LELT is designed to fire 10,000 light pulses per second at the asteroid, and operates at a range of less than 1 km above Bennu's surface.

In previous mission phases, OLA's high-energy laser transmitter (HELT) – firing 100 pulses per second from greater distances – collected data that enabled the creation of the first 3D lidar map of the asteroid in April.

By June, OLA's HELT had collected about 9 million additional measurements to complete coverage of the entire asteroid, compiling the first global map of asteroid Bennu's topography.

Mission scientists anticipate that high volumes of data collected by OLA's LELT – in the order of several billion measurements – will enable the creation of a new, higher-resolution global map, featuring one data point per 7 centimetres and offering an unprecedented level of detail over Bennu's entire surface.

High-resolution maps of the four potential sample sites, like that of the Sandpiper site below, will allow OSIRIS-REx scientists to:

• assess the safety and accessibility of each region
• locate landmarks that will help the spacecraft navigate during sample collection
• identify areas of fine-grained material compatible with OSIRIS-REx's sampling device

OLA's LELT will continue to work in tandem with other instruments on the spacecraft to gather crucial data about the surface of the asteroid. A primary and a backup site will be announced in December 2019, and the spacecraft is scheduled to begin rehearsing sampling manoeuvres in early 2020.

For more updates on the OSIRIS-REx mission, follow the Canadian Space Agency on social media.

2019-04-04

This colourful new glimpse of asteroid Bennu is the first 3D lidar map created since the OSIRIS-REx spacecraft's arrival at the asteroid in December 2018.

The three-dimensional shape model is based on data gathered by the Canadian Space Agency's OSIRIS-REx Laser Altimeter (OLA) instrument.

To create the image, over 11 million laser pulses were fired and captured by OLA between February 12 and 27 as OSIRIS-REx flew less than 2 kilometres from the asteroid's rocky surface.

The colours represent the distance from the centre of Bennu: dark blue areas lie approximately 60 metres lower than peaks indicated in red. Some parts of the asteroid have not yet been measured, which creates gaps in the image.

Throughout 2019, OLA will take nearly a billion more measurements to complete the first-ever high-resolution 3D lidar map of a near-Earth asteroid. Data collected by the Canadian-contributed technology will be essential in identifying a suitable sample site.