2019-06-01_All_About_Space

Mission to Bennu

Timeline of

OSIRIS-REx

at Bennu

Bennu was unexplored and

underappreciated before NASA’s

OSIRIS-REx arrived. No one even

knew what it looked like, and it was

merely referred to as 1999 RQ36!

Now the finely tuned machine of

instruments will map the entire

asteroid and collect at least 60

grams (2.1 ounces) of its surface to

bring back to Earth for analysis. This

mission began on 8 September 2016

when the spacecraft was launched

aboard an Atlas V rocket from Cape

Canaveral, Florida, United States.

The OSIRIS-REx spacecraft

includes the best cameras, altimeters

and spectrometers that NASA could

offer during construction. There are

three cameras in the OSIRIS-REx

Camera Suite (OCAMS): PolyCam,

MapCam and SamCam. The OCAMS

will be fundamental in mapping

Bennu’s surface and recording the

touch-and-go manoeuvre. The

LaserAltimeter(OLA)willuse

lasers to measure the distance

from the asteroid for topographic

measurements. The Thermal

Emission Spectrometer (OTES),

Visible and Infrared Spectrometer

(OVIRS) and Regolith X-ray Imaging

Spectrometer (REXIS) will identify

the minerals present in different

wavelengths, and determine the

elements present on Bennu's surface.

The spacecraft also has two

instruments that will orchestrate

the landing, sample collection

and return of the carbonaceous

asteroid. The Touch-And-Go Sample

Acquisition Mechanism (TAGSAM)

isasampleheadfittedatthe

end of an articulated arm. The

Sample Return Capsule (SRC) is an

aeroshellcontainerthatwillsurvive

the descent through the Earth’s

atmosphere to keep the sample safe

forthescientists–oncetheyfindit!

At the beginning of December

2018 OSIRIS-REx began its long-

awaited approach to the asteroid,

defining its shape and orbit. During

NewYearEvecelebrationsonEarth

OSIRIS-REx entered orbit around the

asteroid, sitting at a distance of just

1.4 kilometres (0.9 miles) away.

Bennu’s facts and stats

© NASA

Bennu is named after

the Egyptian deity that is

linked to the Sun, creation and

rebirth,usuallydepictedasa

grey heron.

7,000

B-type asteroids, the

category of Bennu, could

contain life-forming

compounds that led to

life on Earth.

Bennu was chosen out of over

7,000 known NEOs to be

the subject of OSIRIS-REx’s

investigation.

— Date: 8 September 2016

Activity: Launch from Cape

Canaveral, Florida, United

States, on an Atlas V 411 rocket.

Date: 3 December 2018

Activity: OSIRIS-REx arrives at

asteroid Bennu, beginning the

two-year survey.

Date: 4 July 2020

Activity: The spacecraft

will make its descent to the

asteroid; its main aim is to

collect a sample of regolith.

Date: 3 March 2021

Activity: It will be time to call

an end to the visit and OSIRIS-

REx will depart Bennu and head

back to Earth.

— Date: 24 September 2023

Activity: The spacecraft will

jettison the sample return

capsule, and after reentry it will

deploy a parachute, bringing

the capsule in for a soft landing

in the Utah desert.

Bennu’s close encounters to

Earth give it a high probability

of impacting Earth in the late

22nd century.

OSIRIS-REx will help scientists

investigate how the planets and

the Sun were formed

OSIRIS-REx made Bennu the

smallest object ever to be

orbited by a spacecraft and

set the record for the closest

orbit of a planetary body

by a spacecraft.

Bennu may have been a part of

a larger carbon-rich asteroid that

was broken off 700 million to

2 billion years ago.

Observations revealed Bennu

absorbs the Sun’s radiation

and then re-radiates it to

give it a push, known as the

Yarkovsk y ef fec t.

700 million

to 2 billion

Bennu