Nasa’s first asteroid-sampling mission is set to begin in just three weeks.
But scientists will have to wait until 2023 to study the sample, which it’s hoped will shed light on how planets formed and how life began, as well as improving our understanding of asteroids that could hit Earth.
OSIRIS-REx, which stands for The Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer is scheduled to launch at from Cape Canaveral Air Force Station at 7.05PM EDT in Florida on September 8 (00:05BST September 9).
“This mission exemplifies our nation’s quest to boldly go and study our solar system and beyond to better understand the universe and our place in it,” said Geoff Yoder, acting associate administrator for the agency’s Science Mission Directorate in Washington.
“Nasa science is the greatest engine of scientific discovery on the planet and OSIRIS-REx embodies our directorate’s goal to innovate, explore, discover, and inspire.”
The 4,650 pound fully-fuelled spacecraft will blast off atop an Atlas V 411 rocket during a 34-day launch period and will reach the 1,600 foot asteroid target in August 2018, if the first phase of the $800 million mission goes to plan.
The craft will orbit the asteroid for around two years in order to map it and locate the most promising sample sites before moving to the asteroid’s surface in around June 2020.
"We don't technically land on Bennu, but we make contact with it for about five seconds," Jeff Grossman, OSIRIS-REx program scientist explained at a press conference.
During the five seconds, the probe will blast a small patch of the asteroid’s surface with gas, so it can and collect the material that's blown out, Space.com reported. OSIRIS-REx will collect between 60 grams and two kilos of surface material with its robotic arm.
It will return the sample to Earth via a detachable capsule in 2023, destined to land gently with the aid of parachutes in the Utah desert, while the craft is ‘parked’ orbiting the sun.
"The launch of OSIRIS-REx is the beginning a seven-year journey to return pristine samples from asteroid Bennu," said OSIRIS-REx Principal Investigator Dante Lauretta of the University of Arizona, Tucson.
"The team has built an amazing spacecraft, and we are well-equipped to investigate Bennu and return with our scientific treasure."
The precious sample could contain the earliest materials found in the solar system, at around 4.5 billion years old and could reveal secrets about how life began on Earth. The team will hunt for organic molecules – the building blocks of life – in the sample.
The spacecraft has two systems that will enable it to collect the rock and return it to Earth.
The first is called the Touch-And-Go Sample Acquisition Mechanism (TAGSAM). It comprises an articulated robotic arm with a sampler head provided by Lockheed Martin Space Systems in Denver, to collect a sample of Bennu's surface.
And the second, OSIRIS-REx Sample Return Capsule (SRC) is a capsule with a heat shield and parachutes in which the spacecraft will return the asteroid sample to Earth.
The craft also has five instruments on-board with which to explore Bennu, with the dual aim of detecting conditions necessary for life, and valuable resources.
They include a camera system called OCAMS, which consists of three cameras to image Bennu and record the ‘sampling event’ when the rock is collected.
LIDAR will be used to measure the distance between the spacecraft and Bennu's surface, and will map the shape of the asteroid.
OSIRIS-REx's Thermal Emission Spectrometer (OTES) will provide scientists with temperature information, while its Visible and Infrared Spectrometer (OVIRS) will measure visible and infrared light from Bennu to identify mineral and organic material.
Lastly, a device on-board called Regolith X-ray Imaging Spectrometer (REXIS) will observe the X-ray spectrum to identify chemical elements on Bennu’s surface and their abundances. This may be of interest to scientists who dream of mining asteroids for rich natural resources.
The data may also be useful in potentially mitigating a disastrous event for mankind. This is because there’s a slim chance Bennu could collide with Earth in 170 years time, with the greatest risk – one in 1,000 – occurring in 2182.
While OSIRIS-REx may be Nasa’s first asteroid-sampling mission, it is not the first one ever. Japan has embarked on two such missions, with the first, called Hayabusa, sending pieces of asteroid Itokawa back to Earth in 2010.