How Australia will help NASA space mission
Hurtling at 101,000km/h, the OSIRIS-REx spacecraft will on Wednesday morning attempt to land on asteroid Bennu as Australia's deep space radar network provides NASA with vital tracking and communications.
The ambitious mission to collect samples from Bennu, 332 million kilometres away, and return them to Earth will give scientists a rare window into the history of the universe but also into the make-up of the 500m-wide asteroid which has a small but 1-in-2700 chance of colliding with our planet between 2175 and 2199.
"Between 9:10 and 9:30am on Wednesday morning, the giant antennas of NASA's Deep Space Network tracking station in Canberra will be monitoring the so-called "Touch and Go" (TAG) sequence as the spacecraft eases down between some building-sized boulders to briefly set-down in a small crater on Bennu called Nightingale," CSIRO spokesman Glen Nagle said.
A number of Australian scientists are part of the OSIRIS-REx program, helping design mission requirements, interpreting instrument data and mapping the 4.5 billion-year-old asteroid.
OSIRIS-REx launched from Cape Canaveral in 2016, arrived at Bennu in December 2018 and spent almost two studying and identifying landing sites before it will today perform the TAG manoeuvre to vacuum 56 grams of regolith dust and rock from the asteroid surface, with a 2kg sample possible.
If all goes to plan, the robotic craft will return to Earth and jettison its sample capsule above the Utah desert in September 2023.
At the Canberra Deep Space Communications Complex, two 34m antennas have been helping track and communicate with OSIRIS-REx since lift-off and will be integral to today's landing.
"During the nearly six-hour descent sequence, NASA expects that the signal coming from OSIRIS-REx could drop out several times, requiring the operators in our control centre to try and quickly reacquire a very tiny signal that could be fluctuating in and out of lock." Mr Nagle said.
"It's something that our experienced operators have trained for and are confident of success. When it comes to critical events like these you want to ensure that the spacecraft's scientists have all the information they can get. We're ready to deliver for them."
DSN Canberra is one of three communications lifelines with the mission.
NASA has rated Bennu as "one of the most potentially hazardous asteroids (with) a relatively high probability" of Earth impact if it hits an orbit-altering "keyhole".
While not an existential threat, gaining precise position data will enable scientists to track its pass between us and the moon in 155 years - still 299,000km away - and launch a mitigation mission to knock it from course if necessary.
Originally published as How Australia will help NASA space mission