Last updated August 15, 2018 at 3:21 pm
Hayabusa2 snapped this close-up of asteroid Ryugu less than 6km from the surface.
Asteroid Ryugu from an altitude of 6km. Image was captured with the Optical Navigation Camera – Telescopic (ONC-T) on July 20, 2018 at around 16:00 JST. Credit : JAXA, University of Tokyo, Kochi University, Rikkyo University, Nagoya University, Chiba Institute of Technology, Meiji University, University of Aizu, AIST.
Hayabusa2, JAXA’s asteroid chasing spacecraft, snapped this close-up image of its target, Ryugu, on July 20.
Taken from an altitude of just 6km, the resolution is about 3.4 times higher than previous images. 1 pixel in the image corresponds to about 60cm.
The largest crater on the surface of Ryugu is near the centre of the image showing its “mortar” shape. The photo also reveals that the surface of Ryugu is covered with a large number of boulders.
Hayabusa2 arrived at Ryugu in June this year, and originally held at a position 20km above the surface. During July the craft gradually moved closer to the asteroid until it reached a minimum altitude of 6km, when this photo was taken. It stayed at the low altitude for around a day before moving back to its 20km “Home” position.
Images like this are vitally important to the mission. Later this year Hayabusa2 will begin its mission to sample the asteroid directly, including landing rovers on the surface of the asteroid itself. The images being captured now will assist the selection of the landing site.
In addition to the rovers, Hayabusa2 will also descend close to the surface of Ryugu where it will take a sample of the rock. Those samples will be brought back to Earth for study, landing at Woomera in 2020.
The rock sampling part of the mission will be similar to Hayabusa2’s earlier counterpart, Hayabusa. An impactor – essentially a bullet made out of the exotic tantalum – will be shot out of the sampling mechanism. The impact between bullet and asteroid surface will spray debris out and up, where it will be captured by the spacecraft.
A second sampling mission will be far more spectacular. To investigate the subsurface structure of the asteroid, which has not been subjected to weathering, a 2.5kg copper rod will be dropped from Hayabusa2, along with 4.5kg of plastic explosive. Leaving behind a camera to watch the explosion, Hayabusa2 will maneouvre to the opposite side of the asteroid to avoid debris, while the explosive and rod drift towards the surface.
When in place, the explosive will detonate, driving the copper rod into Ryugu and breaking through the surface. About 2 weeks later, once the debris has cleared, Hayabusa2 will return to the impact site and take samples from inside the resulting crater.
Related
Space pic of the week: the story of a gigantic Aussie crater
To the stars and beyond – reasons to look up in 2018
Space pic of the week: Hubble snaps Mars and Saturn’s portraits
Education Resource:
Ryugu is ready for its close up
