[imagesource: NASA/Goddard/University of Arizona]

NASA has been making waves this year with so many discoveries, launches, and advancements in science that it’s hard to keep up.

At one point I was binge-watching NASA TV with the same enthusiasm that I usually reserve for Netflix.

The latest addition to the watch list will be live-streamed tonight.

For close to two years, a small spacecraft called Osiris-Rex has been orbiting a large asteroid more than 100 million miles away from Earth.

Tonight, in a first for NASA, Osiris-Rex will briefly touch down on a large asteroid and grab some rocks and dust from its surface to be returned to Earth for study, in what they’re calling a “high five manoeuvre”.

This marks a major boon for science, space exploration, and our understanding of the solar system.

Before we go into more detail about the little probe that could, you need to get to grips with the size of the asteroid, Bennu.

BBC says that Bennu is roughly the size of the Empire State Building, and looks a little like a spinning top.

The primary site which will be ‘high fived’, dubbed Nightingale, is eight metres wide, or the length of a few parking spaces.

“For some perspective: the next time you park your car in front of your house or in front of a coffee shop, and walk inside – think about the challenge of navigating Osiris Rex-into one of these spots from 200 million miles away,” remarked Mike Moreau, Nasa’s deputy project manager on the mission.

Over to WIRED for how Osiris-Rex will make contact.

Shortly before 11PM tonight, Osiris-Rex will fire its thrusters, beginning a slow descent from its orbit above Bennu.

It’s going to take roughly four and a half hours to travel just a kilometre to the surface.

“Everything around this asteroid happens slowly,” says Richard Burns, the Osiris-Rex project manager at NASA’s Goddard Flight Center.

“This is the one thing we haven’t done, so we don’t know what’s going to happen,” says Burns. “We’re cautiously optimistic that this will be the only time we touch the surface.”

The spot chosen for Osiris-Rex to tap down, before using a reverse vacuum-cleaner type device to scoop up a sample, is relatively young, which means that the rock is likely to consist of pristine remnants from when the asteroid was formed billions of years ago.

The probe will lower an arm, sporting the vacuum, which will blow a small burst of nitrogen gas onto it to stir up some dust and rocks. These will then be collected on a ring around it designed to attract rocks and dust.

“We weren’t certain what the surface was going to look like,” says Mark Fisher, a space engineer at Lockheed Martin who worked on building the sample collection arm. “We thought it was going to have a lot more fine-grain material, but there’s lots of big rocks on the surface. And that makes it hard to get some smaller rocks into the sampler.”

Dante Lauretta, a planetary scientist at the University of Arizona, says that the material collected from Bennu will help scientists to assess the “likelihood of the origin of life occurring throughout the galaxy and, ultimately, throughout the universe”.

So it’s a big deal.

Once the material has been collected, phase two is a little tougher.

“Getting back into orbit is a tricky business, and it’s time consuming to plan the observations necessary to get our bearings again,” says Burns. “The spacecraft is taking images and matching them with known surface features to update the orbit.”

If the probe fails, it will have one more attempt to get it right. If that doesn’t work, it will try again in December.

Gripping stuff.

You can watch the most epic high five in history live tonight, starting from 11PM:

[source:wired&bbc]