Seven years after it left for the near-Earth asteroid Bennu, NASA’s OSIRIS-REx spacecraft is returning with a celestial memento. On the morning of Sunday, September 24, because it passes by Earth the probe will launch a canister holding about 9 ounces of house rock. The container will plummet via the ambiance, its parachute will unfurl, and it’ll contact down within the Utah desert at about 8:55 am Mountain time.

Assuming its contents survive the journey unscathed, the return will mark a tantalizing step ahead for planetary science. Researchers have lengthy salivated over the prospect of analyzing pristine asteroid fragments. While meteorites—which are sometimes damaged chunks of asteroids—fall from the sky on a regular basis, they’re instantly contaminated by the bottom they smash into. This shall be a uncommon have a look at an untainted rock from house, and it’ll assist scientists perceive what Bennu is fabricated from and the place it got here from. If the mission is profitable, it will likely be solely the third asteroid pattern return in historical past—following Japanese space agency missions to Ryugu and Itokawa.

To planetary scientist Dante Lauretta, the mission’s principal investigator, it’s additionally “a little bittersweet,” as a result of this system is now coming to an finish. Still, he says, “I’m excited to get it into the laboratory, so we can do all this amazing science.” His University of Arizona workforce will examine the composition of the mud and rock fragments within the container and hint any natural molecules they might harbor. The scientists will even have the ability to examine samples of Bennu to Ryugu.

But first, the capsule, which is round and concerning the dimension of an ice chest, has to make it safely all the way down to Earth. That will imply slowing from 28,000 miles per hour to only 11. Lockheed Martin constructed the spacecraft for NASA and is accountable for the capsule restoration. “We have done sample returns before, so we have that experience,” says Sandra Freund, a techniques engineer at Lockheed and the OSIRIS-REx program supervisor, referring to earlier NASA missions that collected supplies from a comet and the photo voltaic wind. “We know we can do this, but there’s always a risk when you’re bringing something back to Earth. You’ve got atmospheric reentry, which is a very fiery experience. You’ve got parachutes that need to deploy. So there are a number of things that need to go just right.”

The capsule’s built-in warmth defend is designed to put it aside from burning up at 5,000 levels Fahrenheit, as a meteor or unprotected satellite tv for pc that dimension hurtling via the ambiance would. “Any time you want to bring a payload through the atmosphere, you need protection for it. It can be pretty gnarly,” says Todd White, a scientist at NASA Ames Research Center in Mountain View, California, who labored on the spacecraft’s thermal safety system. The warmth defend is fabricated from a light-weight chopped carbon fiber infused with resin, and it’s ablative, that means that it slowly burns off. “It looks nice and brown on the back and white on the front—but when it lands it’ll look charred and crispy,” White says.

First, the capsule will deploy a small drogue chute to maintain itself steady. Then seven minutes into its descent, it can open its most important parachute and drift to the bottom for six extra minutes. Recovery helicopters will get the primary view of its fast descent. Relatively comfortable soil ought to cushion the affect when it lands inside the Department of Defense’s distant Utah Test and Training Range and Dugway Proving Grounds. It’s an energetic vary, although, so earlier than NASA personnel make their method to retrieve the container, a navy consultant will verify the realm to verify there’s no unexploded ordnance.