Keegan Barber/NASA
This was the second Dante Lauretta had waited for almost 20 years to see. A small robotic capsule was on the way in which again to Earth with rocks scooped from an asteroid, and Lauretta was desperate to get his fingers on the samples.
Led by Lauretta, scientists rigorously designed the billion-dollar mission to convey residence items of a carbon-rich asteroid thought to include natural molecules, the constructing blocks essential for all times to take maintain. This NASA mission, identified by the acronym OSIRIS-REx, launched from Earth in 2016, collected samples from a roughly 1,600-foot-wide (500-meter) asteroid named Bennu in 2020, then set a course for return to Earth.
On September 24, the OSIRIS-REx spacecraft launched the canister containing the asteroid samples to plunge into the Earth’s ambiance, whereas the mothership steered onto a course to take it safely again into deep area for a follow-up mission to discover a special asteroid on the finish of the 2020s.
Lauretta, OSIRIS-REx’s principal investigator from the College of Arizona, was a passenger in a US army helicopter circling the capsule’s touchdown zone within the Utah desert. A warmth protect protected the capsule from temperatures that constructed as much as greater than 5,000° Fahrenheit throughout reentry.
Then, a small drogue parachute was presupposed to open to stabilize the 32-inch-wide (81-centimeter) pattern return craft. About 5 minutes later, a bigger primary chute would open to gradual the capsule for a mild touchdown whereas defending the dear asteroid materials sealed inside.
At the very least, that was the plan. Whereas OSIRIS-REx safely returned its asteroid pattern to Earth, there have been moments of excessive drama.
Out of order
For these watching NASA’s reside video protection of the OSIRIS-REx mission’s return to Earth, there have been hints that one thing was amiss. Video imagery from a NASA monitoring airplane confirmed the capsule tumbling towards the bottom at excessive pace, effectively after the purpose when the drogue parachute ought to have been seen.
Inside a close-by helicopter, Lauretta was ready for verbal updates on the standing of the capsule.
“I heard the 100,000-foot crossing, and no drogue, and the drogue chute is meant to return out at 100,000 toes,” he recalled throughout a presentation final month to the Nationwide Academies’ Area Research Board. “Sixty-thousand toes, no drogue. I’m like, ‘Ugh, this isn’t good.'”
The final time NASA tried to convey extraterrestrial samples again to Earth, the parachute by no means opened. The robotic Genesis mission ended with an uncontrolled affect in Utah, rupturing the capsule bringing again microscopic particles collected from the photo voltaic wind. Scientists had been in a position to salvage a number of the specimens, however it wasn’t straightforward.
Lauretta referred to as a crash just like the one skilled by NASA’s Genesis mission because the “worst-case state of affairs” for OSIRIS-REx. In that occasion, scientists would want to scramble to assemble as a lot of the asteroid pattern as doable from the Utah desert. Something salvaged would must be rigorously checked for contamination from Earth’s soils and life-forms.
You may watch a replay of OSIRIS-REx’s touchdown under.
“We’re tumbling. We’re in a subsonic regime, and we’re not stabilized,” Lauretta stated. “There’s no drogue chute deployed right here. Downside! So I used to be like attempting to mentally put together myself, as a result of we’re on reside TV, to get off this helicopter and cope with a crashed capsule within the desert.”
Then, Lauretta heard affirmation from the Air Pressure that the OSIRIS-REx return capsule had unfurled its primary parachute.
“I used to be like, ‘What? How is that doable?'” he stated. “So the primary chute deployed. The drogue chute, as we’ve been in a position to reconstruct, went one second earlier than the primary. So it got here out. It needed to come out. It was in entrance of the primary parachute within the canister, and it appears to be like like there was a circuit difficulty.”
NASA offered a extra detailed description Tuesday of the issue that prevented the on-time deployment of the drogue chute.
The capsule was presupposed to ship an automatic sign to deploy the drogue chute at 100,000 toes, starting a roughly five-minute timer earlier than a second sign would minimize a retention wire for the drogue, permitting the bigger parachute to unfurl and full the touchdown sequence. As a substitute, at 100,000 toes, the sign triggered the system to chop the drogue free whereas it was nonetheless packed contained in the capsule, in response to NASA.
At 9,000 toes, the opposite sign despatched the command to truly launch the drogue chute. However with its retention wire already minimize, the drogue instantly launched from the capsule, and the primary parachute opened as anticipated.
“The primary sign was supposed to fireplace the mortar and launch the drogue,” Lauretta stated. “The second sign was supposed to chop the cable to launch the primary … It appears to be like like the primary sign minimize the (cable), after which the second sign fired the mortar, so it went backwards. But it surely labored. We had numerous margin on that primary chute. It landed safely—a gorgeous pinpoint touchdown within the Utah desert.”
An investigation by engineers from NASA and Lockheed Martin, which constructed the OSIRIS-REx spacecraft and pattern return car, discovered that construct plans for the mission weren’t particular sufficient in instructing technicians who assembled the return capsule.
“Within the design plans for the system, the phrase ‘primary’ was used inconsistently between the system that sends the electrical indicators, and the system that receives the indicators,” NASA stated in a written assertion. “On the sign facet, ‘primary’ meant the primary parachute. In distinction, on the receiver facet ‘primary’ was used as a reference to a pyrotechnic that fires to launch the parachute canister cowl and deploy the drogue.
“Engineers related the 2 mains, inflicting the parachute deployment actions to happen out of order,” NASA stated.
Lauretta stated scientists proceed analyzing the asteroid supplies delivered by OSIRIS-REx.
In a preliminary evaluation of a number of the mud, scientists discovered almost 5 % carbon by mass, and the fabric has considerable water within the type of hydrated clay minerals. It’s extremely believable that asteroids like Bennu delivered the overwhelming majority of the water now present in Earth’s oceans, lakes, and rivers billions of years in the past.
The group tasked with retrieving the samples from the capsule at NASA’s Johnson Area Middle in Houston has encountered bother opening a number of the fasteners sealing the asteroid materials in the primary assortment chamber. Whereas the group labored on a brand new plan to assemble all of the asteroid specimens held inside, it used tweezers to tug out a number of the largest items, together with a roughly 1.2-inch (3-centimeter) fragment straight from Bennu.
“The natural chemistry appears to be like improbable,” Lauretta stated.