On Sunday (24 September), US space agency NASA’s OSIRIS REx spacecraft released the capsule that contains a piece of near-Earth asteroid named Bennu. As per official information, the capsule descended through space for four hours and then entered the atmosphere over California, subsequently landing about 13 minutes later in Utah.
The #OSIRISREx spacecraft has released the capsule containing a piece of asteroid Bennu. The capsule will plummet through space for four hours, enter the atmosphere over California and land about 13 minutes later in Utah. https://t.co/lK5QmILjtj pic.twitter.com/gECoNC1sHU
— NASA Solar System (@NASASolarSystem) September 24, 2023
The sample capsule contains an estimated 8.8 ounces (250 grams) of asteroid rocks and soil from asteroid Bennu and it landed near Salt Lake City at 10:55 AM ET today (8:25 PM IST). A recovery mission has been launched to locate and retrieve the capsule.
Earlier in the day, the Osiris-Rex spacecraft reached within 63,000 miles of Earth’s surface which is about one-third the distance from Earth to the moon. From there, the spacecraft released the sample capsule at around 6:42 AM ET.
The capsule then travelled for four hours at 27,650 miles per hour and entered Earth’s atmosphere at around 10:42 AM ET (8:12 PM IST) off the northern California coast at an altitude of about 83 miles above the surface. 13 minutes later, the capsule finally landed at an area on the defence department’s Utah Test and Training Range near Salt Lake City. Parachutes were deployed to slow the capsule to a gentle touchdown at 11 miles per hour (17.7 kilometres per hour).
Notably, NASA’s OSIRIS-REx spacecraft stands for Origins, Spectral Interpretation, Resource Identification, Security and Regolith Explorer. This seven-year mission planned to study what scientists have described as the most dangerous rock in the Solar System began in 2016 when it lifted off with an aim to collect samples from the Bennu asteroid. It then began orbiting Bennu in 2018 and the spacecraft later collected the sample in 2020 using a long sting vacuum and subsequently set off on its lengthy return trip to Earth in May 2021.
Now, the Osiris-Rex spacecraft has brought back the pristine sample collected from the near-Earth asteroid Bennu. It’s NASA’s first time returning an asteroid sample from space. Earlier, Japan had collected around a teaspoonful of samples in two asteroid missions.
The capsule has no GPS tracker onboard so it was spotted using long-range telescopes and infrared cameras, BBC reported. Recovery and research teams are reaching the landing site in 4 helicopters, and they will take lots of precautions before retrieving the capsule. First, they will conduct an aerial study to confirm that it is not damaged. After that, they will wait for the capsule to cool down so that it is safe to handle. The capsule reached temperatures up to 2,760° Celsius while descending through the atmosphere. The teams have been training for it for months and conducted several simulations of the capsule recovery.
A clean room has also been set up by NASA at the location to handle the capsule.
As per official information, Bennu is a carbonaceous asteroid which means that it has a lot of carbon in it, perhaps 5-10% by mass. It is expected that Scientists could see a mix of rocky fragments in a range of sizes – from a few millimetres across down to dust-sized. The material will appear very dark, almost black, and very crumbly.
The asteroid Bennu was discovered in 1999. It is a ‘rubble-pile asteroid’ meaning that it is a large jumble of space rocks compressed together by gravity. It is believed that these rocks got broken off from a larger body, and are about 4.6 bn years old which means it is approximately the same time as the solar system, the Guardian reported.
The asteroid is orbiting the sun 81 million kilometres from Earth, and its surface is so loose that Osiris-Rex’s vacuum arm sank a foot or two into the asteroid. As a result, it sucked up much more sample than anticipated, and the lid of the container was jammed.
Regarding the sample, NASA said, “Pieces of 4.6bn-year-old space rock ‘act as a time capsule from the earliest days of our solar system.” The samples will be flown to a new lab at NASA’s Johnson Space Center in Houston, where the container will be opened.
Strikingly, the asteroid is known to be rich in carbon-based substances and water-containing clay minerals. This suggests that liquid water was once present on the larger body from which Bennu formed.
Researchers believe the samples collected could help scientists understand the ingredients that went into making planets including our own. It could also help them understand how those materials came together to create environments suitable for life.
It is believed that Bennu will likely also have a lot of water bound up in its minerals, perhaps as much as 10% by mass. Similarly, akin to carbon chemistry, the delivery of water through asteroid impacts might offer an explanation for the abundant presence of H2O on our planet.
After the release of the capsule, OSIRIS-REx resumed its tour of the solar system and is now headed towards a different asteroid named Apophis for a detailed study.
