When NASA’s OSIRIS-REX spacecraft touched the surface of an asteroid on Tuesday to collect a sample of rocks and dirt, the process continued smoothly, much to the delight of the mission operators.
“Transcendent,” said Dante Loretta, the mission’s principal investigator, moments later. “I mean, I can’t believe we’ve actually done that.”
But the bigger question remained unanswered: How much of the asteroid Osiris Rex captured? Were you able to collect any samples at all?
With an asteroid – a rock called Benno roughly as wide as the Empire State Building – only exerting a tuft of gravitational pull, it simply wasn’t possible to place the sampling container on a scale and weigh it.
Additionally, the spacecraft was unable to transmit much data as it swooped in to try to collect it. It was on the other side of the solar system, more than 200 million miles from Earth, and when it descended towards the asteroid, its main antenna was not pointed at our planet. This means that Osiris Rex can only provide primitive “breadcrumbs” that inform mission controllers of its position, velocity, and state, but not images of the asteroid that reveal the spot that touched the spacecraft.
Scientists have chosen a target they call Nightingale, located inside a volcano near the north pole of Beno.
After collecting the sample, the spacecraft retreated from the asteroid and returned to a higher orbit. From there, it can start sending the data packets you have collected back to Earth.
NASA is scheduled to post some pictures at a Wednesday 5 p.m. press conference, and the press conference will be broadcast on NASA TV.
These photos should provide more clues, but scientists still won’t determine the amount of material trapped inside the sample complex, which resembles a car air filter, until Saturday.
“There is an incredibly clever physics experiment designed by the team here called mass sampling,” said Dr. Loretta during a NASA TV broadcast on Tuesday.
The robotic arm will be extended with the sample collector at the end, and then the spacecraft will be propelled into orbit on Saturday. “We are measuring a property called moment of inertia,” said Dr. Loretta.
Scientists will compare the rotation rate to what they measured before collecting the sample. Just as a skater with outstretched arms rotates and grasps a rod slower than a skater holding nothing, the Osiris Rex will spin slower depending on the amount of material captured.
Scientists hope she will gain at least an ounce, but it can weigh more than four pounds.
“The accuracy, just like everything in this program, is enormous,” said Dr. Loretta. “We are talking about tens of grams of accuracy about a measurement on a spacecraft hundreds of millions of miles away.”
If Osiris Rex appears blank on Tuesday by accident, he can try two more times
The asteroid sample collection marks the culmination of the $ 800 million mission, which launched four years ago. The spacecraft made detailed observations of Benno for two years, and mapped its tiny surface just a few inches wide. It even discovered that Benno was spewing debris from its surface into space.
Asteroids, which often lie in orbits between Mars and Jupiter, are parts that never coalesced to form a planet, and planetary scientists hope that samples from Bennu will shed light on the shape of the young solar system when it formed 4.5 billion years ago. Asteroids like Bennu, which have minerals rich in carbon, may have provided the building blocks for life on Earth.
The asteroid is also being studied because its orbit could cause it to collide with Earth in the late 22nd century. The likelihood of such a occurrence is low, and an asteroid is not large enough to end human civilization should it occur.
OSIRIS-REX – the name is an acronym for Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer – is an asteroid departure next year and a sample drop, which will parachute to landing in Utah on September 24, 2023.