At a NASA press conference, some of the samples are leaking into space, according to Dante Lauretta, senior researcher at OSIRIS-REx at the University of Arizona in Tucson.
“The big concern now is that the particles are escaping because we are almost the victims of our success,” he said. “Large particles have their flaps open. Particles are spreading into space. They don’t move fast, but they are nonetheless valuable scientific data.”
The mission team analyzed images of the spacecraft collector heads that showed that significant samples were collected on Thursday, but there was too much material on the head to clog the flaps designed to hold the samples inside.
This allows the particles to escape into space. The mission team is changing the course of the event planned for the spaceship this weekend, and plans to store samples as soon as possible with little material loss. Researchers have estimated that 5 to 10 grams of the substance is constantly being lost. This flaky material floats in a shape similar to a cloud of particles around the head.
However, because the team is not constant, we are not sure of the exact loss rate.
This mission required collecting at least 2 ounces (60 grams) of asteroid surface material. Based on the images they analyzed, the researchers are convinced that the collector head at the end of the spacecraft’s robotic arm actually captured 400 grams of material. And it’s only visible to them through the camera’s point of view.
However, the particles are escaping through small gaps with mylar flaps (lids) open at least 1 cm by large rocks. And the activity planned on the spacecraft this weekend could cause more sample loss due to motion.
Previously, OSIRIS-Rex was expected to conduct braking combustion on Friday and to measure the mass of the sample on Saturday. This means that the actual mass of the sample will not be known until the team returns to Earth in 2023, but the mission team is confident there will be enough samples.
“We are trying to keep up with our own success here, and my mission is to safely return as many Bennu samples as possible,” Lauretta said. “I am concerned about mass loss, so I strongly recommend that the team store this valuable sample as soon as possible.”
The team will go through another evaluation process this weekend to keep the sample heads in sample return capsules by Tuesday to protect loose material and secure valuable cargo so you can return to Earth.
The sample head is too full due to the way the Tuesday collection event proceeded unexpectedly.
Collectors were in direct contact during the event on Tuesday and some did. When the head touched down, it sank 5 centimeters to the surface of the asteroid for 6 seconds. When a bottle of pressurized nitrogen gas designed to lift material from the surface was fired, the head sank an additional 24 to 48 cm to the surface material.
There’s no way to close the flap, Lauretta said. The team isn’t sure of the power of the rock that keeps it open, he said, but it should be strong against the size limits it can pass to the collection head.
This wasn’t what the team met in a test campaign before embarking on a mission involving sample collection heads buried in large rocks and asteroid’s surface material. However, the researchers didn’t test the sample head at a depth they suspected had actually reached an asteroid.
“Bennu continues to surprise us with great science and threw a few curveballs,” said Thomas Zurbuchen, deputy manager of NASA’s Director of Science Missions at the institutional headquarters in Washington.
“You may have to move faster to keep the samples, but it’s not bad to have a problem. We’re excited to see what appears to be a rich sample that will inspire science for decades after this historic moment.”
Regardless of when the sample is stored next week, the spacecraft will not return to Earth until March 2021, when an asteroid currently 200 million miles from Earth is aligned with Earth to return to a more efficient home. .
According to the team, the spacecraft “stays in good shape” to return to Earth.