NASA is preparing to collect asteroid samples returned from space for the first time by the United States. NASA's OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Rock Explorer) mission has been flying in space for many years, and soon, samples collected by the mission from the asteroid Bennu will land on Earth. This sample was earlier released from the OSIRIS spacecraft, and after being renamed OSIRIS-APEX, the probe is now en route to another asteroid.
A capsule carrying samples of asteroid Bennu will land at the U.S. Air Force's Utah Test and Training Range later today.
The asteroid returned by today's sampling mission is no ordinary asteroid. In fact, researchers have determined that Bennu is likely to hit the Earth more than a thousand years from now, and the asteroid is currently traveling at 63,000 kilometers per hour. According to orbital parameters, its closest distance to the Earth is 430,000 kilometers. It is estimated that Bennu may impact the Earth in 2135. Such a collision would be more destructive than a random asteroid strike.
Earlier today, the landed sample was ejected from the OSIRIS spacecraft with permission from ground controllers. If ground controllers do not approve this return mission, the spacecraft will miss Earth and the next opportunity to return samples will be in 2025. Earlier this month, the spacecraft activated its thrusters, placing it in Earth's orbit, allowing it to adjust its speed relative to Earth and avoid a flyby. OSIRIS-REx released the sample capsule at 6:42 a.m. ET while it was 63,000 miles above the Earth's surface.
NASA's map of the sample's return to Earth. Image NASA
The capsule's return to Earth will be one of the most dangerous parts of its journey, as it must withstand the extreme forces in the atmosphere. The return capsule is scheduled to return at an altitude of 433,000 feet, while the sampling capsule is traveling at 27,000 miles per hour. The remainder of the reentry capsule's entry into the atmosphere will be typical of what has been observed with other spacecraft, such as those returning from the International Space Station and the Moon. First, the capsule's parachutes will deploy to slow it down, and then the main parachute will deploy about five minutes before the capsule lands in the desert.
The capsule itself is much smaller compared to other spacecraft. It weighs 46 kilograms, has a diameter of 81 centimeters and a height of 50 centimeters. It is expected to take only 13 minutes from re-entry to landing. Because the asteroid is large and difficult to track, the team will also fly in a helicopter and use the capsule's heat signature to provide tracking data to optical instruments, which will then map the return trajectory.
The asteroid rocks and materials in the capsule will be made available to researchers around the world. After ejecting the capsule, the OSIRIS spacecraft (now called OSIRIS-APEX) will travel to the asteroid Apophis. It is scheduled to reach the asteroid in six years, after which it will orbit the asteroid for a year and a half.