The asteroid Bennu – the goal of the NASA mission return mission – spins over time, an observation that can help understand the evolution of asteroids and their potential threat to the Earth, scientists say.
Bennu is located 110 million kilometers from Earth. As it travels through the universe with about 101,000 kilometers per hour, it also revolves, ending the full rotation every 4.3 hours.
Last year, he arrived at Bennu, an asteroid to study and sample in the next few years.
The research, published in the Geophysical Research Letters, showed that the asteroid rotation accelerated for about a second in a century.
In other words, the Bennu rotation period is reduced by about one second every 100 years.
While the increase in rotation may not seem like much, over a longer period of time it could turn into dramatic changes in the space rock, scientists say.
As the asteroid spins faster and faster over millions of years, it can lose pieces of itself or blow it up alone, they say.
Revealing the increase in rotation helps scientists understand the kinds of changes that might occur on Bennu, such as landslides or other long-term changes that the OSIRIS-REx mission will require.
"As it accelerates, things need to change, and so we will look for those things, and the discovery of this acceleration gives us some clues about the kinds of things we need to look for," says Mike Nolan, a senior research scientist on the Moon, and planetary laboratory at the University of Arizona in the United States.
"We need to look for evidence that something is different in a fairly recent past and it is possible to change things as we go," said Nolan, who is the head of the OSIRIS-REx mission team.
The OSRIS-REx mission is to bring a sample of Bennu on Earth in 2023.
Understanding the rotational changes of Bennu can help scientists find out what asteroids can tell us about the origin of the solar system, how likely it is that asteroids are a threat to humans and whether they can be mined for resources.
To understand Bennu's rotation, scientists studied data on the asteroid taken from Earth in 1999 and 2005, along with data from the Hubble Space Telescope in 2012.
It was when they looked at Hubble data that they noticed that the asteroid's rotational speed in 2012 did not match their predictions based on previous data.
The idea that the asteroid rotation could accelerate over time was first predicted around 2000 and first discovered in 2007. To date, this acceleration has been discovered only in a few asteroids, Nolan said.
(This story has not been changed by Business Standard staff and is automatically generated from a syndicated source.)