NASA’s OSIRIS-REx mission team found thermal cracks on Asteroid Bennu due to the Sun. This is what it suggests.
NASA’s OSIRIS-REx mission again came up with interesting information about the age of the asteroids. A recent report revealed that scientists learned that surface regeneration of some asteroids happens a lot quicker than on Earth. The results emerged by analyzing rock fractures on the famous asteroid Bennu taken by the OSIRIS-REx spacecraft. The scientists found that heat from the Sun fractured rocks on asteroid Bennu in just 10,000 to 100,000 years. NASA’s scientists used a computer model and fracture measurements to calculate this timeframe for thermal fractures.
This huge timeframe might sound slow, but senior scientist Marco Delbo has to say, “We were surprised to learn that the aging and weathering process on asteroids happens so quickly, geologically speaking.” The rapid temperature changes on asteroid Bennu built up the internal stress which resulted in fractures and breaking down rocks. NASA compared it to how a cold glass breaks under hot water. You would be surprised to know that the Sun rises every 4.3 hours on Bennu, and even at the equator, during the daytime, the highest temperature can reach almost 260 Fahrenheit. During the night-time, the lowest temperature can go down to around minus 10 Fahrenheit.
Asteroid Bennu surface revealed a secret
The team of scientists from the OSIRIS-REx mission found cracks in the rocks from the first surveys of the asteroid. These fractures follow the same path, and predominantly align in the northwest-southeast direction. According to Delbo, “a distinct signature that temperature shocks between the day and the night could be the cause.” The same pattern indicates that they were caused by the Sun.
These thermal fractures on Bennu caused by the Sun are quite similar to what we find on Earth or even Mars, a scientist Christophe Matonti suggested. “It is fascinating to see that they can exist and are similar in very ‘exotic’ physical conditions [low gravity, no atmosphere], even compared to Mars.”
NASA says that this information about the asteroid thermal cracks will help scientists to estimate how long it takes boulders on asteroids like Bennu to break down into smaller particles and whether they eject into space or stay on the asteroid’s surface.