The saying ‘what you don’t know can’t hurt you’ might apply in some situations, but not when discussing asteroids on a collision course with Earth.
A scientist has highlighted the fact that NASA is unaware of the locations of certain potentially catastrophic asteroids, which causes her significant concern.
Kelly Fast leads the planetary defense initiatives at the US agency responsible for monitoring near-Earth objects and devising strategies to avert potential planetary destruction.
In her words, her job is to locate asteroids ‘before they find us’ and to create methods of ‘getting asteroids before they get us.’
In a presentation to the American Association for the Advancement of Science, she explained, as reported by the Sun: “What keeps me up at night is the asteroids we don’t know about.
“Small stuff is hitting us all the time so we’re not so much worried about that.
“And we’re not so worried about the large ones from the movies because we know where they are.
“It’s the ones in between, about 140 metres and larger, that could really do regional rather than global damage and we don’t know where they are.”
She further mentioned that there are approximately 25,000 of these asteroids and ‘we’re only about 40 percent of the way through.’
“It takes time to find them, even with the best telescopes,” she remarked.
Previous research has indicated the threat of multiple ‘city-killer’ asteroids hitting Earth, including YR4, a 90-meter-wide space rock initially assessed with a one-in-32 chance of striking as early as 2032.
NASA has updated this probability to zero percent, but continues to monitor the asteroid with the James Webb Space Telescope due to a 4 percent chance of a collision with the Moon, according to the Times.
In 2022, NASA conducted a test to deflect potential asteroids, which was successful.
The Double Asteroid Redirection Test (DART) spacecraft was launched into a small moon orbiting an asteroid at a speed of 14,000 miles per hour, successfully changing its trajectory.
Nancy Chabot, a planetary scientist at Johns Hopkins University who led the DART mission, voiced her concerns even after the mission’s success.
The reason for concern is the limited availability of such spacecraft.
“We don’t have [another] DART just lying around. If something like YR4 had been headed towards the Earth, we would not have any way to go and deflect it actively right now,” she stated.
Chabot is also concerned about the uncertainty surrounding these threats.
“We could be prepared for this threat,” she said, referring to YR4. “We could be in very good shape. We need to take those steps to do it. If anything keeps me awake, it’s that.”