A NASA spacecraft is about to crash into an asteroid, destroying the probe and skimming the space rock.
The Double Asteroid Redirect Test (DART) is aimed at an asteroid called Dimorphos, which is orbiting a giant asteroid called Didymos. By crashing into it, NASA hopes to push the smaller space rock into a new orbit closer to its parent asteroid. The impact, scheduled for Monday, is a practice to deflect dangerous asteroids away from our planet.
Dimorphos is 163 meters (535 feet) wide – big enough to destroy a city like New York. This is not a cause for concern, since it is not in Earth’s path, and DART will not change its path through the solar system. But that is the perfect practice for one of the biggest threats in our cosmic neighborhood: asteroids killing the city, clocking in at 140 meters (460 feet) or more.
A really tough deflection method won’t help protect Earth from asteroids if no one sees them coming, though. Experts previously told Insider that NASA would need five to 10 years to build and launch a custom mission to deflect an incoming asteroid. So far, scientists have identified only 40% of the city-killing asteroids that orbit near Earth, according to NASA. No one knows where the rest of them are, or where they are going.
“Obviously, you can’t use any mitigation techniques if you don’t know where the asteroids are,” Amy Mainzer, an astronomer at the University of Arizona, told Insider via email.
In 2005, Congress mandated that NASA catalog 90% of those 140-meter-plus asteroids. Mainzer is working on a space telescope called the Near-Earth Object Surveyor (NEO), which is designed to meet that goal.
NEO Surveyor has progressed slowly through NASA’s mission development process, but recently received a budgetary infusion to propel it toward launch.
“The clock is ticking,” Mainzer previously told Insider. “We really want to get off the ground as quickly as possible.”
Smaller asteroids are already sneaking up on us
Asteroids have already surprised people a few times in recent years.
In 2013, an asteroid the size of a house crashed into the skies over Chelyabinsk, Russia, and exploded. The explosion sent out a shock wave that broke windows, damaged buildings, and injured more than 1,400 people. No one on Earth saw it coming. The same day, a larger asteroid came within 17,000 miles of the planet.
Jim Bridenstine, who served as NASA administrator in the Trump administration, said in 2019 that the agency’s modeling suggested that an event similar to the Chelyabinsk meteor would occur about every 60 years.
But the Chelyabinsk rock was small – about 50 feet wide. In 2019, a 427-foot, “city-killing” space rock flew within 45,000 miles of Earth, and NASA had no warning about that either.
Then in 2020, an asteroid the size of a car passed closer to Earth than any known space rock has ever come without crashing. It missed our planet by about 1,830 miles. Astronomers didn’t know the asteroid was there until about six hours after it hit. No one saw it coming, because it was approaching from the direction of the sun.
Ground-based telescopes can only look at the sky at night, which means they miss almost everything that flies at us from the sun. NEO Surveyor, from its perch in Earth orbit, would be able to spot such space rocks. Since it would use infrared light, it could see asteroids too dark for Earth-based telescopes.
The asteroid spy telescope got a huge budget boost in 2022
Mainzer first submitted the idea for an asteroid-hunting space telescope in 2006. NASA declined to take it on as a mission, funding other projects instead. She also submitted recommendations in 2010 and 2015, but the agency continued.
Surveyor NEO became an official NASA mission in 2019. The project then went into what NASA calls “Phase A” – a phase that focused on design and technology development. Last year, NEO Surveyor underwent a key overhaul and moved into Phase B, allowing Mainzer and her team to begin building prototypes and developing hardware and software.
Then Congress and President Joe Biden approved a budget of $143.2 million for the telescope in 2022. That’s a significant increase from the $28 million the mission received in 2021. NASA aims to launch the mission in the mid-2020s.
Once in orbit, the NEO Surveyor is expected to spend 10 years boosting NASA’s catalog from 40% of city-killing asteroids up to 90%. After that, researchers can move on to smaller classes of asteroids, like the one that surprised Chelyabinsk.
If the DART impact goes according to plan on Monday, NASA will be in a better position to discover any Earth-bound asteroid that the NEO Surveyor might discover.
Read the original article on Business Insider