Avoiding Armageddon: Narrowing Down List of Potentially Hazardous Asteroids
Fender Bender
He added that humanity exists in a unique point in its history. Unlike the dinosaurs, humans have the technology to spot a lot of the big objects that pass by our planet. But like the dinosaurs, there’s not much we can do about them. Still, the sooner we learn about potentially dangerous asteroids, the better, Fuentes-Muñoz said.
“Making a small deflection decades in advance is way more powerful than trying to deflect an asteroid a few years or months in advance.”
Predicting where an asteroid will be hundreds of years into the future, however, gets tricky. A number of factors, from the pull of Venus’ gravity to heat from the sun, nudge asteroids in their orbits, and those minor changes can add up over time. Fuentes-Muñoz and his colleagues wanted to see if they could narrow down those uncertainties. The team included David Farnocchia and Ryan Park of NASA’s Jet Propulsion Laboratory in California and Daniel Scheeres, distinguished professor of aerospace engineering sciences at CU Boulder.
Fuentes-Muñoz explained that you can think about an asteroid impact like a traffic collision.
For two cars to crash, they first have to be traveling through the same intersection. They also have to reach that intersection at the exact same time.
In the new study, the researchers used a series of computer simulations to identify when the orbits of near-Earth asteroids might overlap with our own path around the sun—what scientists call the minimum orbit intersection distance (MOID). They then tried to identify the asteroids with timings that remain hard to predict. In other words, is there a possibility, even a small one, that these bodies could be in the same place and the same time as Earth?
7482 (1994 PC1)
In what might seem like good news for people, the list of candidates that could meet both criteria for an impact seems to be short. But, the researchers reported, a few asteroids stand out.
7482 (1994 PC1) is among them. This rocky body was first seen in 1974 and stretches about two-thirds of a mile from end to end. Most of the asteroids the team studied will likely cross Earth’s orbit for only short windows of time—passing through briefly, then zipping away. 7482 (1994 PC1), however, could remain in Earth’s close vicinity for most of the coming millennium.
Don’t worry yet, Fuentes-Muñoz said: “We need more information to rule out an impact, but we still think it’s unlikely to happen.”
He added that the more information scientists gather about asteroids like this one, the more certain they can be about just how likely a collision could be in humanity’s future.
“When I tell people about my research, the most common thing I get is, ‘Will you let us know if something’s going to happen?’” Fuentes-Muñoz said. “‘Yeah, I’ll let you know.’”
Daniel Strain is a science writer at the University of Colorado Boulder. The article was first published on the University of Colorado Boulder website.
