Phil Plait, also known as the “Bad Astronomer,” is a Discover columnist known for making really complicated space stuff (Black holes! White dwarves! Spacetime!) not only totally understandable, but completely fascinating.
Plait made a stop in Portland, Ore. on tour with his latest book, Death from the Skies, to speak at Science Pub, a monthly summit of beer and geeks hosted by Portland’s excellent science museum, OMSI.
Plait’s talk was packed to the gills with both avid Bad Astronomy fans and science-minded folks curious about an astronomer’s take on the end of the world. Here are our favorite asteroid factoids.
1. Objects From Space Hit the Earth… A lot
We see mini-asteroids (meteoroids) crossing paths with Earth quite often, but most of time they fall to the earth as no bigger than a grain of sand or burn up altogether. “It seems like these things are whizzing past us all the time,” Plait says. “That’s because they are.”
2. Asteroids Kind of Look Like Potatoes… Or Dog Bones
According to Phil Plait, it’s a common fact that asteroids often look a lot like potatoes. But Kleopatra, one of Plait’s favorites, is as big as a state and shaped like a dog bone. Kleopatra is actually so big that it has a couple of moons orbiting it as it tumbles through space.
3. Asteroids Can Have Mountains Taller Than Mount Everest
The asteroid known as Vesta boasts a mountain that puts even Everest to shame. And Vesta isn’t the biggest asteroid around, either — that honor goes to Ceres, a dwarf planet that’s 590 miles in diameter.
4. The biggest Asteroid Was Discovered in 1801
We’ve known about Ceres since 1801, when Italian astronomer Giuseppe Piazzi came across the massive body of rock and ice while looking for a star. He initially believed it to be a comet, but now we know Ceres to be much more on par with the size of a small planet.
Plait thinks Armegeddon is up there with the least scientifically accurate movies ever cooked up in Hollywood. InArmageddon, an asteroid headed toward Earth is blown up into two halves. Among the inaccuracies, Plait noted that there’s no asteroid as big as Texas and if there was we’d know about it for well more than 18 days before it was set to impact Earth.
But not all movies go quite so wrong. Plait does like Deep Impact, another film about an asteroid hitting Earth from the same year. Plait thinks the depiction of the asteroid’s impact and its ensuing wildfires and tsunamis is actually “fairly accurate.” That’s terrifying.
6. Even Tiny Asteroids Are Dangerous
The main reason asteroids are dangerous is because they’re hurtling through space so fast. Asteroids fall to Earth at 50 times the speed of a rifle bullet. An asteroid’s impact could well exceed 50 megatons, the impact of the Soviet Union’s AN602 hydrogen bomb and the largest nuclear weapon ever detonated on Earth. You can even play around with an asteroid impact calculator if you’re curious about just how devastating an Earth impact could be.
7. A Group of Scientists Is Taking the End of the World Very, Very Seriously
The B612 foundation is a privately funded organization on a mission to create a “comprehensive, dynamic map” of the inner solar system. The map will identify the current location of asteroids that could pose a threat to Earth and provide data on just how close to Earth they might pass in the future. Worried? You probably should be. You can always donate to the B612 foundation — it might help you sleep at night.
8. Scientists Are Monitoring an Asteroid Headed for Earth in 2029
An asteroid called Apophis is set to pass near the Earth in 2029. Initial calculations gave Apophis a 2.7% chance of striking our planet. Now we know that Apophis’s odds are much, much smaller. But the asteroid could still pass through a half mile-wide area called a “keyhole,” which would change its orbit and up its chances of impacting the Earth on April 13, 2036.
9. How to Fend Off an Asteroid: Whack it, Don’t Blow it up
It sounds like science fiction, but according to Plait, “The idea is now that if you see one of these things coming, you send a probe at it and you smack it.” Even a tiny shift in an asteroid’s velocity and path can make a huge difference if it’s impacted when far enough away in space.
Another option would be harder to pull off: “You could land a rocket on it and push it, but it would be almost impossible to physically land on it, especially for asteroids like Kleopatra that are tumbling.” That asteroid, the one shaped like a dog bone, has an irregular orbit that would make a landing hard to stick.
Learn anything surprising? We certainly did!
This article originally published at Tecca here.