Turika Bose: What if a giant asteroid starts hurtling toward Earth? Are we all headed for imminent doom, like the dinosaurs some 66 million years ago?
NASA: 4-3-2-1. Oh my God. Oh wow. Awaiting individual confirmation…and impact! In the name of defending the Earth, let humanity win!
Bose: (No pun intended) Hailed as a smashing success, more than five studies in the scientific journal Nature get to the heart of how our celestial gut punch worked. .
NASA: What a moment. There are few words that can capture this moment. beautiful to look at.
Bose: Hey Lee.
Claim: Hi Turik.
Claim: right. Ideally, we’ll actually talk right away, but it’s as easy as playing billiards. Shoot a billiard ball into another billiard ball and the target ball will fly. The more momentum you can transfer, the more movement you get. That’s why I want to hit near the dead center. And in the case of DART, it targeted the solar “primary” side of Demorphos and struck at speeds in excess of 14,000 miles per hour.That’s about three-quarters the speed of General Zod’s spaceship in Zack Snyder’s Man of Steel.
General Zod: now. Kneel before Zod.
Bose: Um, ok. Now tell me about the two asteroids.
Lee: Oh yes, two asteroids. Dimorphos is an asteroid of the larger asteroid Didymos. That’s why Dimorphos is sometimes called “Didymoon”. This helps measure the effectiveness of DART. Dimorphos are a bit like the second hand on a clock, while Didymos are the hour hand or clock itself. You can easily see small changes by observing how small objects move.
Bose: Ok, it’s pretty big.
Claim: But for those of us steeped in modern times, I’d say it’s about twice the size of a standard soccer field and weighs an estimated 11 billion pounds.
Bose: Wow.
Claim: DART, on the other hand, is a mere 1260-pound spacecraft, about the size and weight of a dairy cow. The fact that DART made a dent at all actually comes down to the high speed effects we already mentioned, which is 14,000 miles per hour. And all this after a deep space voyage to the impact point, more than seven million miles from Earth.
Bose: Like a dairy cow crashing into the Great Pyramid?
Cow: mu [splat.]
Claim: Basic. It becomes a mess.
Bose: teeth. Now let’s get back to science. More information has been found to help astronomers understand why the crash was so successful. What are the new details about this effect that have been discovered, and what surprised scientists? What was NASA’s original purpose?
Lee: That’s a great question Turika. And the answer, surprisingly, was how well it worked: NASA’s official success criteria was to shift Demorphos’ orbit by just 73 seconds. Initial predictions predicted that, for example, a real billiard ball made entirely of solid rock would be pushed around by a DART for about 7 minutes. Instead, it went to 33, 33 minutes.
Bose: Wow!
Lee: yes!andHis difference is that Dimorphos is not a billiard ball. A pile of loosely bound rubble. As the DART closing image showed. So when the DART hit, it released a huge plume containing over 2 million pounds of material, essentially giving Didymo a recoil. It’s like a shotgun kick.
Bose: Oh wow. Well, that really helps me visualize it a bit more. So DART is this $330 million golf cart size spacecraft that was completely obliterated by this asteroid in just a few microseconds. Scientists seemed pretty confident this was a success — but what else is needed to keep us from being wiped out by more dangerous asteroids heading for Earth? Is not it?
Lee: Great question, Turika. What we really need is better situational awareness. How many of these objects are there? What are they made of? where are they?
Bose: Well, who is working on it now?
All kinds of people. The key is to get a catalog of objects of different sizes, different orbits, and even what they’re made of, and figure out which ones are the most threatening. As for , Hera is the first dimension. This is a project of the European Space Agency. It is named after the Greek goddess who married Zeus, the queen of the gods.
Bose: Queen!
Claim: queen, queen. Well, Hera was originally scheduled to arrive at Dimorphus of Didymus around the same time as DART. But instead, due to delays, it is currently not expected to launch until late next year, arriving in 2026. Now, there is something else to mention. One of his projects I’m excited about is his NEO Surveyor for NASA, the Near Earth Objects Surveyor Space Telescope. This is an infrared space telescope, presumably he will launch in 2028. Creating a catalog of this object would be a huge step towards better understanding what is really there and what the threat is. On the ground there is something similar to the Vera C. Rubin Observatory. One of the very important things about this mission is doing the same kind of work from the ground. These full panoramic, high-resolution sky images are taken multiple times per night to create a near-high-resolution sky movie for each night. And you can see tiny dots of light moving around, and some of them could be Earth-threatening asteroids.
Bose: Oh, it’s named after Vera Rubin, isn’t it?
Billings. That’s right. I think you are one of the discoverers of dark matter, right?
Bose: yeah yeah We also know that researchers, with the help of amateur astronomers, continue to examine the DART data to find out more about the physics, geology, and chemistry of these two asteroids. Mr. Lee, what are you most looking forward to in the near future?
Claim: To be honest, I thought Didymus and Dimorphus were a little finished and dusted off. We’ve already hit space rock and seen what happened. I am interested in obtaining this catalog. I’m curious to learn more about the properties of different asteroids, as they may not be the pile of rubble that comes to us every time. What if it was a big ball of metal? What if it was made of ice? don’t know.
Bose: that’s true.
Claim: The answer is obviously to hit more cows into the pyramids, send out more missions of this kind, and figure out what happens when you really hit the bard in the solar system. I have to say it’s not enough to save us. There are many situations where something can hit us hard and DART won’t save us.
Bose: I’m sure you can rest easy.
Claim: please.
Bose: Thanks for listening to Science, Quickly.I’m Turika Bose
Billings — and I’m Lee Billings.
Bose: Science is produced rapidly by me, Tulika Bose, Jeffrey DelViscio, and Kelso Harper. Don’t forget to subscribe to Scientific American wherever you can get the podcast.
Claim: Also, visit Scientific American.com for more in-depth scientific news and analysis.
Claim: Also, visit Scientific American.com for more in-depth scientific news and analysis.
