Planetary Defense Coordination Office, JPL, Astronomical Journal discussed on The Skeptics' Guide to the Universe


Yes. Actually this is just cheered me up a little bit this dude, 'cause we seem to be making some progress in doing at least in doing our due diligence to find asteroids that could potentially be dangerous to us or to earth. This is a new impact in monitoring system. That's now online that could calculate deadly asteroid orbits better than the one that's been calculating for us for the past 20 years. There's a new study describing the system called century two, and it was published in the astronomical journal this past December 1st. So let's first talk about what century one had been doing ever since 2002. So the jet propulsion laboratory JPL, I developed the software almost 20 years ago. What it can do in less than 60 minutes basically, it could accurately tell you the orbit of a newly discovered asteroid for the next 100 years and of course whether it would hit the earth or not. Now, this wasn't a part time job for the software either because we've detected something like 28,000 near earth asteroids NEAs. 28,000 have been found and we find an average of 8 more every day, 3000 a year, every year, every day, 8 more, 8 more, 8 more. And how near is nearby in this context? There's different classes, but near earth is within, you know, relatively near within millions of miles, many millions of miles, which is actually kind of close. If you think about it. So to deal with this clearly scary situation, as I describe it, JPL manages the center for near earth object studies, CN EOS. So now it's their job to run the numbers on every orbit for every near earth asteroid that's discovered. And it does this to support an office, probably the coolest office name ever, NASA's planetary defense coordination office, and I think we've talked about that. Haven't we? I think we talked about that once. I just like my favorite office of all time, right? Planetary defense. It's like that. What's that company? General atomics. It's just such a, such a great 1950s ring to it. So what they do is they provide early detection for potentially hazardous objects. That's PHOs. And okay, so PHOs they're within 5 million miles. If you're within 5 million miles, that's a, which is a type of NEA. But they're clearly much more hazardous because you're only 5 miles 5 million miles away within that. So that means Evan that near earth asteroids, I think are farther than 5 million, obviously. There's planetary defense office also categorizes the PHOs as 30 to 50 meters because that because when you get to that size and that those speeds and the kinetic energy, you can do significant damage. They also this office also tracks and characterizes these PHOs and they issue warnings and stuff like that. So very, very cool. So the center for near earth object studies, they help the planetary defense coordination office and they use this sentry software to assess the asteroid orbits. And they were doing it for years. But the rate of discovery is going to be going up very, very soon. As new and much more powerful survey, telescopes, or as my niche used to call them skeletones. That was such an awesome mispronunciation. So these new powerful telescopes are going to start looking for near earth asteroids and they anticipate an influx of newly discovered asteroids, and they need to be able to keep up with that. And we need to also be even more accurate because it's going to be so many that the chances we could find something that could potentially be nasty. So they came out with century two, which is essentially an upgrade. It's an upgrade to the century software. So century two is obviously like number one in that it can accurately calculate orbits based on gravitational interactions. That's key. You might think that that's what orbits are all about, right? Gravitational interactions. And you'd be mostly right because the asteroid any given asteroid will interact gravitationally mainly with the sun, right? It's interacting with the sun gravitationally, but the orbit of the asteroid could also be impacted by other planets, right, and including the earth, of course, so that so that plays in too. But there are non gravitational interactions. That can happen to the orbit that can impact the orbit. They're not based on gravity at all. And century one could not handle them. And so what do you think that might be, guys? What would impact the orbit that's not gravitational? Solar web thing? Have you kind of it's called the yarkovsky effect. So now imagine an asteroid spinning, which they do. So as that happened, as it's spinning, the side that was heated by the sun eventually spins away from the sun and faces the opposite direction and it cools down. So that infrared energy is released as it cools, and that minute thermal energy acts as a force that that's a kind of like a little mini engine a little bit of thrust that over time can actually change the orbit of an asteroid. Now, day to day, of course, that is negligible. You could just completely discount it fully. But after decades or centuries, it could act your effect can actually make dramatic changes to an orbit, and they're very, very difficult to calculate. So difficult that century one, which had some very slick mathematical algorithms, it couldn't calculate it. But this is what century two will be able to do. Now, do you guys remember Apophis, right? That's probably one of 20 famous. Yeah, one of the most famous asteroids out there. And mainly because for a little while there, we actually weren't sure what if it was going to hit the earth at some point more around 2068 when it came back again after the 2029 was it? So we weren't really sure because we couldn't rule out that impact in 2068, and that's why so many people actually know about Apophis. Now the reason why we couldn't rule it out at that time was mainly because of this yarkovsky effect. They hadn't fully nailed down that what the impact is on the thermal energy that's hitting that asteroid. Of course we do know now we have fully fleshed out the yarkovsky effect on Apophis and we know that Apophis is not going to is not going to hit us for at least well over a hundred years. So don't really don't worry about Apophis. But that's yarkovsky effect right there. That's why people were so scared of a pop is because we hadn't really nailed it yet. So David for Nokia is a navigation engineer JPL..

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