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00:00:10so this next set is finishing up we'll have some new data here pretty quick
00:00:16potentially hazardous asteroids can show up anywhere in the night sky at any time so we
00:00:22were up here for 12 to 13 hours sometimes making decisions about the objects we're seeing if they're
00:00:28real or if they're just noise in the background and so the odds of finding an asteroid are going
00:00:41to increase as we move toward the toward the east
00:01:09oh this might be something oh you guys look at that
00:01:14based off these four images this is a new brand new near-earth asteroid we got one no like i
00:01:20didn't
00:01:20think that was gonna happen we got like yeah no it's brand new i just got the notice back from
00:01:24uh from the minor planet center that they published it so there it is bam live this is actually a
00:01:30big
00:01:30rock too right now it is absolutely a potentially hazardous object if you guys were going to be
00:01:35here for a discovery a pha is definitely what you want yeah this is a big rock yeah it is
00:01:41nominally about 230 meters in diameter which is quite large and it's minimum orbit intersection
00:01:50distance with earth which means how close it comes to the earth's path in the earth's orbit
00:01:56is between us and the moon it's only about 150 000 kilometers away which is a significant pha a pha
00:02:04like this only comes up a couple times per year so so these are the ones we want
00:02:13yeah that's a nice one
00:02:44it's a nice one
00:02:44so
00:02:44from the moon
00:03:12Transcription by CastingWords
00:03:14Three fragments are scheduled to hit the planet
00:03:17Will slam into the same area, the same spot on the planet Jupiter
00:03:22About 1993 we learned that there was a comet heading for Jupiter
00:03:26Comet Shoemaker-Levy 9 was a comet that was discovered by Eugene and Carolyn Shoemaker and David Levy
00:03:34It was shown to be broken up into a bunch of pieces
00:03:36They traced back the orbit, this thing had gone by Jupiter and got disrupted
00:03:40And then they tracked the orbit forward and found out these are going to hit Jupiter
00:03:45And that got everyone excited
00:03:46It's really the first time that these impacts have been observed
00:03:49Impacts were very important in the formation of everything
00:03:54We could observe an impact on another planet
00:03:56Scientists still don't know what they're going to see tonight
00:03:59But they do know that they've come to the best place in the world to see it
00:04:04The whole world community, scientific community was preparing to observe these events
00:04:08Any telescopes that could observe the impacts did
00:04:11Many, many ground-based telescopes
00:04:13The Hubble Space Telescope
00:04:14All of the images from Hubble that went on the web
00:04:17Or suddenly got everyone's attention
00:04:19Which was a real key to many of the scientific results
00:04:22Also Galileo
00:04:24Which was on the way to Jupiter at the time
00:04:26The NASA Infrared Telescope Facility had a campaign dedicated to observing Shoemaker-Levy
00:04:32This observing run for the Shoemaker-Levy 9 impacts
00:04:35That was my first observing run ever
00:04:38We're starting tonight with the near-infrared spectrometer
00:04:41God, that's gorgeous
00:04:42We were seeing something pop up on the screen
00:04:44It was really shouting
00:04:47Literally dancing about it
00:04:48And we saw this bright thing just light up
00:04:52And it was like, yes, we did it
00:04:54We were all like kids in a candy store, I guess
00:04:56A lot of the energy we saw wasn't just the impact itself
00:04:59But it was sort of the splashback
00:05:01And when those pieces plowed into the atmosphere
00:05:03They brought up big plumes of material that rained back down on the upper part of the atmosphere
00:05:09We were able to measure changes in the upper atmosphere of Jupiter
00:05:12It taught us a great deal about how impacts take place
00:05:16Scientists say if a fragment the same size hit Earth
00:05:20It would leave a crater the size of Rhode Island
00:05:24It was one of those wake-up calls that not only impacts something that happened in the past
00:05:30But they're happening now in our solar system
00:05:33And here it is, this awakening
00:05:35It kind of precipitated this NASA Planetary Defense Coordination Office
00:05:40To make sure to find the asteroids that come close to Earth
00:05:44And the comets that come close to Earth
00:05:46Get them catalogued
00:05:47Figure out where they've been
00:05:48And where they're going to be in the future
00:05:50Just so we understand
00:05:51Are we at risk of being impacted on the Earth?
00:05:54So that's a big component of what NASA does now
00:05:57It has planetary defense
00:05:58To find potential impacts for the Earth and protecting it
00:06:18Let's go back to Senator Cruz's question
00:06:21What would an asteroid that is a kilometer in diameter
00:06:26What would it do if it hit the Earth?
00:06:29That is likely to end human civilization
00:06:38The impacts of Comet Shoemaker-Levy 9 with Jupiter in 1994
00:06:43That showed us that, you know what?
00:06:45Impacts are still happening in the solar system today
00:06:49That really spurred some interest on the part of the Congress
00:06:52NASA was tasked by Congress in 1998
00:06:56To catalog 90% of all the large near-Earth objects
00:07:00So those that are one kilometer or more in size
00:07:05Those objects are big enough to cause what we would call
00:07:07Truly global devastation
00:07:09Meaning that they could cause global extinction events
00:07:11The good news is that we found more than about 95% of them
00:07:14The catalog includes almost 900 asteroids
00:07:18One kilometer or larger in size
00:07:20That said, none of these known large NEOs
00:07:25Pose any threat of impact to the Earth within the next 100 years
00:07:31And then eventually in 2005
00:07:33That direction from Congress to NASA was set
00:07:37To find the population of asteroids that are 140 meters and larger in size
00:07:42That could do regional damage should it impact Earth
00:07:46A city killer
00:07:48Now the picture is not so rosy
00:07:49We know of about 40% of those objects today
00:07:52Today we do not have a complete inventory of all the possible impactors
00:07:59And that is something that NASA
00:08:01And the worldwide planetary defense community has been endeavoring to do
00:08:05Well here at NASA, what I lead is the Planetary Defense Coordination Office
00:08:09We are helping to coordinate efforts not only in the United States
00:08:14And across the U.S. agencies
00:08:16But also around the world
00:08:18Finding asteroids, tracking them, calculating their orbits
00:08:23Figuring out where they're going to be in the future
00:08:25Studying their physical properties
00:08:27And then you get that information you might need
00:08:30In the event an impact threat is discovered
00:08:33We have discovered more than 30,000 near-Earth objects so far
00:08:36And we are discovering, you know, hundreds, you know, every year
00:08:41But we haven't found them all
00:08:43So that's really the big question
00:08:44There's almost certainly a decent sized asteroid out there
00:08:48That is going to pose an impact threat to the planet
00:08:51We're just trying to find it right now
00:09:03So the way we approach finding near-Earth objects
00:09:06Is basically just to make a short movie of the night sky
00:09:09That consists of four frames
00:09:12And then our software will pick out objects
00:09:14That are moving inside of the four frames
00:09:16And we have to identify if they are real
00:09:18Or if they are false detections
00:09:22I first started hunting asteroids in my backyard
00:09:24And I just had the hope of maybe discovering one
00:09:28And when that happened, it was a very special moment in my life
00:09:31My interest in astronomy started at a fairly young age
00:09:34I remember as a kid seeing comet Hellbop in the sky from southern Utah
00:09:38It was really a spectacular sight as a child
00:09:41And just trying to wrap my mind around what I was looking at was difficult
00:09:46This is one area of science where discoveries are still happening
00:09:50On a nightly basis
00:09:51And it's really a neat feeling to step into that
00:09:55Where you can be sitting at a telescope at night
00:09:57And discover a new minor planet that's in orbit around the sun
00:10:01That nobody has ever seen before
00:10:03It's a special thing
00:10:04And I think that's what draws a lot of people into this business
00:10:12The first order of planetary defense is finding the asteroids
00:10:15And so one aspect of the program is funding institutions with telescopes
00:10:20That can image wide swaths of the sky
00:10:23To be able to look at the starry background
00:10:27And look for objects moving with respect to the stars
00:10:30To see if there's something there that we haven't seen before
00:10:32This is the whole sky
00:10:33That's an all-sky camera
00:10:34So you can see this is a live video feed from the end of the telescope
00:10:37And you can make out the Milky Way right here
00:10:39And this is the size of the images we're taking right now
00:10:42And then we subtract the known objects and the stars from those images
00:10:46And then we look for moving targets
00:10:48The object is moving because it's closer to the Earth than the background star
00:10:52I can tell this first one is a star
00:10:53You can see that that object stays there
00:10:55So if I load up a catalog image, which is a very old image
00:10:58You can see that first hit is actually a star
00:11:01That one's actually a star
00:11:02Those moving targets are going to be asteroids that are in orbit around the sun
00:11:06So that's a known asteroid
00:11:07It comes up green
00:11:08And it has the designation above it
00:11:10And oftentimes they're new, we've never seen them before
00:11:12So what we have here is a near-Earth asteroid that is likely brand new
00:11:16And I can already tell that it's not coming up in any of the known databases
00:11:20And then what you have to do is go and identify
00:11:23Whether it's a known asteroid or a new asteroid
00:11:25So that's the next step
00:11:26When the asteroid is first discovered
00:11:28We submit the information almost immediately
00:11:30To the Minor Planet Center at Harvard
00:11:32And we are going to send this data off in real time here
00:11:36The temporary designation we're going to assign to it
00:11:38The date and the time and the location on the sky that it was located
00:11:42And then it's approximate visual magnitude
00:11:45I'm going to report it as a brand new near-Earth object candidate
00:11:50It's important to turn that information around quickly
00:11:53The different survey telescopes quickly feed those position measurements
00:11:57To the Minor Planet Center
00:11:58Which is the internationally recognized repository
00:12:01For position measurements of small bodies throughout the solar system
00:12:09Minor Planet Center is, I like to think, the link between the astronomy community
00:12:13And everything that comes after that in planetary defense
00:12:17My name is Federica Spoto
00:12:19And I'm the project scientist of the Minor Planet Center
00:12:21So part of the role of the Minor Planet Center
00:12:24Is to actually distinguish what is known and what is not known
00:12:29We keep all the observations and all the orbits of the objects
00:12:32So we don't see the image, we just see the spines
00:12:35And those represent the different positions of the object moving
00:12:38And so it tells you very accurately the time of the observations
00:12:41And then the position
00:12:42So once we have the position and the time, we can get the orbit
00:12:45So all the data comes in from everyone, gets consolidated there
00:12:49So we have a common catalog that we are working from
00:12:53An archive of everything that is known and everything that is not known
00:12:58The cool thing about the Minor Planet Center is that everything we do is public
00:13:02So as soon as we receive the observations, the observations goes out
00:13:05That information can all be rolled up there and available for other observatories to see them
00:13:12And then go get additional observations so that there is enough information to get in orbit
00:13:17And anyone can then access that data to track these objects down
00:13:21And help us determine if they are going to be an impact risk in the future
00:13:24Once we find an asteroid and we've got an orbit for it
00:13:27The next logical question is, is it going to hit the Earth?
00:13:31Fortunately, there's a group here at the Jet Propulsion Laboratory
00:13:34Called the Center for Near-Earth Object Studies, or CNEOs for short
00:13:37That is tasked with doing exactly this
00:13:43They assess the hazard potential of this newly discovered near-Earth object
00:13:48And they do orbit determination to see both short-term and way out into the future
00:13:54100 years into the future, could any of those pose an impact threat?
00:13:57My name is Ryan Park and I'm the supervisor of the Solar System Dynamics Group
00:14:01At the Jet Propulsion Laboratory
00:14:02And I'm also serving as the project manager for the Center for Near-Earth Object Studies
00:14:07So to date, we maintain about a little over 1.3 million objects
00:14:11Most of them being asteroids
00:14:13We predict the motion of all known asteroids
00:14:16And we process the entire data set from the Minor Planet Center
00:14:19To predict and reconstruct the orbit of the asteroids
00:14:22So that we can perform statistical assessment of the potential Earth's impact
00:14:27Yeah, so what we do is we process the astrometry collected by ground-based observers
00:14:33And we feed those through what we call the orbit termination process
00:14:36To get the orbit of the asteroid as a function of time
00:14:40So we can propagate backwards, forwards, and figure out where the asteroid is in real time
00:14:45So this basically catalogs all the potentially hazardous asteroids that might come close to the Earth
00:14:51And we document the probability of potential Earth's impact
00:14:55And if it were to hit the Earth with certain probability
00:14:58When is it going to be and where is it going to be?
00:15:00And we do this for the next hundred years
00:15:03And assess whether it's going to be hitting the Earth
00:15:05And if so, with what probability?
00:15:08And that information gets shared with the CNews website
00:15:10As well as with the entire world
00:15:14This data gets disseminated immediately to many different organizations
00:15:18And NASA's Center for Near-Earth Object Studies
00:15:22Runs watchdogs that are constantly ingesting this data
00:15:26And calculating the odds of an impact in the near future
00:15:30And if they find that this object has any probability of hitting the Earth in the near future
00:15:34We will get an alert on our systems within about 10 or 15 minutes
00:15:38And then when people start receiving this type of, like, warning
00:15:42Then there's a huge community of astronomers that start observing it
00:15:46From all around the globe
00:15:48As the Earth rotates and nighttime falls across Asia or Europe
00:15:52And so we start getting observations from all over the world at every time
00:15:56And we start processing them really quickly
00:15:58It's a very smooth-running machine
00:16:05It transcends boundaries of countries
00:16:08Asteroids don't care about international boundaries
00:16:11It doesn't matter where the asteroid impacts
00:16:14It affects, you know, the entire humanity
00:16:16In fact, anything alive on the Earth
00:16:18It transcends basically anything except what makes us human
00:16:21And what it means to help discover and protect the planet
00:16:26From a hazardous asteroid that might be incoming
00:16:29Yeah, I'm really proud of it, I would say
00:16:32It's like, yeah
00:16:33I'm proud and I'm proud that I'm working on something
00:16:35That is actually very useful for the community
00:16:37Like, through our planetary defense
00:16:39We're also like, we do everything so that we can help the community
00:16:45It was a great honor to have an asteroid named after me
00:16:50So, there's Ryan Park Asteroids
00:16:52I mean, this was a huge deal for me
00:16:55I mean, this basically led me to believe that I'm making some contribution to the field
00:17:00We didn't even know asteroids existed 200 years ago
00:17:04And it's only been in the last few decades that we even had the technology to be able to detect
00:17:10these things
00:17:10So, yeah, I might be referred to as the father of planetary defense
00:17:17I created the term, perhaps
00:17:20But it is only because I, you know, stand on the shoulders of those asteroid hunters before me
00:17:27That we are now able to protect the world from asteroid impact
00:17:35So, this object has already been ingested by the Center for Near-Earth Object Study's scout watchdog
00:17:42Right off the bat, it tells us that the probability this is a near-Earth object is already 100%
00:17:47And the probability it is a potentially hazardous asteroid is 67%
00:17:51There is no real impact rating or probability
00:17:56So, it's not currently a threat
00:17:58But long term, after the arc is extended
00:18:01And we have a better idea of the orbit of this object
00:18:04This might be a brand new, unknown, potentially hazardous asteroid
00:18:19So, finding asteroids, that's probably the most important part of planetary defense
00:18:23Or the fundamental part of planetary defense
00:18:26But it doesn't help to see an asteroid if you don't have enough information to know where it's going to
00:18:31be in the future
00:18:32You can't do anything about them unless you find them and know where they're going
00:18:37That means the race is on to try to figure out how can we get more data
00:18:40Can we get more exposures of it so that we can figure out which way it's actually going
00:18:44And then eventually, get a really good orbit for it so that we can predict far into the future where
00:18:49it's going to go
00:18:50Especially with respect to the Earth
00:18:51So, then there are telescopes that go zero in on those initial observations by the surveys
00:18:57And they get even more measurements of those positions
00:19:00My name is Cassandra Lejoli
00:19:03Spacewatch is a follow-up survey essentially
00:19:06So, the telescope behind me is a 0.9 meter telescope that we use to follow up near-Earth objects
00:19:11When they're first discovered, they have very short orbital arcs
00:19:15So, they have very imprecise orbits
00:19:18And so, if we follow them up, we get a better orbit to determine if there's a higher chance of
00:19:24them hitting the Earth or not
00:19:26So, these are the type of images that we get back from the telescope
00:19:30And so, you can see that our asteroid is essentially a dot that's moving
00:19:35And then the stars look like long lines because of how we track on the asteroid and not on the
00:19:41stars
00:19:43When an asteroid is first discovered, the Minor Planet Center is able to calculate
00:19:48kind of a location around the sky where it should be
00:19:51So, we already have an idea of how the asteroid is going to be moving
00:19:55So, we take that assumed motion and move with it
00:20:01So, my typical day or night, I guess
00:20:05We typically observe for four to six nights straight
00:20:09And we come up to the mountain and we have dorms up here
00:20:12So, we stay up here the whole time we're observing
00:20:17And what happens is that we'll open the two telescopes
00:20:19We then have on our computers kind of a list of all the objects we can see that needs follow
00:20:25-up right away
00:20:26There's a few objects we can choose here
00:20:28I like to go for virtual impactors because they're top of our list
00:20:31They have a probability of hitting us
00:20:34We'll pick the best targets for the night
00:20:36Some of them come in as we're observing overnight
00:20:39If they're newly discovered and they need follow-up then
00:20:41So, let's say I want to go for this object
00:20:43What I would do is I would accept it in my queue
00:20:46And then I would accept the value and send it for recovery
00:20:49What that would do is that would move the telescope
00:20:52So, we get three images of it to see it move
00:20:55And to see what speeds it move
00:20:57And then we measure its location on the sky
00:21:01That is the measurement we report back to the Minor Planet Center
00:21:05Well, that's an asteroid
00:21:08Right here
00:21:09It's really cool when you're looking like at an image from the sky
00:21:13And you see a moving dot
00:21:15Like every time I find that moving asteroid
00:21:18I'm excited by it because it means you found it
00:21:21Like you found a thing in space that is moving
00:21:25Like it's right there on my image
00:21:27I can see it
00:21:29So, right there is our object and it's moving right there
00:21:32So, the first image is in the star
00:21:33So, we can't measure that
00:21:35But then the second and third image are right there
00:21:38So, we can actually measure those
00:21:40And that new measurement then helps better predict the orbit fit
00:21:44And thus better predict where it would be in the sky
00:21:47Next time someone needs to observe it to follow it up
00:21:49The most important thing is always get more data
00:21:52Because the more data you get the better you are
00:21:55At finding the orbit and know where the object is
00:21:57And if you take another image a little bit further
00:21:59You can then put another data point
00:22:01And then you can keep tracing that orbit around
00:22:04As you collect more observations
00:22:06The orbit of the asteroid in question will get better and better
00:22:10I really like that I'm protecting the planet
00:22:13And yes, I'm not the one that's like with a cape pushing the asteroid away
00:22:17That's not what I do
00:22:18In some ways, like my little contribution might help
00:22:22Not just myself, but someone in the future
00:22:25And I think it's very important to do that
00:22:34So, last night while surveying in an area of the sky
00:22:37Where we don't typically find a lot of objects
00:22:39I discovered an object that had to be fairly large to be visible
00:22:43For where it was in the sky
00:22:44So, here is the asteroid that Catalina Sky Survey discovered a few days ago
00:22:50And we can also tell that it's a pretty big object
00:22:53The asteroid has to be observed for many weeks and months into the future
00:22:57So, we can extend that data arc
00:22:59So, the orbit of that potentially hazardous asteroid is known into the future
00:23:04So, the discovery arc of the asteroid consists of just four points of data over 20 minutes
00:23:09And that is a really small snapshot of the entire orbit of the asteroid
00:23:14And it was able to be followed up all around the globe so that we didn't lose that asteroid
00:23:18And you can see that it's been followed up by several different telescopes right here
00:23:22So, the arc length means it's been observed for more than a day
00:23:25So, that is where it comes the closest to intersecting the Earth's orbit
00:23:30And telescopes around the world will continue taking observations of this object
00:23:34To keep seeing if it has a potential of hitting the Earth or not
00:23:48Well, at the current rate of detection of near-Earth asteroids
00:23:52It's going to take us about another 30 years before we have this catalog that we've been tasked by Congress
00:23:59to do
00:24:00We've only discovered less than 40% of the 90% of the object we need to discover
00:24:05Finding the asteroids isn't something that can just happen overnight
00:24:08Because telescopes can only see so far away or they can only see so faint into what they might be
00:24:16looking for out there
00:24:17Ground-based telescopes are kind of limited to looking at night away from the Sun
00:24:21And we have to wait for the solar system to bring asteroids around
00:24:26The Earth is traveling around the Sun, the asteroids are traveling around the Sun
00:24:30And so, it isn't possible to see the entire solar system at the same time
00:24:35It's hard to find asteroids because relative to the size of the Earth and the distances within the inner solar
00:24:40system
00:24:41They don't get bright enough to spot until they get closer to the planet
00:24:45One of the tricky things with searching for near-Earth objects is that some of them are extremely dark
00:24:50They're darker than lumps of coal
00:24:53And that means that when we look for them using the sunlight that reflects off their surfaces
00:24:57They're actually hard to spot because they're dim and faint
00:25:00There are asteroids out there that are very darkly colored and don't reflect a lot of light from the Sun
00:25:06And so, they're difficult for the telescopes on the ground to discover
00:25:10That are looking at the light that we can see with our eyes
00:25:14So, how do you overcome this?
00:25:16We have to go into space
00:25:17We have to use different wavelengths and reflected light
00:25:20All the telescopes on the Earth that are currently finding near-Earth asteroids are discovering in the visible wavelength
00:25:26They are primarily looking at light reflected by the asteroid from the Sun
00:25:31The sunlight hits the asteroid, reflects just like everything in the solar system
00:25:35One way we can kind of get around this is instead of looking at the sunlight reflecting off their surfaces
00:25:40We can use the heat that they emit to search for them
00:25:43If we have a heat-seeking telescope working at infrared wavelengths
00:25:47Even the dark objects just pop right out
00:25:49They stick out very brightly because they've got a lot of heat that they re-radiate
00:25:53And we can see that energy
00:25:55Once you go into space, you're away from the heat of the Earth
00:25:58You can start looking at the infrared wavelengths
00:26:00Because in the infrared wavelengths, asteroids have more energy being given out
00:26:06Because a lot of them are darker
00:26:08So, they absorb the radiation in the daytime
00:26:10And in the nighttime, they re-radiate
00:26:13So, they're very bright
00:26:14You don't need that big a telescope in space to detect the asteroids that you would from the Earth using
00:26:20visible light
00:26:21And Near-Earth Object Surveyor is one such telescope
00:26:24The Near-Earth Object Surveyor mission, or NEO Surveyor for short, NEO Surveyor
00:26:28Is a space telescope that we're building
00:26:30That's designed to detect, track, and characterize asteroids and comets that have the potential to get close to the Earth
00:26:37It'll also be positioned in such a way that it can survey closer to the Sun than the telescopes on
00:26:43the ground
00:26:44Because of this nice, tall sunshade, we can actually point relatively close to the Sun
00:26:48And that lets us look far across the Solar System
00:26:51So that we can spot the asteroids when they're far away from us
00:26:54So that, working in concert with the telescopes on the ground
00:26:57Is going to really accelerate those objects getting into the catalog
00:27:02With NEO Surveyor, we should be able to see something like a few hundred thousand new Near-Earth Objects
00:27:08Over the course of its survey
00:27:09We expect the numbers will increase by somewhere between a factor of 5 to 10 in the next decade
00:27:16They're going to give us lots of data
00:27:18And they're going to require from us to have different tools ready to handle the data in the best way
00:27:23we can
00:27:23This increased rate of detection in the number of observations that will be coming into the Minor Planet Center
00:27:29Does require the Minor Planet Center to be able to process things at a more rapid rate
00:27:35And we're ready for it
00:27:36And hopefully, that's going to tell us a lot about the largest objects in the populations
00:27:41The ones that are really, truly large
00:27:42That have the potential for a large amount of ground damage if they were to impact the Earth
00:27:54This is still kind of a golden age of discovery for asteroids
00:27:58One day in the future, we will have found all of these objects
00:28:01And this period of asteroid discovery will come to a close for the most part
00:28:05At least the rocks that could pose a significant threat to the Earth
00:28:08Will eventually all be cataloged, characterized, and either dealt with or removed from the risk lists
00:28:14Any piece that you can do to help, you should do it
00:28:17And I think that's really important
00:28:19You don't have to be a planetary scientist to go into planetary defense
00:28:24It's just an amazing thing to take science and apply it in such a way that it affects people's everyday
00:28:32lives
00:28:32Well, for me, it's very personally satisfying to be involved in an effort like this
00:28:39I found my role in life, so to speak
00:28:41So for me, it is very personal because I have a chance
00:28:46I'm fortunate enough to contribute, you know, using science
00:28:49To protect the humanity, you know, to protect the planet for that matter, you know
00:28:53And everything that is on it, because we only have one Earth
00:29:09The explosion of a meteor over Russia last month injured 1,500 people
00:29:13The recent meteorite that hit the Russian Urals with the force of an atomic bomb
00:29:18Was a stark wake-up call regarding threats from space
00:29:22When the asteroid passed through the Earth's atmosphere, it did so at a really high speed
00:29:26Something like 40,000 miles an hour
00:29:29It had an explosive energy about 25 times the bomb used in Hiroshima
00:29:33Or about 470 kilotons of TNT
00:29:37It did cause a massive shockwave that shattered windows all over the city
00:29:48This much smaller meteorite was not observed prior to its entry into the atmosphere
00:29:53The Chelyabinsk impact came from the direction of the sun
00:29:56It was on a very difficult trajectory for us to be able to see from ground-based telescopes
00:30:01Scientists testified about how these objects are tracked and how those risks can be minimized
00:30:07As we were reminded a couple of weeks ago, the Earth is sometimes hit by asteroids
00:30:12Impacts have happened, and they will happen in the future
00:30:15That asteroid was only about 18 meters across
00:30:17That would fit inside this room, roughly
00:30:19This asteroid never made a big impact crater on the ground
00:30:22That's because it wasn't big enough originally to make it to the ground fully intact
00:30:27So the impacts of air bursts are different from an impact that is physically going to touch the ground
00:30:33As the asteroid slammed through the Earth's atmosphere, it was like hitting a brick wall
00:30:36And it just pulverized it into a million little pieces, like this one here
00:30:40Even just from that 20 meter asteroid disintegrating in Earth's atmosphere
00:30:44The shockwave from that, that did damage
00:30:47The inside of the asteroid is stony, it looks like an ordinary rock
00:30:52We need to know more about these objects that could impact us
00:30:57How big is it?
00:30:58What's it made out of?
00:30:59How does it spin?
00:31:00How much potential for damage it might pose on the ground?
00:31:03The Earth has been bombarded by asteroids in its history
00:31:05And it will be hit by asteroids again
00:31:07The questions that we're trying to answer in planetary defense
00:31:11Are when, where, and which rock is going to do it?
00:31:35So what we have here is a diversity of meteorites
00:31:39Where they range from stony meteorites, like the ones you see here
00:31:43A great example of that is Chelyabinsk, which fell in Russia in 2013
00:31:48We want to understand the threat that is coming towards us
00:31:52Part of understanding the threat is understanding the capabilities
00:31:56Oftentimes, the physical makeup of an object tells us about its capability
00:32:01Its impact potential
00:32:02What can it do on the Earth?
00:32:04So studying the composition tells us whether it's an iron
00:32:08Whether it's stones, or stony iron, or carbonaceous
00:32:12A weak object, which has low density, is not going to make it into the atmosphere
00:32:16And intact onto the Earth, okay?
00:32:19So you would have an air burst, for example
00:32:21Whereas if you have a really dense object, like this iron meteorite
00:32:24It'll punch right through the atmosphere, even if it's a small object
00:32:27And then it will create a crater, like the meteor crater we see in Arizona
00:32:33So what do these meteorite tell us, right?
00:32:36Why do we need to characterize these objects?
00:32:37So by understanding the composition, we can figure out
00:32:41What is the mitigation mechanism we're going to use?
00:32:43Because the tools we would use vary vastly depending upon what they're made of
00:32:53To understand what asteroids are, you have to go back to kind of the beginning of our solar system
00:32:58Asteroids are rocky bodies that are kind of leftover fragments from when our solar system first formed a long time
00:33:04ago
00:33:04More than 4 billion years ago
00:33:06Major planets formed when the first solids condensed out of the solar nebula
00:33:09These solids slowly coalesced, you know, came together
00:33:13Eventually to form what you call as planetesimals
00:33:15These are objects that are, you know, a few tens to a few hundred kilometers across
00:33:19And you had, you know, internal heat, you know, that led to what you call as differentiation
00:33:24They'll have a core, a mantle, and a crust
00:33:26So these iron meteorites we see here represent the cores of those planetesimals
00:33:33So we believe that there were more than a hundred planetesimals that differentiated between the orbits of Mars and Jupiter
00:33:40But most of these planetesimals were destroyed catastrophically due to impacts over the next few hundred million years
00:33:47And what we see now in the asteroid belt are remnants of those catastrophic destructions
00:33:53Most of the material that made up our solar system kind of got swept up into the sun and to
00:33:58the individual planets
00:33:59But not all of it
00:34:00You know, it's kind of like shattering a plate on the floor
00:34:02You know, you have a few big pieces, but lots and lots of small pieces
00:34:07So asteroids are kind of those leftovers of the formation of the solar system
00:34:11A lot of them keep their distance very nicely in the asteroid belt between the orbits of Mars and Jupiter
00:34:17But some of them over time, because of being tweaked by the gravitational pull of Jupiter and whatnot
00:34:24Have made their way into the inner solar system
00:34:26And so some of these leftovers from the formation of the solar system
00:34:31Can get a little too close for comfort to Earth
00:34:35That's how we end up with near-Earth asteroids
00:34:37We'd really like to understand the distribution of these objects, their compositions, and kind of where they come from
00:34:42So that's what we're trying to find out
00:34:44How do they leak into the inner part of the solar system and get into this region near the Earth's
00:34:48orbit?
00:35:00You don't want to just know that the asteroid is there
00:35:02You want to know how large is it?
00:35:04What is it made of?
00:35:06So there are telescopes that then go out and study particular characteristics of asteroids
00:35:11To the extent they can from the ground
00:35:14So we want to find out what is the composition of the object
00:35:19How fast it's spinning, whether it's one object or two objects
00:35:22And of course we want to know, you know, the mass of the object
00:35:26And for that we need to have an accurate idea on its size
00:35:29That's where radar comes into play
00:35:35Yeah, that's cool to finally see it
00:35:41This is the biggest one in this complex
00:35:46It's 70 meters in diameter, all the other ones are 34
00:35:50This is the most powerful planetary radar on Earth
00:35:58So here we are at the Goldstone Solar System Radar
00:36:01In the middle of the Mojave Desert
00:36:03About a few hours' drive from Pasadena
00:36:07At the Jet Propulsion Lab
00:36:08This is where I connect remotely to observe near-Earth asteroids
00:36:13I'm Shantanu Naidu
00:36:15I'm an asteroid radar researcher here at NASA's Jet Propulsion Laboratory
00:36:23That's amazing
00:36:25Whenever an asteroid comes close to Earth
00:36:28We use this radar to observe it
00:36:30Which can tell us about the shape of the asteroid
00:36:33It can show details on the surface of the asteroid
00:36:36Such as ridges, concavities, craters
00:36:38We can also measure the precise distance to the asteroid
00:36:42And then from all of that
00:36:43You get really fantastic science
00:36:46And then you get that information you might need
00:36:48In the event an impact threat is discovered
00:36:52So radar is an active form of observing an asteroid
00:36:55In the sense that we generate our own electromagnetic waves
00:36:58We use really high-power transmitters
00:37:01To transmit electromagnetic waves in the direction of the asteroid
00:37:04The asteroid reflects these waves
00:37:07They get distorted during this process
00:37:09And they come back towards Earth
00:37:12So you have signals from space coming in
00:37:15Reflecting of the primary dish
00:37:18Reflecting onto the secondary dish
00:37:20And then they reflect onto the instruments
00:37:22We can compare the distorted received waveform
00:37:26With what we sent
00:37:28And using this comparison
00:37:29We are able to generate highly detailed images
00:37:33Or maps of the asteroid
00:37:37So one example I can show you is
00:37:402024 MK
00:37:41Which was a recent target that we observed
00:37:44We were able to obtain these very high-resolution images
00:37:47Where each pixel is under two meters in resolution
00:37:50If I zoom in here
00:37:52You can see all these intricate details
00:37:55On the surface of the asteroid
00:37:57Like you can see these radar dark regions
00:38:00You can see it's a very irregular shape
00:38:03There's a lot of things that look like ridges
00:38:06So we can track these features
00:38:09And we can measure the spin rate of this asteroid
00:38:22So there's a control room in the pedestal
00:38:25This is where the telescope operators sit
00:38:28We send them the orbits of the asteroid
00:38:31We send them the observing plan
00:38:33We send them the configurations
00:38:34We want to observe the asteroids with
00:38:36So this is where the telescope operators sit
00:38:39And this is where they control all the equipment from
00:38:42And that's where the data gets collected
00:38:44And the computer behind
00:38:46And that's what we connect to
00:38:48To download the processed images at JPL
00:38:56This seems like a nice setup
00:38:57So I'll send it to the telescope operators
00:39:02When we start observing an asteroid
00:39:04We need a very accurate orbit
00:39:06So we can point accurately at the target
00:39:09We get a spectra, update the orbit
00:39:12We get a course resolution image
00:39:14We update the orbit again
00:39:16And so we transmit for a fixed amount of time
00:39:21Which is the round trip light time to the asteroid
00:39:23And as soon as that time elapses
00:39:26That is when we start receiving the echo
00:39:28We switch from the transmitter to the receiver
00:39:30It takes a few seconds to travel a few million miles
00:39:35Back into space and reflect off the asteroid
00:39:39So we transmit for an entire round trip time
00:39:42And then as soon as the echoes start reaching back to the telescope
00:39:48That's when we switch to the receiver
00:39:49And then we record the whole transmitted wave
00:39:53So for one round trip time
00:39:54And that constitutes one image
00:39:56And once we get a good orbit
00:39:59We can start getting these higher resolution images
00:40:08It's always exciting
00:40:09Because it's the first time anyone
00:40:12Is looking at the features on the surface of this asteroid
00:40:16Most of the asteroids that we observe
00:40:18We've not seen them before
00:40:20And so whatever you see with radar is a surprise
00:40:23And a lot of the times it's discovering something new
00:40:26It is very cool to know that
00:40:29At least for a few minutes
00:40:30Or maybe even a few days
00:40:31You're the only person in the world
00:40:34Who knows this thing
00:40:35It's very exciting
00:40:37It's a very exciting feeling
00:40:39There's a sense of responsibility
00:40:41Knowing that I'm part of such an important team
00:40:44And we're all tackling such an important problem
00:40:48Of asteroid threat assessment and mitigation
00:40:54Let's say we discovered something
00:40:56And we only had a small window to observe it
00:40:59And quickly turn around information about its properties
00:41:03What if we find an asteroid that's going to impact the Earth next week?
00:41:07Then all of a sudden an opportunity came up that nature gave us
00:41:11An asteroid designated 2023 DZ2 was discovered
00:41:16So this object was discovered by a team in the Canary Islands in Europe
00:41:21When it was discovered the observations were directly sent to the Minor Planet Center
00:41:25And then we published everything
00:41:26The role of the Minor Planet Center is to distinguish what is known and what is not known
00:41:32We define them as a complete new object
00:41:35And so in the following couple of hours
00:41:37A lot of observers from all over the world started observing it
00:41:40And then it was like a really large impact probability
00:41:42Which means it could impact the Earth
00:41:44Over a period of a few days it had a high impact potential
00:41:49Three years from the discovery date
00:41:51And originally it had a decently high probability of hitting Earth
00:41:55At its first discovery
00:41:58And then it was followed up and the probability went up
00:42:01And then the simple probability stayed high
00:42:04Even if people were sending more and more observations
00:42:06Which means that the path on which the asteroid was
00:42:09Was really towards the Earth
00:42:102023 DZ2 was a significant asteroid
00:42:13That kind of close approach to the Earth of a rock that size
00:42:17Might only happen a handful of times per century
00:42:19And then eventually it turned out that it was coming really close
00:42:22But it wasn't hitting the Earth
00:42:23Other observations had been made to take 2023 DZ2 off the risk list
00:42:29So that was a good thing
00:42:30Suddenly the probability of hitting Earth goes down
00:42:33And that's because the more points you gather
00:42:35The better refined your orbit can become
00:42:38At NASA we thought this would be a good opportunity to launch an observing campaign
00:42:44In coordination with the International Asteroid Warning Network
00:42:47To try to get the worldwide community together
00:42:50To gather observations about physical properties of an asteroid
00:42:54And turn that around quickly
00:42:56So we essentially had a very short five-day campaign
00:42:59Where we had to reduce the impact risk
00:43:03By observing the object and collecting more positions along its orbit
00:43:07Understand its rotation period
00:43:09Understand its composition
00:43:11Try and observe it with radar
00:43:13To get some physical information like the size and volume
00:43:16And try and input all this information in an impact hazard model
00:43:21To see what would be the impact on the ground
00:43:23So we were able to pull all of this stuff off within a matter of five days
00:43:27We took this real-world opportunity to exercise the whole system and campaign
00:43:34That would be done if a potential impactor was found
00:43:38In case we were ever faced with a situation where we needed to do that
00:43:42To measure the properties of an asteroid during a short window
00:43:46In a coordinated fashion with the worldwide community
00:43:50So we used the Goldstone radar to observe it
00:43:53And we managed to obtain images with the resolutions of under four meters on this asteroid
00:43:58Which showed that it was an irregular body
00:44:01It was spinning extremely rapidly
00:44:05Based on the visible extents in the radar images
00:44:09We could tell that the asteroid was somewhere about 30 to 40 meters
00:44:13So a bit smaller than what we could estimate using just the visible
00:44:18So it was an important target to practice working together
00:44:23To exercise the systems in order to refine the orbit
00:44:26And improve the characterization of the asteroid
00:44:31So my students and I, we observed this object using telescopes
00:44:35One on campus, we also used the NASA Infrared Telescope Facility
00:44:39Which is on Mauna Kea, Hawaii
00:44:40It is one of the few telescopes in the world that is capable of telling what asteroids are made of
00:44:46So we try and do geology with the telescope
00:44:48We're trying to do prospecting
00:44:50You know, trying to understand what minerals are there on these asteroids
00:44:53And using those mineral signatures
00:44:55Kind of these spectral fingerprints
00:44:57To identify what fingerprint matches with those meteorites that we have in the lab
00:45:03So that's what we were trying to do with DZ2
00:45:05So this is the 2023 DZ2
00:45:08This is the motion, this is the object that's moving there is DZ2, correct?
00:45:14Yeah, so you can see it moving through the star field
00:45:15Star field, and that's the spectrum, the visible spectrum right next to it
00:45:19The first order visible spectrum
00:45:21Yeah
00:45:22So in the end, what we assessed about DZ2 was that it was much brighter than we expected
00:45:27Because when an asteroid is discovered, we don't know how bright or dark it is
00:45:31So that sets a range in size, okay?
00:45:34You can slowly narrow down the size depending on more characterization information
00:45:38So if you have radar, that gives you a very accurate, you know, diameter
00:45:43You know, pretty close to the final thing
00:45:45If you have thermal infrared measurements, you can constrain the observation
00:45:48So you can constrain the diameter for that
00:45:50But you also have composition
00:45:52Composition tells you something about how bright the object is
00:45:55So that gives you an additional piece of information
00:45:57So no one technique gives you the ultimate answer
00:46:00But complementary sets of information from different telescopes, different techniques
00:46:05Kind of let us converge to one answer
00:46:08In the case of DZ2, what we've done is with the IRTF
00:46:11We spectrally characterized, we looked at the light reflected of DZ2 in different wavelengths
00:46:17And in the infrared, in the wavelengths we cannot see but rattlesnakes can see
00:46:22You know, kind of like heat-seeking stuff
00:46:24What we see is a unique spectral signature for a specific mineral
00:46:28That is only found in this particular type of meteorite called auberites
00:46:32And we have a few of those in our collection
00:46:34You know, both that fell on the Earth, fell in Antarctica
00:46:37Here's an example of it
00:46:39This is an auberite
00:46:40It's essentially white, okay?
00:46:42It's reflecting 60 to 70% of the light
00:46:44What we do is that take this meteorite, crush them into a powder
00:46:48And put them in a lab spectrometer to get the spectrum of this meteorite
00:46:53In other words, how is light interacting with it at different wavelengths?
00:46:58So, what we do here is that we take a sample and then we crush it
00:47:01And we have it, you know, being observed by the spectrometer that we have it here
00:47:06Instead of the sun, we have a light source that is reflecting, you know, off the sample
00:47:11And we're collecting visible infrared spectra off that sample that we have
00:47:15Spectrum is nothing but light split into many wavelengths
00:47:19And using that spectrum, we compare the same thing we get from the NASA Infrared Telescope
00:47:24And we can try and match, you know, the spectrum of the meteorite in the lab
00:47:29Versus the telescopic spectrum, you know, off the near-Earth object itself
00:47:33And by taking this spectrum and comparing it to the one that's coming off the telescope
00:47:38Off the near-Earth asteroid, we should be able to compare and tell what the near-Earth asteroid is made
00:47:42of
00:47:42Because it was so bright, you don't need the object to be that big
00:47:46So, it ended up being smaller than what we expected of the size range
00:47:49And because if it's smaller, you know, hopefully we pray that the atmosphere takes care of it
00:47:54And we won't have much impact on the ground
00:47:56So, that's what ended up happening is that we managed to nail the composition of the object very well
00:48:01Using the NASA Infrared Telescope Facility
00:48:04So, 2023 DZ-2 was a really interesting example of planetary defense working on an international scale
00:48:15So, it's really a resounding success in multiple organizations across the planet coming together
00:48:20And the fact that we were able to discover it, characterize it, determine it was a risk
00:48:25And then remove that risk, all before it passed close to the planet, was a pretty amazing feat
00:48:30Let's say we do find something that poses an impact threat to Earth, what next?
00:48:36The day is coming when Earth will get impacted
00:48:39The time source went extinct because they didn't have a space program
00:48:42We do have one
00:48:43We can
00:48:44So, why stop there?
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00:50:23asteroids trajectory. Now this is a watershed moment for planetary defense and a watershed
00:50:31moment for humanity.
00:50:55As was demonstrated with the DART mission, if an asteroid were ever discovered, that could pose an impact threat to
00:51:01Earth. And we do have the capability to deflect an asteroid in space and to change its orbit.
00:51:10You know, once we've found an object and determined that it could be an impact threat to the Earth, what
00:51:16do we do to mitigate it?
00:51:20Eventually, we have to be ready to nudge an asteroid off its course.
00:51:25NASA's recently demonstrated a particular type of mitigation technique that we call kinetic impact.
00:51:30In case there was an asteroid coming towards Earth and you're there, you can actually stop it. I mean, that's
00:51:36kind of fantastic.
00:51:37Our double asteroid redirection test, DART, was a demonstration of using the kinetic impactor technique.
00:51:44The idea is pretty simple. You basically just take a spacecraft and you run it into an asteroid and bump
00:51:49it out of the way.
00:51:50What? You think science fiction, but this is real.
00:51:53Never in my life would I have thought I would take a couple hundred million dollar spacecraft and crash it
00:51:59into an asteroid.
00:52:01Its main goal was to go to an asteroid with its moon to hit the moon and see how much
00:52:07it changed the orbit of the moon.
00:52:09The moonlit Dimorphos, which orbits the asteroid Didymos, in order to change Dimorphos' orbit and show that we can deflect
00:52:16incoming asteroids if we need to.
00:52:18DART will only be changing the period of the orbit of Dimorphos by a tiny amount and really that's all
00:52:25that's needed in the event that an asteroid is discovered well ahead of time before it might impact Earth.
00:52:32And space, just a little bit, is just enough to make an asteroid actually miss us. So behind me you
00:52:38see the spacecraft.
00:52:39It's really cool to see it coming together in real life.
00:52:42It is fantastic to see it in real life.
00:52:44To see it turn from ideas into real pieces that are going to go into space.
00:52:50The solar arrays will actually roll out to 28 feet in length.
00:52:54Once the solar arrays are deployed, it's going to be the size of a school bus.
00:52:58As the solar array opens out, it's going to swing out in this direction.
00:53:04To me, the most important thing and the most exciting thing is all the technical challenges.
00:53:10My job is primarily to make sure all the systems on the spacecraft work together.
00:53:14On top, you see the next C thruster. Over here is our star tracker. And then over here is our
00:53:20high gain antenna.
00:53:21My job is to make sure we launch. My job is to make sure we're able to receive data back.
00:53:26My job is to make sure we hit.
00:53:27There's Draco on the bottom of the spacecraft.
00:53:30As well, of course, is integration and tests.
00:53:36The asteroid's only two football fields in size.
00:53:39We're flying at over six kilometers a second.
00:53:42Thirty days out, we see one pixel on our field of view.
00:53:45You can see Didymos and Dimorphos as one point of light.
00:53:48About four hours out, our spacecraft becomes autonomous.
00:53:51And then that's where everything gets really exciting.
00:53:54You actually are seeing impact.
00:53:59The algorithm has to identify and hit the target in the field of view of the camera.
00:54:05And so you could just imagine if it was a human being joysticking this.
00:54:09Because we don't know for sure what the asteroids look like, our simulation gives us the capability to use different
00:54:16asteroid shapes and asteroid objects to see that our smart nav algorithm performs against all these unknowns.
00:54:24Astronomers are going to measure how much DART changed Dimorphos' orbit using ground-based telescopes all over the world.
00:54:31These curves show the brightness change due to Dimorphos moving in front of and behind Didymos.
00:54:37We can tell how quickly Dimorphos is moving around Didymos.
00:54:40We make these measurements before DART arrives.
00:54:43And then this is the same technique that we'll use after the impact to determine how much we've changed the
00:54:47orbit by.
00:54:56This is Lowell Observatory.
00:54:58Lowell is one of many observatories around the world that will be observing the DART impact, NASA's first-ever planetary
00:55:04defense test mission,
00:55:05to see how much a spacecraft impact can deflect an asteroid in its orbit.
00:55:09This is where Pluto was discovered, and we are still doing research in all areas of astronomy today.
00:55:15So let's go check it out.
00:55:21This is the Pluto Telescope, the telescope that was used to discover Pluto almost 100 years ago.
00:55:27So here we are at the Clark Telescope. This is where Percival Lowell sat to observe Mars.
00:55:33Let's head on over to the Lowell Discovery Telescope about an hour south of Flagstaff,
00:55:37which is where we are going to be collecting data for the DART mission.
00:55:40The reason we're all the way out here in the middle of this forest is that we have really dark
00:55:44skies here.
00:55:54And this is the Lowell Discovery Telescope. This is what a 4.3 meter telescope looks like.
00:55:59This is what we will be using to study Didymos and Dimorphos in the days and weeks after DART impact.
00:56:06The DART spacecraft will be hitting an asteroid called Dimorphos.
00:56:09It's special because it's a binary asteroid, which means a satellite around a larger asteroid called Didymos.
00:56:15And DART will actually be hitting Dimorphos.
00:56:17And what we will be measuring is how much DART changes the orbit of Dimorphos around Didymos.
00:56:23So this is an important test for planetary defense mitigation strategies in case we ever have to do this for
00:56:29real.
00:56:30The Lowell Discovery Telescope is one of many telescopes around the world which will be used to study Didymos and
00:56:36Dimorphos.
00:56:36It's really a global coordinated effort.
00:56:38And what we're looking at here is a large 4.3 meter primary mirror that's in the middle of the
00:56:43telescope tube here.
00:56:44Up at the top is a secondary mirror.
00:56:46The secondary mirror up top there is what is focusing the light down onto the instruments and allows us to
00:56:51take images with the camera that's located down at the bottom.
00:56:54This is maybe one of my favorite hidden rooms at the telescope.
00:56:58We're like standing inside the telescope.
00:57:01Underneath the telescope, 100 tons above your head.
00:57:03Held up by this and this, which is cool.
00:57:07This is sort of, as you can see, the highest peak around here.
00:57:10Just over 8,000 feet.
00:57:11And come up here for sunset.
00:57:13Oh, yeah.
00:57:13Because you have sun setting right there.
00:57:15It's just perfect.
00:57:17For DART, we're going to be collecting images of the night sky.
00:57:20And typically an observer would be here in front of one of these consoles controlling the instrument and taking images
00:57:24like these as they're coming in off the telescope.
00:57:27DART is really a sort of before and after experiment.
00:57:29We need to understand the system before the spacecraft intentionally impacts.
00:57:33And then we have to understand what the outcome of that impact event is.
00:57:36As we watch from the Earth, Dimorphos will pass in front of Didymos and behind Didymos.
00:57:42What we will be doing with those images is measuring the brightness of Didymos in those images and looking at
00:57:48how that brightness changes.
00:57:49And those dips in brightness allow us to measure when these eclipses happen and measure the orbit period of Dimorphos.
00:57:56And so you have essentially a fixed star field here.
00:57:58All the white dots are stars of different brightness.
00:58:01And moving through this field is Didymos and Dimorphos, which, again, we can't distinguish them as discrete points of light.
00:58:06But we have that small object moving through the field of view.
00:58:11So after impact, we will then be able to go back and start observing intensely, looking for those mutual events,
00:58:18those eclipse events of Dimorphos passing in front of and behind Didymos.
00:58:22And on each one of these frames, we're measuring the brightness to assess whether or not it's undergoing one of
00:58:28these events where Dimorphos is passing in front of or behind.
00:58:32This is such a cool experiment.
00:58:34It's such a singular experiment.
00:58:35Using the ground-based telescopes like this one and others around the world to watch the systems and see how
00:58:41it's affected by this impact event,
00:58:43because that's really what's going to give us the answer to what did DART do at the time of impact.
00:58:49And that will be exciting to see how that evolves over the days and weeks following that impact.
00:59:00Good afternoon, everybody.
00:59:03Two weeks ago, we conducted humanity's first planetary defense test.
00:59:09The team has measured that the orbital period of Dimorphos has changed.
00:59:16Astronomers have been using telescopes on Earth to measure how much that time has changed.
00:59:23These telescopes have been observing this system nightly, and that's what you see going across here on this graph on
00:59:30the top.
00:59:30Just this nightly telescopic data night after night after night.
00:59:33And it resulted in moving an asteroid and actually changing its orbit by a few millimeters per second.
00:59:40Now that doesn't sound like a lot, but acting over a long period of time, it could be enough to
00:59:45help move something out of the way of the Earth, should we ever need to do so.
00:59:48It was expected to be a huge success if it only slowed the orbit by about 10 minutes.
00:59:55But it actually slowed it by 32 minutes.
01:00:00The whole world has been watching this.
01:00:03Wow, I mean, what an exciting day for the DART team.
01:00:09In case you're keeping score, humanity, one, asteroids, zero.
01:00:14Go DART!
01:00:15The dinosaurs are made completely extinct by an asteroid impact so many years ago.
01:00:20Here we are, we can actually do something about it.
01:00:24I think this is just wonderful.
01:00:28There are times, you know, in a year or in a decade when you're in awe of humanity.
01:00:33You know what I mean?
01:00:34Despite everything that happens in the world on a day-to-day basis in a new cycle,
01:00:38there are times when, you know, human beings kind of come together to do great things.
01:00:41And I think for me personally, DART was one of those moments where you're just in absolute awe of humanity.
01:00:47You know, here we are taking a spacecraft and flying it, you know, hundreds of millions of, you know, kilometers
01:00:53away and hitting an object with that precision.
01:00:56And it all happens in a blink of an eye.
01:00:59You know what I mean?
01:01:00It was not a long mission, you know, and I think I'm very, very proud of my colleagues who managed
01:01:05to pull that off.
01:01:06It demonstrates how far we've come as a species in the last few centuries even.
01:01:11From the first rockets launched into outer space, the first asteroids being discovered,
01:01:16to the ability to realize what threat asteroids pose to the planet.
01:01:21And now the capability demonstrated to send a spacecraft to an asteroid that's in orbit around the sun
01:01:29and show that we have the capability, if we have enough lead time, to alter its orbit.
01:01:35That to me was just a fascinating moment in human history.
01:01:38Oh yeah, I did watch it. I was like, it was super cool. I did watch the DART mission.
01:01:45Yes, I have watched the DART impact. It was pretty amazing.
01:01:49The last video that they were showing live and then you saw everything up until to the last moment.
01:01:54I thought that that was such a big achievement. It's something like people work on it for so long.
01:02:00And it proved that we can do it.
01:02:03The DART impact day was one of the most exciting days in my career.
01:02:08We watched the impact here at JPL. The impact was bigger than I had expected.
01:02:14But I was also excited because we had an observing run for observing Didymos just about 11 hours after impact.
01:02:24And it would be the first opportunity to see how much of an effect the impact had.
01:02:30Didymos was all I was thinking about the whole day.
01:02:34I couldn't sleep. The observing run started at about 3 a.m. that night.
01:02:39And we had our first echo of Didymos after impact.
01:02:43We weren't expecting to measure the deflection that night, but the echo was off from where it should have been
01:02:51if there was no DART impact.
01:02:53And I couldn't believe my eyes. I was like, either there's some problems in the measurement or this is a
01:03:01real detection just 12 hours after impact.
01:03:05So this was the first Goldstone radar detection of the effect of the DART impact on the orbit of Dimorphos.
01:03:13The yellow circle, it circles the location where the echo from Dimorphos should have been had there been no DART
01:03:22impact.
01:03:22But then the red circles the echo of Dimorphos, which you can see as this white dot here.
01:03:30And you can see it's quite far away from where it should have been without the impact.
01:03:34And it just gave it a small nudge. But if you wanted to do this in the future potentially, it
01:03:40could potentially work, but you'd want to do it years in advance.
01:03:43Warning time is really key here in order to enable this sort of asteroid deflection to potentially be used in
01:03:49the future and is part of a much larger planetary defense strategy.
01:03:52The DART mission was the first kinetic impactor demonstration.
01:03:56It was a successful demonstration of that technique. There are also other possible techniques.
01:04:04If you do find one that is coming, definitely, there are several options.
01:04:08There are different types of mitigation and they actually depend on when you discover that the object is going to
01:04:13impact.
01:04:14Well, one of the most important things we can do to ensure that mitigation actually works is we need to
01:04:19provide time.
01:04:20Time is your best friend.
01:04:21I have time to build a spacecraft, go to space, analyze the object, try to understand what type of physical
01:04:27properties this object has.
01:04:29Then what we call the reconnaissance mission, to fly by or rendezvous so that we have a better understanding of
01:04:34what the asteroid is, such as the size, the mass.
01:04:38Chemical composition, for example, it is a solid rock as it has boulders, something like that.
01:04:44And then you want to know its orbit in a very accurate way because you want to track it down
01:04:48and like go straight on it.
01:04:50The next step is to figure out a mission that could potentially deflect the asteroid.
01:04:55There are other techniques, though, that still remain to be tested for asteroid deflection.
01:05:02A gravity tractor, for instance, where you just have a spacecraft of some significant mass.
01:05:11A station keep with the asteroid in the right position and the mutual attraction between the two objects will allow
01:05:18the spacecraft to slowly tug the asteroid off of the impacting trajectory.
01:05:23Another technique might be an ion beam deflector, where you've got a spacecraft that turns its ion engines onto the
01:05:32surface of the asteroid.
01:05:34Continuously bombarding the surface of the asteroid does create a pressure on its surface and therefore a force that changes
01:05:45the velocity of the asteroid.
01:05:47Of course, all the Hollywood movies like to use nuclear explosives.
01:05:53It's very dramatic and exciting.
01:05:55But we wouldn't blow the asteroid up like they do in the movies.
01:05:59You detonate the device, bombards the surface of the asteroid with heavy radiation.
01:06:08That causes the surface material to vaporize and jet off and creates an instantaneous rocket engine, so to speak, and
01:06:19shoves the asteroid.
01:06:20Really, the goal at NASA is to find the asteroids years or decades in advance that could pose an impact
01:06:28threat to Earth.
01:06:28And then you have the gift of time to address possibly not having that impact happen at all.
01:06:37NASA is just one piece in the puzzle.
01:06:39NASA has its role as the information gatherer from space and conveying that information to other agencies.
01:06:46Every piece of the puzzle must rise up to the occasion and perform seamlessly.
01:06:52To do that, we have to practice.
01:06:54NASA also participates in interagency exercises with many others across the U.S. government to step through a situation where
01:07:04an asteroid is discovered so many years ahead of time.
01:07:08Here is the type of information that is known about it.
01:07:11Here are the possibilities of what could happen next.
01:07:23Good morning, everybody. Thank you for coming. It's been a pleasure. This is our fifth exercise.
01:07:29Welcome to the fifth interagency planetary defense tabletop exercise.
01:07:32This exercise is incredibly important to bring together the world experts and decision makers.
01:07:37ESA planetary defense.
01:07:39National Space Council.
01:07:40FEMA.
01:07:41NASA headquarters.
01:07:42U.S. Space Command.
01:07:43The Department of State.
01:07:44To better prepare us for what is an inevitable future asteroid impact, we know it will happen.
01:07:51We just don't know when it will happen.
01:07:53You know, really this exercise focuses on how we plan and coordinate our activities in response to a potential impact,
01:08:01for it all to come together into a plan on how we save the world.
01:08:07And with that, I invite you all to open the blue envelope in your folder.
01:08:13And what you have in front of you is a notification from the International Asteroid Warning Network about this hypothetical
01:08:19scenario of a potential asteroid impact for the near-Earth asteroid 2023 TTX.
01:08:25At this point in the scenario, the impact probability of the asteroid is 72%, as calculated by NASA JPLC-NEOS
01:08:34and by the ESA-INEO Coordination Center.
01:08:37The impact date would be the 12th of July, 2038.
01:08:42The potential impact locations would span a corridor from the South Pacific across North America, the Atlantic, the Iberian Peninsula,
01:08:50the Mediterranean coast of Africa, Egypt to the coast of Saudi Arabia.
01:08:55Now, the size of the object based on observations from the ground, it's highly uncertain based on the brightness and
01:09:01the unknown surface reflectivity,
01:09:03the coloring of the asteroid.
01:09:05And so it's most likely estimated to be in the range of 100 to 320 meters based on what is
01:09:12known about asteroids,
01:09:13but potentially at the extreme range of 60 to 800 meters in diameter.
01:09:19All right. So the next critical factor to consider is, of course, how many people could be affected by these
01:09:24different damage sizes along the different impact locations.
01:09:27It's certainly regional to country scale based on that size range.
01:09:32For asteroids in this general size range, the primary hazard is going to be local blast and thermal ground damage.
01:09:39And the larger sizes could also cause tsunami.
01:09:43So overall, the average population risk is around 270,000 people among all the potential Earth impacting cases.
01:09:50And then, of course, there's still that 28 percent chance that the asteroid could swing by Earth and miss us
01:09:56entirely.
01:09:56We have filled out the uncertainty in 2038 with a bunch of white dots.
01:10:02And we really don't know which of those white dots is the real asteroid.
01:10:06And so we just simulate virtual asteroids and we just run them all towards the Earth.
01:10:11The current situation is that we don't know where it will hit.
01:10:14We just know that it will hit along this line.
01:10:16For this exercise over the next two days, we're going to stay frozen in time right here, right now, 14
01:10:22years ahead of the asteroid impact and figure out what do we do with the information that we have now.
01:10:27Disaster preparedness planning, international space response, information sharing and public messaging.
01:10:33So the challenge now is to figure out how do we respond and prepare for an uncertain event like this
01:10:40where we're not sure what could happen, but the potential consequences could be quite catastrophic.
01:10:46This gets at sort of what we were hinting at there, starting to talk about not just what the threat
01:10:50is, but what we could potentially do about it.
01:10:52The good news is this asteroid impact may be preventable.
01:10:55We have at least three technologies that we can consider for this, and they have different physical effects.
01:11:02So the first is kinetic impact, which is like the DART mission where a spacecraft impacts the asteroid to change
01:11:09its speed very slightly.
01:11:11The second is an ion beam where you use a controlled electric thruster to slowly push or pull on the
01:11:18asteroid and change its speed.
01:11:20And then finally, it's a nuclear explosive device where you literally boil off part of the asteroid in order to
01:11:25change its speed.
01:11:26And we also need to know the physical properties of the asteroid because all of these methods, whether or not
01:11:32they work and the specifics of how you would design them, are tailored to the specific asteroid properties.
01:11:41Through forums like this one today and tomorrow and bringing together all of you, the world experts, we can tackle
01:11:48the detection and characterization of asteroids, ways to improve coordination among allied nations.
01:11:55That's why we want to exercise all of these capabilities now and not wait until then.
01:11:59We took this opportunity to exercise the whole system and campaign that would be done if a potential impactor was
01:12:07found.
01:12:25Planetary defense is a team sport.
01:12:27Astroid impacts are a shared risk, and so we really need to work as a team.
01:12:32It's really important that we have a global effort to try to understand the problem.
01:12:35No one nation can independently save the world in case of an impending impact.
01:12:40It's a fantastic community.
01:12:42I am part of a global team of planetary defenders.
01:12:46Very proud to be part of the Planetary Defense family.
01:12:49It not only protects Earth today, but provides protection for the future.
01:13:33Just, if you have to peace in the region of this country like this, it would've been for five years
01:13:35to eight years to be the only south of the planet.
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