Most killer asteroids flying towards Earth currently impossible to detect - ex-astronaut Ed Lu
Giant asteroids like the one that killed the dinosaurs don’t cross Earth’s path very often, but smaller ones do all the time. Scientists are working on systems to deflect massive asteroids, but can they be trusted to stop Armageddon if it comes to it? And while the world’s governments can’t seem to cooperate to counter threats on Earth, are they taking the threat from space seriously enough? We ask Ed Lu, a former astronaut, physicist, and CEO of the B612 Foundation, which is dedicated to defense against asteroids.
Sophie Shevardnadze: Ed Lu, physicist, former astronaut, CEO of B612 foundation, welcome to the show, it’s really great to have you with us.
Ed Lu: Thank you very much for having me on.
SS: Ed, your foundation says there’s around half a million asteroids in planet Earth’s neighbourhood as big as the one that struck Tunguska in 1908 - which flattened two thousand square kilometers of forest upon impact… I’ve heard warnings a massive space rock is headed our way in October 2017. So how big does an asteroid have to be to flatten a city?
EL:The one that we saw in Tunguska in 1908 was only 40 metres across and it was more than enough to destroy a large city, so as you said it flattened two thousand square kilometres and it was no larger than a small building.
SS:But tell me something, what is more deadly about a meteor hitting Earth - its initial impact force or it triggering tsunamis or earthquakes?
EL: Well the danger from an asteroid all depends upon the size and obviously where it hits. So the bigger ones can cause more damage, the smaller ones, such as we saw in Chelyabinsk just a few years ago, it exploded in the air and it was the shock wave that did the damage. So the answer to your question really depends upon the size. Big ones can cause tsunamis, big ones can cause massive destruction. Small ones - it’s more like the explosion of a nuclear weapon in character.
SS: So it can cause tsunamis and earthquakes?
EL: Yes, you can for very large asteroids, get tsunamis or earthquakes, obviously if it hits in the ocean. But you can get plenty of damage from smaller asteroids just due to the shock wave of the explosion.
SS:You know a huge asteroid flew by Earth in April. But does an asteroid even have to hit the Earth to wreak havoc? Say it hits the Moon, or just passes a couple of kilometers away?
EL: In most cases to really do a lot of damage on Earth you actually have to hit the Earth or its atmosphere. So the ones that miss us, it’s just a nice show, you can watch them go by.
SS: So those that miss us can’t do us any harm, is that what you’re saying?
EL: Yes, it pretty much has to hit the Earth to do harm. The problem of course is that you have to know - if you want to do something about it - you have to know which ones are going to hit the Earth. And that’s the real issue - finding them and tracking them, and knowing which ones are going to hit, long before they hit.
SS: We’re going to get to that, but before that - your foundation - the B612 Foundation - is preparing to send a telescope to orbit the Sun to detect dangerous things coming towards Earth. But space agencies like NASA already have projects which monitor space objects, so why do you need your own private project to do this? Is NASA’s programme not enough?
EL: No, the programmes done by NASA and other telescopes around the world are fantastic, and they are presently aiming, their next goal is to find an asteroid larger than a hundred metres that could hit the Earth. Now a 100-metre asteroid would destroy a small country, it’s quite large. These surveys, these telescopes will not do as well for asteroids smaller than that. However, as we just mentioned, a 40-metre asteroid is enough to destroy a very large city. So there’s going to be a lot of asteroids, in fact a great majority of asteroids that could do damage on Earth are actually smaller than a 100 metres and would not be found by these current surveys, these planned surveys. So our goal at B612 foundation is to figure out technology to find and track these smaller asteroids right now.
SS: You know, I saw you joke about how asteroids are nature’s way of stimulating a nation’s space program - but seeing how you’re doing this on your own, seems like the threat of asteroids isn’t stimulating enough?
EL: Well, I disagree with that statement, because space agencies of the world like NASA are doing a lot. They are working to fund astronomers and telescopes to find these larger asteroids and as well as the science behind them, the science behind how you would deflect such asteroids. So, you know, I look at our work at B612 Foundation as being part of, you know, our collective space programme if you’d like, of human beings on Earth.
SS: You’ve explained before how crowded the Solar System is with asteroids - if there’s really so many of them, is it even possible to detect all incoming threats?
EL: Yes, there are a lot of asteroids. As you mentioned before there are a million or so asteroids large enough to destroy a major city out there. But space is big, so they’re spread out few and far between, so they don’t hit each other very much at all. But you are correct - that makes it a challenge to find them. Like I mentioned before, the size that could be dangerous could be as small as a building and if you put that millions of miles away from the Earth, it can be quite difficult to detect. And that’s what we are all working towards - finding and tracking them. But it’s possible.
SS: Say an asteroid is detected, we know it’s headed towards Earth, and it’s huge and will destroy the planet, if it hits. You’re saying we can stop it with spacecraft sent to bump the rock from its path so it misses our planet - is this kind of spacecraft already developed?
EL: We have to talk about the size of the asteroid first. If it’s something that’s going to be enough to say kill off everyone on Earth, then it’s going to be quite large. This is not the building-size thing, but more of a kilometre or larger size asteroid. And you can bump them with a spacecraft, to nudge them slightly, but you have to do it early - decades before they hit. And you may need to do it multiple times, so that’s one technique, it’s called a kinetic impact - you just run into the asteroid with a small spacecraft. Such technology does exist. We’ve run into a comet before using such a technique. We rammed a comet in 2005. There is even a mission currently being planned between the European space agency and NASA to test this technology on a small asteroid.
SS:How much time would space agencies need - to prepare and launch an asteroid-deterring spacecraft into orbit? Even small space missions take years of approval..
EL: Yes and if you are actually to have a good chance of deflecting an asteroid successfully you really want five to ten years at a bare minimum, you really want more than that if you can. In fact the earlier you do such a thing, the easier the deflection is. Which makes sense. The further away the thing is from hitting you, the less you need to change its trajectory to make it miss the Earth.
SS:Any way we can be sure sure it gets the job done?
EL: The way you guarantee that an asteroid deflection mission is successful is that you fly multiple spacecraft as backups. We have backup systems for aircraft, for spacecraft and things like that. And you can think of multiple missions as being backups to each other. If it’s really super critical and you’re building a spacecraft to deflect it, why not launch two or three?
SS: Most of the guests who come to this programme talk about politics. What we’re talking about - is it something world powers are taking seriously? I mean they can’t even cooperate and decide things on Earth, do you expect states to stop the threats from outer space?
EL: In some sense, threats from outer space are perhaps easier to agree upon than threats from one country to another on Earth, because it’s not an enemy, if you’d like, that is thinking, it’s a natural thing. It can be something we can all rally around and d something about. The hard part is deciding which ones are worthy of being deflected, which ones need to be deflected. That’s going to be the hard part - in deciding. But I think that if we knew for sure that a large asteroid was going to hit the Earth we’d come together and do something about it.
SS: I want to ask you about the trajectory - can scientists really discover the asteroid’s exact trajectory? Can’t something change at the last minute - like if an asteroid hits another object in space…?
EL:Asteroid trajectories can be measured very precisely. Now you need to measure an asteroid’s trajectory extremely precisely if you wanna know if it’s going to hit the Earth 10-20-30-50 years from now. But it is possible. And changes in their trajectories are incredibly rare, but there are things which can be predicted. So for example when NASA or the European Space Agency or Roscosmos sends a probe to Mars, or Jupiter, or Venus, that shows that you can years ahead of time predict the motion of planetary bodies. And we can do that.
SS: Now as we mentioned a couple of years ago a meteor meteor hit the Russian city of Chelyabinsk - and it came as a surprise. Another asteroid has recently passed by Earth closer than weather satellites and it was only detected hours before it flew by. Why are some asteroids passing near Earth undetected?
EL: The reason is that we have yet to discover the great majority of asteroids. If we take, for instance, the size large enough to destroy a city, say 40 metres or so, of the million or so asteroids out there we have discovered perhaps a percent or so, 10 thousand of those, perhaps. So in other words that means that 99 percent of those are undiscovered. So you should expect that the great majority of asteroids that come very close to the Earth to come as a surprise. As of right now. Which explains why we at B612 foundation are working on trying to detect them.
SS: So with today’s capabilities, how far in advance can an asteroid be detected?
EL: We believe that with the technology that we’re working on it will be possible to detect these smaller asteroids, again, with decades of warning and to measure the trajectories accurately enough that you would know which one of these, if any, are dangerous.
SS:Apart from being capable of destroying our planet, asteroids could also be useful - some of them are rich in natural resources and precious minerals. There’s already companies out there who have space-mining plans - how long before we can buy asteroid gold?
EL: Oh that’s a good question. I wish I knew the answer to that. I suspect that it’ll be some time. I suspect that the first uses of asteroid resources will actually be for water, which can be turned into rock if you have hydrogen and oxygen, and it’ll be used in space, rather than shipping things like metals back to Earth.
SS:So is there enough asteroids to go around or are world powers going to find themselves in a battle for the ones richest in resources?
EL: Well there are a lot of asteroids out there in all sorts of varying orbits. I do think that there is an enormous amount of resources out there. And if you think about it, as you’ve mentioned, asteroids are both a threat and an opportunity. And what’s the first thing you do, when you have a brand new frontier that you want to take advantage of? You map it. And so the most important thing for bose use cases is to find and track these things, know where they are. And that’s again, what our principal goal is at the moment. Build a comprehensive map of the locations and trajectories of these asteroids.
SS: Another thing we hear a lot about, scientists warn of the danger of a massive solar storm to our planet, one that can cause a major power outage - how big of an impact are we talking about? Power stations, nuclear reactors, satellites, the ISS - is that all going to go haywire?
EL: No, I mean, people have been aware of this danger for quite some time, and we have had very large solar flares that have caused things like power outages and have disrupted satellite communications and so on. So it’s something that everyone’s aware of, we’re trying to build systems that would be robust to it, but that’s not to say that a very large event can’t be very disruptive.
SS: But is the impact temporary. Are we talking about a short term blackout and how big of an area can it affect?
EL: Well again all depends on the size of the solar event. So you can have temporary power outages, but those can be very disruptive. If you lose power for 12 hours, that’s a lot of people that can be affected.
SS:So if there’s a power outage and if an event powerful enough causes that outage, what are people going to feel when it hits?
EL: You don’t feel anything yourself, except for the fact that your lights go out. And that’s pretty disruptive. I mean everything’s powered by electricity…even the fuel in your gas station. Again, the kinds of damages we’re talking about can be very big, especially from an economic standpoint. So, for instance, if you lose electricity widespread for some period of time, things like water treatment plants are run by electricity, things like the gasoline pumps at the gas station are run by electricity. If you don’t get power back running soon then there’s going to be some serious serious disruptions of daily life.
SS: Scientists are constantly monitoring the Sun’s activity, so once you see the Sun acting all weird and moody, how much time do you have before all these ions reach Earth?
EL: Well these sorts of things happen all the time, there are solar storms all the time. They call it space weather because it’s akin to the same - you know, do we have weather here on Earth? Yes, we do, you know, it’s always changing. So people monitor it for that reason. So you can see what are called active regions on the sun, these are areas, sun spots with increased activity. You can see them as the sun rotates around and you know when these things are becoming active. And they can prepare things like satellites and power networks to handle it.
SS:But how can we rely on predictions about solar storms, when scientists can’t even predict earthquakes accurately?
EL: Well, earthquakes are a totally different thing. But you in general have some time, because the light from a solar flare reaches us within 8 minutes from the sun. Whereas the radiation, the particles - the part that would cause the disruption in the Earth’s magnetic field, that can take hours longer. So there is some time that you get, some warning time that you get.
SS: We are protected against solar storms by our natural magnetic field. But now it’s failing, because it is realigning. But isn’t that normal? It all happened before, and humans were fine somehow …
EL: The Earth’s magnetic field, as you say, does occasionally switch its polarity, the North becomes the South pole and back and forth and that’s the natural process that has been going on for millions of years.
SS: So, Ed, have you heard of gamma ray bursts, because people say they are one of the most dangerous things in the Universe. They can emit more energy in one burst than the sun can over its lifetime. If our planet gets in the way of something like that, life on Earth will be over. Are we completely powerless against such a thing?
EL:Gamma ray bursts, you are correct, are extraordinarily bright things, but there’s never been one anywhere near our galaxy since we have been around to observe it. So these things primarily happen at very very extraordinarily large distances from our galaxy. So they’re very very far away, in general.
SS: So there’s no threat to our planet?
EL: It’s not something I spend a lot of time worrying about. Saying something is no threat, doesn’t mean there isn’t some possibility of it. But again, this is a tiny possibility.
SS: We’re talking about the dangers only to our planet, but is there anything threatening the whole Universe? Scientists have been warning of an event like the ‘vacuum decay’ for example. Is the Universe in danger of self-destruction?
EL: That’s pretty speculative. It’s not something that anything takes that seriously, I would say.
SS: Really? So all the scientists, all those works, you think they’re just about nothing?
EL: There’s a lot of speculative things that go on in science. I think that’s a good thing. But you have to keep in mind that the probability of these things is extraordinarily low. This is very different from, say, asteroid impact, which we see happen. Just a few years ago we watched an asteroid impact. Those things happen on a fairly regular basis. That’s completely different from hypothetical things like vacuum fluctuation.
SS:Space debris, like old satellites, is cluttering the Earth’s orbit, it’s threatening spaceships like the ISS, may mess with take-off trajectories, etc. Why can’t it all be just shot down from the sky?
EL: The space debris that you’re talking about is leftover junk from all the -- pieces that have broken off from rockets or satellites, the many thousands of satellites the we, human beings, have places into orbit. And as you correctly point out, they do hit on occasion other satellites and, for instance, the ISS. But most of these pieces that we’re talking about are very small. We’re talking about things like this. Just very small pieces. So getting them out of space is something that we don’t have any good idea how we do right now. Right now the best thing we can do is to track them accurately and know when something’s going to hit you and move your spacecraft.
SS:So is everyone at the moment just dumping their stuff in space like ‘whatever, it’s space, it’s got room’? How do you make space-faring nations clean up after themselves?
EL: That was the attitude a long time ago. That’s a process that’s already happening, there are international agreements for what’s called best practices in space. If you have a satellite that’s about to go dead you don’t leave it in an orbit once it dies, where it can get hit by something. You de-orbit it on purpose or you put it into a higher orbit. So these agreements have been made over the past few years and they’re going to make a difference.
SS: NASA has said that ‘finding a new Earth is not a matter of IF but WHEN’ - several Earth-like planets are orbiting a star, NASA says they might have life on them - but they’re 40 light years away, that’s thousands of actual human years. Seeing how we won’t be able to fly there in our lifetime, why all the excitement?
EL: Well the idea there might be life elsewhere in the Universe is incredibly exciting, cause that means that we’re not unique here on Earth and I think that would be - the discovery of life somewhere else in the Universe would be among the most important discoveries ever for me by human beings. But again, we don’t know, there are as you say, planets that could support life but that’s all we know.
SS: SpaceX is saying it will send a couple of tourists to the Moon next year. The company’s space vehicles are already preparing to head to the ISS under a contract with NASA - is private space exploration finally becoming a reality?
EL: Absolutely, private companies are driving a lot of progress in space exploration and I think we’ve only seen just the beginning of it. I think the next 10 years are going to be quite exciting.
SS:As an astronaut you spent time on board the International Space Station, you’ve flown inside a Space Shuttle - is it an experience that should be available to all?
EL: I would love for more people to have that experience. The experiences I did which required years of training, is different than what it’s going to have become for it to become more widespread. So I think that process is going to happen. And the same way that modern airline travel doesn’t require you to be a pilot now. Right? You buy a ticket and you fly someplace. And that has changed life on Earth for the better.
SS: But the first space tourist Dennis Tito didn’t take his space flight too well, despite all the training he recalled feeling sick during the trip - can you make space travel comfortable? Has is become more comfortable over the years?
EL: Well I think you have to accept that certain things are not as comfortable as sitting on your couch and eating potato chips and watching TV, right? If you want to do certain things you have to accept for now a certain level of discomfort. If you want to travel overseas you may have to take an overnight flight, if you want to go visit base camp at Mount Everest - it’s cold. So I think that’s ok.
SS: Alright Ed, thank you for this interesting insight. We were talking to Ed Lu, former spacewalking astronaut now CEO of the B612 foundation dedicated to defending earth from outer space, talking about real dangers to life on the planet, as well as the ones that are more far-fetched.