Slashdot Mirror
Paintball Pellets As a Tool To Deflect Asteroids
SternisheFan sends this quote from an article at MIT's Technology Review:
"In the event that a giant asteroid is headed toward Earth, you’d better hope that it’s blindingly white. A pale asteroid would reflect sunlight — and over time, this bouncing of photons off its surface could create enough of a force to push the asteroid off its course. How might one encourage such a deflection? The answer, according to an MIT graduate student: with a volley or two of space-launched paintballs. Sung Wook Paek, a graduate student in MIT’s Department of Aeronautics and Astronautics, says if timed just right, pellets full of paint powder, launched in two rounds from a spacecraft at relatively close distance, would cover the front and back of an asteroid, more than doubling its reflectivity, or albedo. The initial force from the pellets would bump an asteroid off course; over time, the sun’s photons would deflect the asteroid even more."
That's a long shot plan right there.
I think sending Bruce Willis with a thermonuclear device and a boatload of family drama might work even better.
Futurist Traditionalism
That's true, but there's something more unnerving about losing the entire human race.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
The chance of getting killed by a car when crossing the road is orders of magnitude larger than the chance of getting killed by an asteroid.
True. However one asteroid can kill all of us, unlike one car.
The probability of an event must be combined with the magnitude of an event when assessing the risk.
with enough advance warning would simply landing a rocket on the asteroid and having it provide a constant thrust be enough to have the asteroid miss ?
at a great distance it would take very little course adjustment which could be provided by a very low thrust.
the obvious complication being if it's tumbling. even then it seems that such a scheme would still work as the rocket could align itself under guidance or using the stars and provide force at the proper time.
not sure why this is never mentioned as an option.
Absolute statements are never true
Not really. Its just white paint, seems kind of boring.
Steve Jobs just turned twice in his grave.
As soon as an asteroid wipes out the human population, those odds are gonna shift a bit.
True, the odds of anybody getting killed in a car accident will be substantially lower than they are now after an apocalyptic asteroid strike...
It would take a huge asteroid to wipe out the entire human race. We're talking once every 100 million years, or so. Before we spend any resources on detecting and deflecting asteroids, let's wait another 1000 years. On the scale of large asteroid impacts, a 1000 year delay is insignificant, but on the scale of human civilization, 1000 years is huge. If our civilization is much more advanced in 1000 years, we don't need our dated asteroid impact plans. If civilization crashes, our plans will be useless anyway.
The chance of getting killed by a car when crossing the road is orders of magnitude larger than the chance of getting killed by an asteroid.
The odds of winning big in the lottery aren't very high either, but guess what? It happens to someone on a fairly regular basis.
As for an asteroid striking the Earth... maybe not likely in the short term (where it is almost infinitely unlikely), but in the long term the likelihood becomes very high (long enough term and it becomes infinitely probable).
And maybe, just maybe, you'll win the lottery and be struck by a car while the driver is looking up at an incoming asteroid.
On noes! Someone is doing something that I don't think is worthwhile! Make them stop!
Depends on where you're walking; if you walk right in front of an asteroid, your chances of getting killed by it go up quickly.
...change the number of photons impinging on the asteroid, or increase their effect?
Hey, they can fantasize all they want, but I get to vote whether I want to have my tax money diverted to crazy projects.
In the long term, we're all dead anyway. And I don't play in the lottery either. It's just as silly as worrying about asteroids hitting me.
For the same weight, you'll transfer a lot more KE to the asteroid with a marble.
I want to delete my account but Slashdot doesn't allow it.
So I'd better hope the one that's headed for a near miss is black, so it doesn't curve and land on my house. It is senseless to worry about something with such infinitesimal odds, though. We should worry about the baggage retrieval system at Heathrow instead.
We've known that incoming (and outgoing - the Yarkovsky effect) radiation can alter an asteroid's trajectory for ages. But such a solution needs to be implemented far in advance of any pending impact. At present, we don't know the trajectory of potential impactors, like 9942 Apophis, to sufficient precision to make a deflection strategy like this useful. While it's true the odds are exceedingly small, accidentally putting an asteroid into a dangerous orbit would be disastrous. Apollo astronaut Rusty Schweickart proposed putting a tracking beacon on Apophis in order to further refine its orbit, which would allow us to use such gentle deflection strategies as the one outlined in the article. NASA turned him down. Fortunately, the Russians are currently planning a mission to Apophis; so maybe it will end up getting deflected via a generous application of paint.
Your point is valid, except that the problem with estimates like that is while they are useful for estimating the risk, they don't say much about whether an asteroid of the required size is actually on its way. In other words, we don't get a do-over if the rock shows up earlier than we thought it would. Not to mention that rocks of the necessary size could be generated by the effects of a collision with another body which then suddenly expels a rock on a collision course with Earth. In that situation, we may well not see it coming until just before the window in which we need to take action to deflect it.
Existential threats like asteroid impacts are situations that you start planning to deal with as soon as you have the knowledge to do so. There is really no reason not to, since given the extreme consequences, it doesn't seem particularly absurd to maintain those plans in a constant state of revision. We know that an asteroid of sufficient size is going to hit again. It's only a matter of time. Maybe that time is a million years from now, maybe it's a week from now. I grant that we shouldn't be building an expensive specialized asteroid defense grid or mineshaft shelter/habitats right now, but an actual plan that could be feasible in the event that we end up with an unforeseen visitor is the right thing to do. In this case, scientists realize that it is very easy to miss Earth if you poke at the asteroid just a little bit when it is far enough out. It's a reasonable plan that really should not require that much expenditure to make happen, if required.
We could all end up in a future like The Road Warrior. Looked to me like everybody in that post-apocalyptic situation died in some sort of car-related accident.
I'm getting into the paintball manufacturing business on Monday. Look for my Kickstarter project, peoples.
I agree it won't hurt for people to spend some time brainstorming about this in their spare time. But before we actually set up a budget to look into this on a more structured scale, it would probably be better to use the same budget to improve road safety, for example, or encourage people to stop smoking.
I'm not sure if I'm right, but my first thought was "surely the colour doesn't matter, since the momentum of the photons are transferred whether they are absorbed or reflected?". Perhaps someone with more knowledge of the relevant physics can answer.
In any case, it seems like a very impractical proposal. Shouldn't students be given more useful topics to make studies of?
Imagine your company logo emblazoned across the surface of an asteroid.
Not only will your company have done something great for all mankind, but mankind will be reminded of it in perpetuity.
First we paint the whole thing white and then get computer controlled pain ball guns to splatter, like an inkjet printer, your company's logo all over the asteroid.
Think of watching a Papa John's ad every time you look up in the sky and having to say a little prayer that you can actually enjoy a large nutritious Papa John's pizza instead of having been reduced to a smokin' crater . :-)
MSBPodcast.com The opinions expressed here are my own. If you don't like 'em... Think up your own stuff.
We've got more than enough already. It's ok for the herd to be thinned a bit through stupidity and/or poor choices so we can spend a bit more on reducing the chances that everybody is lost.
Sleep your way to a whiter smile...date a dentist!
Timing;
According to the article the paint would have to be applied 20 years before the asteroid approach. Add to that the time to get the craft to space, load up with paint and get out to the asteroid. That may take another 20 years. That may mean a 40 year lead time at launch to be remotely viable.
Control
Paint is not a guidance system. Sure it may be able to move the rock around but it will just be in an indefinite direction. It is just as possible to move the rock closer to earth as away. Sure it moves the rock away from earth but into a trajectory that interacts with a planet that pulls the rock back toward earth.
Other celestial bodies.
As other asteroids impact or come close to the "rock on question" they will alter the path. As the rock enters the Sol system planets will exert gravitational pull on the rock. The part or all 20 years of movement may be wiped out by interaction with another object.
To me the only viable option would be to land thrusters on the rock. Use them to stop the rotation (if any), re-position to one side of the rock and apply constant thrust to alter the course. The thrusters would have to be ion based (low fuel, long duration) and probably powered by solar satellites. A solar sail could be added for additional thrust once the rotation has stopped. The issue with icy asteroids can be dealt with by limiting the thrust of the engines so as not to break the asteroid.
If the rotation was not stopped it would require many more thrusters as they could only fire part of the time.
This "proposal" sounds like "paint and pray".
Why? You say that as if it's something bad?
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Problem is, the herd thinning would not be done by brains power but by purchasing power. Now imagine an Earth where only managers and bankers will survive. The living will envy the dead.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
first or second order accurate.
Either way I don't feel safe!
If they declare that an asteroid is "headed towards earth" without taking into account the effect of photons in the first place, i'd have to wonder a little. What if they decide that an asteroid is not headed towards earth, but it happens to be "blindingly white" and the photons change its course so it is headed towards earth.
Not really, you only get to decide which crazy project your tax money will be wasted on.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
...and sued the organization staging the project into oblivion, resulting in no money being left to save the human race. But you have to understand, he had to do it to protect the shareholder value.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
The Society Of Protection of Asteroids (SOPA) will not stand for this. Anything that stands in the way of an asteroids natural path is against nature and against God.
We're going to have to move the Earth out of the way instead... how much paint is that going to take?
I can't believe this would perform better pound for pound than high explosives
If video games influenced behavior the Pac Man generation would be eating pills and running away from their problems.
In the long term, we're all dead anyway.
Rationalizing action or inaction with the fact that everyone and everything will one day be dead always fails to convince. The fact of our mortality and the eventual end of everything we know is obvious to anyone who is alive to contemplate reality.
The more interesting course of behavior is to strive even in the face of such facts, precisely as so many of us do.
blog
When playing Paintball in space, you will be pushed backwards by the recoil too
Among the many other problems already listed is whether or not paintballs will pop at 2.7 degrees kelvin.
"With patience a ruler may be persuaded, and a soft tongue will break a bone."
The problem with lasers is that you always seem to have to divert power from your shields and warp drive.
This sig is not paradoxical or ironic.
Did anyone else read that as "Paintball Pellets As a Tool To Deflect Assholes?"
In order for paint to splatter and cover some thing it must be kept liquid which in space its ABSOLUTE ZERO. The paintballs will hit like rocks and bounce off.
It doesn't matter, because the amount of CO2 necessary to launch that many paintballs that distance would contribute so much to global warming we'd be better off taking our chances with the asteroid.
What we really need is a giant tinfoil hat to enhance the asteroid's reflectivity and a North Korean missile guidance system to ensure it can't hit anything.
Our ability to gauge these isn't perfect, but Extinction asteroids do come about every 100 million years, and the next one is either due now or late. The distribution isn't random. It's cyclic.
Help stamp out iliturcy.
To me a 27 million year periodic cataclysm is suggestive of an extra solar interaction with the galactic plane. The Solar system's orbit of the galactic center is slightly tilted off the galactic plane. With an orbital period of ~50my we pass through that plane about every 25my. The vast majority of our galaxy's mass orbits in a paper thin region on this plane, but not us. Milky way is a barred spiral, so sometimes we cross this dangerous region in a matter-rich bar like we are in now, and sometimes in a gap between which is less dense. It would seem that almost every time Sol passes through this plane in a bar, Earth experiences an extinction event. I would like to see more modelling of this.
Help stamp out iliturcy.
I think davester was implying that we should as a society tackle the threats that pose a risk to all of us rather than convince people to stop smoking or drive safer, as implied by slashping. Your scenario of herd thinning by bankers and managers is actually more like what is happening now with our energy and environmental policies. Today's need for jobs and affordable energy trumps tomorrows need for jobs, affordable energy, or a safe planet that can actually sustain us. And in the end the bankers and managers, while possibly being able to horde more for the short term, won't have the physical skills, abilities, or resources of more sustainable groups such as the Amish or subsistence farmers in 3rd world countries, so they may eventually regret the decisions and folly of their youth.
As for existential threats that could take out entire nations, I suggest we try to calculate where the asteroid will land before spending billions to deflect it. Taking "personal responsibility" is a popular concept these days, so maybe we should let the most affected nations pick up the tab to rescue them, unless there is a more long lasting benefit to helping them. For example, I might ask Germany to contribute a major share of the cost to rescue them from a potential collision. If the asteroid was going to wipe out North Korea, I might just not say anything and hope any remaining Inmin Gun allow outsiders to assist survivors. If Haiti was the target I would just move the asteroid without asking anything in return - the poor Haitians have always had it bad and always suffer through the worst earthquakes, hurricanes, and other disasters.
The chances of getting killed by an asteroid are orders of magnitude larger than the chances of anyone in the world thanking us if we did manage to deflect one.
I had an uncle who worked for the water department. I don't think anyone ever thanked him for the fact that numerous generations of people in the region have no knowledge of waterborne diseases. However he interpreted the ignorance of the public on such matters are evidence of a job well done, their ignorance was satisfaction in a strange way.
Now imagine an Earth where only managers and bankers and politicians will survive. The living will envy the dead.
Fixed that for you.
Alright, but asteroids large enough to kill everyone in a major metropolitan area come more frequently. Tunguska-sized events might be as frequent as once every 400 years. If we address this more immediate, more manageable risk with today's technology, maybe in 1000 years we will have slowly progressed far enough to address larger threats.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
>you’d better hope that it’s blindingly white. No, If it blindingly white, it will already be reflecting sunlight, so then this won't work (unless we then painted it black, and cancelled out the natural effect). You'd hope for a dull asteroid so you could change it by making it blindingly white.
I'd like to point out that in space paint pellets impacting with an object are really not going to behave as we all might assume. Perhaps a test of this system would be in order before surmising that it will cover an asteroid at all. I can just see the paint conserving momentum and being deflected away from the impact due to the lack of gravity and air. Like a really bad rendition of Deep Impact some blonde reporter getting on the TV to comment on the footage of our utter failure. Someone draw a trollface getting upset about it please.
Sadly, a Libertarian cannot force his views on another, and freedom cannot spread as does the cancer known as religion.
Paintballs, eh? The big brains who work on this think that the best thing to do is to launch an ~2-ton spacecraft with an ion engine, position it near the asteroid, and let them do their gravity tango while the spacecraft very slowly changes the orbit of the pair. If it's a nice asteroid, that orbit is one that parks it in Earth's orbit for mining operations.
As compared to painting the asteroid, if the asteroid tumbles at all (space dust, uneven heating, evaporation, etc.) the entire plan doesn't fall apart.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
first or second order accurate.
According to the article we're already too late:
"According to astronomical observations, this 27-gigaton rock may come close to Earth in 2029....From his calculations, Paek estimates that it would take up to 20 years for the cumulative effect of solar radiation pressure to successfully pull the asteroid off its Earthbound trajectory. "
2029 - 20 = 2009, so we're too late.
I still don't understand why the sun's photons are better at shoving a asteroid off-course than a rocket, but i guess if Star Trek used photon torpedoes they must be pretty good
Aliens would sure think we're strange: "Why.... WTF.... did they PAINT that asteroid?!?"
my karma will be here long after I'm gone
We know that an asteroid of sufficient size is going to hit again. It's only a matter of time. Maybe that time is a million years from now, maybe it's a week from now.
Asteroids are a lot like sharks. They're scary and exciting, they're good antagonists for movies, and so we tend to overestimate the danger they pose. Yes, a shark can tear your arm off, and if you happen to run into one while swimming, you should probably head the other way. But the reality is that far more people are killed by dogs, bees, car accidents, choking on food, drug reactions, and soforth.
In terms of natural disasters, the big killers are earthquakes, cyclones, tsunamis and floods. Wikipedia has a list: http://en.wikipedia.org/wiki/List_of_natural_disasters_by_death_toll
. Since 1900, the most deadly natural disasters have included the 1931 China floods (150,000-4 million deaths), the 1971 earthquake in China (240,00-800,000 deaths), the 1970 cyclone in Bangladesh (500,000 deaths), and the 2004 tsunami (280,000 deaths). There are no well-documented instances of meteorites causing mass casualties, but even taking an ancient Chinese report of 10,000 deaths at face value, the worst impact event in the past 1000 years wouldn't even score as the worst natural disaster in the past two years.
Or look at it in geological terms. The human species has been around for about 200,000 years. There is just a single well-documented case of an asteroid causing an extinction in the past 500 million years, the Cretaceous-Paleogene Chicxulub impact that wiped out the dinosaurs. The odds of such an event happening in the next ten thousand years or so are vanishingly remote. And other major extinctions coincide with ice ages (Eocene-Oligocene event, Ordivician-Silurian event) or volcanic eruptions (Permo-Triassic, Triassic-Jurassic, Cenomanian-Turonian events). So if we really want to worry about existential threats to the survival of the species, we should worry about ice ages and volcanoes, not asteroids.
The bigger questions are: how blindly white is it already and how massive is it. You need a very good handle on both numbers if you're trying to 1) get a tight estimate on its trajectory and 2) try to perturb it with radiation pressure. Either way, you need to visit the asteroid with a probe to get those numbers before you know if painting it white (or black) will give you enough delta v over the timescale you need.
See, I think I need to sort of show where I am coming from. I don't fear things that simply kill people. Everyone is going to die sometime. I am more concerned about things that will end civilization and/or humanity.
Asteroids may be movie friendly and rare, but they are actually easier with current technology to deal with than lots of other disasters. It may cost a billion dollars to put some paint on a rock, but if it does the job, that threat is dealt with.
As for the problems you might consider a better use of money to spend for, you may well be not considering how intractable they actually are.
If you get in a car accident, you could die. Still, even if you didn't ever end up dying in a car, you are going to die of a heart attack, or cancer, or food poisoning, or (eventually) by being hit by lightning on a clear day. Your chances of death start to become 100% as time goes on.
People are always going to find ways to kill themselves or others and they will use their intelligence to counter your best efforts. Spending to stop that is like throwing money down a bottomless pit. Still, the only nice thing about that is that most people will find that their actions will eventually fall off as civilization starts being threatened.
Eventually, they will act to stop their activities in that regard or the people will thin out enough that accidents or disease simply decrease due to a lower population density. In short, the problems you are talking about will generally self-mitigate.
With a piece of mass being hurled at us by blind physics, there is no mitigation and the threat can be existential in a way that car accidents will never be, no matter how many people are killed by them every year. That's why it is a particular threat. Car accidents might kill billions over the years, but how do you count the number of people who will never even be born because one rock ended human civilization, and possibly even the species, all at once?
If this worked other civilizations would have used it and every once in a while we'd see a painted asteroid go flying by. Right? RIGHT GUYS!?
or else!