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Chris Smith / NASA file
An artist's conception shows a comet streaking through Martian skies.
It sounds like an "Armageddon" sequel, set on Mars instead of Earth: A supermassive doomsday comet is heading toward the planet in 2014, and there's nothing anyone can do about it. Not even Bruce Willis.
The comet presents a good-news, bad-news situation for the Red Planet, and for us earthlings as well. NASA says Comet 2013 A1, also known as Comet Siding Spring, is almost certain to miss Mars on Oct. 19, 2014. However, there's still a chance — a less than a 1-in-600 chance — that Mars could be hit, due to the remaining uncertainty about the comet's path. That uncertainty is likely to be cleared up over the next few months, eventually resulting in an all-clear.
Even if the comet did hit, there'd be no negative effect on Earth. However, the "Marsageddon" scenario is already adding to the concern that was generated by last month's Russian meteor blast and a near-miss by a larger asteroid.
The case of Comet Siding Spring led Henry Vanderbilt, founder of the Space Access Society, to ask a scary what-if question. "If it was coming straight at us (no more or less likely than it coming straight at Mars), and given our existing space capabilities, could we do anything about it other than prepare to die?" he wrote in a posting to the Moon and Back blog. "The short answer is: Maybe."
The comet's size is the most worrisome part of the story. Based on its observed brightness, astronomers estimate that the iceball could be anywhere from 9 to 30 miles (15 to 50 kilometers) in diameter. In comparison, the asteroid that's been blamed for killing off the dinosaurs 65 million years ago is thought to have been 6 miles (10 kilometers) in diameter.
A direct hit on Mars' backside wouldn't tear the planet apart, but it would produce an explosion that Bad Astronomy's Phil Plait estimates at somewhere around a billion megatons of TNT. That would create a huge crater, blast tons of debris into space and perhaps set off a flood reminiscent of the one that washed over Marte Vallis millions of years ago.
On Earth, the impact would be a civilization-killer.
How do you stop something like that? Scientists have proposed a variety of deflection techniques for smaller objects, when the collision threat can be detected years or even decades in advance. Those techniques range from space-based gravity tractors, to paintball shooters, to laser blasters, to laser bees, to solar sails, to "Armageddon"-style nuclear bombs. Just this week, Iowa State University's Asteroid Deflection Research Center proposed a $500 million mission to test a nuclear-armed asteroid interceptor.
"It's not a laughing matter," center director Bong Wie said in a news release.
There would definitely be no one laughing if a 20-mile-wide comet were coming at us with less than two years of advance warning. In that scenario, the only realistic option would be hydrogen bombs, and lots of them. Vanderbilt estimates it would take about 250 megatons' worth of energy to divert an object like Comet Siding Spring. At 1 to 5 megatons per bomb, that would mean 50 to 250 bombs from the nuclear powers' stockpile.
"Whether we can effectively apply that energy to successfully divert the comet, we just don’t know," Vanderbilt wrote. "The problem has been studied a fair amount, and the answers vary. Nobody’s actually tested it. We would, under the circumstances, have little choice but to try."
For the time being, Comet Siding Spring is shaping up as a huge near-miss: NASA's Jet Propulsion Laboratory's latest estimate has it missing Mars by about 31,000 miles (50,000 kilometers) — and at that distance, not even the debris flying off the comet is expected to affect the Red Planet or the probes flying around it. It helps that the comet's tail will be pointing away from the planet, as explained in this blog posting by the Planetary Society's Emily Lakdawalla.
The comet would make an impressive sight if you were watching it from Mars (magnitude zero or brighter), and NASA's rovers will likely be doing just that. But it isn't expected to reach naked-eye brightness for earthly observers. Chances are that Comet Siding Spring will make its biggest impact as another reminder that we have to address the perils posed by cosmic threats sooner or later.
Considering what's happened over the past month, how many more reminders do we need?
More about cosmic threats:
- What's worse, asteroids or comets?
- Experts: Don't blame comet for culture's doom
- Cosmic Log archive on asteroids
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.
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How long would it take to plant 50 to 250 H-Bombs on an asteroid, depending on the size of the rock?
My guess is they wouldn't be planted all at once, but fired by rocket in a particular sequence, to attempt to deflect the path away from the Earth as much as possible, in addition to trying to deflect the fragments away as well.
no chance of this working. All shots to the moon or mars or anywhere else have a narrow window to get there. We may be able to get 3 or four off that would make it to target. As a species we have planed for this event. we have used the complete earth as our home and populated with billions of us. Most would die in this type of event but some will survive. It would be back to the stone age for them. As a species we are still here and that is all that counts. Now does anything else matter? Its a wild world a lot of good things turn bad.
First, it could be only 3 nukes the size of the Russian Tsar Bomba, which was dialed back from 100 Megatons to 57 megatons for the test. Each weighs 60,000 lbs.
The real problem is indeed the time to get the package to the comet. This is more mass than we have ever tried to push beyond the moon. It would have to be a high burn trajectory without gravitational assist. Forget planting or landing the nukes on the comet. With only 2 years to impact, there would be no time to waste with deceleration. The timing of the detonation will be critical.
It seems that all potential problems we humans face can be resolved with a nuclear response. The idea of steering/destroying a large "space body" with nuclear detonations is within the realm of magic. A more practical approach is to accept that sometimes you eat cake and at other times you don't. Or put another way: Life is a giant crap sandwich and everyone has to take at least one bite.
All of you folks who are on about "nukes" need to learn both some physics and some astronomy. Nuclear weapons can in principle be used to deflect some types of astronomical bodies but not all. Some simply are not strong enough to remain intact during the explosion. Well, you might think, blowing it up is fine, but it isn't--the pieces will reassemble in a different conformation (it's called "gravity" and even small bodies have it) or they'll hit us in a cluster or in sequence, none of which will be particular improvements.
As for those saying that multiple rendezvous are impossible, that depends on the design of the vehicle and the amount of time available. If we've got two weeks notice, no, we probably can't do anything at all. If we've got a decade or more than it's less of a problem--an ion-drive spacecraft has a tremendous amount of delta-v compared to chemical rockets. And for those who are going to say that ion engines are science fiction, that would be news to the Russians, who have been operating them for more than a quarter-century.
J. Clarke,
You may have noticed that I left out whether it would work or not. Destruction will certainly not work, and given the time frame deflection will not work either. It would probably take more than the 2 years just to get an engine with enough fuel to move the 180,000 pounds of payload, into orbit. Even if it could be done in a year, the comet would be only about 6 months away at the deflection point, where the angle of deflection would have to be much greater.
No, If such a comet were 2 years away and coming straight at Earth we might want to leave a record of our civilization on the moon for the next civilization to arise to find in 60 million years.
Ion engines have powered US probes as well. The Vasimir engine is the latest of these designs. They can achieve very high speeds, but initial acceleration is very slow. When time to impact is a big factor they would need an initial chemical rocket boost to get there quickly, and this has never ben tried.
The narrow launch windows are often dictated by efficiency requirements. It would be a different matter if we were attempting to do something at all costs.
@SuperNormal,
First, we are talking about a comet, not an asteroid. From what we know, comets can range from some rocks with a lot of ice to "slushy dirty snowballs." Generally asteroids are rocky with little to no ice/water. The amount of energy that it would take to alter the course of a comet would depend a great deal on the composition of the comet.
It would not require that a comet be completely destroyed or knocked off course to do a lot of good. If it were headed for Earth, breaking the comet up into many pieces could well cause a much greater proportion of the comet to burn up in the atmosphere and a larger number of pieces would completely destruct without contacting the ground.
The problem would be in getting to the comet once it was starting to near Earth. The coma or tail of the comet would be the first challenge. The most "efficient" way of reaching a comet is a "tail approach" because it requires the least energy to slow down and match velocities. If the tail is in the way (it is not necessarily straight behind like the wake of a boat) then it would expose a craft to massive micrometeorite bombardment. Generally the coma is in the plane of the eclipticic so it is a problem that has to be dealt with. Also once closer in the sun and solar win is causing the comet to stream off chunks and actual "eruptions" of material, making an approach very difficult.
The best approach would be to catch NEO's on their way out of the solar system and apply some major nudges. It would actually be a very good application for ion drives except that ion drives are not currently very scalable and have serious problems with engine materials breaking down over time.
But you have to play the odds to a certain extent. The odds of a direct hit are infinitesimal compared to the odds of a grazing strike (such as the one over Russia recently) The more atmosphere the comet/asteroid goes through, the less damage it will do. And even a grazing strike is much moderated by the Moon. Take a look at it sometime --- many of those craters would have been on Earth had it not been for the interposition of the Moon. If you look at it this way, detection and orbital determination is the highest priority issue with being able to nudge it slightly being a higher priority than trying to prevent a direct headon strike. You have to spend your finite dollars where they will do the most good. If you continue to do that consistently, you will eventually have some sort of workable plan for everything short of small-moon-sized bodies. If you spend your dollars on every hare-brained scheme that comes along, you will end up with insufficient warning time to do anything.
The "news" needs to stop sensationalizing and just report the news. This is just the latest "scary" story they are building up for circulation. People have plenty of things to worry about without adding this giant "maybe" that they can do nothing about.
Wouldn't work, but not for the reasons most are posting.
If you nuked an asteroid or a comet, you'd most likely turn one large one into several smaller ones which would then hit the Earth as highly radioactive debris. You wouldn't have the devastation of a large, singular impact, but you would have world wide spread of dangerous contamination.
Also, the rockets we have now to carry probes out of Earths pull aren't big enough to carry a warhead that would make a significant enough impact. We don't even have a rocket that could transport humans to the moon anymore. The last one we had, the Saturn 5, we can't build again because NASA destroyed the blueprints.
The rockets we have that could lift a big enough warhead don't actually leave the atmosphere.
It's the politicians that need to be scared into spending more money looking for Near Earth Objects.
The best way to defend against NEOs is early detection. Comets usually are very long orbit objects, and there won't be much time to react if one has our number.
The blue prints for the Saturn 5 are available on microfilm at the Marshall Space flight center.
jrae
I would hate to live your boring life. You must be some conversational
"If you nuked an asteroid or a comet, you'd most likely turn one large one into several smaller ones which would then hit the Earth as highly radioactive debris. You wouldn't have the devastation of a large, singular impact, but you would have world wide spread of dangerous contamination."
Nonsense. The fragments will not be meaningfully radioactive. (and anyoone close enough to tell, wil be killed by means having nothing to do with radioactivity)
"The last one we had, the Saturn 5, we can't build again because NASA destroyed the blueprints."
More nonsense, you're repeating a myth. All the plans still exist, their locations known. But just how fast do you think it would take to re-create a system using 60's technology, including the launch pads which were re-built for Shuttle, and being re-built again for SLS?
"Also, the rockets we have now to carry probes out of Earths pull aren't big enough to carry a warhead that would make a significant enough impact."
How large/heavy do you think warheads are? ICBMs have been able to carry several of them suborbitally against terrestrial targets (Google: 'MIRV') Mars Science Lab rode to Mars on an Atlas V, a Delta-IV heavy could throw much more mas to escape...and already exists, in production. unlike the Saturn V.
"The rockets we have that could lift a big enough warhead don't actually leave the atmosphere."
They most certainly do, and not much below orbital velocity. That's why they're referred to as 'ballistic' missiles. Anything staying in the atmosphere is a 'cruise' missile.
Again, do some actual research.
Good post Frank. My thoughts exactly. Warheads have been "minaturized" to such an extent that a "bus" carries up to ten warheads. Such "buss's" could be installed on rockets and be fired off in sequence or a much larger one which might even blast a snowball comet to smithereens. Lots of unknowns though. A nickel asteroid would be a harder nut to crack but at least humanity should have an attempt at it. Maybe a side blast could affect its trajectory enough to either miss us or just a glancing blow rather than a direct impact.
How much of a reduction in Megaton-equivalent power would the earth's atmosphere cause, if the Siding Springs-sized comet were heading for us instead of for Mars?
Unfortunately not very much. As we saw with the Russian meteor (less than 100 feet in size), small objects can explode and release almost all of their energy in the atmosphere, but for objects whose size is measured in miles it's the opposite ... the vast majority of the energy would be released in the impact cratering event.
What Eric said. When an object is miles wide and traveling at 35 miles per second, the atmosphere would have practically zero effect on slowing or mitigating the impact. Even if it did, we're talking about a BILLION megatons of energy! That's roughly 50 billion times more powerful than the bomb at Nagasaki, and 17.5 million times more powerful than the most powerful nuclear device ever exploded, the Tsar Bomba in the Soviet Union. If the atmosphere was successful in sapping 10% of it's energy (a huge amount) it would still impact with 900 million megatons, and we'd be equally screwed.
Hahaha zero. Or close enough to zero that it wouldn't matter at all. Something that size hits us and we'd be history.
Nuclear weapons and explosives are far less effective than you might think. With a nuclear blast there would be some vaporization where the fireball intercepted the comet/asteroid, but virtually all the force would be directed away from the object. It is the old firecracker sitting on a tin can issue. But put the firecracker in the tin can and it does a huge amount of damage because the blast is contained. And better yet, if the blast is both contained and focused (think RPG rocket) even more serious damage can be done. But the idea of shooting military ICBMs at an approaching comet/asteroid would only be a last ditch sort of thing.
Just as explosives are used to form a lens to concentrate blast and ignite an atomic bomb by compressing its fissile material past critical mass, it might be possible to use multiple simultaneous nuclear weapons as a lens to focus a blast of copper, zinc, nickle, or even iron into a very destructive "slug"
"If the atmosphere was successful in sapping 10% of it's energy (a huge amount) it would still impact with 900 million megatons, and we'd be equally screwed."
The beginning of the 'screwing' would come from that, alone.
Consider where that energy goes. As video of the Russian object suggests, the few seconds a seriously more massive object would spend in the atmosphere would produce enough radiant energy to cause nuclear-like thermal effects over a very large radius. prior to impact.
And that means you want to deflect it enough that doesn't even skim the atmosphere and depart without impact (an object was filmed doing exactly this above the Rocky Mountains on August 10, 1972), or things will be very bad for a long distance to either side of the ground track...
This is also why you don't just want to pulverize a large object, even if you could. The energy of a million tons of gravel doesn't go away because the 'pieces are small enough to burn up,' in doing so, you get a lot of this (and a million tons of dust, ash, and rock vapor in the atmosphere), instead.
I'm gonna drop a one pound bag of sand on your head from the third floor. Would you prefer I drop the grains one at a time or should I just drop it all at once and get it over with?
The worthiness of human civilization to survive will eventually be determined by our collective willingness to make the sacrifices necessary to create a means of protecting the planet from collisions with large objects in space. With sufficient time and will, we can prepare. But we don't even know how much time we have.
Be afraid.
People should live educated and aware, not afraid. Chicken Little hysteria leads to a lack of understanding, innuendo, profiteering. We need to marshal every fact we can and push the government to act.
Jason: I get your point.
Mine is this: Fear motivates action. If there is nothing to fear, why act? There is something to fear (total annihilation). There is an urgency. If we we are worthy of survival we will act and act now.
Did you only read the last two words of my post?
No, we can't prepare. People seem to believe that if we do discover an asteroid or comet that will impact Earth, we'll have years or months of warning. We won't. At best, we'll have weeks or days. But in all likely hood, we wouldn't know it was there until it started heating up in the atmosphere and started to glow. About 1 second before impact.
The fact of the matter is, most Near Earth Objects are found after they have gone past us. Asteroids have an albedo about the same as a lump of coal. To put it into perspective, that's like sitting in the center of the field of the Metrodome in Minneapolis, turning off all the lights, putting a desk lamp with a 40 watt bulb in one endzone, and placing a lump of coal the size of a pea somewhere in the darkened stadium, on the ground, suspended in the air, on the roof, anywhere, and then looking through a drinking straw to find it.
Astronomers have identified ~9,000 NEO's. They estimate there are more than a million left to be found, and they will be the first to admit, we probably won't find the one that kills us until it strikes.
The most rational thing we can do is use this threat to help justify development of large boosters and other space technology that would be useful for other interplanetary missions as well. Having a half dozen updated Saturn-5's on hand along with a ready production line would put us way ahead of where we are now. I'll bet it could be done relatively cheap if we avoid letting the engineers waste billions on getting that last 5% of efficiency and/or payload.
Otterman: Your reasoning and information are not valid.
By "prepare" I mean put in place a system to detect and catalog every item of significant size in the solar system, ultimately to the orbit of Neptune and possibly beyond. Also put in place in various parts of the solar system a means to react in a timely fashion and adequate manner to any potential threat.
Preparation is not impossible. It is expensive and difficult and hasn't been done, but it is possible. With enough investment, you could find that pea in the Metrodome, and you could find that rock on course for Earth. A good start would be to place Hubble-like telescopes (dozens) designed for spotting rocks in orbits all over the solar system. Also we should get busy designing, building and putting in place systems to deflect the threats.
Sure, it may already be too late, we don't know the threats that are out there. If the comet headed towards Mars was going to hit us, we'd be toast. But if we continue to do nothing, it will definitely be too late for the one that has our name on it. We just need to put forth the effort to find and deflect it before it finds us.
The problem is that everybody would rather make war, or buy houses, cars and expensive electronics that make preparations. Our resources could be put to better use.
Ironic that some of the scumbag billeyeoneairs are the ones with foresight enough to start putting the infrastructure out there. I'm sure the investment is worth it, just puzzled that it takes individuals to put it out there.
dem billeyoneairs jus shoot'ten et sum fuhd beetses thaht thah gobment, ahyep
"The most rational thing we can do is use this threat to help justify development of large boosters and other space technology that would be useful for other interplanetary missions as well. Having a half dozen updated Saturn-5's on hand along with a ready production line would put us way ahead of where we are now."
No, you do the opposite. You do as much commercial space development as you can (including orbital assembly and refueling for the things you're already doing, so that there will be launchers/spacecraft in production and otherwise available, in the event they're needed for something like this.
Otherwise, you have big launchers sitting around for indefinite periods, trying hard to find other payloads worthy of them.
In the middle of all the bickering and budget cutting; in a time where people actively try to lower science to the level of "opinion", Mother Nature says, "SO. HUMANS. HOW'S THAT SPACE PROGRAM COMING ALONG?"
Can we get the OFFICIAL WORD from NASA / JPL that there will be absolutely no downrange threat to the Earth should the C/2013 A1 (Siding Spring) comet impact Mars or one of the moons of Mars? We really need their OFFICIAL WORD on this, PLEASE! - RC
(Our international community should be able to jointly afford a standing arsenal of Deep Space Ballistic Missiles (DSBMs) to defend our Earth in the future from these cosmic threats.)
(I am concerned about a massive debris field from this type of collision possibly threatening all complex life here on Earth in a downrange way with future annihilation.) - RC
Why do you think that there will be a "massive debris field"? It's going to make a crater on Mars. Mars is a long way from Earth. There may be some debris put in orbit around Mars and a little more in orbits approximating that of Mars around the sun, but the pieces that hit Earth will mainly impact the cost of collectable meteorites.
Much Science Is Opinion and Most Scientists recognize that fact , but you Start with Opinions and Move on to Proofs. The Space Program is sadly at a black hole point in its life...It continually sucks dollars in to a vacuum and will keep doing so until they solve propulsion issues..Lets face it, Rocket technology has gone as far as it is going to. A Leap forward in propulsion tech would renew the fervor of the 60's.
You wont get the public on board without the Media and the Media is in soft sell mode on Space...Seems that Giant Leap to the next Star is further out than most of us wanted to believe...Didn't we all figure in the early 70's there would be a Holiday Inn on the Moon and maybe even Mars by the 21st century..I still want that Flying Car!! ;)
Todd, the problem with the space program is not "propulsion issues". It is the cost of getting off Earth. That will not be solved by "propulsion"--the propulsion systems we have are quite adequate to the task. It will be resolved by developing a fully reusable launch vehicle that does not require inspection by a legion of engineers after every flight. Most of the cost of any space flight today is the multimillion dollar launch vehicle that gets thrown away.
read the book..."lucifers hammer" ...same impact theme;-)
And a good, if long, read!
there is really nothing we can do that can destroy this comet if it was coming at us or alter its path - with all our vast technology available, nature will have its way - we wouldn't have much of a warning if any at all and i think i would like to be surprised anyway - instead of having 10 years to ponder my doom, just have brian williams on the nightly news anounce "lindsay lohan back in jail and the end of the world coming tomorrow"
If it was inevitable of an impact, I'd go outside, look up and watch it knock me on the knoggen, kind like that movie where an asteroid or comet hit the Atlantic Ocean and that guy went to the beach and watched the 1000 foot him tsunami get him.
If it turns out that you need to deflect something from hitting the Earth, you will need as much time on your side as you can possibly get. This means you really need to be ready to hit these things BEFORE they are even detected. So when are we (as a world) going to finally get ready to hit these things (preferably before it is too late!)? Our international community should be able to easily afford to do this thing together. - RC
We're too busy developing more and more sophisticated weaponery to kill each other with over differences in our particular flavours of cave-man superstitions.
It's much more likely civilization will be wiped out by global warming but that makes for boring news copy.
Hahahahahaha!! Global warming. Bahahahahahaha!!
Some say the world will end in fire, some say ice. But it will end. Here's rooting for ten thousand centuries down the road.
What about using just enough deflection to steer any incoming toward the moon, either for impact or at least gravitational deflection?
We kinda need the moon in one piece.
If it's big enough to break the Moon into multiple pieces then we are not going to have the slightest chance of doing anything about it. You people who think that some little bitty rock is going to shatter a planet into multiple pieces need to get a little bit of perspective. And compared to the Moon, something 30 miles in diameter is a little bitty rock.
Maybe, but if this thing hit the moon the ejecta would be raining down on us for decades. LEO would be unusable for decades. A small change in the moons orbit would equal big changes in tidal forces effecting earth.
A 300 mile wide mile deep crater would put a significant portion of the moons mass into space, and just the difference in the moons remaining mass could cause major problems. (Anybody with the math to calculate the %?)
You don't have to shatter the moon to have a mess that is catastrophic.
Learnt: I would say that even an impact as catastrophic as that on the moon would not substantially affect the orbit or mass of the moon. Not enough to matter to us anyway. However, you do make a good point about the debris field such an impact would raise. Not just Low Earth Orbit, but all useful orbits in the Earth-Moon system would be useless for at least a few years. We might get lucky and a few satellites would survive, but I wouldn't be hopeful about it. Anyway, this would probably make a good premise for a sci-fi story. What would human civilization look like if we lost the ability to use the skies?
Ernie, the object might not even be coming in from a direction where the Moon is even relevant...
Maybe we'll be lucky and cook the planet before a comet hits. We're selective which science we want to believe.
Bombing a comet into thousands of smaller comets may not solve the problem. Need to be thinking of a way to nudge these things into a different path.
The nuclear option doesn't involve hitting the comets with nukes, but detonating them close to the surface. The idea is that the explosive force will be the nudge the comet needs to miss. The heat from the blast could also cause vapor jets on the surface to push it even more. The main problem for us right now is "How do we get all those bombs to the comet in time to make a difference?"
If it does hit, that will give us a lot more understanding of the problem. The whole "releasing a flood" thing is fascinating. What would happen when mars suddenly had water?
I realize my reactions are those of a completely ignorant person who reads a lot of sci-fi.
If Mars suddenly had an ocean or even a big lake I think that there would be much greater interest in exploring the place.
Mars can't really hold a decent atmosphere, a water lake would likely sublimate before we could get there to take a drink. Without a magnetic field mars wont hold a deeper or denser atmosphere and as the lighter elements get stripped away the pressure on the surface goes down making it increasingly easier for more of the water to sublimate. If its warm enough for liquid water then evaporation from the surface and out into space would happen even faster as Mars cooled back to its ambient temp.
Terraforming Mars would start with making a giant magnetic field to protect the atmosphere.
Given our current technology, would be easier to just live underground, ala Caves of Steel. Once you're down there, it's easier to build struts and stuff because on Mars dirt weighs about 1/3rd as much. Same for the moon, actually.
yeowp! Let's just get out there doing it. Terrafarming is fore laterz when we get ta da starz. [-;
Why do humans worry about something we have absolutely no control over? There are things down here on planet Earth we need to fix right now. Maybe if we do things right here, then the universe won't throw fireballs at us whenever we go somewhere like Mars.
Maybe no control NOW, but that doesn't mean that we can't do something about it in the future. I have a feeling that someone said the same sort of things about small pox, for example. If we just take a defeatist attitude, then, yes, we will have no control over our own fates.
The universe will "throw fireballs" at Earth regardless of what we do.
Hey, Elllen! You're kinda cute! But...
I don't think the universe is "throwing fireballs" at us because we are going to Mars instead of doing things right here. The universe is just throwing fireballs randomly.
We could do something about it, but we are too preoccupied with going to Mars looking for signs of past life, buying big homes, nice cars, and electronic gadgets etc. to dedicate ourselves to protecting the planet from such threats. So, when a fireball hits, we can sit in our big homes in front of our big TVs or sit in our nice cars with our smart phones and watch it kill us, knowing that it happened the same way on Mars millions of years ago!
You are correct about this, however: We are not doing things right here. We are providing ourselves with luxuries instead of providing ourselves and our descendants with a secure future.
"Why do humans worry about something we have absolutely no control over?"
Because, unlike storms, volcanism or earthquakes, this is something we have potential control over.
"There are things down here on planet Earth we need to fix right now."
Why do you speak as if they're mutually exclusive? And one big rock can render all the other problems irrelevant.
"Maybe if we do things right here, then the universe won't throw fireballs at us whenever we go somewhere like Mars."
The Universe doesn't 'care' what we do. It's impersonal, it doesn't sit in judgement (what did the dinosaurs do wrong?), it just does what it does.
Because humans think "they're all that".
Will the 4th Season of Game of Thrones have been aired by then...just in case? That's all I'm concerned with.
Depends. What is "Game of Thrones" and where is it showing?
HBO, and the books are Way better than the series.
Sell the fear, as if the human race could ever get their petty little differences out of the way for the greater good of mankind. Pure BS
If the Russians and the Chinese failed (as the right would paralyze any meaningful American reaction until far too late) the comet would certainly bring their eternal filibuster to an abrupt end, wouldn't it? For a decent read and a graphic description of cometary impact, check out "Lucifer's Hammer".
I hate to make this discussion political, but I feel that would be a real risk. A substantial portion of the right seems rabidly anti-science, such as Marco Rubio who initially said that the age of the Earth was unknowable. And, let's remember that Todd Akin, the Congressman who claimed that women couldn't get pregnant from rape, was also on the House Science Committee in the last Congress.
"If it's a legitimate cometary impact, the planet has ways of shutting that whole thing down"
If we start hearing the Right spout that line on talk shows, I'm blaming you!
Politicians often showcase ignorance- but scientists (specialists in general, in my experience) often have a really hard time conveying complex ideas, which in fairness is the other part of the problem.
Still....I'm not really sure the right would get in the way- after all, the idea of a small, fast object wreaking havoc to a larger object isn't all that tough to assimilate...see: http://iconicphotos.wordpress.com/2009/08/19/edgerton-rapatronic/
Every picture tells a story...
A lot of untruths in this article.
First off is the estimate of 31,000 miles. Other estimates vary from that. That is just JPL labs at NASA's estimate. The Russian Labs estimate is 24,000 miles. And one Astronomer combined the two data sets and came up with ZERO minimum--and a 1 in 100 chance of hitting Mars or 1%.
Secondly, the 1 billion megaton is the minimum. Others have it at 20 billion megatons.
But to be more precise--from Wikipedia is the following:
So Shoemaker 9 was 600 times MORE powerful than the dino killer of 65 million years back here on Earth, and Comet C2013/A1 is 1800 times MORE powerful than the dino killer.
That's more than an order of magnitude greater and so estimates of the crater are up to 600 miles by 3 miles deep (some as low as 300 miles by 1.5 miles deep).
That's enough debris--about 10 times the mass of the Comet itself--that about 5% or more would be flung out into space in every direction at high speeds. And since the Sun is BETWEEN the Earth's orbit and Mars it will speed those asteroids up and sling them just about anywhere in the Solar System.
And with Billions of them some will obviously make it to Earth and most will be small--but not all. Some could be as big as 500 feet and cause substantial damage back here on Earth--we just don't know until we point our telescopes at the direction of Mars following an impact.
So trying to minimize the danger is fool hardy--as fool hardy as those at NASA who spend billions on exploring dead planets but almost NOTHING on tracking asteroids and Comets.
If we get pulverized it's our own damn fault for stupidity.
What would this much kinetic energy do to Mars' orbit? We talk about using a tiny gravity tractor to move asteroids around. Isn't this enough energy to shift the planet's orbit? Even a small change would affect our (Earth's) orbit, but the change might not be noticeable right away. All four inner planets orbit in resonance, so what affects one affects all.
Tom - I don't know diddly about astro-mechanics but that sounds at least plausible to me. I just wanted to add this shout out - I'm proud to come from a planet that has an Asteroid Deflection Research Center - yay Iowa State! I'm kidding of course, but did anyone check for bugs on any of those outer planets?
So now do you all see why I am (gravely) concerned about any downrange debris field (i.e., 'debris cloud'), if this massive comet (C/2013 A1 (Siding Spring) ever deflects (richocets) off of Mars or one of the moons of Mars ??? - RC
Wish there was more talk of sending missions to this, or any, large comet to experiment with trying to destroy it, or nudge it (obviously, not re-directing it to Earth)... hate to wait for the big one coming at Earth to then "try" to deflect it. We NEED to have some proven method(s) of avoiding our own extinction !!! There just doesn't seem to be any consensus on how we're going to save ourselves. We don't seem to have any co-ordination among space agencies, militaries or countries... are we going to wait until we see the killer-comet on our horizon ???
"What would this much kinetic energy do to Mars' orbit?"
Take a good look at orbital images of Mars. It's been smacked around more than once in the past, yet we're still here.
The solar system is not as delicate as you seem to think, or it would have disrupted itself, long ago...
Yes you're right, and both Mars and Earth have gone through extreme changes in climate during all that time. The solar systems we are finding show evidence of planets migrating around. The solar system is not as permanent as you think.
Frank Glover. It already did that when Jupiter pulled apart the planet formed between Mars and Jupiter EONS ago. Star systems routinely flick entire planets out of their solar system when larger planets like Jupiter's orbit infringe on 'stability' of systems. It's estimated that their are almost as many dead planets BETWEEN the stars than orbiting the stars!! That's from Discover HD and was on DirecTV recently. It's a fact. So your totally wrong Mr Glover.