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Comet To Make Close Call With Mars

samzenpus posted about 2 months ago | from the skin-of-your-teeth dept.

Mars 44

sciencehabit writes In mid-October, a comet sweeping through our inner solar system for the first time will pass near Mars—so close, in fact, that if it were buzzing Earth at the same distance it would fly by well inside our moon's orbit. While material spewing from the icy visitor probably won't trigger the colossal meteor showers on the Red Planet that some scientists predicted, dust and water vapor may still slam into Mars, briefly heating up its atmosphere and threatening orbiting spacecraft. However it affects the planet, the comet should give scientists their closest view yet of a near-pristine visitor from the outer edges of our solar system.

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First pass (2)

Thanshin (1188877) | about 2 months ago | (#47529601)

I don't understand the concept of first pass. Do they really mean "first pass ever" which I suppose would also mean humanity will never ever interact with this comet ever?

Or is it "first pass since we are able to see them, but it's part of the Solar System and it will eventually come back.

Re:First pass (4, Insightful)

tonique (1176513) | about 2 months ago | (#47529615)

The theory is that there's a big (really big) store of comets in Oort's cloud on the far outskirts of the solar system. They have never been near to the Sun having been formed far from the centre. Once their movements are perturbed they may go towards the Sun.

It really may be the first pass ever.

Re:First pass (4, Informative)

Sockatume (732728) | about 2 months ago | (#47529939)

Can I take a moment to talk about how mind-crushingly vast the Oort cloud is? It doesn't begin until something on the order of 100 times the orbit of the furthest known dwarf planets, and then it goes out about a quarter of the way to the nearest neighbouring star. It's so far away that, being composed of inert space junk, we have no direct observational evidence of its existence. I mean, space is big, big to the point where thinking hard about Jupiter makes my temples ache, but the Oort cloud is something else entirely. And that's just an object on a planetary system scale!

Re:First pass (3, Insightful)

CreatureComfort (741652) | about 2 months ago | (#47530279)

"Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space."

\ RIP DNA - We miss you.

Re:First pass (0)

Anonymous Coward | about 2 months ago | (#47532769)

The theory is that there's a big (really big) store of comets in Oort's cloud on the far outskirts of the solar system. They have never been near to the Sun having been formed far from the centre. Once their movements are perturbed they may go towards the Sun.

It really may be the first pass ever.

While very insightful, I couldn't help but chuckle, as your description sounds like the comets are actually an intergalactic attack wave of alien craft, just waiting on the edge of space for someone to piss them off...

...but let's not get ahead of ourselves. We may run out of tin foil for hats.

Re:First pass (5, Funny)

jovius (974690) | about 2 months ago | (#47529623)

I hope it does the second pass for better quality at least.

encoding (1)

electrosoccertux (874415) | about 2 months ago | (#47533327)

I'm surprised how many got this reference

Re:First pass (1)

steelfood (895457) | about 2 months ago | (#47535287)

It'll be much more real after the second pass. Why, you might feel as if you were there!

Re:First pass (2)

somegeekynick (1011759) | about 2 months ago | (#47529643)

I don't understand the concept of first pass. Do they really mean "first pass ever" which I suppose would also mean humanity will never ever interact with this comet ever?

[emphasis mine] Why? (Assuming humanity lives in harmony on Earth for another few million years) It's non-periodic (the 'C' in C/2013 A1 (Siding Spring)) comet, so as far as we know, it will be the first and only pass through the inner Solar System.

Re:First pass (2, Funny)

Anonymous Coward | about 2 months ago | (#47529719)

They have meant 'first post' you insensitive clod, but they needed to bypass the lameness filter.

Re: First pass (1)

ppz003 (797487) | about 2 months ago | (#47529819)

So will Curiously be in a position to take pictures?

Re: First pass (1)

pahles (701275) | about 2 months ago | (#47530605)

That's Curiosity...

Too bad this didn't happen in 50 years (4, Interesting)

wisebabo (638845) | about 2 months ago | (#47529631)

If this happened (optimistically) 50 years from now, we'd be able to deflect the comet to HIT mars, thus delivering a lot of water and warming things up a bit. (Only, I'm afraid, a little bit of terraforming, it would probably take thousands of such comet strikes to make the planet "habitable"). Or we could make it hit one of the moons and, if done very carefully, could deliver said water to possible Mars Moon colonists (but they'd have to find a way to keep the resulting fragments from ruining near-Mars space for space travels).

More realistically, I wonder if NASA (and the ESA) have plans to move their spacecraft for best viewing. If they're worried about damage, they could have them be on the other side of the planet when it makes its closest approach. If there are any spacecraft that are on their "last legs" (low propellent, malfunctioning equipment, no more spare reaction wheels), perhaps they could even make a very risky close approach!

I expect there will be some great images! (If the HiRes camera on the Mars Reconnaissance Orbiter can take 1m resolutions of Mars from orbit, it surely will be able to take great pictures of a comet only a few tens of thousands of kilometers away).

Re:Too bad this didn't happen in 50 years (0)

Anonymous Coward | about 2 months ago | (#47529689)

Yeah, you don't want to just slam comets into the surface. That would alter the planet's trajectory if done on the scale you're suggesting. Also, I had read somewhere that it was a dozen, not thousands of impacts that would be necessary. But, I forget where I read that bit of pseudo-science. Not that it matters because it's conjecture. Dr. Michio Kaku suggested just skimming the atmosphere with the comets to heat it up over time, not a direct impact.

It's also possible that some ancient Martians, faced with the imminent extinction of their planet, did this to our planet. And, then moved here! Just kidding. :-) Fun to think about, though.

Re:Too bad this didn't happen in 50 years (2)

Immerman (2627577) | about 2 months ago | (#47531129)

So what? You're not going to alter the planet's trajectory enough to be an issue just by throwing a few pebbles at it. Especially if those pebbles are spread fairly evenly across multiple years so that the perturbations tend to cancel each other out. Even if it was just one ginormous impact that is unlikely to necessitate anything more than altering a few decimal places in the orbital parameters to keep our planetariums accurate.

Remember - both Earth and Mars have been hit by truly *massive* bodies in the distant past - in our case it knocked off enough material to form the Moon, In Mars's case it formed Olmypus Mons on the opposite side of the planet from a basin spanning a good portion of the hemisphere. And yet both planets have almost perfectly circular orbits (yeah, they've no doubt been circularizing ever since, but still).

Plus, if you don't slam the comets into the surface, how are you going to add their water to the planet? Warming the planet substantially with cometary friction heating is a fool's game - the real gains come from increasing the density of CO2 in the atmosphere so you can capture more solar energy. IIRC on Earth the CO2 from burning a single gallon of gasoline will capture something like 1,000,000x as much solar energy as was generated in the initial combustion before it gets recaptured, and without oceans or plant life I'm betting the Martian carbon cycle is *far* slower. Perhaps we could find some asteroids rich in carbon and oxygen and shatter them just before hitting the Martian atmosphere so that the whole thing burns up in the atmosphere, adding a bunch of fresh CO2 and kick-starting a little intentional global warming.

Re:Too bad this didn't happen in 50 years (1)

Thanshin (1188877) | about 2 months ago | (#47529697)

In a few years more we'll have fusion.

Fusion could make synthesizing water safer than redirecting comets.

Re:Too bad this didn't happen in 50 years (1)

gstoddart (321705) | about 2 months ago | (#47530471)

They've been saying fusion is just a "few years away" for decades now.

I'll believe it when I see it.

Fusion could make all sorts of things possible, but it doesn't mean we're near making it happen.

Re:Too bad this didn't happen in 50 years (1)

bobbied (2522392) | about 2 months ago | (#47530981)

We have fusion now... We can start a fusion reaction pretty much whenever we want. The problem is we cannot create a sustained fusion reaction that nets us industrial levels of energy and do it in a cost effective way.

What the fusion problem really becomes is a materials and technique question. How do you safely sustain a fusion reaction long enough in some kind of container so you can collect the excess energy it creates without having to replace the expensive container too often. So we have a containment question which leads to materials questions and a whole lot of complex industrial scale engineering questions.

Re:Too bad this didn't happen in 50 years (1)

gstoddart (321705) | about 2 months ago | (#47531341)

We have fusion now... We can start a fusion reaction pretty much whenever we want. The problem is we cannot create a sustained fusion reaction that nets us industrial levels of energy and do it in a cost effective way.

Then, it's pretty useless as an energy solution, isn't it?

When I say "I'll believe it when I see it", I don't mean some bench prototype which doesn't deliver, I mean a real, functioning system.

And we've been "a few years away" from having that from decades now. Until proven otherwise, I will continue to assume "real soon now" will probably not happen for quite some time.

Re:Too bad this didn't happen in 50 years (1)

bobbied (2522392) | about 2 months ago | (#47531599)

Can't argue with that... Personally, I think that funding fusion research is something we should be doing instead of messing around with tax credits for windmills and solar panels. Where I don't figure the "We are almost there!" press is true either, it *could* be if we really put some resources into this research and development and where I'm not foolish enough to think having a working fusion plant would be the end all be all of energy production, it sure would be a step in the right direction.

Re:Too bad this didn't happen in 50 years (1)

Immerman (2627577) | about 2 months ago | (#47531225)

Well, if they would stop cutting back funding to fusion research we probably would have it by now - TOKAMAK advances on that front have been keeping pace fairly consistently with initial estimates in terms of progress per dollar, but funding has been decreasing exponentially almost from the day of the initial 20-year estimate.

On the other hand the fringe projects seem to be making some pretty impressive progress on potentially far more efficient fusion strategies. EMC2's polywell fusor seems to have confirmed their theory and it's scaling properties, have worked out most of their engineering problems, and is potentially just one properly-funded full-scale prototype away from generating energy from the holy grail of p-B11 fusion. General Fusion's lead-vortex machine is still proving the components can be built to spec, but I think I heard their theory is pretty well accepted. Then there's Focus Fusion and several others. $100,000 in funding to any one of them, chicken feed compared to TOKAMAK funding, might well get us viable fusion within the decade.

Re:Too bad this didn't happen in 50 years (3, Informative)

Gothmolly (148874) | about 2 months ago | (#47529727)

Too bad the solar wind will ionize and rip away any atmosphere that accumulates due to 1000s of comet impacts. Mars has no deflector shield like Earth has.

Re:Too bad this didn't happen in 50 years (0)

Anonymous Coward | about 2 months ago | (#47529821)

That's why we need to drill into the core of Mars and install a giant Super-Resonating Magnetic Field Deflectron(tm), protected by sharks with läsers.

Re:Too bad this didn't happen in 50 years (0)

Anonymous Coward | about 2 months ago | (#47549049)

i think thats coming in the next kerbal space program patch

Re:Too bad this didn't happen in 50 years (1)

Lord Lemur (993283) | about 2 months ago | (#47530337)

Does Mars have ferrous in it's core? Wikipedia (I know, grain of salt) says Current models of the planet's interior imply a core region about 1,794 km ± 65 km (1,115 mi ± 40 mi) in radius, consisting primarily of iron and nickel with about 16–17% sulfur.

How much energy would need to be directed to Mars to melt the core, and would it naturally create a magnetic feild strong enough to protect the atmosphere?

Commets might be a bit of a blunt instrument for such an endevor, and certainly wouldn't work to keep the core liquid unless we added a lot of mass. I don't beleive there is a way we can accomplish the reheating the core, while still preserving the planet in a fashion that we could terraform. There has to be some wacky idea to do it.

Not on human timescales (1)

wisebabo (638845) | about 2 months ago | (#47530487)

While the solar wind will blow away the atmosphere in a (perhaps) short time geologically speaking, in a human timescale it would likely take thousands of years. By then, the humans could have implemented a giant electromagnetic shield (powered by sharks with frickin lasers) or have developed wormholes to directly transfer water from the water from Jupiter's moons or have migrated to the far reaches of the galaxy. Or have gone extinct.

Mars didn't become the dry desert it is today in an instant, I believe for the first half billion years or so it was a warm wet place (because of the cometary impacts during the chaotic early solar system. Hence all the evidence of flowing water). Plenty of time.

By the way, responding to other posts, it is very easy to move satellites great distances in orbit GIVEN TIME. A simple 1m/sec change in velocity would, after a month, result in change in distance of several thousand kilometers. Remember that these spacecraft are capable of quite substantial delta-vee changes (in the KILOmeters/sec). And that isn't even taking into account any kind of sophisticated planning by the mission controllers (like using gravity assists or chaotic gravitational effects "the interplanetary highway").

Re:Not on human timescales (1)

Immerman (2627577) | about 2 months ago | (#47531271)

Actually IIRC Mars may have been fairly Earthlike (at least geologically) as recently as ten million years ago, which would suggest several billion years of warm, wet history before it became the frozen desert we see today.

Re:Not on human timescales (1)

Gothmolly (148874) | about 2 months ago | (#47532527)

How are you going to create the atmosphere ON a human timescale?

Re:Too bad this didn't happen in 50 years (0)

Anonymous Coward | about 2 months ago | (#47529751)

It doesn't work like that. They can't just move the orbiters around willy nilly. They are satellites with limited ability to maneuver.

Re:Too bad this didn't happen in 50 years (1)

Anonymous Coward | about 2 months ago | (#47529781)

Its not just NASA and ESA..... ISRO will be performing a Mars orbit injection in September. Hope we get something interesting from at least one agency.

Re:Too bad this didn't happen in 50 years (0)

Anonymous Coward | about 2 months ago | (#47529897)

Almost no magnetic shielding basically negates any sort of terraforming efforts.

Re:Too bad this didn't happen in 50 years (1)

Immerman (2627577) | about 2 months ago | (#47531321)

Not necessarily - Venus has no geomagnetic shielding either, and gets hit by a far denser solar wind. In fairness it's thick ionosphere interacts with the solar wind to generate an induced magnetosphere, but such a thing could potentially be engineered elsewhere.

Plus, even without a magnetosphere we're talking about a process that takes thousands, maybe even millions of years to strip a planet of it's atmosphere - if we can build it up in the first place we should be able to compensate for the losses easily enough. Hell, Mars *still* has an atmosphere, even if it is pretty thin these days.

Re:Too bad this didn't happen in 50 years (1)

BlackPignouf (1017012) | about 2 months ago | (#47529959)

Meanwhile, we have no clue how our society could survive without oil.
We have more pressing matters than slamming comets into Mars.

Re:Too bad this didn't happen in 50 years (1)

Immerman (2627577) | about 2 months ago | (#47531463)

Sure we do - Solar, wind, nuclear, etc. are all perfectly viable energy sources, they're just currently more expensive than fossil fuels (especially when you factor in battery costs) so market forces have continued to favor those. Prices continue to fall though, and now we have Aquion selling batteries for 1/10th the amortized cost of lead-acid for stationary applications, which will ti the scale even further. And if we stopped publicly funding the various tax-breaks, subsidies, environmental damage immunities, and wars of corporate convenience that are propping up the fossil fuel industry we'd see renewables suddenly take a huge leap forward.

And if you're afraid of the sudden surge in energy prices, take all those public funds saved and distribute them to consumers instead so that they can afford the increased prices. Make oil compete on a level playing field and it really isn't all that attractive anymore as an energy source. Meanwhile as a lubricant we already have far superior synthetics, and we could live without plastic.

Re:Too bad this didn't happen in 50 years (1)

Squidlips (1206004) | about 2 months ago | (#47530317)

The orbiters do not have the fuel to move out of the way and besides it will be a big cloud of dust and vapor and ice; impossible to avoid. They best that can be done is orient the spacecraft in some way to minimize the potential damage. As far as images, well maybe. The orbiters are designed to look down, not up so some fancy maneuvering will be needed but I think it can be done. The photos will show a fuzzy blob, but more interesting will the readings from the spectrometers and other instruments. MSL (Curiosity) will be able to take pix from the surface depending on the orientation and timing; it has taken astronomical photos before.

Re:Too bad this didn't happen in 50 years (1)

bobbied (2522392) | about 2 months ago | (#47531047)

If this happened (optimistically) 50 years from now, we'd be able to deflect the comet to HIT mars, thus delivering a lot of water and warming things up a bit. (Only, I'm afraid, a little bit of terraforming, it would probably take thousands of such comet strikes to make the planet "habitable").

The problem with doing this to Mars is that it has a very small magnetic field to protect it and radiation pretty much streams in to the surface unfiltered. Where it would help to add water and gases to the atmosphere, without a magnetic field to protect it, these would eventually be stripped away by the solar wind and you'd be back to square one.

Then there is the technical problems involved in figuring out how you can get enough of a push on some unknown constantly changing mass of ice and dust to make the necessary corrections to get the thing to actually impact Mars and not just do a really close flyby. Such things are very difficult, and given the really short time frames between "Oh, I see something coming" and "It's here!" would only make that worse. There's nothing like hurrying rocket science to ruin your day.

Re:Too bad this didn't happen in 50 years (1)

Hadlock (143607) | about 2 months ago | (#47533079)

NASA is mainly concerned about micro debris from the comet/coma shotgunning the solar panels/instruments at 60,000mph

Over dramataizing (1)

Anonymous Coward | about 2 months ago | (#47529773)

The moon is about 384,000km away from the earth. The earth is about 6,400 km wide. That means only 0.027% of the area inside the moon's orbit is occupied by the earth. So this "near miss" was better described as a 1 in 3600 to one odds of hitting mars.

Re:Over dramataizing (1)

way2trivial (601132) | about 2 months ago | (#47529985)

3703? or .0277777777?

Re:Over dramataizing (1)

mrego (912393) | about 2 months ago | (#47530883)

What about the odds of hitting Deimos?

Exciting! Almost as exited about this as (0)

Anonymous Coward | about 2 months ago | (#47529777)

I was when I first found out that Falco is In Concert now, and hippies are not invited.

Re:Exciting! Almost as exited about this as (1)

Nyder (754090) | about 2 months ago | (#47530793)

Rock me Amadeus.

Slingshot? (2)

inAbsurdum (1028514) | about 2 months ago | (#47530283)

Has anyone calculated what effect Mars's gravity will have on the comets trajectory? Will it gain/lose velocity relative to the sun? Will it's orbit be narrower/wider (will the close encounter send the rock tumbling out of the system again, or will it smash into the sun)? Or will the forces involved be simply too small to have the tiniest effect?

Re:Slingshot? (2)

Immerman (2627577) | about 2 months ago | (#47531681)

I think comets tend to be moving far to fast for a gravitational slingshot to have much effect. Your basic gravitational slingsot involves a near-miss head-on collision with a planet racing towards you. You whip around the planet and fly back roughly the way you came with your initial speed plus the orbital speed of the planet. Obviously you can do a less dramatic maneuver, but you only get a fraction of the speed boost.

Comets meanwhile have typically been falling towards the sun from a good portion of a light year away, and are moving far, *far* faster than the planets, so even an ideal slingshot maneuver wouldn't alter their speed much, relatively speaking. At most their path gets deflected so that they leave the inner system with a very different trajectory than they entered with, rather than heading back out pretty much the way they came, essentially rotating the major axis of their orbit. But their orbital energy, and hence the basic shape of their orbit, remains largely unchanged. Unless of course it hits something, but that's a matter of hitting one of a few dust motes in an Olympic stadium, and is highly unlikely for any given comet.

In the case of periodic comets (those whose highly elliptical orbits will eventually bring them back into the inner system) you can have cumulative effects, especially if it happens to have an orbital resonance with one of the planets. And over the course of several orbits it's possible for gravitational effects to "fine tune" it's path in ways that increase the odds of a collision. But I believe this comet is on a parabolic path rather than an elliptical one (considerably higher orbital energy), so unless it hits something on this pass (or evaporates) it will slingshot around the sun and then depart to interstellar space, never to be seen again.

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