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Easily-Captured Asteroids Identified

Soulskill posted about a year ago | from the if-they're-any-smaller-you-have-to-throw-them-back dept.

Space 160

Hugh Pickens DOT Com writes "Long overlooked as mere rocky chunks leftover from the formation of the solar system, asteroids have recently gotten a lot more scrutiny as NASA moves forward with plans to capture, tow, and place a small asteroid somewhere near our planet. Two different private space companies, Planetary Resources and Deep Space Industries, plan to seek out and mine precious metals and water from near-Earth asteroids. Now Adam Mann reports that astronomers have identified 12 candidate Easily Retrievable Objects (EROs) ranging in size from approximately 2 meters to 60 meters in diameter that already come (cosmically) close enough to our planet — close enough that it would take a relatively small push to put them into orbits at Lagrange points near Earth using existing rocket technology. For example, 2006 RH120 could be sent into orbit at L2 by changing its velocity by just 58 meters per second with a single burn on 1 February 2021. Moving one of these EROs would be a 'logical stepping stone towards more ambitious scenarios of asteroid exploration and exploitation, and possibly the easiest feasible attempt for humans to modify the Solar System environment outside of Earth (PDF),' write the authors in Celestial Mechanics and Dynamical Astronomy. None of the 12 ERO asteroids are new to astronomers; in fact, one of them became briefly famous when it was found to be temporarily orbiting the Earth until 2007. But until now nobody had realized just how easily these bodies could be captured."

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Great! (0)

Anonymous Coward | about a year ago | (#44563297)

What could possibly go wrong when tying to snag an object that is hurtling though space and will wreak havoc on anything it hits?

captcha: unproven

Re:Great! (-1)

erroneus (253617) | about a year ago | (#44563469)

It doesn't have to hit Earth to affect it. Consider the tides. Our global eco system has evolved to expect tides. It would be difficult if not impossible to predict the full extent of the harm that could result if tidal patterns are altered. All sorts of life could flourish or die under such changes.

I'm not exactly a tree-hugger, but I certainly appreciate the factors and influences over life on this planet. This would affect the oceans in all sorts of ways. That which affects the oceans and the life within them will affect us and possibly even global weather patterns.

Re:Great! (5, Insightful)

Thanshin (1188877) | about a year ago | (#44563519)

It doesn't have to hit Earth to affect it. Consider the tides. Our global eco system has evolved to expect tides. It would be difficult if not impossible to predict the full extent of the harm that could result if tidal patterns are altered. All sorts of life could flourish or die under such changes.

I'm not exactly a tree-hugger, but I certainly appreciate the factors and influences over life on this planet. This would affect the oceans in all sorts of ways. That which affects the oceans and the life within them will affect us and possibly even global weather patterns.

Because a 2~60m diameter stone in space can significantly alter tides.

Re:Great! (1)

Conspiracy_Of_Doves (236787) | about a year ago | (#44564307)

Because a 2~60m diameter stone in space can significantly alter tides.

No, but once you start getting hundreds or thousands of them in near orbit, it might start having an effect that is noticeable in some places.

Re:Great! (2, Informative)

dywolf (2673597) | about a year ago | (#44564797)

that many of them i'd expect them to be largely equally spread out, or near enough to be considered such. as such, the effect would be close to nil, and the net effect would be zero. note also that this entirely ignores the problems of keeping a few thousand (or hundred thousand!!) objects orbiting the earth at tens of thousands of miles per hour without colliding, which they surely would, quickly forming a problem many orders of magnitude in excess of the current problems with space junk.

in other words, the tidal effect is both neglible and not the primary concern in that scenario.

Re:Great! (0)

Anonymous Coward | about a year ago | (#44564885)

Because a 2~60m diameter stone in space can significantly alter tides.

No, but once you start getting hundreds or thousands of them in near orbit, it might start having an effect that is noticeable in some places.

The only effect you're likely to see is them colliding with other shit in orbit.

You're completely ignoring basic math. All you have to do is compare the mass of the moon to its tidal influence, and do the basic calculations on the (negligible) increase in gravity for the rocks (because they're closer), and you'll see that you're going to need something more on the order of hundreds of thousands, if not millions, before you start having a significant effect. And that's assuming you clump them all together in one spot. And ignoring the fact that they plan on mining the things out and distributing the mass.

The argument is pretty similar to the one which claims that propeller driven aircraft are causing hurricanes.

Re:Great! (0)

Conspiracy_Of_Doves (236787) | about a year ago | (#44565075)

I'm not saying that it's going to cause tidal waves. I was just suggesting the possibility that it might upset some ecological niches.

Of course, we're doing a pretty good job of that by other means.

Re:Great! (1)

ShieldW0lf (601553) | about a year ago | (#44565337)

C'mon dude. Drywolf said the effect is neglible. Why worry?

Re:Great! (2)

someone1234 (830754) | about a year ago | (#44565257)

We are not just collecting them, the plan is to mine them. And what's this talk about hundreds or thousands? Even if asteroid mining becomes an industry, i doubt there will be more than 10 at a time. Eventually, they will learn to mine them on spot or use the Moon for it, without towing them to Earth.

Re:Great! (1)

Anonymous Coward | about a year ago | (#44565379)

Because a 2~60m diameter stone in space can significantly alter tides.

No, but once you start getting hundreds or thousands of them in near orbit, it might start having an effect that is noticeable in some places.

Have you any grasp of how big a difference 12 orders of magnitudes is? De you think "hundreds or thousands" is ANYWHERE near 1,000,000,000,000?

The world's population is roughly 6 billion, and that is just 6,000,000,000 (3 less zeros than above). If we have 1 such asteroid for every single person on Earth, the volume of these rocks would still be only less than 1% of the Moon.

Do you also worry that America will sink under the sea if a few thousand foreigners come to visit the US?

Re:Great! (0)

Anonymous Coward | about a year ago | (#44565503)

Because a 2~60m diameter stone in space can significantly alter tides.

No, but once you start getting hundreds or thousands of them in near orbit, it might start having an effect that is noticeable in some places.

10 million asteroids would not have any noticeable gravitational effect on the Earth, even if you could coalesce them into one big one. The only potential issue would be whether their combined mass would influence a fly-by asteroid enough to make its return journey alter to be that of an impact path.

Re:Great! (5, Insightful)

Anonymous Coward | about a year ago | (#44564413)

It doesn't have to hit Earth to affect it. Consider the tides. Our global eco system has evolved to expect tides. It would be difficult if not impossible to predict the full extent of the harm that could result if tidal patterns are altered. All sorts of life could flourish or die under such changes.

I'm not exactly a tree-hugger, but I certainly appreciate the factors and influences over life on this planet. This would affect the oceans in all sorts of ways. That which affects the oceans and the life within them will affect us and possibly even global weather patterns.

Because a 2~60m diameter stone in space can significantly alter tides.

The level of numerical illiteracy* of the general public (i.e. the GP) is appalling, and combined with the boatloads of self-esteem fed to them during school years, it resulted in people worse than being totally ignorant.

A totally ignorant person would either ask the above question without assumption, e.g. "Is it possible for the captured asteroid to affect the Earth in any meaningful way?", or just assume the experts have already thought about it. Only those who knew just enough to be dangerous would both assume their imagination (considerations that is not based on hard facts nor experience is no different than imagining things) is correct, AND the experts have not considered it already.

* - by that, I mean the lack of sense in numerical scales and numbers. The radius of the Moon is in the order of ~1000km, so a 60m asteroid (round to 100m) is 4 orders of magnitude in linear dimension and thus 12 orders of magnitude in volume. How lack of numerical sense do you need to be to think that something 12 orders of magnitude smaller can have any impact?

Re:Great! (0)

Anonymous Coward | about a year ago | (#44564645)

Because a 2~60m diameter stone in space can significantly alter tides.

If the stone were made of neutronium it could. :D

Re:Great! (0)

Anonymous Coward | about a year ago | (#44564861)

Then it wouldn't be "stone", would it?

Re:Great! (5, Funny)

drinkypoo (153816) | about a year ago | (#44563525)

It doesn't have to hit Earth to affect it. Consider the tides.

Why not consider the Lily? Look, the largest of these objects is sixty meters in diameter. I'm math-challenged, but a quick back-of-the-napkin calculation reveals marinara sauce and a little olive.

Re:Great! (1)

Conspiracy_Of_Doves (236787) | about a year ago | (#44564311)

And how many of them are we going to be pulling into orbit?

Re:Great! (1)

Anonymous Coward | about a year ago | (#44564599)

If we somehow manage to move enough matter into orbit to change the tides significantly then we have already demonstrated the technology to move the moon orbit to offset the change.

Do you realize how insane that sounds? Even if we scale up the space mining industry to dwarf the mining industry on earth we will not be anywhere close to change the tides more than the moons receding from the earth already does. (Yes, the moon isn't in a perfect orbit and the tidal forces are reduced for every year. The change is way too small for you to notice.)

Re:Great! (0)

Anonymous Coward | about a year ago | (#44564929)

And how many of them are we going to be pulling into orbit?

Simple math you should have learned in high school would tell you that it wouldn't matter if we pulled in every last one we know about. I'll leave the actual proof for you to do as homework. But I'll throw you a bone to get started- it's the mass which matters, not the diameter.

Re:Great! (3, Funny)

owlstead (636356) | about a year ago | (#44564589)

I'm just glad you used the back of a napkin and not a piece of toilet paper...

Re:Great! (1)

Anonymous Coward | about a year ago | (#44563575)

An asteroid of 60 meter diameter has negligible mass. It would not have any noticeable impact on the tides be short of the size of the Moon.

Re:Great! (5, Interesting)

Kookus (653170) | about a year ago | (#44563577)

There's stuff whizzing past us all the time with the gravitational attractive force that these rocks will have. It's not going to impact tidal patterns until we start capturing relatively large objects... like relative to the moon kind of size.

You know you only have to stand about 6 feet away from somebody to have the same gravitational pull on them as Mars has on you when it's closest to earth?
Mars already impacts our tidal patterns more than these rocks.

Re:Great! (0)

Anonymous Coward | about a year ago | (#44563847)

I'm not talking about hitting Earth (though that wouldn't be a desirable scenario). If there is a small miscalculation in their approach and it hits the spacecraft attempting to lasso it ... negative result. Any you're not getting any blackboxes from that wreck.

Re:Great! No Math for us! (1)

Anonymous Coward | about a year ago | (#44563887)

Consider the tides. Our global eco system has evolved to expect tides...

I know dick about astrophysics and even I can tell that this is bullshit.

Diameter of the moon: 3,474.8 kilometers
Diameter of the largest object mentioned in the article: 60 m

By your reckoning the ISS should be wreaking havoc on the hermit crab population. Please so some simple back of the napkin math before spewing FUD

Re:Great! (0)

Anonymous Coward | about a year ago | (#44564281)

SOmeone downmod this gaffet and tell him to gtfo this site.

Looks like it's time (4, Interesting)

halltk1983 (855209) | about a year ago | (#44563303)

Looks like it's time to build a foundry in space so we can begin the construction of satellites, space stations and long range spacecraft with materials readily available in space, so we don't have to keep carting it up there. Between that and robots and assembly machines, we should be able to build out stuff in the next couple decades.

Re:Looks like it's time (2)

Thanshin (1188877) | about a year ago | (#44563479)

Or just send a micro 3Dprinter robot that can mine the asteroid and use the material to self-replicate.

Dak Tak Lak Pak.

Re:Looks like it's time (1)

morgauxo (974071) | about a year ago | (#44563713)

If you can think of a way to make a printer robot, with all it's moving pieces, electronics, etc... using nothing but rock and metal then you might have something there. I can't wait to see your motor windings made of rock insulated wire, asteroid derived lubricant, rock circuit boards, etc...

Re:Looks like it's time (0)

Anonymous Coward | about a year ago | (#44563853)

GIven enough energy and with the right technology, it is possible to make changes on sub atomic level. Electrons, protons and neutrons are there, just not at the right place.

Msg-uuid:FA97F94D-8453-4E41-8FA3-3DC1CDAA1B1C

Re:Looks like it's time (1)

FSWKU (551325) | about a year ago | (#44564283)

motor windings made of rock insulated wire, asteroid derived lubricant, rock circuit boards, etc...

Sounds like the company is run by one of Mr. Slate's [wikia.com] descendants.

Re:Looks like it's time (1)

Immerman (2627577) | about a year ago | (#44564429)

Electronics can be brought up from Earth, they're mostly small and light - at even $10k/pound delivery charge a cpu is only a few times more expensive than on Earth. A motor is a little pricier, especially a large high-power one if you needed such a thing, but still relatively cheap compared to a spacecraft. Most of the mass of any orbital structure will be (drumroll please) the structure. Girders, skin, shielding, etc. If we can print or otherwise manufacture a big reinforced steel can then the electronics, ion drives, etc to turn it into a functioning space ship or whatever are a minor cost to lift from Earth.

As for a rock+metal motor - that actually sounds like a pretty easy project with a 3D printer - but just keep printing narrow alternating tracks of wire and concrete until you've built up enough windings - it's not like you need any flexibility in the mechanism post-construction. Just bring a couple quality ring bearings up from Earth and you're good to go.

Re:Looks like it's time (1, Interesting)

drinkypoo (153816) | about a year ago | (#44563505)

What do you propose to build the foundry out of?

We need to capture one of these objects before we have the material to build the foundry!

Re:Looks like it's time (5, Insightful)

Thanshin (1188877) | about a year ago | (#44563569)

What do you propose to build the foundry out of?

We need to capture one of these objects before we have the material to build the foundry!

If only we had a large mass of material anywhere close by...

Re:Looks like it's time (4, Insightful)

halltk1983 (855209) | about a year ago | (#44563675)

I don't mind launching the materials to build the initial foundry, it's that foundry which will provide the materials for the other ones. Everyone knows that's how you play an RTS.

Re:Looks like it's time (5, Funny)

DexterIsADog (2954149) | about a year ago | (#44564445)

The problem is the jerk next door who used those initial foundry materials to train combat troops, who come over and take *our* foundry.

I suck at RTS's because I hate them. Or vice versa.

Re:Looks like it's time (1)

Chris Mattern (191822) | about a year ago | (#44564343)

Bootstrap. A minimal set of tools sent into orbit to build a bigger set of tools. Two or three iterations can have large scale foundries up and running, while building some other interesting things along the way.

Re:Looks like it's time (0)

Anonymous Coward | about a year ago | (#44565009)

Bootstrap. A minimal set of tools sent into orbit to build a bigger set of tools. Two or three iterations can have large scale foundries up and running, while building some other interesting things along the way.

This isn't a video game, you can't just drop a "tools factory" on an asteroid and feed it "rock" to produce everything you need. Most of the materials you need to build the bigger tools aren't on the asteroid so you're kind of SOL. This is the same reason why sci-fi stories about pre-landing factories and habitats on places like Mars isn't feasible.
If we had the technology to locate the raw materials, mine them, refine and process them, and then produce finished goods fully automatically we wouldn't use humans to mine anything on Earth anymore either.
Theoretically this sounds like a great idea, but the engineering is a nightmare. Speculating that it "could" be done is a world away from actually doing it.

Re:Looks like it's time (0)

Anonymous Coward | about a year ago | (#44563931)

Fuel's the only problem for unmanned space. Mass of the rest of the crap is trivial. Mining asteroids doesn't solve, or really address at all, the fuel problem.

Re:Looks like it's time (1)

camperdave (969942) | about a year ago | (#44564171)

Fuel's the only problem for unmanned space. Mass of the rest of the crap is trivial. Mining asteroids doesn't solve, or really address at all, the fuel problem.

Fuel is trivial too. The main problem is that all of it is sitting at the bottom of the planet's gravity well. Climbing out of that well requires big rockets, and big rockets are expensive to design and build. As far as fueling them, that is "in the noise" as they say: costing hundreds of thousands of dollars on a project that costs billions of dollars.

Re:Looks like it's time (1)

Type44Q (1233630) | about a year ago | (#44564449)

Mining asteroids doesn't solve, or really address at all, the fuel problem.

I seem to recall reading more than once that asteroids represent a supposedly excellent source of water (though surely H20 isn't the only viable source of reaction mass...).

Re:Looks like it's time (1)

Immerman (2627577) | about a year ago | (#44564479)

Actually lots of asteroids are apparently rich in ice and simple hydrocarbons - great raw material for synthesizing rocket fuel. The Moon's surface is similarly rich, and while you are at the bottom of a gravity well it's at least a much shallower well than Earth's, and without an appreciable atmosphere rail-gun launches into orbit are entirely feasible.

Moreover fuel is increasingly becoming an anachronism - ion drives blow everything else out of the water in terms of specific impulse, and they don't use fuel - just energy (solar? nuclear?) and a relatively tiny amount of reaction mass, And an ion drive can be designed to use just about anything for mass - some things are better than others, but the stuff that's available locally has a huge advantage.

Is it really that easy? (3, Insightful)

Anonymous Coward | about a year ago | (#44563371)

I know the article talks in relative terms - but changing a massive object's velocity by 58 m/s is not trivial. Also, this assumes the asteroid isn't tumbling or rotating. You would have to cancel this before actually attempting to move the object.

Re:Is it really that easy? (1)

Thanshin (1188877) | about a year ago | (#44563455)

It depends on how you push it. If it's by reflecting solar wind on it via parabolic mirror, you can leave its rotation alone until mining time.

Re:Is it really that easy? (1)

toastar (573882) | about a year ago | (#44564359)

58 m/s is for the calculated impulse delta-v. With a lower thrust maneuver, your total delta-v is higher. This is the problem with ion drives.

Re:Is it really that easy? (0)

Anonymous Coward | about a year ago | (#44563485)

2m to 60m... it should fairly easy!

--An experienced Kerbal Space Program user.

Re:Is it really that easy? (1)

Anonymous Coward | about a year ago | (#44563549)

but changing a massive object's velocity by 58 m/s is not trivial.

That's why they picked 2006 RH120. With a 5m diameter, the mass should be somewhere around 500 tons, probably less. A lot of mass to move, but not impossible, I guess.

Re:Is it really that easy? (1)

taiwanjohn (103839) | about a year ago | (#44563743)

That's well within the capability of a conventional rocket, just in terms of thrust. The problem would be figuring out how to grapple the object and stop its rotation. If it's only 5m wide, you could probably just throw some kind of net around it. I wouldn't be surprised to see plans to capture this particular object starting to appear in the near future.

Re:Is it really that easy? (1)

Captain Hook (923766) | about a year ago | (#44563643)

Also, this assumes the asteroid isn't tumbling or rotating. You would have to cancel this before actually attempting to move the object.

Only if you need to attach 1 big rocket to object being captured.

You could use a gravity tub approach, although it probably needs a small target to work.

Or, you could put lots of smaller rockets all over the surface and just have them fire a quick pulse when they are facing the right way, that would have the added benefit of redundancy should a rocket fail.

Re:Is it really that easy? (1)

morgauxo (974071) | about a year ago | (#44563669)

"They calculate that this could be done with a single burn on 1 February 2021"

This doesn't sound like a relative term to me. And it was even mentioned in the summary too!
I'm not sure I would go so far as to say this means it is objectively easy. I suppose landing a rocket engine on an asteroid and using it to push is something that has never been done before. That alone means there will be challenges to overcome. With only one push necessary though.. that's about as easy as one could realistically imagine is it not?

Re:Is it really that easy? (0)

Anonymous Coward | about a year ago | (#44563705)

some values to proove/disprove: at 2000kg/m3 ( http://en.wikipedia.org/wiki/Standard_asteroid_physical_characteristics#Density ) this would be an impulse of about 13GNs for 58m/s on a 60m asteroid. On a 2m asteroid this drops to about 0.5MNs. According to http://en.wikipedia.org/wiki/Standard_asteroid_physical_characteristics#Density rockets able to provide that impules (not even factoring in the rocket mass) would be a set of 10 space shuttle solid rocket boosters for the 60m asteroid, down to a much more realistic quarter of the rocket used on the apollo launch escape system

Re:Is it really that easy? (1)

Kookus (653170) | about a year ago | (#44563807)

A shuttle is 4 and a half million pounds. and is fighting Earth's gravity. If the largest rock in the summary was picked, it'd weight less than 1 million pounds on Earth (more like half a million).
Changing its velocity by 58m/s is actually technologically trivial. Rotation isn't so bad either, you just pulse your burners. The article just says single burn to give you a nice number.
More than likely, they'd send up 3 - 6 rockets for redundancy and to stabilize the rock's rotation in a few bursts. Then they'd do controlled bursts to change it's velocity. It's rocket science to actually accomplish, but quite trivially done with today's technology.

Re:Is it really that easy? (1)

oPless (63249) | about a year ago | (#44564097)

For $deities sake!

Keep to SI units.

Re:Is it really that easy? (1)

Immerman (2627577) | about a year ago | (#44564505)

In space terms it is - raise something to orbital height and you still need to get it going 8,000m/s to stay up.

It wasn't that long ago... (0)

Anonymous Coward | about a year ago | (#44563389)

... that the military wanted to establish US posts at the Legrange points, when they heard that they were important places in space. See http://www.mail-archive.com/meteorite-list@meteoritecentral.com/msg36443.html

"Mister President - we must not allow an asteroid gap!!"

http://www.youtube.com/watch?v=ybSzoLCCX-Y

Plant Mars (-1)

Anonymous Coward | about a year ago | (#44563437)

God said to plant on Mars.

God says...
C:\TAD\Text\YANKEE.TXT

  Church and noble than a slave has to love and honor
the lash, or a dog has to love and honor the stranger that kicks him!
Why, dear me, _any_ kind of royalty, howsoever modified, _any_ kind
of aristocracy, howsoever pruned, is rightly an insult; but if you
are born and brought up under that sort of arrangement you probably
never find it out for yourself, and don't believe it when somebody
else tells you. It is enough to make a body ashamed of his race
to think of the sort of froth that has always

Easily captured... (3, Interesting)

runeghost (2509522) | about a year ago | (#44563483)

or easily retargeted to hit DC? How long before the politicians demand trillions on behalf of their owners to protect the U.S. from the "asteroid threat". War on Space, here we come!

Re:Easily captured... (2)

Thanshin (1188877) | about a year ago | (#44563551)

An asteroid that size wouldn't reach land.

(However, the US has never needed the threats to be non-fictional to scare its population into giving up freedom and money.)

Re:Easily captured... (1)

AmiMoJo (196126) | about a year ago | (#44564739)

A few of them bunched together, or with a heat shield attached might.

It wouldn't surprise me that much if the first company to capture an asteroid finds all manner of space "junk" headed for it's installation, or perhaps the odd missile from the ground if countries feel threatened enough.

Re:Easily captured... (0)

Anonymous Coward | about a year ago | (#44564021)

How long before the politicians demand trillions ?

Can't we just print them ? Or make a few trillion dollar coins ?

Re:Easily captured... (0)

Anonymous Coward | about a year ago | (#44565017)

Damn loonies, throwing rice.

EROs? (0)

Anonymous Coward | about a year ago | (#44563581)

EROs? There's no shortage of those! I just downloaded several last night!

Re:EROs? (0)

Anonymous Coward | about a year ago | (#44563875)

Why is it all Naruto/Meteor slash-fics!?

58 Second Burn? (2, Insightful)

Dialecticus (1433989) | about a year ago | (#44563599)

And what happens if, due to a malfunction, the thruster doesn't shut off when it's supposed to, and it burns for longer than 58 seconds?

People got angry about BP, and before that the Exxon Valdez, but that was after the accidents had already happened. What happens when a greedy grab for extraterrestrial ore inevitably goes awry? And make no mistake; over the long hault, it is inevitable. Even if the first attempt, hell the first five such attempts, go off without a hitch, there would eventually, over many such attempts, be a critical error on a similar mission.

There would be no time for recriminations and lawsuits then.

Re:58 Second Burn? (1)

Thanshin (1188877) | about a year ago | (#44563617)

And what happens if, due to a malfunction, the thruster doesn't shut off when it's supposed to, and it burns for longer than 58 seconds?

What's your worst case scenario?

OMG! The asteroid hits Earth AND!!!! ... fizzles in a puff of smoke, like the other thousands that hit Earth every day.

Re:58 Second Burn? (0)

Anonymous Coward | about a year ago | (#44563703)

It's a 58m/s change in velocity, actually, carried out in a single burn.

Short answer: limit the fuel.

Re:58 Second Burn? (2)

Errol backfiring (1280012) | about a year ago | (#44563751)

And what happens if, due to a malfunction, the thruster doesn't shut off when it's supposed to, and it burns for longer than 58 seconds?

It would just run out of fuel. It is so expensive to hurl any mass into space that you do not take anything extra with you. The main thing that could go wrong is that the direction of the thrust is wrong or that you blow the asteroid to pieces.

Re:58 Second Burn? (0)

Anonymous Coward | about a year ago | (#44563773)

There are thousands of nuclear weapons on the planet capable of taking out entire cities, and you know what? Nobody has ever accidentally blown up a city with one. You calculate risks, apply appropriate margins, implement fail-safes, and achieve the desired level of safety. Only non-technical people are doomsayers about technology, because anyone who actually understands how engineering works knows what is achievable.

Re:58 Second Burn? (1)

Conspiracy_Of_Doves (236787) | about a year ago | (#44564369)

Accidentally taken out cities with nuclear power plants, sure. Nuclear weapons, no. Never by accident.

Re:58 Second Burn? (4, Informative)

HawkinsD (267367) | about a year ago | (#44563981)

Well, let's consider the damage from the impact of a rocky asteroid, 60m in diameter. Plug this into the excellent Earth Impact Effects program at http://impact.ese.ic.ac.uk/ImpactEffects/. Assume a velocity of 17 km/s, which they say is "typical for asteroids," and an impact angle of 45 degrees.

The calculator says:

        The projectile begins to breakup at an altitude of 54000 meters = 177000 ft
        The projectile bursts into a cloud of fragments at an altitude of 4700 meters = 15400 ft
        The residual velocity of the projectile fragments after the burst is 4.77 km/s = 2.96 miles/s
        The energy of the airburst is 4.52 x 1016 Joules = 1.08 MegaTons.
        No crater is formed, although large fragments may strike the surface.

Clearly you wouldn't want to be right underneath it, but even as close as 20 km, the air blast effects seem rather anticlimactic:

        Peak Overpressure: 18900 Pa = 0.189 bars = 2.69 psi
        Max wind velocity: 41.4 m/s = 92.6 mph
        Sound Intensity: 86 dB (Loud as heavy traffic)
        Damage Description:
                Glass windows will shatter.
                About 30 percent of trees blown down; remainder have some branches and leaves blown off.

So it'd be like BOOM! But not like KA-FOOOM!

For comparison, the Chelyabinsk meteor was estimated at 17-20m, with an airburst energy of 0.4 MegaTons.

Re:58 Second Burn? (2)

Jason Levine (196982) | about a year ago | (#44564119)

And that's if it even hits Earth. If the rockets burn too long they may push the asteroid too far so that it gets flung out to space (gravitational slingshot around Earth). I'll worry if we decide to capture HUGE asteroids on our first go around, but 60 meters large asteroids seem to be an extremely low risk.

Re:58 Second Burn? (1)

robbak (775424) | about a year ago | (#44564239)

They are trying to hit an earth-sun lagrange point. If they do so, the object leaves its solar orbit and enters an unstable earth orbit. They then need to give it another few burns to stabilize the orbit (and keep it away from the lagrange point, which would allow it to leave earth orbit and resume orbiting the sun) . If they miss, then it travels on, on a different orbit, with roughly the same chance of hitting the earth as it ever did.

Re:58 Second Burn? (1)

gman003 (1693318) | about a year ago | (#44564507)

The asteroids being considered are roughly the size of the Chelyabinsk meteor. It's highly unlikely one would make it to the ground. You could still get a similar air-blast, but the odds are pretty good that it won't hit a populated area (remember, three-quarters of the Earth is water).

Re:58 Second Burn? (1)

jasax (1728312) | about a year ago | (#44564567)

To give a practical perspective on meteor sizes, recall that the Chelyabinsk meteor which arrived at Russia this same year had around 15-20 m of diameter
http://en.wikipedia.org/wiki/Chelyabinsk_meteor [wikipedia.org]

And the space rock that carved Meteor Crater (or Barringer crater) in Arizona, around 50 K years ago, had about 40 meters of diameter.
http://www.space.com/834-mystery-arizona-meteor-crater-solved.html [space.com]

So, a 60 meters meteor will probably create a big, big, hole (depending on the velocity at arrival and landing angle) if it falls to Earth. I also remember reading that the impact in Arizona caused much devastation in the surrounding areas, up to several tens of miles from the crater.

Finally, the meteor that "created" the gulf of Mexico and "killed" most of the dinosaurs, about 66 million years ago, had probably around 10 km of diameter.
http://en.wikipedia.org/wiki/Chicxulub_crater [wikipedia.org]

Onward to ruining other stuff (0)

Anonymous Coward | about a year ago | (#44563695)

I guess we've ruined this planet enough now that we can start to export our ruination out into to space to start ruining it.

I wonder when those other civilizations out there are going to start to feel like we are getting just a little bit too capable of escaping our confines and "fixing" that.

http://fc09.deviantart.net/fs70/i/2012/108/e/9/marvin_the_martian_by_profkilljoy7z-d4wnwk4.jpg

Re:Onward to ruining other stuff (0)

Anonymous Coward | about a year ago | (#44563819)

I wonder when those other civilizations out there are going to start to feel like we are getting just a little bit too capable of escaping our confines and "fixing" that.

You mean other civilizations that previously "escaped their confines" are going to "fix" us because we might "escape our confines"?

Re:Onward to ruining other stuff (0)

Anonymous Coward | about a year ago | (#44563849)

Yup. That's how it works. The "master" species/race/civilization/etc. works to keep the others down.

Re:Onward to ruining other stuff (0)

Anonymous Coward | about a year ago | (#44564049)

Yup. That's how it works. The "master" species/race/civilization/etc. works to keep the others down.

The implication of the OP was that "they" were going to "fix us" because we might "export our ruination out into to space to start ruining it."

Re:Onward to ruining other stuff (0)

Anonymous Coward | about a year ago | (#44564597)

Yes. I know what the OP implied as I am the OP.

My implication was that there is a "master species" out there in space that will lock us down (or simply exterminate us) if we threaten to run amok, much like we (the master species on this planet) lock down and/or exterminate inferior species that threaten to run amok and interfere with us.

Re:Onward to ruining other stuff (1)

stiggle (649614) | about a year ago | (#44564803)

"Klaatu Barada Nikto"

Re:Onward to ruining other stuff (2)

Impy the Impiuos Imp (442658) | about a year ago | (#44563851)

We aren't ruining the planet. By all measurements of health, wealth, and longevity, we are doing better than ever before [juliansimon.org] .

The counter-intuitive reality is that, in an economically free society, people will solve problems faster than they become serious. This theory has successfully made predictions over 10 year periods over and over again.

The days of politics as memes figting in your brain should be over.

So yes, death to the false meme that we are ruining the planet, as vector to massive government control of the economy, with attendant slowing of it.

Units ! (0)

Anonymous Coward | about a year ago | (#44563717)

Please, could somebody contact the NASA and remind them that they need to check whether sensors are outputting data in imperial units or metric units or something else ?
If needed, I can write a conversion function in f77 or vb.

Msg-uuid:9F862332-B785-4EC5-8D71-DA1902B56767

Now, just *what POSSIBLY* could go wrong ....??? (1)

tkjtkj (577219) | about a year ago | (#44563757)

This is insane. Let them first develop 100.00000000000%-reliable-accurate-faultless technology before putting the entire planet .. every lifing thing on or above earth .. at serious risk of vaporization. These people ought to be institutionalized ...

Clarkson, you imbicile! (0)

Anonymous Coward | about a year ago | (#44563877)

Hammond!!

Re:Now, just *what POSSIBLY* could go wrong ....?? (2, Insightful)

Anonymous Coward | about a year ago | (#44564011)

Judging by the comments, who would have thought the population of slashdot is 50% luddites. Seriously, this is why you start on small asteroids. A 2m rock is going to burn up in the atmosphere.

Re:Now, just *what POSSIBLY* could go wrong ....?? (2)

DexterIsADog (2954149) | about a year ago | (#44564495)

Thank goodness, a level-headed, rational viewpoint.

Come have a beer with me - drive your 100.00000000000000% reliable and totally safe car to my neighborhood.

Re:Now, just *what POSSIBLY* could go wrong ....?? (1)

Immerman (2627577) | about a year ago | (#44564877)

What risk? Even if we screwed up in the worst possible manner and it collided with the Earth (a vanishingly small probability within the space of all possible screw-ups, most of which would send it sailing merrily past us), a 60m asteroid traveling at roughly the same speed and direction as the Earth would be unlikely to reach the surface to leave a crater. Some fragments might, and you probably wouldn't want to be directly underneath the fireball as it burnt up/detonated in the atmosphere, but even then you'd probably survive all right so long as you didn't get crushed under something knocked over by the blast.

Now if it were traveling at comet speeds it might get exciting (still not civilization ending, but might take out a city if it happened to hit one), but we're bringing in something from our own L4/L5 asteroid fields, and the kinetic energy isn't even remotely comparable.

Re:Now, just *what POSSIBLY* could go wrong ....?? (0)

Anonymous Coward | about a year ago | (#44565045)

You know, before you posted that ignorant rant you should have read the FA or even the comments, because the answer is there. We're not dealing with huge, extinction-event sizes of asteroids. As someone else already said, any asteroid that winds up hitting the Earth will vaporize long before it reaches the ground.

Moderators, the above comment is WAY overrated. Too bad there's no "-1, stupid" mod.

Meteor (2)

rhazz (2853871) | about a year ago | (#44563761)

Can't we just get Sephiroth to use the black materia to summon Meteor? That pulled in an asteroid pretty damn quickly IIRC...

What could possibly go wrong? (0)

Anonymous Coward | about a year ago | (#44563793)

To quote Top Gear, "What could possibly go wrong?"

Stick to spying (0)

Anonymous Coward | about a year ago | (#44563831)

I think the NASA should stick to spying on citizens and leave the space exploration and exploitation to the professionals.

Old NSA meme (0)

Anonymous Coward | about a year ago | (#44564069)

This meme is getting old.

Gn4a (-1)

Anonymous Coward | about a year ago | (#44563843)

Mining water? (2)

Squidlips (1206004) | about a year ago | (#44563979)

I did not know it was such a precious commodity...seems legit.

Re:Mining water? (1)

taiwanjohn (103839) | about a year ago | (#44564067)

Water is extremely precious in space .

new_patent = patent + %term% (1)

Thud457 (234763) | about a year ago | (#44564641)

in space

Oh look, another busted patent pattern.

mmmmmm, now I want Chinese food for lunch so I can have a fortune cookie...

Re:Mining water? (1)

owlstead (636356) | about a year ago | (#44564651)

Oh, yes, thank you for generating another Slashdot meme...

Re:Mining water? (2)

burisch_research (1095299) | about a year ago | (#44564787)

Oh, yes, thank you for generating another Slashdot meme in space

FTFY

Re:Mining water? (1)

Immerman (2627577) | about a year ago | (#44565003)

The SpaceX Falcon Heavy is planned to deliver payload to low Earth orbit for the astoundingly low price of $709/lb. It's maximum payload to geosynchronous transfer orbit is less than half that to LEO (21 vs 53Mg), and I'm guessing the total launch cost is probably about the same, so call it $1800/lb. To Mars the maximum payload is 13Mg, or $2900/lb (which is actually much closer to last-years costs to LEO, so Mars is getting a lot more accessible than it used to be).

At any of those prices though *everything* is precious in space - and in addition to it's more mundane (and vital) uses water can be readily processed into hydrogen peroxide, which is actually a pretty decent rocket fuel. And once we have a source for cheap rocket fuel in space then things can start to really take off.

Re:Mining water? (4, Insightful)

someone1234 (830754) | about a year ago | (#44565277)

It's probably the most precious commodity in space.

Mini moons, and now EROs (0)

Anonymous Coward | about a year ago | (#44564375)

The best part is we have no idea how many there are because with the instruments we have now the chances of detecting an asteroid that small are slim.

So this how the end starts.. (1)

Pendletoncils (2834733) | about a year ago | (#44564677)

In all fairness, it does sound a wee bit like the start of disaster sci-fi movie. An interesting one even. Some asteroids, massive amounts of greed, a cute alien race risking their life and limb for our increasingly idiotic and helpless humanity.
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