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Small Asteroid To Buzz Earth

kdawson posted more than 5 years ago | from the just-a-flesh-wound dept.

Space 171

ddelmonte writes in to tell us about a small near-earth object, discovered just 2 days ago, that is expected to pass within 64,000 km of our planet on March 2, 13:44 UT. NEO 2009 DD45 will be well inside the Moon's orbit and just under twice the altitude of geosynchronous satellites. According to Sky and Telescope, 2009 DD45's closest approach will be over the Pacific west of Tahiti, so observers in Australia, Japan, and perhaps Hawaii will have the best chance of spotting it with, say, an 8-in. telescope. Here's where you can generate an ephemeris of the object for your location. At closest approach NEO 2009 DD45 will be moving half a degree per minute and peaking around magnitude 10.5. It will be brighter than 13th magnitude for only a few hours.

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171 comments

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First... (0, Offtopic)

Anonymous Coward | more than 5 years ago | (#27033257)

AHHHHH!!!!

Second (0, Redundant)

Anonymous Coward | more than 5 years ago | (#27033267)

AHHHHHHHH!!!

Third (0, Redundant)

Anonymous Coward | more than 5 years ago | (#27033285)

AHHHHHHHHHH!!!!!!

Fourth (1, Offtopic)

malkir (1031750) | more than 5 years ago | (#27033335)

C-C-C-COMBO BREAKER

Re:Fourth (3, Funny)

Anonymous Coward | more than 5 years ago | (#27034405)

^That this was modded interesting made me lose faith in humanity.

Piggy ride! (5, Interesting)

Chicken_Kickers (1062164) | more than 5 years ago | (#27033273)

Why can't we send a probe that will land on this asteroid and then piggy ride on it. That way we don't need more fuel to carry it round the solar system. If the asteroid doesn't go where we want, then have a relaunch mechanism for the probe to get off at the most suitable point in the asteroid's orbit.

Impossible in this timespan (5, Informative)

RabidMoose (746680) | more than 5 years ago | (#27033303)

(IANARS) There's simply no way that any space agency could prepare and launch a probe with less than three days notice, and likely no good way to pre-build one without knowing what size/speed asteroid we might be lucky enough to launch at.

Re:Impossible in this timespan (4, Funny)

PolygamousRanchKid (1290638) | more than 5 years ago | (#27033507)

(IANARS) There's simply no way that any space agency could prepare and launch a probe with less than three days notice, and likely no good way to pre-build one without knowing what size/speed asteroid we might be lucky enough to launch at.

I dunno . . . The Thunderbirds seem to be able to get anywhere they want to go, real fast. And Doctor Who just seems to be able to go where ever he damn well pleases, as well.

Re:Impossible in this timespan (4, Funny)

Hurricane78 (562437) | more than 5 years ago | (#27033909)

Unfortunately though, they also have the disadvantage of not being real.

Which is quite unfortunate, in reality.

Re:Impossible in this timespan (1)

dpilot (134227) | more than 5 years ago | (#27034703)

But Dr. Who only gets exactly where he pleases when it satisfies the writers. Most of the time it seems that some sort of space-time vortex sucks him off-course, or the Tardis misbehaves, or other such circumstance landing him in the wrong space/time.

Re:Impossible in this timespan (1)

FatdogHaiku (978357) | more than 5 years ago | (#27034749)

And Doctor Who just seems to be able to go where ever he damn well pleases, as well.

Well sure, once you can go anywhen, it makes it a lot easier to go anywhere. Anyplace was everyplace (and very small to boot) at some point in time, so you go backwards in time until it's all close together, relocate, and then go forward in time staying with your new location...

Re:Impossible in this timespan (5, Funny)

Puffy Director Pants (1242492) | more than 5 years ago | (#27035235)

Dude, if you can make a functional space craft that looks like an English Police box, I'll support your candidacy for head of Nasa.

Re:Impossible in this timespan (4, Interesting)

Nyeerrmm (940927) | more than 5 years ago | (#27034297)

While you're absolutely correct, there is a program known as Operationally Responsive Space (ORS) thats being headed up by DoD rather than NASA that is headed in that direction. I think the time-frame they're considering is closer to 2 weeks, but the general idea is to be able to recognize a need, and design, construct and launch a mission in that period of time. That includes getting adjustable plug-and-play parts (GNC, Power, structures, propulsion) that you can tune and modify quickly to fit the mission profile.

Presumably, a lot of the work to streamline the process of designing the bus and plugging in instruments could be easily translated to space science missions, and if a future opportunity like this were available we could do exactly that. Of course, you'd have to have a pretty interesting guidance system and a very robust structure, since you'd only get an advantage if you stuck the probe in the asteroids path and let it slam into it to get the momentum.

Re:Impossible in this timespan (1)

Pharago (1197161) | more than 5 years ago | (#27035211)

Welcome to the eve-online fitting screen, NASA...what do you want to fly today?

What if it waits in orbit? (2, Interesting)

Mathinker (909784) | more than 5 years ago | (#27037225)

If you had several such pre-built probes waiting in orbit, you would have a much better chance, no? The probes would have the advantage that they're already out of the deepest part of Earth's gravity well, and that you could choose the one whose orbit is best. I would think that with only two or three you would be able to do what he wanted.

OTOH, I'm not convinced it would be cost-effective. Depends on how often do asteroids pass by close enough to make it worth our while (and how often they're worth piggy-backing upon), versus the cost saved for getting where you want to go.

Re:Piggy ride! (4, Insightful)

Anonymous Coward | more than 5 years ago | (#27033309)

You don't save any fuel by being near an asteroid. Putting the probe in the same orbit as the asteroid would have essentially the same fuel cost (actually a little less, because you would not have to overcome the escape velocity of the asteroid).

Re:Piggy ride! (0)

malkir (1031750) | more than 5 years ago | (#27033329)

Uhhhhhhh RTFP "that will land on this asteroid and then piggy ride on it."

Re:Piggy ride! (0)

zappepcs (820751) | more than 5 years ago | (#27033587)

IF you land on it, it will continue to travel without fuel for propulsion for a VERY long time... that could be rather useful

Re:Piggy ride! (4, Informative)

MichaelSmith (789609) | more than 5 years ago | (#27033623)

IF you land on it, it will continue to travel without fuel for propulsion for a VERY long time... that could be rather useful

It you match speeds with it you will continue to travel without fuel for propulsion indefinitely. Being docked to a rock will make no difference. The advantage of having the rock there is that you can mine it for resources and use it as a radiation shield. You could also push transfer momentum to it if you want to change your velocity.

Re:Piggy ride! (4, Informative)

MurphyZero (717692) | more than 5 years ago | (#27034119)

If you could match speeds with it, you could go where it goes without need for the asteroid. Since the asteroid has no propulsion of its own, it's not providing any benefits, if you 'match' speeds (actually velocity, speed and direction). The benefit only comes in matching position and letting the asteroid change the velocity of the spacecraft to match. As long as the spacecraft survives that impact, then it can be used to provide a great momentum transfer.

Re:Piggy ride! (1)

swillden (191260) | more than 5 years ago | (#27034711)

The benefit only comes in matching position and letting the asteroid change the velocity of the spacecraft to match. As long as the spacecraft survives that impact, then it can be used to provide a great momentum transfer.

Gigantic. Bungee.

Brilliant, huh?

Re:Piggy ride! (2, Interesting)

radtea (464814) | more than 5 years ago | (#27034937)

Gigantic. Bungee.

This is actually not completely insane. Just dumping some guesses at "reasonable" parameters into a dumb-as-rocks bit of Python to simulate the encounter, a bungee with a relaxed length of 1000 km and a spring constant of 10^-3 N/m would do the job with a peak acceleration of about 160 g assuming 50 km/s delta-v. Total acceleration time is about 100 seconds, and the bungee stretches out to about two and a half times its relaxed length.

If you had a material that would stretch up to 10 times its relaxed length you could keep the peak acceleration down to about 25 g!

These calculations assume the asteroid is much more massive than the probe--if it is not then the numbers actually get a bit better, as the asteroid slows down a bit as the probe accelerates.

In any case, I wouldn't rule this out. Hardened instruments can take insanely high accelerations, and materials are getting more incredible all the time.

Re:Piggy ride! (2, Funny)

swillden (191260) | more than 5 years ago | (#27035257)

a bungee with a relaxed length of 1000 km and a spring constant of 10^-3 N/m would do the job with a peak acceleration of about 160 g assuming 50 km/s delta-v. Total acceleration time is about 100 seconds, and the bungee stretches out to about two and a half times its relaxed length.

:-)

Of course, then there are the issues of getting a 1000 km bungee up there, and figuring out how to lasso the asteroid.

Re:Piggy ride! (2, Interesting)

retchdog (1319261) | more than 5 years ago | (#27036161)

It's not crazy at all: http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion) [wikipedia.org]

Compared to using pneumatic springs to harness and dampen the force of exploding atomic bombs in order to propel a manned craft, coupling to an asteroid is downright quaint.

Re:Piggy ride! (1)

LingNoi (1066278) | more than 5 years ago | (#27034879)

Could be useful for mining out, then you have a massive deathstar spaceship made out of rock.

Re:Piggy ride! (0)

Anonymous Coward | more than 5 years ago | (#27036611)

Thanks for restating exactly what the post you replied to said.

Re:Piggy ride! (1)

apostrophesemicolon (816454) | more than 5 years ago | (#27036059)

seeing as matching speed and then land is irrelevant, then the only beneficial way is to shoot the probe onto the asteroid right as it passes.
I understand that the error margin is very much less, not to mention the risk of damaging the instrument upon impact. But if we're to take advantage of both the momentum of the asteroid and the opportunity to study it, this is the way to go.

Re:Piggy ride! (1)

mustafap (452510) | more than 5 years ago | (#27033879)

You need to re-think this one a little bit. What propulsion source do you think the asteriod has that a satellite landing on it doesn't?

Re:Piggy ride! (0)

rhyder128k (1051042) | more than 5 years ago | (#27034523)

Surely the asteroid has considerable inertia due to its mass? A probe would have to apply thrust to overcome gravity wells that it encounters. The asteroid will be affected by the "drag" of passing close to large bodies but already has considerable ineria.

Let's say that I sent a ping pong ball, a house brick, and a 20t lump of iron heading away from earth at 5 m/s. I would expect the ping pong ball to slow most quickly, followed by the house brick. In some situations, the lump of iron might be able to escape where the others would not. You'd experience the same effect if you tried to stop a car rolling down hill a ten miles per hour and then compared it to stopping a skate board moving at the same speed. Perhaps I'm missing something?

In addition, a probe on top of an asteroid benefits from at least some protection from collisions.

Re:Piggy ride! (2, Insightful)

Meumeu (848638) | more than 5 years ago | (#27034659)

Surely the asteroid has considerable inertia due to its mass? A probe would have to apply thrust to overcome gravity wells that it encounters. The asteroid will be affected by the "drag" of passing close to large bodies but already has considerable ineria.

Let's say that I sent a ping pong ball, a house brick, and a 20t lump of iron heading away from earth at 5 m/s. I would expect the ping pong ball to slow most quickly, followed by the house brick. In some situations, the lump of iron might be able to escape where the others would not. You'd experience the same effect if you tried to stop a car rolling down hill a ten miles per hour and then compared it to stopping a skate board moving at the same speed. Perhaps I'm missing something?

Yes, you're missing the basics of physics... This whole post is pretty much bullshit.

Re:Piggy ride! (3, Informative)

meringuoid (568297) | more than 5 years ago | (#27034907)

Let's say that I sent a ping pong ball, a house brick, and a 20t lump of iron heading away from earth at 5 m/s. I would expect the ping pong ball to slow most quickly, followed by the house brick. In some situations, the lump of iron might be able to escape where the others would not. You'd experience the same effect if you tried to stop a car rolling down hill a ten miles per hour and then compared it to stopping a skate board moving at the same speed. Perhaps I'm missing something?

Yeah. No friction or air resistance in space, that's what you're missing. Oh, and all of physics since Galileo, you're missing that too.

The brick has less mass than the iron lump, true - and so it has proportionately less inertia. But the gravitational force on the brick is also less than that of the iron lump, by the same proportion. The two cancel out. If they have the same velocity, then if one escapes, so does the other. It's the same principle as how a brick will fall at the same speed as a feather, if dropped in a vacuum.

Similarly, if a spaceprobe and an asteroid fly away from the Earth at the same velocity, it doesn't matter whether they're attached or separate: both will follow the same path.

Re:Piggy ride! (1)

nacturation (646836) | more than 5 years ago | (#27036619)

Solar wind?

Re:Piggy ride! (3, Informative)

CrimsonAvenger (580665) | more than 5 years ago | (#27036119)

Let's say that I sent a ping pong ball, a house brick, and a 20t lump of iron heading away from earth at 5 m/s. I would expect the ping pong ball to slow most quickly, followed by the house brick. In some situations, the lump of iron might be able to escape where the others would not. You'd experience the same effect if you tried to stop a car rolling down hill a ten miles per hour and then compared it to stopping a skate board moving at the same speed. Perhaps I'm missing something?

Have you read anything by this guy Newton? Fig, or Isaac, one of the two. He pretty much explained (about 300 years ago) how this whole "gravity" thing works.

And, for what's it's worth, 5 miles/second (I shudder to think you might have meant metres/second) is below escape velocity. It's barely above orbital velocity. So not even your lump of iron would escape. Even if gravity worked they way you think it does, as opposed to the way it really does.

Re:Piggy ride! (1)

rhyder128k (1051042) | more than 5 years ago | (#27036195)

OK, OK. Looks like a made mistake on that one. Although, I did phrase my point as a question, as I'm no expert on space science. My mistake.

Re:Piggy ride! (1)

Provocateur (133110) | more than 5 years ago | (#27036967)

Well, if you go by his sig, he'll still defend you to death...right? Right? Hello? hmmm, seems like he left...

Re:Piggy ride! (3, Insightful)

evanbd (210358) | more than 5 years ago | (#27033323)

Having the asteroid there doesn't change anything, really. It costs the same amount of delta-v to put a probe on that orbit whether or not there's an asteroid (at least for tiny rocks like this; it would have to be getting toward small moon size to matter much). You already don't need propellant to carry a probe around the system -- things in space just coast, following an orbit determined by gravity. The hard part is getting it onto the right trajectory, not keeping it there.

Re:Piggy ride! (1)

MichaelSmith (789609) | more than 5 years ago | (#27033395)

With a thirty metre object you could almost snare it with a net. Then you would need a shock absorbing tether to match velocities. Given that materials for tethers are improving all the time, and that high tech space drives are not inventing themselves the way they do on star trek, I wonder if this could be a practical way to travel around the inner solar system

Re:Piggy ride! (2, Interesting)

CrimsonAvenger (580665) | more than 5 years ago | (#27036017)

With a thirty metre object you could almost snare it with a net. Then you would need a shock absorbing tether to match velocities.

It's a 30 metre object moving well over escape velocity. You snag it with the net, and then endure 9000 gravities acceleration, and in only a tenth of a second, you've matched orbits.

If your tether will stretch to a length of 450 metres while holding a weight (you, or a satellite your size) of about 2000 tons.

Good luck with that.

Given that materials for tethers are improving all the time, and that high tech space drives are not inventing themselves the way they do on star trek, I wonder if this could be a practical way to travel around the inner solar system

In a word, no. If you want more words, "practical" doesn't begin to describe this notion.

Re:Piggy ride! (0)

Anonymous Coward | more than 5 years ago | (#27033405)

Well, when I first saw the comment, I was thinking 'uh, that's not going to work' - because you need to accelerate to the asteroids speed to land on it.
But then, I was thinking, what we really need is some sort of giant elastic bungee cord!

What if (1)

markov_chain (202465) | more than 5 years ago | (#27033445)

Suppose the main (heavy) probe was sitting in GEO or something, but shot a lightweight harpoon into the meteor's orbit. Then the trick would be to get the tether to pay out quickly, and the main probe to slowly increase tension so it can accelerate into the meteor's orbit.

Re:What if (1)

evanbd (210358) | more than 5 years ago | (#27033579)

If you can only manage a few hundred m/s speed difference between the two, it's probably not worth doing -- rockets to provide that much delta-v just aren't that large or heavy, and this would be complicated, heavy, and new. If you want to do more than that, then you have a whole different problem -- making a harpoon work at several km/s sounds nontrivial, never mind the cable payout system or the mass of a cable that long (unless your probe can handle ridiculous accelerations, 1/2*a*t^2 means you have a very long -- aka heavy -- cable).

Re:What if (1)

History's Coming To (1059484) | more than 5 years ago | (#27034411)

There's a good description of that kind of maneuver in "Wheelers" http://bookshop.blackwell.co.uk/jsp/search_results.jsp?wcp=1&quicksearch=1&cntType=&searchType=keywords&searchData=9780743429023&x=0&y=0 [blackwell.co.uk] by Ian Stewart and Jack Cohen. Except they use rocks fired from linear accelerators on the moon, but the same net-and-shock-absorber concept.

Re:Piggy ride! (5, Insightful)

amorsen (7485) | more than 5 years ago | (#27033325)

Why can't we send a probe that will land on this asteroid and then piggy ride on it.

"Landing" would either actually be "crashing at a speed measured in km/s" or would require just as much fuel as going in the same orbit without the asteroid, and then what's the point...

Re:Piggy ride! (4, Informative)

CrimsonAvenger (580665) | more than 5 years ago | (#27033381)

Why can't we send a probe that will land on this asteroid and then piggy ride on it. That way we don't need more fuel to carry it round the solar system. If the asteroid doesn't go where we want, then have a relaunch mechanism for the probe to get off at the most suitable point in the asteroid's orbit.

If we have the deltaV to land on the rock, then we have the deltaV to match its orbit without bothering to land on it. So why waste time with the landing?

Or were you thinking that little or no deltaV would be required because the rock was passing close by?

Well, no, a quick guesstimate based on the limited information in the article has it passing at about 9km/s relative to Earth, at 64000km altitude. Which is rather more than escape speed. About 8500 m/s over Earth escape speed, in fact. We've sent probes out faster than that a few times. The stuff that goes out past Jupiter, for instance. But it's a non-trivial exercise.

Re:Piggy ride! (4, Informative)

meringuoid (568297) | more than 5 years ago | (#27033719)

Why can't we send a probe that will land on this asteroid and then piggy ride on it.

Physics doesn't work that way.

You seem to think it's like hopping on the back of an old London bus: grab it as it passes and jump up onto the step. But speeds in space are far greater than that. If you try to catch an asteroid as it passes, words like 'splat' or 'crunch' are appropriate. You need to match the asteroid's velocity very closely in order to land on it without being destroyed - and if you can do that, then you're on the same orbit as the asteroid anyway, and you'll go where it goes whether you land or not. So you don't actually need the asteroid to be there.

I suppose you might arrange something cunning with a big net and a lot of bungee rope, if you can pull off an incredibly accurate flight plan, but even so it's unlikely that the asteroid is going to be near any other targets of interest in the near future; it's more worth your while to load up the extra fuel needed to fly direct to the planet or moon you want to study.

Re:Piggy ride! (3, Interesting)

pcolaman (1208838) | more than 5 years ago | (#27034269)

I vote we shoot it down, just to see if we can do it. That would be more fun, anyways. I nominate myself to push the button.

Re:Piggy ride! (2, Insightful)

MrMista_B (891430) | more than 5 years ago | (#27034427)

Well...

Landing a probe on an asteroid passing by at this speed, would be like trying to catch a bullet with your bare hands.

I'd say the mental imagery is pretty close to accurate, in both cases.

Re:Piggy ride! (1)

lpzie (925253) | more than 5 years ago | (#27035947)

I'm sensing a Watchmen reference.

Re:Piggy ride! (1)

CrimsonAvenger (580665) | more than 5 years ago | (#27036055)

Landing a probe on an asteroid passing by at this speed, would be like trying to catch a bullet with your bare hands.

Good imagery. Note that the the rock is moving about five times as fast (relative to Earth) as the fastest bullet.

Re:Piggy ride! (0)

Anonymous Coward | more than 5 years ago | (#27034939)

Yeah, well done. Why don't we ask Michael Bay if he's interested in contributing to your pathetic attempt at a response. We can even see if Liv Tyler and that face scrotum looking fella to come along for the ride as well.

Re:Piggy ride! (1)

Workaphobia (931620) | more than 5 years ago | (#27035051)

I think the notion of relative velocities is enough to eliminate that prospect entirely. If you don't match velocities with the object your piggybacking onto, you're crashing into it. If you do match speeds, then what was the point of the piggybacking in the first place?

Re:Piggy ride! (0)

Anonymous Coward | more than 5 years ago | (#27036101)

it will not save fuel. Once the prob is in an orbit, say one that matches the astroid's orbit, it doesn't need any fuel to stay there.......CAS

Thirty metres (0)

Anonymous Coward | more than 5 years ago | (#27033327)

The Tunguska object would have been about that size. The article compares it to the October 7 2008 object, which was only a couple of metres across. Thats why it didn't get much attention.

Re:Thirty metres (2, Informative)

MichaelSmith (789609) | more than 5 years ago | (#27033639)

That was me. Must have hit AC by mistake.

Re:Thirty metres (2, Funny)

Hooya (518216) | more than 5 years ago | (#27034165)

> That was me. Must have hit AC by mistake

No, no.. the meteor didn't hit anything.. but thanks for flying by if it indeed was you.

Another perspective (1, Informative)

wjh31 (1372867) | more than 5 years ago | (#27033343)

radius of the earth is 6400km, so it will be at ten times the radius of the earth. It will experiance an acceleration from the earth of about 0.1m/s^2. In those few hours it will be greater than 13th magnitude it's velocity will change by about 1km/s or ~30000km/h from the force of the earth alone.

Re:Another perspective (2, Interesting)

MichaelSmith (789609) | more than 5 years ago | (#27033407)

In those few hours it will be greater than 13th magnitude it's velocity will change by about 1km/s or ~30000km/h from the force of the earth alone.

Most of which it will give back on the way out. So what is the net velocity change for the earth encounter?

Re:Another perspective (2, Insightful)

wjh31 (1372867) | more than 5 years ago | (#27033549)

about Zero when integrated over enough orbits, but for this encounter, while the speed wont change by then end of the encounter, but the velocity will, i think

Re:Another perspective (1)

John Hasler (414242) | more than 5 years ago | (#27034087)

There will be a significant change in direction. How much kinetic energy it gains or loses depends on the details.

Re:Another perspective (2, Insightful)

Overzeetop (214511) | more than 5 years ago | (#27033965)

m2/m1xdelta-v, or diminishingly small; that's the useful part about using planetary passes to change velocity - they affect the planet in a negligible way. Kind of like driving to the store makes a negligible change in the CO2 in the atmosphere vs. walking. If all the asteroids started going for a joy ride, or taking vacation past earth every summer just for the fun of it, we'd start to notice. ;-)

Re:Another perspective (5, Informative)

MartinSchou (1360093) | more than 5 years ago | (#27033761)

1 km/s is EXACTLY 3,600 km/h. Not roughly 30,000 km/h as you suggest.

A potential 3rd moon? (2, Interesting)

pecosdave (536896) | more than 5 years ago | (#27033427)

Assuming of course you count Cruithne [wikipedia.org] as a moon. What happens once it passes our gravity?

Re:A potential 3rd moon? (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#27033757)

Assuming of course you count Cruithne [wikipedia.org] as a moon. What happens once it passes our gravity?

You mean this Cruithne [sturly.com] moon, right?

Parent links to malicious site (3, Informative)

Anonymous Coward | more than 5 years ago | (#27033859)

Sturly is a redirection service similar to tinyurl. Luckily it provides a preview. The link wants to send you to the same "dragonslair" link that appeared in the 3D game without polygons story from earlier today.

Looking at the source of the page, it attempts to download a movie on eDonkey, change your AIM name, send off spam emails, open up lots more windows, and probably much more. It also moves the window around so you can't close it, and pops up messages when you try to alt+f4.

In short; DO NOT CLICK THE LINK.

Re:A potential 3rd moon? (1)

MartinSchou (1360093) | more than 5 years ago | (#27033819)

5th, actually [wikipedia.org]

Known satelittes and quasi-satellites wrt Earth

Moon
Cruithne (Earth's first known quasi-satellites)
2003 YN107
(164207) 2004 GU9

Re:A potential 3rd moon? (1)

madcat2c (1292296) | more than 5 years ago | (#27035527)

Since its Diameter is 5Km, i would guess no.

another asteroid...another day (1)

mikey177 (1426171) | more than 5 years ago | (#27033429)

they say that asteroids this size hit earth every month without any notice. I would be more worried about comets that we cant pick up till it gets closer to the sun and at that point if it is headed towards earth you only have around 6 months to a year

Re:another asteroid...another day (0)

Anonymous Coward | more than 5 years ago | (#27033581)

It seems like with 6 months to a year's notice, NASA and the DoD would have a good chance of hitting it with whatever secret uber-nukes the US has hidden away.

Does anyone know how feasible or likely that scenario is?

Re:another asteroid...another day (1)

rubycodez (864176) | more than 5 years ago | (#27035161)

the U.S. has no such thing, the biggest bomb ever was soviet made

Re:another asteroid...another day (1)

madcat2c (1292296) | more than 5 years ago | (#27035693)

Lord knows the U.S. couldn't hide [wikipedia.org] something of extreme military importance.

Re:another asteroid...another day (1)

rubycodez (864176) | more than 5 years ago | (#27036077)

hide mostly meant "keep officially declared", plenty of early sightings of that bird.

But very large nukes such as that Tsar bomb can't be put on even the largest of our rockets, just too damn heavy.

Re:another asteroid...another day (1)

CrimsonAvenger (580665) | more than 5 years ago | (#27036259)

the U.S. has no such thing, the biggest bomb ever was soviet made

The biggest ever detonated was Soviet made. I'm not sure who would know what the biggest ever built was, but I doubt seriously it's any of us.

And besides, a 15 MT bomb would do nicely here. And we have those.

Unless we decommissioned them as part of one of the SALTs. Anyone know?

Re:another asteroid...another day (1)

CrimsonAvenger (580665) | more than 5 years ago | (#27036283)

"it won't be another Vietnam" -- Rummy

Vietnam - ten years, 50,000 dead.

Iraq - six years, less than 5000 dead.

Looks like he was right.

Re:another asteroid...another day (0)

Anonymous Coward | more than 5 years ago | (#27037021)

How can you possibly say what the US has "hidden away". It's not as if they'd make their best stuff public knowledge.

obligatory (2, Funny)

Anonymous Coward | more than 5 years ago | (#27033605)

/ducks

Buzz vs. Non-buzz (5, Informative)

DynaSoar (714234) | more than 5 years ago | (#27033619)

Three days notice. 20 to 50 meter diameter. Assume it's dense rock and a vertical impact trajectory into the ocean (avg. 1000 m depth).

Impact energy 116 kT to 1.8 MT. Very near the lowest energy potential impact of the known NEOs, actually. Not relevant here since the object quite clearly misses. But if and when one doesn't miss, someplace is going to catch a small to medium nuke sized blast, and there won't be time to do squat about it.

My money says we'll have the capability to defend ourselves against such an impact. The second time.

Re:Buzz vs. Non-buzz (1)

MichaelSmith (789609) | more than 5 years ago | (#27033703)

I have this idea in my head about a space transportation system based around tethers, solar sails and aerobraking. There are a lot of tricks you could do once attached to an object like this. You could convert angular momentum from the object into linear momentum by letting the asteroid swing you around then releasing at the appropriate moment. You could do a slingshot by pushing off the asteroid then retracting the tether at the appropriate moment.

It could be a very hairy but profitable way to travel.

Re:Buzz vs. Non-buzz (1)

meringuoid (568297) | more than 5 years ago | (#27033769)

My money says we'll have the capability to defend ourselves against such an impact. The second time.

We won't do anything about these things till there's a loss of life. There's a 70% chance it hits the ocean, and with 1MT energy? There's pretty good odds it will go unnoticed by anything but defence satellites.

I'd guess we'll get near miss after near miss, we'll ignore Tunguska-scale impacts at sea and in the tundra and in the desert just like we ignored Shoemaker-Levy 9... Nobody will fund a serious defence until one of these things strikes a city.

Re:Buzz vs. Non-buzz (1)

MichaelSmith (789609) | more than 5 years ago | (#27033791)

just like we ignored Shoemaker-Levy 9...

In what way did we ignore Shoemaker-Levy 9? That wasn't our planet after all.

Re:Buzz vs. Non-buzz (2, Insightful)

Frequency Domain (601421) | more than 5 years ago | (#27036855)

We won't do anything about these things till there's a loss of life. There's a 70% chance it hits the ocean, and with 1MT energy? There's pretty good odds it will go unnoticed by anything but defence satellites.

You think sea strikes are harmless? The odds of actually hitting a city are pretty small, but the odds of hitting a chunk of water near enough to populated areas to cause tsunami damage are much larger since, according to NOAA [noaa.gov] , coastal counties in the continental US account for only 17% of land area but have 53% of the population. Imagine what a 10m or more surge from a tsunami could do to the Netherlands, or Miami, or New York. For comparison purposes, the Sumatra tsunami of 2004 was estimated to release around 20MT of energy at the surface, and produced as much as 30m surges hundreds of miles away from the epicenter.

Re:Buzz vs. Non-buzz (1)

R3d M3rcury (871886) | more than 5 years ago | (#27037249)

For comparison purposes, the Sumatra tsunami of 2004 was estimated to release around 20MT of energy at the surface, and produced as much as 30m surges hundreds of miles away from the epicenter.

Okay. So that's 20 times the 1MT we're talking about. So that would be 1.5m surge.

I think New York is safe.

Re:Buzz vs. Non-buzz (3, Funny)

narcberry (1328009) | more than 5 years ago | (#27034473)

There's only so much matter, after enough time, we don't have to worry about anymore collisions.

I vote we wait it out.

Small english/metric error, I believe (1)

scotts13 (1371443) | more than 5 years ago | (#27033773)

The slashdot post says twice the altitude of geosynchronous satellites. Maybe, but only if it was 32,000 miles, not kilometers. Geosynchronous orbit is 32,000 miles; this object will be at about 40,000 miles as correctly stated in the original article. Should be amended to remove geosynchronous, or to "just beyond geosynchronous orbit."

Re:Small english/metric error, I believe (2, Informative)

John Hasler (414242) | more than 5 years ago | (#27033951)

> Geosynchronous orbit is 32,000 miles...

Geosynchronous orbit is 22,236 miles.

Re:Small english/metric error, I believe (0)

tux0r (604835) | more than 5 years ago | (#27034189)

> Geosynchronous orbit is 32,000 miles...

Geosynchronous orbit is 22,236 miles.

[citation needed] [centennialofflight.gov]

Surely the refutation is no more helpful to the reader if it's just your word against GP's...? :)

Re:Small english/metric error, I believe (1)

maxume (22995) | more than 5 years ago | (#27035479)

It depends on which one is correct.

If the potential correction contains accurate information, it is far more helpful to the reader than the incorrect information, citation or not (even if all it does is prompt the reader to obtain a reliable source for the information).

This is ghostwriter asking for Permission to Buzz (1)

Joe The Dragon (967727) | more than 5 years ago | (#27033815)

This is ghostwriter asking for Permission to Buzz the Earth.

Re:This is ghostwriter asking for Permission to Bu (1, Informative)

Anonymous Coward | more than 5 years ago | (#27034353)

I think it was supposed to be Ghostrider. As in, from "Ghostriders in the sky."

Negative Ghostrider, pattern is full. .....

GODDAMMIT!

Armageddon (3, Funny)

Samah (729132) | more than 5 years ago | (#27033907)

Quick, someone notify Bruce Willis!

Holy Crap! (1)

binaryseraph (955557) | more than 5 years ago | (#27034169)

quick where is the kool-aid?!

Close call (4, Interesting)

mc1138 (718275) | more than 5 years ago | (#27034377)

While right now 64,000 puts it fairly far out in terms of all the junk orbiting the earth, it is significantly closer than the moon is. Even if it still missed the earth, just a few thousand kilometers closer and it could reek havoc on all the man-made junk spinning around the Earth. How much potential damage/debris could that cause?

Re:Close call (2, Insightful)

Nyeerrmm (940927) | more than 5 years ago | (#27034679)

Without any actual analysis, I'll go out on a limb and estimate it would cause as much havoc as any large man-made piece of junk out there, like say a dead Soviet satellite. A much larger asteroid would be a different story, since not only would it have a larger footprint, but would also have hard-to-predict gravitational effects on all the satellites that got too near it. Of course, we're doing a pretty good job of detecting larger NEOs now... Apophis is the most problematic, mostly because we simply don't have high enough precision knowledge of its position to know where it will be in 2029 and 2036.

Re:Close call (1)

swillden (191260) | more than 5 years ago | (#27034739)

Apophis is the most problematic, mostly because we simply don't have high enough precision knowledge of its position to know where it will be in 2029 and 2036.

Well, that and its habit of enslaving humans to feed its goa'uld power trip fantasies.

Re:Close call (0)

Anonymous Coward | more than 5 years ago | (#27034843)

Ummm, speaking of dead Soviet satellites, how many of them are still in some sort of Molyniya orbit (sorry about the probably misspelling - I'm referring to the highly ellipitical orbits) ?

ISTR there were even some ham satellites that were launched into highly elliptical orbits that were "visible" for 10-12 hours/day from one hemisphere or the other, so I'm sure they were wayyyyy up there somewhere.

Re:A good use of the Gov't Money (1)

antirelic (1030688) | more than 5 years ago | (#27035677)

Let me ask the resident experts: With all the different telescopes that litter the earth, how is it that we miss these types of objects coming so close to our planet? I know that space is vast (practically beyond rational imagination), but is there a way to observe a region of space encompassing several days/weeks/months with objects traveling at a certain speed? What would those costs be? (I bet it would be under 700 Billion USD)

I found this article pretty interesting about a space based constellaton of satellites using radar to track objects on the ground. How about something like this pointing away from earth?:
http://www.globalsecurity.org/space/systems/sr.htm [globalsecurity.org]

I think this would be an excellent time for the US to jump back in the lead in science and technology. Take that money going into ideologically based spending, and shove it into space systems that will have actual use. Create methods of early detection of earth impacting objects, and standby means to intercept. The "space industrial complex" could lead to high tech jobs that create a high tech industry that will attract top talent from around the world at rates that rival the early 20th century.

Re:A good use of the Gov't Money (1)

John Hasler (414242) | more than 5 years ago | (#27036157)

It is going to require an 8" telescope to see it at 64,000 km. Brightness is inversely proportional to the square of distance. Extrapolate.

Re:Close call (0)

Anonymous Coward | more than 5 years ago | (#27037309)

Even if it still missed the earth, just a few thousand kilometers closer and it could reek havoc on all the man-made junk spinning around the Earth.

Thank god that in space, no one can smell you. Whew.

Another one from Klendathu... (3, Funny)

allcoolnameswheretak (1102727) | more than 5 years ago | (#27034477)

Their aim is getting better. They will hit us eventually if we don't do something about those Bugs, soon.

So, I used a calc on the impact (5, Informative)

Ralph Spoilsport (673134) | more than 5 years ago | (#27034573)

the calculator can be found here:
http://www.lpl.arizona.edu/impacteffects/ [arizona.edu]

And the results are (assumed that you are 2000km from impact - if it hit it would be in the ocean...)

Your Inputs: Distance from Impact: 2000.00 km = 1242.00 miles
Projectile Diameter: 30.00 m = 98.40 ft = 0.02 miles
Projectile Density: 8000 kg/m3
Impact Velocity: 17.00 km/s = 10.56 miles/s
Impact Angle: 90 degrees
Target Density: 1000 kg/m3
Target Type: Liquid Water of depth 100.00
meters, over typical rock.

Energy: Energy before atmospheric entry: 1.63 x 1016 Joules = 3.90 MegaTons TNT
The average interval between impacts of this size somewhere on Earth is 314.0 years

Atmospheric Entry: The projectile begins to breakup at an altitude of 14100 meters = 46100 ft
The projectile reaches the ground in a broken condition. The mass of projectile strikes the surface at velocity 10.8 km/s = 6.7 miles/s The impact energy is 6.58 x 1015 Joules = 1.57 MegaTons.
The broken projectile fragments strike the ground in an ellipse of dimension 0.151 km by 0.151 km

Major Global Changes: The Earth is not strongly disturbed by the impact and loses negligible mass.
The impact does not make a noticeable change in the Earth's rotation period or the tilt of its axis.
The impact does not shift the Earth's orbit noticeably.

Crater Dimensions:
What does this mean?

The crater opened in the water has a diameter of 1.4 km = 0.866 miles
For the crater formed in the seafloor: Crater shape is normal in spite of atmospheric crushing; fragments are not significantly dispersed.
Transient Crater Diameter: 670 m = 2200 ft
Transient Crater Depth: 237 m = 777 ft
Final Crater Diameter: 837 m = 2750 ft
Final Crater Depth: 179 m = 586 ft

The crater formed is a simple crater
The floor of the crater is underlain by a lens of broken rock debris (breccia) with a maximum thickness of 82.8 m = 272 ft.
At this impact velocity ( Thermal Radiation: What does this mean?

At this impact velocity ( Seismic Effects: What does this mean?

The major seismic shaking will arrive at approximately 400 seconds.
Richter Scale Magnitude: 4.4
Mercalli Scale Intensity at a distance of 2000 km:
Nothing would be felt. However, seismic equipment may still detect the shaking.

I for one... (1)

fullymodo (985789) | more than 5 years ago | (#27035153)

...welcome our new 45 double-D overlords.
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