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Rosetta, the Comet Hunter

Cliff posted more than 10 years ago | from the harpooning-comets dept.

Space 132

Roland Piquepaille writes: "After being delayed for about a year because of a failure of the Ariane-5 rocket, the Rosetta spacecraft is scheduled to be launched on February 26. Rosetta is a special spacecraft, including an orbiter and a lander. And it will take up to 2014 before landing on Comet 67P/Churyumov-Gerasimenko -- with the help of a harpoon. Then, as says the European Space Agency (ESA), Rosetta will help to solve planetary mysteries. This news release looks at the goals of Rosetta's mission and explains why it will take more than ten years to reach the comet. But here the 'funny' part of the story: the landing. 'In November 2014, the lander will be ejected from the spacecraft from a height which could be as low as one kilometre. Touchdown will be at walking speed, about one metre per second. Immediately after touchdown, the lander will fire a harpoon into the ground to avoid bouncing off the surface back into space, since the comet's extremely weak gravity alone would not hold onto the lander.' This overview contains more details and includes illustrations of the Rosetta's spacecraft and its landing on the comet."

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132 comments

Uh, (-1, Redundant)

Anonymous Coward | more than 10 years ago | (#8146600)

where are all the white women at?

this comment has been moved (-1, Redundant)

Anonymous Coward | more than 10 years ago | (#8146609)

bitch

Re:Uh, (-1, Redundant)

Anonymous Coward | more than 10 years ago | (#8146617)

hello anonymous coward... what's happening?

uhhhhh... we got sort of a problem here... yeaah... you appearantly didn't put one of the new GNAA advertisements on your first post.

mmmh... yeahh.. you see, we're putting the GNAA advertisements on all first posts now before they go out. did you see the memo about this?

so if you could just go ahead and make sure you do that from now on, that would be great.

and i'll go ahead and make sure you get another copy of that text. mmmmkay?

Re:Uh, (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8146739)

I enjoyed that scene too.

in my pants, of course (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8146678)

Some idiot moderator is a little too Redundant happy.

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Re:in my pants, of course (0)

Anonymous Coward | more than 10 years ago | (#8146697)

But I don't wanna work in SourceForge sales. I imagine selling a free product is pretty hard.

Oreos up my ass (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8146740)

Is it the whole cookie, and just the creamy center? I imagine if it is just the creamy center, then the number is greater than 3x the number of whole cookies that would fit. Please advise.

the whole cookie (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8146835)

As part of the interview process, applicants are required to cram oreos up their assholes, mash them up with their sphincter muscles, and defecate them into Cowboy Neal's mouth.

As we all know, no amount of oreos will satisfy that fat fuck, so the test screens out all but the largest rectal cavities.

Re:the whole cookie (0)

Anonymous Coward | more than 10 years ago | (#8146888)

Y'know, for a troll, that was actually kind of funny. Well the first sentence anyways. I wonder how much force it takes to crush an Oreo anyways... ?
Ah well, don't mind me. Mod the thing down into hell, i've had my laugh.

Sounds like how I get dates (4, Funny)

corebreech (469871) | more than 10 years ago | (#8146605)

Harpoon... check

Name I can't pronounce... check

10 years before getting some... check

I just have the class not to make a big deal out of it.

what the hell? (0)

Anonymous Coward | more than 10 years ago | (#8146769)

are you saying you cant pronounce rosetta?
girls are the least of your problems...

Re:what the hell? (0)

Anonymous Coward | more than 10 years ago | (#8147574)

"girls are the least of your problems..."

Apparently thats not true for your Mom. I humped her last night!

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Phase 2 (3, Funny)

AtariAmarok (451306) | more than 10 years ago | (#8146615)

Phase 2 will be sending Bruce Willis and the rest of his rigger pals in their awful corduroy space-suits to "kick comet ass" of all the ones found by Rosetta.

Re:Phase 2 (0)

Anonymous Coward | more than 10 years ago | (#8146785)

Yes. Score 4, funny. Hah. Intelligent humor.

Dumbass.

Please tell me... (1)

jesterzog (189797) | more than 10 years ago | (#8147502)

Phase 2 will be sending Bruce Willis and the rest of his rigger pals in their awful corduroy space-suits to "kick comet ass" of all the ones found by Rosetta.

...that we can leave them there.

Gravity? (5, Interesting)

Moderator (189749) | more than 10 years ago | (#8146618)

The timeline states that in 2014, Rosetta will orbit the comet for six months before it lands, mapping the comet to find a suitable landing spot. Then it goes on to say:
Immediately after touchdown, the lander will fire a harpoon into the ground to avoid bouncing off the surface back into space, since the comet's extremely weak gravity alone would not hold onto the lander..

My question is, if the comet's gravity is so weak, how is the Rosetta supposed to orbit this thing for six months?

Re:Gravity? (1)

Mr2cents (323101) | more than 10 years ago | (#8146714)

Very slowly? Staying in orbit is just like falling, but you "move out of the way of" the body (comet in this case) you want to orbit so you move next. Repeat this thought-experiment for the new position and so on.

typo correction.. (1)

Mr2cents (323101) | more than 10 years ago | (#8146731)

Very slowly? Staying in orbit is just like falling, but you "move out of the way of" the body (comet in this case) you want to orbit so you move next. Repeat this thought-experiment for the new position and so on.

It should of course read .. so you move next to it. My humble appoligies.

Re:Gravity? (5, Informative)

C17GMaster (727940) | more than 10 years ago | (#8146717)

From Rosetta's webpage [esa.int] : The relative speeds of the spacecraft and comet will gradually be reduced, slowing to 2 metres per second after about 90 days. If it moves slowly enough, the comet's weak gravity can hold it in.

Re:Gravity? (2, Informative)

mindriot (96208) | more than 10 years ago | (#8147501)

This is going to be a very difficult mission. I would love to have a job constructing the lander... I am simply amazed by the fact that we're able to hurl a piece of fragile technology at tiny objects in space that are far, far away (yes, considering how big space is, I would call Mars 'small' too) -- and they will actually get there in one piece and work.

I really hope they'll make it with this one. The German Max-Planck Institute for Aeronomy [linmpi.mpg.de] (soon to be called Institute for Solar System Research) is responsible for the lander. My mom works there, so from what she talked about I could tell how complicated the development of such a lander is.

Considering how long one of the computer scientists there has been working on the lander software, and what kinds of stress testing procedures the parts had to go through (some of them were done at Astrium in Munich [astrium-space.com] and my mom had the honor of personally delivering the components...), I have deep respect for the engineers who work on such projects - even more when they actually make it work (Spirit/Opportunity).

Also, I am glad that the Rosetta project got to keep going at all, considering that originally it was supposed to visit Wirtanen [linmpi.mpg.de] (German link, for English see maybe here [esa.int] ), a whole different comet. That also means that for the new target, the lander's software and some components even had to be redesigned to suit the new comet's features. So, good luck to Rosetta - hitting this target would be one cool achievement.

Oh, also, this ESA page [esa.int] has some nice information about the mission as well.

Re:Gravity? (0)

Anonymous Coward | more than 10 years ago | (#8147118)

The are going to use sexual attraction to keep it in orbit.

Business Plan (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8146623)

1. Study comets.
2. ???
3. Profit!!!

I hope the harpoon works... (5, Interesting)

bc90021 (43730) | more than 10 years ago | (#8146626)

...given that we probably know little about the surface of the comet.

Given that it could be porous (or even lots of shatterable ice), I hope that the harpoon has the force to bury itself deeply enough to actually anchor itself in something solid.

Jerry Bruckheimer (1)

AtariAmarok (451306) | more than 10 years ago | (#8146633)

given that we probably know little about the surface of the comet....Given that it could be porous (or even lots of shatterable ice)

If the world works according to Bruckheimer rules, the impact of a harpoon is likely to make the comet go up like the Death Star.

Probe's last words... (2, Funny)

Anonymous Coward | more than 10 years ago | (#8146744)

"Towards thee I roll, thou all-destroying but unconquering comet; to the last I grapple with thee; from hell's heart I stab at thee; for hate's sake I spit my last breath at thee. Sink all coffins and all hearses to one common pool! and since neither can be mine, let me then tow to pieces, while still chasing thee, though tied to thee, thou damned comet! Thus, I give up the spear!"

Re:I hope the harpoon works... (1)

DoraLives (622001) | more than 10 years ago | (#8146826)

I'm getting a strong feeling that (should the thing succeed to this point) immediately following receipt of telemetry that the harpoon has been fired, receipt of telemetry will cease.

Re:I hope the harpoon works... (0)

Anonymous Coward | more than 10 years ago | (#8146890)

you know, in the absence of any other forces in space, and applying a fundamental law: every action has an equal and opposite reaction, won't the space craft be sent flying the opposite direction of the harpoon?

Oh this is not important... why I even bother posting?

Re:I hope the harpoon works... (1)

Ulven (679148) | more than 10 years ago | (#8146954)

Small harpoon going 30cm === large (relativly) spacecraft going 3mm.

And of course, by the time it has moved it's been anchored.

Re:I hope the harpoon works... (0)

Anonymous Coward | more than 10 years ago | (#8147312)

Depends on the mass. When you fire a gun, do the bullet and gun go in the opposite directions at the same speed?

Got some doubt going here... (5, Insightful)

mobiux (118006) | more than 10 years ago | (#8146645)

I know that landing on Mars is a very tough thing, lots of variables to consider.

But this seems like it would be exponentially harder.
Ya know, landing on something that doesn't have gravity and they don't know what it's made of.

Re:Got some doubt going here... (5, Funny)

Darth23 (720385) | more than 10 years ago | (#8146655)

That's why they should use Duct Tape instead of a harpoon.

Re:Got some doubt going here... (0)

Anonymous Coward | more than 10 years ago | (#8146896)

During the orbiting phase, it should wrap a strip of velcro around the comet. It would have the corresponding piece of velcro on itself. You can't be sure that the surface will be suitable for either harpoon or duct tape, but you can count on velcro to stick to velcro.

Re:Got some doubt going here... (0)

Anonymous Coward | more than 10 years ago | (#8146913)

I had the same thought but using zip ties. Then I thought some more and realized that a lasso would probably be easiest.

Re:Got some doubt going here... (-1, Flamebait)

Anonymous Coward | more than 10 years ago | (#8146709)

We don't choose it beacuse it's easy. We choose it because it's hard. We're not Americunts.

Re:Got some doubt going here... (1)

cyclone1996 (666679) | more than 10 years ago | (#8147216)

It's certainly a significantly different kind of problem. You don't have to worry about parachutes and atmospheric entry but the orbital mechanics are extremely tricky due to the weak gravity field.

Fortunately, they do have some experience to draw upon. NASA's NEAR mission [jhuapl.edu] managed to land on a 21x8x8 mile asteroid named Eros and operated afterwards, despite the fact it was not actually designed to land. Performing that end of mission "stunt" contributed greatly to the overall knowledge of operating around small bodies, although the comet will be even less massive and more challenging.

Saves on fuel? (1)

Anonymous Coward | more than 10 years ago | (#8146647)

Maybe this is a good way for humans to travel thru space while conserving fuel. Comments?

Anyone good with gravity? (4, Interesting)

questamor (653018) | more than 10 years ago | (#8146657)

I'm curious. How big does an object have to be to have gravity that'll hold say, a person to it?

I'm thinking say, if I were standing on a rock the size of NYC out in space, would I just drift away from its surface without any noticeable gravity, or could it hold me there? How about something the size of a state like Oregon? or something only 2miles in diameter?

Re:Anyone good with gravity? (0)

Moderator (189749) | more than 10 years ago | (#8146690)

I'm totally speculating here (and someone correct me if I'm wrong), but I think that in a vaccum, without the interference of any other bodies, you *and* the object, no matter how big it is, would be pulled towards each other. The distance you travel vs. the distance the other object travels is proportional to your mass vs. the mass of the object. I don't think an object has to be *any* size to hold you there; eventually, you will be attracted to each other.

Re:Anyone good with gravity? (3, Informative)

Anonymous Coward | more than 10 years ago | (#8146847)

As far as we know, every object "pulls" on every other object. However, if you're moving away from an object at a sufficient speed (escape velocity) then its pull will never reverse your motion.

For a small object, escape velocity can be quite small. Take a spherical comet 1 mile in diameter. This is about 1/4000th that of Earth. Suppose it has the same density as our planet (surely an overestimate). Then its gravity would be about 6.4e10 times weaker.

More importantly, as you stand on the surface, your potential energy would be 1.6e7 times smaller than it is on Earth's surface. To achieve escape velocity (at the surface), a spacecraft's kinetic energy must be larger than its potential energy. So escape velocity on the comet is 4e3 times larger than on Earth. Escape velocity on earth is about 11.18 km/s, so on the comet it is only about 2.8 m/s.

So if you try to make a soft landing on the comet, and with your initial bounce you are moving away from the comet at 2.8 m/s (i.e. 6.3 miles per hour), then you will need to make some corrective measure, or else you will just fly away from the comet and never return.

Re:Anyone good with gravity? (3, Informative)

halftrack (454203) | more than 10 years ago | (#8146750)

It's all about escape velocity. [wikipedia.org] The mass needed to keep a person on an object or in an orbit comes down to the speed the person can obtain by its own force. (Jumping or pushing or something.) Since an object like this is evacuated there is little to slow things down so should the get a little push in a direction, it will have a relatively large impact.

(And no, I don't care to do the math.)

Ok, here's the math (5, Informative)

rillian (12328) | more than 10 years ago | (#8147070)

As mentioned, you have to be moving slower than the escape velocity [wikipedia.org] to be in orbit around something. The formula is v = sqrt(2GM/r). G is 6.67x10^-11 m^3/s^2kg everywhere.

For Earth, M is 6x10^24 kg, and the highest relevent velocity as at the surface, so r = 6x10^6 m. That's 11.2 km/s. Very fast. Which is why it's hard just to get into orbit.

Now for the comet. If it's 4 km across, r = 2000 m. I can't find a value for the mass, but based on the common description of comets as dirty snowballs [seds.org] let's guess the density is about that of water, or 1000 kg/m^3. The volume of a sphere is 4/3 r^3 so our guess for M is 3.35x10^13 kg.

That makes the escape velocity for 67P/Churyumov-Gerasimenko at 1.5 m/s which pretty much the same brisk walking-speed which which the lander is expected to hit the comet, especially if our guess at the density is high. Thus, the lander could easily bounce off, and a person could with some effort jump off, fast enough that the comet's gravity wouldn't bring them back. On the other hand, an rocky asteroid (denser) the size of Manhattan (bigger) would probably be hard to get away from under your own power. This comet is right on the edge.

Re:Anyone good with gravity? (4, Informative)

kryptkpr (180196) | more than 10 years ago | (#8146761)

Fg = G*m1*m2/d^2

with m1 your mass, m2 the rock's mass, G being 6.67e-11 for our universe and d being the distance between you and the rock.

So there is ALWAYS gravity, but when you hit an asteroid at 1m/s, your momentums (m1*v1) and the asteroid's momentum (m2*v2) adjust, and propel you and the asteroid in opposite directions because momentum, like energy and forces, is conserved.. and since m2 >> m1, this results in a bouncing off situation (there's a formula for it, but I can't be bothered to break out the notes from first year physics).. The gravitation force between you and the asteroid now has to be enough to counteract this bouncing-off-one-another for you to stay on it.

Re:Anyone good with gravity? (1)

Krunch (704330) | more than 10 years ago | (#8146797)

If there is no lost energy ("perfect" bounce), m1*v1+m2*v2 = m1'*v1'+m2'*v2'
With mX' and vX' the mass and speed after the impact.

Re:Anyone good with gravity? (1)

halftrack (454203) | more than 10 years ago | (#8146897)

I'm sorry but the formula you introdused only states that momentum is preserved, not energy. Also your formula true for all collisions, 'perfect' or not, also when kinetic energy isn't preserved. The grandfather is however only vaguely on target when addressing the question of staying inside the gravitational field of a comet. The thing to address is energy, not momentum.

Re:Anyone good with gravity? (1)

Krunch (704330) | more than 10 years ago | (#8147342)

You are right. And momentum has not much to do with escape speed. If I remember well, escape speed can be calculated from the enery needed to gain infinite potential energy from the planet/comet or something. G*M*m/d=(mv^2)/2 => v=(2*G*M/d)^(1/2) with G the gravitational constant, M the mass of the planet/comet and d its radius (yes it's a spherical bear :op ). Now from the article, the comet's diameter is 4km and assuming it's mainly water its density should be around 1kg/dm^3. Volume of a sphere is (4*pi*r^3)/3 thus escape speed is (2*G*((4*pi*(2*10^3)^3)/3)*10^3)/(2*10^3) ~ 1.5 m/s according to bc. But I probably did a mistake somewhere anyway.

Re:Anyone good with gravity? (1, Informative)

Anonymous Coward | more than 10 years ago | (#8147196)

Here's the way you'd go about calculating the orbital velocity. This is a Newtonian (in the very essence of the term) question, and can be solved using only forces. The key relation is that for a particle moving in a circular path, the force required to keep it moving in that path is

F = m v*v / r

Where m is the object's mass, v is its velocity, and r is its radius. Newton's law of gravitation states that the force exerted upon a mass by another mass is

F = G m M / r*r

G being the gravitational constant, m and M the objects respective masses, and r their seperation. We'll assume that M >> m, so it can be regarded as having no acceleration. We can then set these equal, and find

v * v/R = G M / R*R ...
v = SqrRoot(G M / R)

Looking at the article, we see that r = 2 km = 2x10^3 m. We can do a seat of the pants calculation of M by assuming that the comet is solid and made of water (1g/cm^3 = 1000 kg/m^3)

M = density*V = (1000) (4/3 pi r^3)
= 3*10^13 kg

So, finally, using G = 6.67*10^-11 and R=3 km (this is the orbital radius), we have v = 0.3 m/s, or about one mile per hour.

Re:Anyone good with gravity? (1)

UtSupra (16971) | more than 10 years ago | (#8146833)

Any two bodies attract and that force is proportional to the inverse of distance squared (and proportional to the product of the masses). A small distance (between the centers of mass of the bodies) implies a huge force. The question is not whether there is enough gravity to hold the object, but what other forces are involved.

Re:Anyone good with gravity? (1)

I don't want to spen (638810) | more than 10 years ago | (#8146887)

Its to do with mass and not physical size. The object doesn't have to be big at all - a black hole is a singularity and effectively has no size. Okay, so its event horizon does (this is to do with the distance from the black hole that the escape velocity - how fast you need to move to escape the gravitational pull - exceeds the speed of light).

A small dense body could have more gravitational pull than a larger, less dense one. Comets are not very dense or large, so have a small gravitational pull.

Re:Anyone good with gravity? (0)

Anonymous Coward | more than 10 years ago | (#8147290)

Actually it has everything to do with physical size and density as far as talking about orbits close to the object and escape velocity from an objects surface. The reason? Orbits are assumed to be outside the surface of the object. Escape velocity is a factor only when talking about going beyond the surface of an object. Given equal mass, the gravity force immediately outside of the surface of a less dense but larger object will be smaller compared with the gravity force immediately outside of the surface of a more dense but smaller object.

If you are at or beyond the surface of the larger objects, then the force of gravity is identical and only depends on the mass of the objects (which is the same).

Re:Anyone good with gravity? (0)

Anonymous Coward | more than 10 years ago | (#8147024)

Pretty big I think because even the moon could have astronauts jumping high enough to go into orbit and maybe even leaving it's gravity completely. I think you'd be safe with something the size of the earth down to the size of the moon (one third of the earth?) but anything smaller you might be in danger of jumping too high if you got a job promotion :> and then disappearing literally "off the face of the earth"!.

Phobos and Deimos would be dangerous to walk on for example

Harpoons? (0)

Anonymous Coward | more than 10 years ago | (#8146661)

We're whalers on the moon.
We carry our harpoons,
but there ain't no whales
so we tell tall tales
and sing this whaling tune.

Re:Harpoons? (0)

Anonymous Coward | more than 10 years ago | (#8146710)

I'm going to go start my on comet with blackjack...and hookers! Ah, forget about the comet...and the blackjack.

HAIKU! (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8146675)

Micheal takes off shirt Taco unzippers pants Micheal blows Taco

Re:HAIKU! (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8146712)

Taco drops the soap
he bends down to pick it up
bye-bye ass cherry!

I have doubts (4, Funny)

Rosco P. Coltrane (209368) | more than 10 years ago | (#8146684)

And it will take up to 2014 before landing on Comet 67P/Churyumov-Gerasimenko -- with the help of a harpoon.

What makes them think they'll be able to land an unmanned probe on a small rock in deep space that way when here on earth, countless bigger, manned ships have tried the same feat on whales for decades and failed?

They're just gonna kill that poor little comet. For nothing. Just like that. Somebody calls green-piss ferchrissake!

Re:I have doubts (1)

psi42 (747491) | more than 10 years ago | (#8146827)

"They're just gonna kill that poor little comet. For nothing. Just like that."


They're not just going to kill it! They're going to study it, torture it, bombard it with microwaves, dig holes in it, and "make an on-the-spot analysis of the composition and structure of the comet's surface and subsurface material" while it's still alive! Now the question is, who do we call about this?

Re:I have doubts (1)

multipartmixed (163409) | more than 10 years ago | (#8147148)

Not to put too fine a point on it, but are you not aware that we harpooned the Humpback Whales complete ly out of existance? And nearly did it again, hitting a Bird of Prey with one of those suckers?

Yeesh.

Low success rate... (-1, Troll)

syzme (584270) | more than 10 years ago | (#8146695)

Lets just hope for the ESAs' sake that its easier to land on an comet than it is to land on Mars [google.com] .

Re:Low success rate... (0)

Anonymous Coward | more than 10 years ago | (#8146726)

Since there's not much gravity there, it should be. Even though I wonder how rugged the surface will be and how they will determine a landing spot. I think an American probe has already successfully landed on an asteroid, even though it wasn't part of the mission plan. It didn't do much when it landed. I think they did it just to see if they could.

Hope the ESA does matter this time (5, Interesting)

fname (199759) | more than 10 years ago | (#8146701)

The French had a very reliable launch vehicle, the Arianne IV, which they decided to "upgrade" with the Arianne V. After failing on 4 of the first 13 missions, they introduced an upgraded version with an extended nozzle. The failure of that launch led to the (highly justified) delay of the Rosetta launch on a similar Arianne V because of the failure investigation. Turns out that the nozzle had a design flaw which led to the failure.

ESA did pretty well on their 1st trip to Mars, as the Mars Express is an unqualified success, but the Beagle II didn't work for whatever reason. All this is just to reiterate that space is hard, and there will be successes and failures. No one's at 100% (Russians have a worse track record on Mars than anyone, and NASA lost Contour--not a JPL mission-- last year due to an obvious design flaw).

Whenever a new technique is tried in space for the 1st time, the odds increase. That Pathfinder worked on its first attempt at a bouncy landing, and Sojourner roved Mars without a hitch speaks to the talent & luck of the JPL crew. Hopefully the Europeans will do as well with their harpoon, and hopefully they haven't made obvious mistakes like those made by NASA and the APL did in the Contour comet mission.

French spaceship? Silly english pigdogs. (-1, Flamebait)

Anonymous Coward | more than 10 years ago | (#8146720)

...The French had a very reliable launch vehicle, the Arianne IV, which they decided to "upgrade"...

Problem is, since it is French, it tends to run in terror from comets and other celestial objects. Not only that, it was recently revealed that the Grand Vagnuh of Saturn has been bribing the French government with dilithium.

Re:Hope the ESA ... slightly OT (1)

dddno (743682) | more than 10 years ago | (#8146849)

I'm not sure if you deliberately write it as you pronounce it, but in case you don't: it's "Ariane", not "Arianne". If that is a typo, it's a frequent one. And Ariane is clearly not french. There is substantial french contribution, no doubt -above all the launch site- but Ariane is a European project. I agree with you that Ariane 4 was abandoned with too great a haste- however, that step was inevitable sooner or later. Ariane 5, plus extensions, will be able to carry much larger payloads, and for smaller launches the Vega will take over for Ariane 4.

Re:Hope the ESA does matter this time (1)

Fat Cow (13247) | more than 10 years ago | (#8147130)

I was surprised to see you say refer to a NASA mission as non-JPL. What do you mean by this? Isn't JPL is a part of NASA? Also, what about this [nasa.gov]

Re:Hope the ESA does matter this time (1)

fname (199759) | more than 10 years ago | (#8147332)

Well, all these aerospace programs have a lot of hands in them. It wasn't a JPL mission in the sense that JPL was not in charge of the system engineering, and they were not in charge of overall mission success-- they had a team that contributed to one part of the mission. The failure of Contour wasn't due to the failure of any one system, but instead was likely due to a component working as designed, but the system engineers did not understand how it would function; working as designed the solid rocket motor fired to kick Contour out of orbit likely damaged other parts of the craft and led to its failure. Read more here [spacedaily.com] .

JPL is actually a federally-funded research & development center (FFRDC), run by Caltech. Most of JPL's funding does come from NASA, but JPL employees are not NASA employees. If you don't believe me, just ask one!

Re:Hope the ESA does matter this time (0)

Anonymous Coward | more than 10 years ago | (#8147472)

There is no way in hell this mission will succeed. You can read the writing on the wall. It's too complex.

First it has to get into space which is somewhat unlikely given the French track record.

Then it's going to travel for 10 years. The more time out there is more time for things to go wrong. This part of the mission probably isn't so bad though.

Then it has to orbit for months. I find it highly unlikely it will go into orbit correctly. But you never know...

Then it has to launch the lander. Oh boy, this is where things get hairy. So many things could go wrong here.

Then the lander has to land correctly. Yeah... sure.

Then the lander has to launch a harpoon into the planet... yeah...

So much complexity... Egads... There is just no way this is going to work. Write it off now.

Off Topic: Aarrrggg! (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8146801)

I hate the way the &@^% mouse wheel interacts with the moderator pull downs. If you forget to click outside the widget, there goes your moderation!!

Re:Off Topic: Aarrrggg! (0)

Anonymous Coward | more than 10 years ago | (#8146831)

I hate the way the &@^% mouse wheel interacts with the moderator pull downs....

Stop using I.E.

Arrgh! Thar she blows, The White Comet.... (3, Funny)

Graemee (524726) | more than 10 years ago | (#8146811)

Too bad they didn't call the craft Ishmael or Ahab.

Long Now Foundation (-1, Offtopic)

E.S Taog (594473) | more than 10 years ago | (#8146852)

The Rosetta project is part of the Long Now [longnow.org] Foundation's mission to document as many different languages as possible. It's thought that 50 - 90% of the world's languages could die out by the next century, and this project is hoped to highlight the importance of saving native languages.

While I certainly appreciate the Long Now's aims, I think there is probably a cheaper way of publicising this issue. Money that could be ploughed into encouraging indigenous societies to use their own languages, or to document them properly. Also, why the bible for fuck's sake? Just imagine, if (and this is a big if) some alien cunts were able to decipher one of the languages on the disk, and then had the dubious joy of reading the first three chapters of Genesis. If they manage to stay awake they will certainly conceive of some very strange notions about us.

I'm sure they will wonder how we created space flight when we appear to believe that some Deity created the world in seven days. Or turn up asking us who this God dude is, and can they commission him to create some more worlds. They'd have been better off using some other work or fiction or mythology.

AVAST! (-1, Redundant)

Anonymous Coward | more than 10 years ago | (#8146862)

Argh, I'll be needing one rocket, a few gravity wells, a harpoon, and a stout ship to breach the beast and bring me home her precious precious booty! Space faring bacteria HOOOOOOOOO!

-rt

Corset hunter? (1, Funny)

Anonymous Coward | more than 10 years ago | (#8146922)

I initially read this a corset hunter, which piqued my interest.

Then I remembered I was on Slashdot. News for nerds. Since I'm married, I claim that I'm no longer a nerd, just a plain old geek.

Dangerous route (2, Insightful)

Limburgher (523006) | more than 10 years ago | (#8146923)

I'm just hoping Rosetta survives the trip. I can just picture it getting Beagle-2'd by an asteroid on one of it's 2 trips through the asteroid belt. I mean, I know it's a longshot, but you never know. I hope ESA's luck improves with this one. Thie could be realy cool.

Re:Dangerous route (2, Insightful)

snake_dad (311844) | more than 10 years ago | (#8147214)

It sounds like you think that ESA has trouble putting together a succesful mission based on the fact that Beagle2 seems to have failed (maybe I'm wrong, but that's the impression that I got from your post)...

First, Beagle2 was not an ESA project, but that's nitpicking... Second, the "main" part of the European Mars mission, the Mars Express [esa.int] , is working flawlessly thusfar, with spectacular imagery sent back already.

And, there have been many more succesful ESA missions. There have been many more ESA missions [esa.int] (click the Science Missions dropdown box). Remember the Giotto mission to the comet Halley, Smart-1 now flying to the Moon using an ion engine, Cluster examining the solar wind, Integral doing X-ray research, Ulysses examining the solar system from outside the ecliptic, and the commercially succesful Ariane launcher.

I'm in no way trying to start a flame war on who has the best space agency judging on missions (IMHO NASA would win that one hands down anytime), it just irks me that one probably failed mission-part affects the public opinion about the European space efforts so much.

Kill it (2, Funny)

mnmn (145599) | more than 10 years ago | (#8146924)

So after the lander fires a harpoon, the rigid comet breaks into hundereds of pieces and a single "oops" by mission control will echo around the Houston room.

Whats wrong with superglue? Still stuck with the "lets go GET it" thinking?

Rants aside. I really hope it works, and we get high res public domain pictures of it to make our desktop wallpapers out of.

I wonder if it would be cheap enough to steer the whole comet towards the earth into an orbit, and just bring it right next to the IIS. Spacewalking astronauts could then harpoon it to their hearts content

Re:Kill it (1)

Sinus0idal (546109) | more than 10 years ago | (#8146959)

This is an ESA mission. Why would it echo around the Houston room?

Re:Kill it (0)

Anonymous Coward | more than 10 years ago | (#8147046)

Maybe he really meant a Nelson style "Ha ha!" will echo in Houston.

This sounds familiar (0)

Anonymous Coward | more than 10 years ago | (#8146956)

Over the building, through the window, around the telephone pole, off the wall, around Saturn, through the asteroid belt, near Mars, between Earth and the Sun, nothing but net. Err.. harpoon.

Deep Space Project (0)

Anonymous Coward | more than 10 years ago | (#8147001)

Whatever happened to NASAs "Deep Space" project. Y'know the craft with the ion acceleration engine? IIRC Deep Space IV was supposed to attempt a comet landing but I'm reaching back to about 1998 here. Was this scrapped? I know that DS I was considered a success.

Re:Deep Space Project (0)

Anonymous Coward | more than 10 years ago | (#8147160)

It went up Bob Goatse's ass and has never been heard from since

Equal and opposite reaction? (2, Interesting)

aiken_d (127097) | more than 10 years ago | (#8147037)

In the absence of significant gravity, won't a significant amount of the force used to launch the harpoon serve to actually propel Rosetta *away* from the asteroid? Can someone explain what's to keep the harpoon from going "boink" against the comet and Rosetta from not just bouncing but actually being propelled into space by the harpoon launch?

Cheers
-b

F=MA (1)

FlyingOrca (747207) | more than 10 years ago | (#8147443)

Presumably the harpoon will have waaay lower mass than the lander, and the comet waaaay higher mass than either. Low acceleration for the lander = no problem in the time scale we're talking about. High mass (approaches 0 accel.) for the comet means that the harpoon buries itself. I think...

Prospecting vs exploring (5, Interesting)

Uncle Barnard's Star (714324) | more than 10 years ago | (#8147111)

The cool factor is undoubtedly high, kind of like catching a speeding racing car to find out what's under the hood. The risks are high, and the payoff is worth its weight in journal articles. Maybe it's time for missions that try to justify thier cost in kind.

The so-called great voyages of discovery of the past were never undertaken for the sake of idle science all. Always there was that search for the elusive El Dorado or that secret shortcut to the spice capital of the world. While most voyages failed to recoup the wood and slave labor invested on them, enough returned with if not the silver and gold then things that would prove more valuable, like coffee, cannabis or the claims to a "New" World.

The pure science mission ("Is there life on Mars?") is a modern invention. While the altruism is admirable, the only way to justify to taxpayers the continued exploration of space is to turn these missions into hunts for precious metals and minerals. Follow not just the water (a valuable space resource in its own right) but also the platinum.

BOB GOATSE MARTYRS BRIGADE (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8147138)

Has successfully landed on the Christmas Islands and is now in the process of extracting vengeance.

ALL HAIL GNAA!

ALL HAIL SEXUAL ASSPUSSY!

ALL HAIL BOB GOATSE!

What is Rob Malda doing with my shit in his mouth?

There she blows! (1)

criordan (733016) | more than 10 years ago | (#8147466)

"Towards thee I roll, thou all-destroying but unconquering whale; to the last I grapple with thee; from hell's heart I stab at thee; for hate's sake, I spit my last breath at thee. Sink all coffins and hearses to one common pool! and since neither can be mine, let me then tow to pieces, while still chasing thee, though tied to thee, thou damned whale! Thus, I give up the spear!"

Decade long hunt... Harpoons... Big ass prey...

I think I've heard this story before
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