Exploring the universe (why don't we try this?)

SkyHog

SkyHog

Touchdown! Greaser!
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Everything Offends Me
There's a big ol' comet coming in 2013. It appears that it is going to fling itself past the sun and then eject from our solar system.

Why don't we try to find a way to stash some sort of monitoring device....transmitter, or something, on it. Maybe even a camera. Let it take us for a ride.

That would be awesome, and I bet we could learn a lot without having to expend too much fuel to do (aside from actually getting to the comet).

2 questions:
1. Has this ever been discussed before?
2. Any SciFi use this idea?
 
By the way, I thought about the idea of "Well, if you're going that fast anyway, you don't need the comet."

I'm thinking we find a way to approach it from the other side. I don't believe we have the capability to travel as fast as a comet travels. Instead, we get in front of it and travel slow enough that we "crash" into it, lightly (or something). Something survivable for the equipment. Boom - instantly, we're going fast.
 
Umm, no.

It would take just as much fuel to rendezvous with the comet as it would to fly the same trajectory on our own. You gain nothing but a big iceball in your way and a lot of extra failure modes. Besides, if you fly your own trajectory, you can pick where it goes.

And there is no such thing as a survivable orbital speed crash. I think you underestimate just how fast that is.

You can play orbital games with third bodies, but they need to be a lot bigger than a comet. The effect is significant -- it makes the difference between feasible and not feasible in several cases -- but it's not nearly as large as you're hoping for. The Voyager spacecraft did some of that with most of the major planets (the second body is the sun, the first is the spacecraft).
 
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Well...

Halley's Comet travels at a speed of 157,838 (on average, I presume). If we can launch, gather speed by orbiting a nearby body (Mars, Moon, Venus, or something), I wonder if we can gain enough speed to cause a "surivivable" crash. Maybe by getting in front and approaching at an angle.

Just a thought...
 
If you can get enough speed to make a "survivable" crash, you can make enough speed to go out on your own. Orbital speeds are enormous.
 
Once you are settled on the comet how would you keep the dish antenna oriented to earth or the sensors array on a tumbling rock.

José
 
I don't believe we have the capability to travel as fast as a comet travels.
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Deep Impact and Stardust have already done comet research.
The Pioneer, Voyager and New Horizons spacecraft are outrunning anything in the solar system that is not above solar escape velocity...which is for all practical purposes everything.
 
SkyHog said:
By the way, I thought about the idea of "Well, if you're going that fast anyway, you don't need the comet."

I'm thinking we find a way to approach it from the other side. I don't believe we have the capability to travel as fast as a comet travels. Instead, we get in front of it and travel slow enough that we "crash" into it, lightly (or something). Something survivable for the equipment. Boom - instantly, we're going fast.
Click to expand...

You're driving a small car, just entering the highway. You don't want to use the fuel (or don't have an engine capable of going highway speeds) so you decide to let an approaching 18 wheeler catch you from behind. See the problem with this scenario? :)

In order for the comet to not vaporize your probe you'd have to accelerate to match its speed... thus defeating the whole purpose. It would only be worthwhile if the comet had its own propulsion system and gave you an extra boost. But in reality your probe and the comet are subject to the same laws of gravity and orbital mechanics.
 
Wouldn't the outgassing from the comet obscure most of the view from the thing? The vapor it emits is what makes it visible to us, after all, and that vapor is a fairly large shield around it.

Dan
 
dukeblue219 said:
You're driving a small car, just entering the highway. You don't want to use the fuel (or don't have an engine capable of going highway speeds) so you decide to let an approaching 18 wheeler catch you from behind. See the problem with this scenario? :)

In order for the comet to not vaporize your probe you'd have to accelerate to match its speed... thus defeating the whole purpose. It would only be worthwhile if the comet had its own propulsion system and gave you an extra boost. But in reality your probe and the comet are subject to the same laws of gravity and orbital mechanics.
Click to expand...

I think, using the car analogy, if I entered the freeway driving 65, and a truck rear ended me at 75, that it would not be a catastrophe, especially if I made the car strong to withstand the impact. I don't know if we could achieve the same sort of ratio with a comet though.

Additionally, I am pretty sure that if you caught a semi in the same situation, but at an angle that slowed the closure rate even more, it would be even less of an impact, right? Rather than 90 degrees or 180 degrees?
 
I think, using the car analogy, if I entered the freeway driving 65, and a truck rear ended me at 75, that it would not be a catastrophe, especially if I made the car strong to withstand the impact.
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It's more like a moped at 65 and being rear ended by a 75mph freight train. Once it hits you, it knocks you down and runs you over and with any luck, you can hold onto one of the freight car axles to hitch a ride.

To not damage your spacecraft, you'll need impact velocities in the 5-10mph range and in the same direction. If you've put that much energy into the vehicle, you're already at the comet speeds. And you don't have to worry about the landing breaking your antenna off, or rolling over upside down, or the surface swallowing you, or outgassing/tidal effects mangling/burying the spacecraft. You're also faced with extremely low gravity and if it's spinning, you'll probably need something to stake the spacecraft down with.

Comet research, sure. Land on the thing just like landing on an asteroid or Mars. Just to hitch a ride, it's probably more practical to do free flight.
 
The only way hitching a ride would be worth doing is if we could get it to stop first so that we could land on it.
 
Guys this actually isn't that hard to do. I watched Bruce Willis do it for christ sake.
 
RedFirstGen said:
Guys this actually isn't that hard to do. I watched Bruce Willis do it for christ sake.
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Yes, and now you can watch him time travel and try to kill himself when he was younger. Paradoxes like that really strain the suspension of disbelief....
 
go pros are shock proof, it can take it
 
From what I understand about these comets, limited as it may be, is the speed is fastest when it's hooking around the Sun. So in your scenario we would be trying to match speeds when it's at or very near its fastest...us being third rock from the Sun and all.
 
There actually has been an asteroid rendezvous, an utterly amazing bit of science. I can't honestly see the advantage to tacking a probe on a comet. Voyager is already on it's way out of the solar system, another amazing piece of NASA hardware.
 
steingar said:
Voyager is already on it's way out of the solar system, another amazing piece of NASA hardware.
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Didn't the Enterprise find that and then stopped it from destroying the universe? Didn't Spock do a mind meld with it too?



:)
 
Just getting some hunk of metal from Earth to escape the solar system's gravity isn't all that difficult or expensive (by space mission standards, I mean). Building a hunk of metal that can operate successfully in the interplanetary environment for the years it takes to get out there, make whatever measurements or observations you want, and communicate with us back here on Earth, that's the really hard part.
 
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