Let's land on the Sun.

[Artlav]

For whatever not-so-sane reason our objective would be to land an unmanned spacecraft on the Sun to send back data and pictures.

How could that be done?

The surface area is pretty hot, are there any solid materials that can stand the heat and have enough insulation to keep insides cool for a long enough while? Some kind of ceramics is the only thing i can think of.

There is no solid surface, so some kind of balloon should be used to keep the thing in one place. Considering the heat and implausibility of ceramic balloons, the ship itself should be capable of displacing enough stuff (hydrogen?) to stay afloat.

A powerful power source should be on board, for refrigeration an probably to counter intense magnetic fields and EM noise that should be found there.

How would it send data back? Taking off from the Sun is unthinkable.
Can anything be detected on it's background?
I there any silent EM band in Solar noise?

But before all that the ship have to get there.
What about the corona? Is it's density low enough to be disregarded?

With ~30g's of surface gravity the ship would be going at around 500 km/s nearing the surface.
Can anything be used to slow it down?

What about instrumentation? What kind of devices capable of returning interesting data could survive there?
Finally, what kind of data could be worth all the trouble?


What do you think?

 

[N_Molson]

I'd say that, if you survive the heat, radiation pressure could significantly slow you down at some point...

 

[Ghostrider]

Well, you could land at night...

 

[Artlav]

I'd say that, if you survive the heat, radiation pressure could significantly slow you down at some point...

Interesting. What about a landing with a huge solar sail? A kind of parachuting down.
Once again a problem of a heat-resistant enough foil.

Well, you could land at night...

Impressive.
I totally expected this to be in the first comment.

 

[N_Molson]

Well, then the "umbrella" configuration seems obvious... Under the umbrella a huge tube containing mostly refrigeration loops, and as many radiators as possible...

That would be ok for the "approach", but once in the heliosphere, that's another problem, since hot matter would render the radiators inefficient and eventually burn them down. Maybe it could drop some kind of "lander" from there and relay communications to Earth ?

 

[Ghostrider]

Well... On a more serious note I remember that when I was young (and my heart was an open book et cetera) I did think that a photograph of the Sun's inside would be totally cool (in a non-temperature-y way).

The "solid" surface of the sun is well down into its depths so it's not exactly like landing, more like going on an immersion into it. Temperature and radiation are going to be a BIG issue there so you're going to need some sort of EM shielding to keep the nasty rads and plasma out. As for the heat... Do we have some stuff that vaporizes or sublimate at those temperatures that we can then eject along with the heat? It's not going to last long of course...

 

[tori]

I'd go with an extra big-a## ablative shield made out of some kind of an insulating material (let it ablate, but don't let it let the heat in too fast). The entire ground operation would be a matter of dozens of seconds - take some snaps, broadcast them, plant a flag, and fizzle out.

Edit re: broadcasting: extremely low frequency RF? That could work.

The Real World introducer [on TV]: This week on The Real World: the Sun.
Man on Sun [on TV]: [screams] I'm burning to death!
Leela: [sighs] You know how much an apartment that big would cost on the Sun?
(from Futurama)

 

[Stevodoran]

and it would give you a whole lot of power

 

[JackJL]

What if you put a honking great electromagnet on the ship? (or charged the ship - Is the sun as a whole charged?) This might be able to levitate it for braking and/or deflect the plasma so that the only heating would be radiative.

What about instrumentation? What kind of devices capable of returning interesting data could survive there?
Finally, what kind of data could be worth all the trouble?

If this is a huge ship, you could bring a neutrino detector. Get some direct evidence that flavour oscillation causes the solar neutrino problem

 

[Hartmann]

It could be very difficult because is an extreme enviroment :hotcool:

But It could be like Icarus spacecraft from the Solaris movie, a giant reflective shield and a probe made from ceramics , aerogel , or other resistant material that can descent to the surface.

The problems could be plasma flow, radiation, heat from particles, and magnetic fields .

 

[T.Neo]

You cannot land on the Sun, it doesn't have what one could conventionally regard as a "solid surface". It's also very hot, so hot that no conventional material could withstand it.

If the actual plasma could be kept at bay with a magnetic field, perhaps then the radiation could be reflected (unless you had some sort of perfect reflector, which is either handwavium or unobtanium). If you had something considerably hotter than the surroundings (some sort of fancy powerplant) you could potentially cool the interior of the device long enough for it to return some useful data.

It might be useful to make the workings of the device out of stuff that can survive at extremely high temperatures, just so they require a tiny little bit less cooling/reflecting/shielding.

Of course if you could build the thing out of unobtanium, it could be sent into the star and come out the other side intact, if at thousands of degrees...

 

[fireballs619]

There was actually a Bradbury short story about this, where there is an expedition to take a hunk of plasma back to earth. I'll try to find the name.

Anyway, if you were meaning to return samples to the earth, how would you escape the suns gravity. You would have to essentially 'take off' from the sun.

EDIT: The story is called 'The Golden Apples of the Sun'. It's Bradbury, so he doesn't really get to into the science, but it still makes for an interesting read. I would highly recommend it to anyone. It is only 7 pages long, so you needn't have a lot of time to read it.

 

[Solar424]

In order to slow down the craft (or at least make it accelerate slower) you could use a solar sail.

 

[Kyle]

The surface area is pretty hot, are there any solid materials that can stand the heat and have enough insulation to keep insides cool for a long enough while? Some kind of ceramics is the only thing i can think of.

The tiles on the space shuttle can withstand a little of that kind of heat on re-entry, we could start there.

There is no solid surface, so some kind of balloon should be used to keep the thing in one place. Considering the heat and implausibility of ceramic balloons, the ship itself should be capable of displacing enough stuff (hydrogen?) to stay afloat.

I would imagine if such a mission ever happened, the spacecraft wouldn't land rather hover very close to the surface.

A powerful power source should be on board, for refrigeration an probably to counter intense magnetic fields and EM noise that should be found there.

Nuclear energy?? I have no idea.

How would it send data back? Taking off from the Sun is unthinkable.
Can anything be detected on it's background?
I there any silent EM band in Solar noise?

Well you 'could' have several spacecraft to bounce the signal. Like one in very low orbit around the sun, another a little inside the orbit of Mercury then send that signal towards Earth.

But before all that the ship have to get there.
What about the corona? Is it's density low enough to be disregarded?

Not sure.

With ~30g's of surface gravity the ship would be going at around 500 km/s nearing the surface.
Can anything be used to slow it down?

Solar Sail and Ion propulsion possibly.

What about instrumentation? What kind of devices capable of returning interesting data could survive there?
Finally, what kind of data could be worth all the trouble?

Maybe something similar to some of the sensors on the exterior of the space shuttle. For example this is from STS-28 during re-entry.

 

[anemazoso]

I don't think any current tech or any tech within reach would do the trick. You would have to use something like an expanded sheet of space-time flaw like Xeelee constructin material.

Or something that uses the suns energy to strengthen itself. Use the suns forces against it. Problem is, I have know idea what that would be.

 

[River Crab]

Although it's not landing, people have been leaning towards this, so I'll just right out and say it:
Rather than landing it, you could send a solar radiation-powered vessel towards the surface, where it would cease to be a solar orbiting satellite, and become a radiation-powered solar statite. Basically, like your Shukra station on Venus, but with radiation rather than buoyancy. Not sure if it's possible to have something that is light, heat-resistant, and reflective enough. But it's more plausible than a landing, for sure. :lol:

 

[jedidia]

I'd suggest metaphasic shielding :lol:

back to serious:

A powerful power source should be on board, for refrigeration

I don't think a powerful energy source would be much use for refrigeration. I mean, you can only get as much heat out of the craft as you can radiate. That means big radiators. On the other hand, the radiators have to be shielded on the sun-side, so big radiators mean a big shield. However, the bigger the surface of the shield, the more heat it will accumulate, which you also have to get rid of. So you need bigger radiators, and... oh well, you get the point.
I think it's absolutely clear that the winner in such an arms race can only be the sun, unless your probe outgrows it in radative capability. Since the Sun is almost a perfect black body, the only possible way for the probe to do so would be having a larger surface area... :blink:

So, as far as heat shielding is concerned, you'd be pretty much set for a magical device. Anything that needs to get rid of its heat is at a loss, because it can't possibly radiate more heat away than the sun can throw at it. Such are, I'm afraid, the laws of thermodynamics, at least if my limited mind wrapped itself around them correctly.

Edit: It should be possible to have a long radiator perpendicular to a heat shield, thus the surface area of the radiator can be magnitudes larger than that of the shield. I don't know how close in you could get with such a configuration before it starts picking up heat on the unshielded sides, though.

 

[RisingFury]

I doubt it's possible.

First, if you wanna float in there like a balloon, your balloon is gonna have to be vacuum and held together by the extreme strength of the balloon itself. The reason for that is that if you fill the balloon with equal pressure and temperature hydrogen... well, then it'd be like filling up a balloon with Air on Earth and expecting it to float.


Second, your cooling is gonna be a major problem... like... big time...
Not only do you need immense power generation to do that, whatever cooling gas you use will have to be heated inside the ship to HIGHER temperature then the surface of the Sun, so that the heat actually flows out...


There's no known material that would stay solid at those temperatures, which means that your heat exchangers would melt...


Your power source would have to be a power store. Any heat engine would produce more heat then power, so no way of pumping it out...


My best bet would be to just create a probe, then encase it in a very very thick shield that would take time to melt. If you made it thick enough and managed to keep it cool before entering the corona, you might be able to have your probe survive minutes. Oh and... good luck sending data back.

 

[Lunar Pilot]

Well, if heat's the problem. . . .

There's always the unobtainium material found in the movie ''The Core''. Any heat will just end up strengthening it.

 

[T.Neo]

Or something that uses the suns energy to strengthen itself. Use the suns forces against it. Problem is, I have know idea what that would be.

Then you need some Unobtanium. It can turn the pressure and temperature of the Earth's core into electrical energy... by soldering the power cables onto the hull! :rofl:

EDIT:

Lunar Pilot beat me. The Core makes scientists cry, but I still wish I had a piece of that "unobtainium"...