Alien exploration : drone digging earth crust

Question

I was thinking of potential planet explorations, by extremely advanced alien species, through automated drones (or "flying laboratories") scanning and analyzing the planets. (By "extremely advanced", i mean they lived for millions or billions of years, mastered every possible laws of physics, can manipulate and use antimatter and whatever other matter we don't really know exists like dark matter, exotic particles ... and travel through space via wormholes)

I came to a point where analyzing the crust and and core of a planet would be a problem. With today's technology, I read we can't drill deeper than what we actually drilled (~12km) because of the high temperature and the "toughness" of the rock.

The drones can fly in stationary, are really numerous (millions per planets), has very high energy autonomy (like, fusion battery) and resist to high temperature and pressure thanks to technologies we don't know yet (a.k.a. "protection shields"). They are not conveniently perfect. I know I say they are extremely advanced, but I guess we can't just throw those drones into the sun, because of certain laws of physics (magnetism, dangerous "rays", >1,000,000 C°...)

Then, with this alien technology, would it be possible to "vaporize" the rocks with an extremely hot laser beam to "drill" to the core (at least the liquid part of the core to "swim" in) ? If not (rock collapsing ?) what could actually help to dig to the core ? nanotechnology ? cooling the core of the planet ?... (consider you have unlimited resource and energy, not infinite but in very large amount)

For the sake of the story (and the whys) : these aliens are so advanced in everything, the last thing they don't know is "what is the universe looking like ?", so they decided to analyze every single planet, stars and "objects" of the universe, looking for resources (to make more drones, "refuel" ships etc...) and for signs of life. They are pacifists (they don't need to conquer anything), respect planets with life and let it develop (but they still analyze it)...

thanks for your answers, or whatever comment you post to help me resolve this tiny problem.

Answer 1

You don't need to touch something to be able to science it. Scientists use indirect methods all the time.

One used by Earth geologists is seismic analysis. Measuring how earthquakes propagate through the crust at certain spots, we can infer how they have been moving through; and thus, certain properties of the materials (such as density). Our geologists have a bunch of sensors dispersed around the world, but the number of them is limited by the available funding. Your advanced aliens could create a much denser net of much higher quality, including deep in the sea, that would give them much more information.

Even more, the aliens could trigger the quakes in a controlled fashion. This has two advantages: you know the initial conditions much better, and you can improve the mapping of the area you want (areas like Japan would be very well covered, whereas Scandinavia would yield much less data). Of course, the energy released for inhabited planets should be of very low yield, but their sensors can figure it out.

Having a lot of material available, another possibility is to make ground penetrating radar at a ridiculous scale. We, puny humans, have a tiny antenna that we wave over the ground. Our overlords aliens could dig a network of small holes in the ground, going a few kilometres deep, and use it as an array of antennas. Once you are a few metres underground, the electromagnetic noise is going to be negligible, so you will only pick up your own signals.

Both methods can give you a pretty good idea of the interior of a rocky planet, and with some adaptations, a gas giant. To get a better idea of the composition, you can just nuke some of the asteroids and planets (who liked Mercury, anyway) to analyse their chemical interior. Since all the Solar System has a common origin, that should give us enough information.

There is of course a remaining problem: not all planets are as nice as Earth. Venus, for instance, has a very hot atmosphere, with a crushing pressure, and intense acid rains. If you want to probe it in any way, your drones must be able to withstand punishment. Gas giants present also harsh conditions: supersonic winds, high gravity and pressure, big temperature gradients... And this is only what we know from the solar system. Who knows what lies out there.

Also, don't underestimate the power of computer simulations. With enough CPU power and knowledge, we can do high resolution simulations that can tell us many things that are impossible, so only a few actual experiments are necessary. In our case, the nebula that gave rise to the solar system should be able to produce four rocky planets and four gas giants of the appropriate masses and compositions; if you can't make it happen without having between 1.23% and 1.24% of silicon, there should be that much.

Answer 2

Given the aliens have worm hole technology to travel about, they can use this to create a wormhole to the core of the planet and post the probe through. This goes around the problem of digging your way down through the planet.

Alternatively you could use the wormhole to extract a chunk of the planet to science it, this would be an easier option as you don't have to make the probe survive the insane temperatures and pressures of the core.

If you want to make this not work in your universe I suggest making your worm holes not work inside of a gravity well. This would force your aliens to wormhole their way around from the edges of systems.

Answer 3

The current issue of Scientific American discusses Dark Matter. There may be multiple kinds, with a small part of it interacting with its own regime and possibly form "dark atoms" and such.

Make the probe out of that. Have it sail through the planet like a ghost, the dense and hot rock being but a tenuous shadow.

Answer 4

Ignoring the wormhole-to-the-core possibilities, i think that how it might work is if the drones are equipped with

a) some beam or drill which can cut through any earthly matter (ie molten or solid rock)

b) some equipment to suck in this material and use some of it to build tunnel walls which are impervious to said molten rock and can withstand the pressures involved: i'm picturing some sort of matter compiler/decompiler which can take rock, zap it into atoms, and then build tunnel walls made of diamond or some other very hard substance.

Then, it should be able to cut its way downwards, building a tunnel as it goes. It would work best if the tunnel's cross section perfectly matches the drone's (and this would be simplest if the drones were spherical) as they will then block the tunnel as they go down. This will a) prevent environmental catastrophe due to making a volcano behind them and b) keep the tunnel behind them empty, so they can send samples back up to the mothership or something.

When they're done they can cap the tunnel, leaving a stable, very deep, hole in the planet. If they want to be responsible, they could somehow dissemble it on the way out, although not making a volcano in the process would be tricky.

Answer 5

Building on @DavidMh's answer, you don't need to touch something to science it. While it is true that millions of years of scientific research will yield some ridiculously powerful instruments, those instruments are only half the picture. The other half is the data analysis capabilities of an advanced civilization.

For example, the Hubble is now about 25 years old and it just discovered a "sunscreen layer" on a distant planet. With the exception of the Hubble's contact lens "surgery" from early in it's career, it's capacity to gather data hasn't changed. What's different now is that we have far greater ability to model and analyze the data it sends to us, and we know where to go looking for interesting things.

So an alien race advanced enough to control dark matter and dark energy could easily build a machine to burrow to the Earth's core but they probably know a thousand ways to get that info faster and with higher resolution than sending a probe. Heck, maybe they've figured out how to make neutrinos useful as a massive scanning mechanism.