# Tag Info

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A big fan. Your aliens are so astronomically ineffable, the fans will tear them to pieces. Think of it as a teleporter set to Maximum Dispersion, without the need to lose a few crewmen experimenting with it on the maiden flight. We know from so many classic video games that any unstoppable combat monster who can take hits from rocket launchers and gargle ...

6

The largest terrestrial predators are big cats, bears, wolves, and humans. (And, I suppose, other large primates.) Cats and humans are probably the best ambush predators from the group. So, eyes like humans or cats. More likely humans, since we're around 6 feet tall and bipedal, descended from semi-bipedal ancestry.

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The easiest way to identify itself as of alien origin would be to provide a large amount of scientific information that is not available on Earth but which could be tested immediately and or in the coming years and decades. For example, describing the theory of everything that physics has been searching for as well as a test that could be conducted to ...

6

A: Its parts MUST be interconnected by something, meaning its parts can be taken apart. You can not actually make anything intelligent out of a true gas because gas is constantly reconfiguring itself. A memory is formed by creating a network of connections that can be repeated. If your body is just drifting around formlessly, then it can not create a ...

6

Sight based on forming images from photons would indeed be completely pointless, but basically everything else is on the table. Taste/smell: most magmas have a lot of dissolved volatile molecules like water, carbon dioxide, hydrogen sulfide, etc. Especially the less-viscous ones that would be easier (not easy, but easier) to swim through. Also lots of metal ...

5

The analogue for echolocation in earth sciences would be reflection seismology, in which a shock wave is generated and the acoustic reflections give information about the surroundings. Like echolocation, it is very coarse information, only identifying large-ish things that are nearby. Smell is rather implausible. The diffusion rate through lava would be ...

4

Pupils The standard answer most biologists would give you is that the pupils would be vertical slits because this allows better judging of distances: Species with pupils that are vertical slits are more likely to be ambush predators that are active both day and night. In contrast, those with horizontally elongated pupils are extremely likely to be plant-...

4

"Bipedal" and "predator" make me believe that the most optimal configuration of eyes for this creature is eyes on the front of its head, which can see further due to being further off the ground. Additionally, predators don't need to look to their sides. They're the threat - they don't need to look for threats, at least to the level of ...

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The most plausible way to "sense" something in lava seems to be echolocation: sonic waves bouncing off the interfaces between the lava and the other body, possibly at frequencies outside the range of noise produced by flowing lava, just for the signal to not be drown into noise.

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Obligate carnivores, you say, eh? Like in "lack the necessary physiology required to fully digest" plant matter. Some consequences - not necessary true but plausible (so don't quibble too much over details) their agriculture is mostly based on raising livestock - they can't be hunters and reach a high degree of civilization, they need to take the ...

3

Phase change Without knowing anything about the biology of these gaseous creatures, I can reasonably guess that making them not-a-gas would be catastrophic for them. You can turn most any gas into a liquid or solid by increasing the pressure or decreasing the temperature. Turning them into a liquid might not be deadly since it's still a fluid that allows for ...

3

Change their chemical structure Once someone understands the beings chemical structure, you can develop methods to alter the chemical structure. Even Helium atoms can form compounds under great pressure or when their ionized. Change their Atomic structure You can also destroy it by changing the Atomic that make it up. You destroy them by using the same ...

3

Show things only aliens might know The aliens are bound to have a bigger understanding of the universe. They somehow cracked every language on Earth, so further knowledge isn't a stretch. In that vein you can go much further. As they know every modern language it is very likely they know the state of modern technology. With this they can direct scientists to ...

3

It should be as simple as eliminating any possible scam motivation. This isn't easy though, because humans are inclined to create hoaxes for the sake of hoaxing. However, when that happens, it is rarely more than a handful of people in on it. Most bigfoot/cryptid sightings are 1-3 people, and the crop circle folks had up to half a dozen. This device might ...

2

Show future knowledge. If the device has ftl communication between it and the creators, then it by nature is a time travel device. If there are stellar events closer to them than you, they can report what the light from the stars does before you do, and relay this information. Do computational tasks faster than them. The earth scientists could also send them ...

2

Forward-facing eyes with round pupils, probably not much bigger than a human's, if at all. Your creatures are predators that seemingly rely a fair bit on vision, therefore, the best configuration relative to the skull would be a more forward facing one, as it allows a wider range of binocular vision, making them better at perceiving depth. As for the pupil ...

2

the cosmic abundance of uranium-238 is 1 to 1 trillion particles. It seems like very rare, but let's roll some numbers. The mass of Earth is $5.9 \times 10^{24}$ kg. The molar mass of iron is 55, meaning that a mole of iron has a mass of 55 grams. That means that, roughly speaking, Earth is made of $10^{26}$ moles of iron, if it was made of entirely iron. ...

1

high voltage basically just shoot them with lightning. where it hits directly, the gas turns into plasma - that would be the equivalent of burning an organ to a crisp. additionally, the strong electric field will greatly disturb whatever inner workings keeps them coherent, scrambling not only their physical "bodies", but also their consciousness. ...

1

It wouldn't be killing them per se, but can't you just suck them up with a vacuum cleaner. You could connect it to a container and store them. Once they are in a container it could be easier to kill them, extreme heat or cold come to mind, or blasting them with lethal doses of ionizing radiation could do the trick. It depends on what they are susceptible to. ...

1

Supernovae and planet age The abundancy of Uranium and other heavy elements depends on the proximity of supernovae at the time your planet was formed from the proto-planetary disk. It also depends on the age and development stage of your planet. My answer is mainly a link, https://world-nuclear.org/information-library/nuclear-fuel-cycle/uranium-resources/the-...

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The most important question is "does the planet in question have abundant oxidizers?" Uranium Oxide Heavy metals, left to their own devices, tend to sink towards a planet's core. But uranium oxides, fluorides, and chlorides are all much less dense. So as long as, during the early stages of the planet's formation, these compounds form (or arrive ...

1

Sure! The limbs, as per the first centauroid sketch, are in perfectly normal mammalian posture. There's not enough of an offset to make the legs look at all buggy. The only significant difference obviously visible is that the hands are much longer than a humanoid centaur, and that's not a problem at all! Since these are arthropod centaurs, I don't see ...

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All elements on earth have a particular atomic signature. Ratios of elemental isotopes contained in a sample from the devices construction. For instance if you made a knife on earth, and made and "identical" knife on mars. You could analyze the ratio of iron among all of the other present isotopes to identify not only which knife was Martian, but ...

1

Yes living things can survive being exposed to space, but navigating is much more difficult. As you probably know by now, Tardigrades (moss piglets) are microscopic bacteria eating critters that can survive extremely well in harsh conditions. They hibernate through the hard times in a pretty much dead state like a dried raisin, this process is called ...

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