Hot answers tagged

29

Short version: The planets of the system are small and the ecliptic is tilted vertically, and perpendicular as seen from Earth but the ship gets close enough to resolve an individual body or for its point of view to show transit events. Long version: There are five ways to find an exoplanet from Earth, we need to eliminate them all. So if you have a star ...


18

As built and installed in silos, those missiles aren't capable of reaching low Earth orbit, never mind going beyond it. This is because, as with everything in rocketry, they're built to deliver the maximum payload (the actual warhead bus with its MIRVs) to the maximum design range, typically (for American and Soviet/Russian missiles) an over-the-pole flight ...


16

The Electric Universe people were right. There are plasma filaments connecting all the stars, carrying incredible amounts of electric current. Only between the stars is it possible to tap into that energy, so the areas in the middle of the filaments are hotly contended.


14

The habitable "planet" is actually a moon of a super Jupiter. Telescopes in the Sol system were unable to resolve the moon from the planet it orbited. However, as the colony ship passed much closer to it on its way to the planet that was detected, they got a better look and spotted the moon. Edit An lengthier answer in response to comments: The ...


12

Energy generation In the vastness of space there is something. We don't know what it is or how to see it, but we can see it's effects. It pushes whole galaxies apart, while seemingly invisible. This is dark energy. There is a great abundance of it to be so powerful and most is likely in the vast emptiness of space between star systems and galaxies. Stars, ...


8

Vast voids which are devoid of gravity, particulate and radioactive interference are the perfect place to grow the flawless crystalline structures needed for the post-singularity level artificial intelligences. The computing power of any AI is strongly correlated to the size and purity of the circuitry that it lives in. Every supreme intelligence at the ...


5

By far the best natural resource is to be found in empty space is emptiness. The French tested nukes in the Algerian desert. Americans decided to nuke their own desert. Apparently deserts are fun to nukes. Well empty space is the desert of the universe. You can test all sorts of weapons, maneuvers, and other schemes far from prying eyes, and far from ...


5

the hypothetical situation in which SpaceX has partnered with NASA Instead of hypotheticals, why not look at the work they've already done together? This 2019 Business Insider article (paywalled, alas, though you can find text-only versions of the article in some less reputable places I shan't link to, just in case) took a look at some of the HiRISE image ...


4

Matter generation What we think of as empty space is full with activity. Thanks to fluctuations of the quantum field virtual photons pop in and out of existence, one positive and one negative, which cancel each other out. With light these can be turned into real photons, which means you can create something out of basically nothing. Uf you push this real ...


4

It wasn't visible from the original angle: Since you're talking about distances in 10s of years, I have to assume the planets we're going to are extrasolar (that is it orbits a different sun than our own/their own). If it has a very long orbit (Pluto take 247.78 years to orbit the sun), then perhaps it was just behind the sun the whole time! Once you got far ...


4

Have you ever walked in a fog so thick you don't see a pole until you slam your nose onto it? This is what might have happened: if in the line of sight between Earth and the planet there was something increasing the noise, the signal of the planet presence would simply become too small to be detected. It could be dust, it could be gas, it could be a more ...


4

a rocky-iron asteroidal shell around a void with enough volatiles to create some sort of atmosphere, when it is warm enough, contained in it. It seems unlikely: once a body starts to have significant self gravity, so that it is bound by it and not by electrostatic forces, also buoyancy starts to be sensible, and that will result in denser materials sinking ...


4

For a permanent base, it would be convenient to have water nearby! This is the North Pole of planet Mars,


3

It depends. All of the early rockets, at least in the United States, I'm not sure about the USSR, started life as missiles, and then were converted into tools for spaceflight. Given enough time (years) you can add upper stages to these missiles to loft payload to low earth orbit. Many modifications would have to be made. I'm not super familiar with the ...


3

Take Ceres Europa out of Jupiter's influence and throw it into space until it freezes to interstellar space temperature by radiation loss send it for some billions of year wandering in an iron rich nebula - perhaps you can find a cluster of old supernovas somewhere when you have a thick enough iron shell on top of some form of metallic ice, send it at ...


3

The simplest answer: the star, and it’s planets were not visible from earth because a nebula was in the way. Nebulas are clouds of gas and dust (mostly hydrogen) that obscure visible light. We don’t really know what may be on the other side of one and indeed something like half of the Milky Way is not visible to us because of obscuring nebula. So we can ...


3

Hiding valuable assets In a sufficiently populated galaxy, there could be countless potential threats and attackers in all directions, too many to keep track of or anticipate. Space is just too big. So instead of expensive force fields and hyper-sensitive early warning systems, every civilization will locate important installations in large regions of empty ...


3

Computation is more efficiant at lower temperatures https://en.wikipedia.org/wiki/Landauer%27s_principle So lets just say you are running tons of simulations you might want to get as far away from a heat source you can


3

Considering that the first settlers will have to deal with an hostile environment, a plausible location could be at the bottom of Valles Marineris, where atmospheric pressure is about as double as on the martian surface (see my other answer). Though not favorable to life, a lower pressure differential between inside and outside means a lower stress on the ...


2

Shipping lanes You can tax people for going through your "trade route", which has been done for centuries here on Earth. Set up space buoys to warn people they will have to pay a toll, or not, then enforce the toll. Not many governments would care about empty space, so they aren't going to war over the toll. They'll just go around it. Well, that is ...


2

Remember the last time you saw a sunset? This is basically what the moon sees before and after the totality of a solar eclipse. The sun is mostly obscured by the Earth, and the part which is not obscured by Earth shines through earths atmosphere. During a sunset, the light of the sun becomes orange and then red due to interactions with the atmosphere (...


2

I make no claim to sufficient expertise in astrophysics to assure you the following is credible... but I did sleep virtually (given a bit of literary license) in a Holiday Express last night, so you're in luck OK, I admit it, I slept very comfortably in my own bed last night. Still... Parallax: the effect whereby the position or direction of an object ...


1

(this answer assumes sub-lightspeed travel, say less than 30%) They came too close, the cloaking does not work anymore The newly discovered planet has an advanced civilization. Unfortunate events in the past were a good reason to develop a planetary cloak. This cloaking technology prevents the planet to be discovered by pirates roaming around the section at ...


1

I see two problems with this scenario. The first concerns the weapon. When talking about missiles it is helpful to break it down into the following sections This application would call for a new upper stage that combines the payload and guidance sections: an autonomous vehicle that will be able to track the incoming asteroid and deliver its weapon to it, ...


1

TL;DR: Big asteroids that pose a serious threat require nuclear explosives so powerful that they're more dangerous to the Earth than the asteroid might be. Small asteroids might be doable, but the consequences of failure are low enough that they might not be plot-interesting. Don't set off Earth-shattering kabooms a mere 5000km up. Intercept your asteroids a ...


1

It depends on trajectory, the impactor, and the Rambo factor. Every now and then a meteor really does bounce off the atmosphere. The rock doesn't have to be small, and some have claimed the immense Tunguska explosion was such an object. Given very, very good modelling of a type not really available at present, I can imagine being so sure that an object will ...


1

Stars are scary Stars spit out all kinds of radiation, they have flares and mass ejections and magnetic disturbances, sometimes they go nova, and in any case they have all of this stuff whirling around them all the time that might end up on an impact trajectory with an inhabited planet. Some people might find living on a rogue planet in interstellar space ...


1

Yes, during a lunar eclipse the moon is actually lit by a reddish light. The reason for this color is (loosely) because the light has to pass through the atmosphere in order to reach the moon - in effect the Earth acts a bit like a piece of red glass between the Sun and Moon. Therefore, if you have a moon base, during those moments, everything will ... be ...


1

forming Well, you need a volatile (icy) core covered in a rock or metal shell. This is the opposite of what happens normally when a melted body differentiates. There are bodies that are all ice. So let's start with that, and figure out how to make a hard crunchy shell like a cosmic M&M. Planets normally grow by accretion anyway. You just need to move ...


1

They're outlaws A race of people who make a living via piracy, raiding, smuggling, or other illicit activity might choose to hide out in the emptiness of space. The void is so large, it's just wildly impractical for the Space Police to even try to search for them in such a large empty region. It may not even be possible to reach those regions if your FTL ...


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