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28

Can I paraphrase Nietzsche while quoting Newton's third law of dynamics? When you punch the abyss, the abyss punches you too What is the difference between jumping and punching? When you jump you basically kick the ground so hard that your body is sent up by the reaction. Same would hold for this punching case. But let's look at some numbers, just for the ...


23

There's this temptation to consider the change in Mars' kinetic energy as totally transferred into our hero kinetic energy. But, you see, this is not to be that simple. Yes, the total energy is conserved, but Mars gets smashed in the process and a lot of energy gets lost as heat, kinetic energy of the Mars fragments flying mad through the solar system and ...


17

Probably such a body would not host life, no matter how long you wait. One can read everywhere that water is the basis for life, however a water only planet would be a terrible place for life to start, let alone evolve. Life as we know it rely on several elements in a water based solution. If you have only water and at most traces of the other elements, you ...


16

With an entire planetary core of osmium (even half of 5.9 * 10^21 tons is an absurd amount), diffusion, geological, and tectonic processes guarantee that large quantities of osmium compounds are present on the planetary crust and surface, much like compounds of the iron and nickel that make up the Earth's core are plentiful on the surface of the Earth. Note ...


9

Even if Mars were to be solid granite, or diamond for that matter, there is no material with sufficient stiffness to resist deformation when subject to a nearly infinite force. It would be like punching a cloud.


9

Of course it can. You need not look further than out next neighbour outwards. The moons Phobos and Deimos of Mars are distinctly asymmetrical: All that is required is that it is not massive enough to be formed into a globe by its own gravity, the so called hydrostatic equilibrium.


8

Since a human is similar in composition to a mole[citation needed], the treatise by Randall Munroe A Mole of Moles can give you a a good idea what the result would look like. Unfortunately, it doesn't seem to be very liveable: The outer surface of the planet radiates heat into space and freezes. Because the moles form a literal fur coat, when frozen it ...


8

I think the biggest impact will depend on whether osmium, at the temperature and pressure of the core the planet, would allow for the onset of a planetary magnetic field. Based on what we know, a planetary magnetic field helps protecting the planet atmosphere from depletion caused by the interaction with the stellar wind, which in turn will allow life to ...


7

It is not possible for someone to "punch" Mars to change course, because each force produces an equal force in the opposite direction. Means if there was a punch hard enough to do so, the opposite force would let your protagonist "jump" with the same energy, making him fly in the opposite direction much faster, probably near the speed of ...


7

Apart from the core being liquid and the many other mechanical issues with punching Mars to move it: Mars and Earth are both orbiting the sun, and the sun's gravity makes it impossible to just go in a straight line that hits Earth after 300 years (after all, it's enough to swing Earth in a complete circle 300 times in that time). At most, the remains of Mars ...


6

Your planet can't exist--most of it is going to be ice, not water. Check water's phase diagram--once the pressure gets high enough the liquid state no longer exists. It also will lack the radioactives to support a geological cycle. Heavy stuff falls down and doesn't ever come back up, your world soon can't support life even if it originally could.


6

Jupiter mass is $1.9 \times 10^{27}$ kg, your creature is half of that. Considering that Jupiter is already massive enough to perturb Earth's orbit, it;s safe to say that that thing should not get anywhere closer than somewhere between the Jupiter orbit and the asteroid belt, even though I am afraid that already its passing through the Oort cloud will cause ...


6

Short Answer: Because osmium reacts with oxygen to form the highly toxic osmium tetroxide, I substituted Iridim, which is almost as dense as osmium and much less toxic, in my calculations. Unfortunately, iridium is about as rare as osmium. A planet made of solid iridium with only a thin surface layer of other maderials would probably have too high a surface ...


5

and whose matter is made up proportionately of everything an average human body is made of? Simple: an ocean world, given that 70% of the human body mass is water. Except the radius will be about 1.7-1.8 times the current Earth's, given that the average Earth density is $5500kg/m^3$ and the average human body's density is very close to $1000kg/m^3$ And, on ...


5

That kind of axial tilt, like the somewhat weird rotation rate of Venus, seemingly is due to a large impact late in the planet's formation. Earth and Mars got 24 hour rotation out of that, Mercury got hit so hard it lost its crust and most of its mantle (but wound up with a long rotation period as well) -- and Uranus got turned over on its side. Now, can ...


4

The first issue I is that planet c is most likely uninhabitable, due to being a very close analogue to Venus. It orbits relatively close to the sun, receiving even more solar irradiance than Venus does. It's also been observed to have a very thick atmosphere likely composed primarily of water vapour, which would give the surface blazing hot temperatures, as ...


4

From space. Check the seasons. This can be done with computer modelling and space scanning. You want a place that has warm summers, cool winters, minimal rain, and few storms. If a place is filled with storms, is too hot, is too cold, or is constantly raining colonization will be harder. This can be done with a few satellites. Check if there are any ...


3

Additional information that may help: Twilight - the Sun is not seen over the horizon, but the light from it is still reaching the surface of the planet due to the various processes of interaction between the atmosphere and the sunlight. The practical definition of the twilight time varies on the specific purpose of that definition (and, with aliens in the ...


3

I used university simulator to simulate what a close encounter between Saturn (which is of a similar mass to earth) would do to earth. [][1 Here is Earth, happy and in a normal orbit. Here is Earth, in a rather unpleasant orbital distance of 1.45 AU after Saturn flashes near earth and a year passes. Saturn's Rings are notably wider than Jupiter. The Roche ...


3

Kind of a fun question. The problem is that it will depend a lot on the details. You could design your mega city badly and make it much worse by shadowing or design it some clever way and get sunlight to bounce around deeper in. Sunrise and sunset will depend a little bit on the altitude but not a lot. Several hundred feet will get you a 3-5 minutes, several ...


3

The main factor in answering this question turned out to be the requirement for having hydrogen and helium being largely absent from the atmosphere. According to the principle of Jeans Escape, at a temperature of 288K/15°C, Hydrogen and Helium are not retained in significant quantities until the planetary escape velocity is in excess of around 15km/s. Since ...


3

Send people and see if they survive. Make sure they pack a lot of guns for negotiating with fellow Earthlings or perhaps native fauna, and maybe a dust mask, sunscreen, some rations... In your scenario, there is a whole other planet of resources waiting to be taken. Every minute you wait is a minute someone else could be planting their silly flags and ...


3

For reasonably fast flow rates, it can only happen in a fluid planet, either made of gas or liquid, and it would not happen from the birth of the planet. It could be triggered by a massive impact, locally disrupting the flow of the fluid. It won't cause quakes, but the friction between the opposing flows would quickly dissipate the energy resulting in a ...


3

Not realistic long term under your conditions. Moon is tidally locked to Earth, while Earth is rotating freely (this is like what you want), but Earth is 81 times more massive than Moon. You want both bodies with 1g surface gravity, which necessarily makes their masses much closer. What you ask might be happening relatively early in binary planet system ...


2

This is not an exact answer, but so called "water worlds" may be the best candidates. Gliese 436 b is an exoplanet believed to be composed primarily of water. It's more than 4 times bigger than Earth and more than 21 times heavier, but its surface gravity is only 1.18 g Temperature, though, is too hot - about 439 °C, but this is a question of ...


2

The general category of rocks to consider would be those derived from ultramafic lava. Such rocks contain a large proportion of dark minerals, such as olivine and peridotite and dunite. A typical rock type would be komatiite. Soil derived from such lavas tend to have high amounts of nickel and chromium and thus can be toxic to plants. Distinctive vegetation ...


2

The core of a planet is so deep it's hard to imagine it having an impact on life With any terrestrial planet, the structure will be that there is the crust, the mantle, a molten outer core, and a solid inner core. The mantle can be divided into the upper and lower mantle. The lower mantle is about 670 kilometers before the Earth's surface. The molten outer ...


2

Lets look to our own solar system for the answers: https://solarsystem.nasa.gov/moons/jupiter-moons/europa/in-depth/ Europa is an ocean moon of Jupiter covered in Ice that is 15-25 km thick. It is fractured in multiple places, and based on observable craters is not more than 40-90 million years old. It is comparable in size to our moon. Yet in that time ...


2

In terms of retaining water in liquid phase what you need is a deep gravity well. You need to retain gaseous atmosphere at sufficient pressure to limit vaporisation of your water. Obviously 1G will do it; I don't know the lower threshold but Martian gravity (0.38G) isn't enough. Higher than 1G will certainly work. I think your world needs a significant rocky ...


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