Space.... the final frontier. It's the unknown we ALL need to know about. Space and the human brain are two of the few things we know least about. It is a fascination and an enigma. There is no definite... or so some of us believe. Is there life out there? Wouldn't you like to know? Well.. maybe...
Hawaii already has those...
That Pluto has cryogenic volcanic activity.
Literally ice volcanoes. Misanthrope_penguin
Mars is over...
This is pretty debatable, but: on Mars is the biggest mountain in the solar system, Olympus Mons. It's huge, but it's so spread out it would be an easy climb: you could just walk right up it (which of course would be even easier in Mars surface gravity).
By some definitions of "space," the top of Olympus Mons is actually in space.
Thus on Mars it is possible to WALK TO SPACE. autoposting_system
Let the Sunshine!
The Sun holds 99% of all the material in the Solar System. Jupiter by itself is more than half the rest. Yes, Jupiter is more massive than all the other planets, moons, comets, asteroids put together. NoAstronomer
This is above my pay grade...
The rotational energy that originated from the molecular cloud that collapsed to create the solar system is stored in the planets. Angular momentum is a strictly conserved property that you can transfer but not create or destroy. A closed system will always conserve it. Moving mass closer to the center of the object accelerates its rotation because the angular momentum has to be conserved.
Example: ice skaters spin faster by closing in their arms on themselves. You can do it at home too if you have a chair that spins. Sit on the chair and get a large book in each hand. Extend your arms, start spinning and now close in your arms. You will accelerate A LOT.
What happens in a solar system is that planets hold this energy in their spin (rotation). As the gaz cloud contracts, molecules collapse into a planet and the resultant of this accretion is the accumulation of the momentum into the planet. This is why (large) planets such as Jupiter, Saturn have such fast days (10 hours) compared to the Sun (about 27 days). The Sun, at the center of the solar system, has inherited the molecules that had low momentum, and its resulting momentum is low. a_postdoc
Too close for comfort!
The ISS is only 200 ish miles away from Earths' surface. i drive more than that every week. It's crazy close. RusstyDog
Pluto hasn't even gone halfway around the sun since it was discovered! vaccumshoes
It's a Champagne Supervova in the sky...
It's entirely possible (although very unlikely) that we'll watch it supernova in our lifetime. A star of the magnitude of Betelgeuse exploding is an event that would make front page headlines in every paper. We'd pretty much have to give up stargazing for an entire year because the night sky would be too bright ... not sun bright, but brighter (NOT bigger) than the moon. And even given Betelgeuse's incredible size, it's still not massive enough to collapse into a black hole and would instead collapse into a neutron star after supernova'ing.
Thankfully though, given it's distance of ~650 lightyears away, the explosion poses no threat to us here on Earth whatsoever. We simply get a nice lightshow out of it. RedditingAtWork5
The Black Hole...
There are Neutron Stars which are extremely dense, just short of turning into a black hole, they are as big as the Mount everest and they spin extremely fast. They also have an Atmosphere of 10 cm. If you drop something at the height of 1 meter it accelerates to 7,2 Million KM/h at the point it hits the surface! Stalkopat
Depending on your perspective, of course. At that kind of acceleration, gravitational time dilation is going to start seriously affecting your measurements across different reference frames. Relativity is a bitch. Rust_Dawg
The Planet or the car?
Saturn would float if you had enough water. LapinHero
Are they a split personality?
The Sun and the Moon appear to be the same size from Earth. There is no reason for this, it's just pure coincidence.
Right now, yes, which makes it even spookier. At this moment, from this spot, are our sun and moon of equivalent apparent size.
We are living in anomalous circumstances, whether or not we care to admit it.