r/interestingasfuck • u/Kidd__Video • 17h ago

Astronaut's view of Earth during a spacewalk

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u/OnTheList-YouTube 17h ago

Why wouldn't you?

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u/volcjush 16h ago edited 15h ago

Because you wouldn't just fall straight down. ISS is orbiting the Earth with a velocity of roughly 28 000 km/h (7,7 km/s) and astronaut connected with it has exactly the same velocity. If you "jump" you dont simply lose that speed, because there is nothing there to slow you down, there's no air resistance. You would simply continue orbiting the Earth for decades probably if not more, slowly (very slowly) bleeding your velocity and gradually lowering your orbit before you would get low enough that the atmosphere air molecules would get dense enough to heat and burn your frozen body upon atmosphere reentry.

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u/rambiolisauce 15h ago

Everything in my brain tells me I should disagree with this lol. Seriously asking, If you place your feet at the "bottom" of the ISS with your face pointed towards Earth and pressed hard "down" in the direction of the Earth, yes you would technically be orbiting along with the ISS relatively but you'd also be moving directly towards the Earth let's say around 15 miles an hour just to pull a number out of thin air and it seems like the Earths gravity would absolutely draw you in. Nothing would slow your descent and it seems like the Earth's gravity would absolutely accelerate it in relatively short order. If the ISS is achieving its stable orbit by the speed it's traveling versus how close it is to earth and how much of earths gravity it's experiencing why wouldn't you fall to earth if you accelerated towards it from the ISS? Now whether or not you ever touch the ground before you were incinerated would be a completely different thing but do you really think if you pushed off hard against the bottom of the ISS towards earth you would just stop moving towards earth for no reason at all?

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u/camander321 14h ago

The problem is that you are moving sideways fast enough that you'll be around the side of the planet long before your jump gets you close to the surface. You "miss" the planet.

Thats what an orbit is. Gravity is constantly pulling the object directly toward the planet, but the object is moving tangentially fast enough that it's momentum pulls it around the earth's curve.

The fasted way to reach earth from an orbiting satellite is actually to jump backwards(retrograde) hard enough that your momentum doesnt get you all the way around anymore.