# Would a submarine float in the atmosphere of Jupiter?

Would a submarine float in the atmosphere of Jupiter, or would it get crushed?

• I think the question is, "Where in the atmosphere of Jupiter would a submarine's operating depth be?" May 4, 2011 at 15:19
• Even more interesting, the "Operating depth" which is typically limited by the pressure at which the submarine will be crushed, may or may not be the same as the depth at which it would float, which is governed by the density of the surrounding gas. In the ocean the water density is roughly constant, and pressure increases with depth. On Jupiter, at least where the atmosphere is gaseous, both pressure and density vary with depth. Hat I more time, I'd love to work out an answer to this question. Maybe later. +1 May 4, 2011 at 15:26
• Jupiters atmosphere is predominantly H2 and He, isn't it? Is a temperature profile known? May 4, 2011 at 17:50
• It would be nice if you could update the question according to suggestions in comments; use "edit" link.
– user68
May 4, 2011 at 18:35

## 2 Answers

As the comments above indicate, factors like density, pressure and temperature are important for a Jupiter submariner. Of course nobody yet has the exact details of Jupiter's interior structure, but there's a diagram in this LASP page[WebCite archived version] that indicates the following: At the intersection of Jupiter's liquid hydrogen/metallic hydrogen layer, the density is about $1\text{ g}/\text{cm}^3$, which would permit the submarine to float. However, the temperature there is $\sim5000\text{ K}$, and the pressure is $\sim2 \times 10^6\text{ bar}$, so it can't be done with normal equipment.

Short answer: It would get crushed.

Long answer: See today's "What If" on http://what-if.xkcd.com/138/

• Welcome to Physics! This post could be better if you summarized Randall's argument moreso than the "it would get crushed" you've given. This is otherwise a link-only answer that are generally not well-received here. Jul 28, 2015 at 21:00
• Wow, my question has reached Randall! Jul 30, 2015 at 8:25