Colonization of the outer Solar System the Solar System's gas giant planets for exploration and possibly mining of helium-3, which could have a very high value per unit mass as a thermonuclear fuel. The Jovian system in general has particular disadvantages for colonization, including its severe radiation environment and its particularly deep gravity well. Its radiation would deliver about 3,600 rems per day to unshielded colonists on Io and about 540 rems per day to unshielded colonists on Europa. Exposure to about 75 rems over a few days is enough to cause radiation poisoning, and about 500 rems over a few days is fatal. Jupiter itself,
A Beautiful Planet twisted, inverted; you can completely lose your spatial awareness about where you are and what your attitude is, and you can easily get tangled up in that safety tether if you're not cautious. Every single movement you make, you're making an effort to think [things] through." After spending almost the entire film scrutinizing the Earth and the ISS (with its astronauts) in low Earth orbit, one of the final scenes of "A Beautiful Planet" briefly examines an important extrasolar planet (a planet outside of our solar system) which was discovered in 2014. The planet, Kepler-186f, was the first approximately-Earth-sized planet