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,
Akaa Solar System Scale Model man-made spacecraft) and the concrete pillar representing its location is at the center of the neighbouring town Viiala, approximately 7 km away from the Sun. The speed of light in the scale model is exactly 10 cm/second, so walking the 50-meter distance from the Earth to Sun "at light speed" takes 8 minutes and 20 seconds. In 2018 scale model of Proxima Centauri -star was added to Akaa Solar System Scale Model. Proxima Centauri is a red dwarf star and the nearest star to our Solar System. It is located 4.24 light-years away and in the model's scale it has