While most planets have rocky molten cores, the center of Uranus is thought to contain icy materials. The liquid core makes up 80 percent of the mass of the planet, mostly comprised of water, methane, and ammonia ice, though it only extends to about 20 percent of the radius.

There is only one breed of Icelandic horse and it is the purest breed of horse in the world. It was introduced by the first Nordic settlers and is a stocky, thick-set and muscular horse.

Dales Pony Not only were many lost at war, but the ones that survived then became food for desperate people. Today, there are estimated to be less than 1000 Dales Ponies globally.

Based on his Copernican principle, J. Richard Gott has estimated that the human race could survive for another 7.8 million years, but it is not likely to ever colonize other planets.

Mars has a much thinner atmosphere than Earth and doesn’t have a global magnetic shield, so humans on the planet’s surface would be at risk of exposure to solar and cosmic radiation.

Habitability. Robert Zubrin has pointed out that Titan possesses an abundance of all the elements necessary to support life, saying “In certain ways, Titan is the most hospitable extraterrestrial world within our solar system for human colonization.” The atmosphere contains plentiful nitrogen and methane.

As a gas giant, Jupiter doesn’t have a true surface. While a spacecraft would have nowhere to land on Jupiter, it wouldn’t be able to fly through unscathed either. The extreme pressures and temperatures deep inside the planet crush, melt and vaporize spacecraft trying to fly into the planet.