Page 14 - Life beyond the Karman

Neptune
Neptune is dark, cold, and whipped by supersonic winds and ice. It is the eighth and most distant planet in our solar system at a distance of about 2.8 billion miles (4.5 billion kilometres) from the sun.
More than 30 times as far from the sun as Earth, Neptune is one of the planets in our solar system not visible to the naked eye and the first predicted by mathematics before its discovery.
In 2011, Neptune completed its first 165-year orbit since its discovery in 1846.
Neptune is about four times wider than Earth. It takes about 16 hours to rotate once (a Neptunian day), and about 165 Earth years to orbit the sun (a Neptunian year). Its atmosphere is mainly made up of molecular hydrogen, atomic helium and methane.
be many more dwarf planets – perhaps more than a hundred waiting to be discovered.
Pluto
Pluto is by far the most famous dwarf planet. Discovered by Clyde Tombaugh in 1930, it was long considered our solar system’s ninth planet. However, after other astronomers found similar intriguing worlds deeper in the distant Kuiper Belt, the International Astronomical Union (IAU) reclassified Pluto as a dwarf planet in 2006.
Ceres
Ceres is the largest object in the asteroid belt between Mars and Jupiter, and is the only dwarf planet located in the inner solar system. Like Pluto, Ceres was once classified as a planet. It was the first dwarf planet to be visited by a spacecraft – NASA’s Dawn mission.
Haumea
Haumea is located in the Kuiper Belt, a doughnut-shaped region of icy bodies beyond the orbit of Neptune. It is roughly the same size as Pluto and is one of the fastest rotating large objects in our solar system. The fast spin distorts Haumea’s shape. Haumea has been described from observations using ground-based telescopes from around the world. It is extremely cold and does not appear to have conditions suitable for life.
With a radius of about 385 miles (620 kilometres), Haumea is about 1/14 the radius of Earth. It is 43 astronomical units from the sun. One astronomical unit is the distance from the sun to Earth. From this distance, it takes sunlight six hours to travel from the sun to Haumea.
Haumea takes 285 Earth years to make one trip around the sun. As it orbits the sun, it completes one rotation every four hours, making it one of the fastest rotating large objects in our solar system.
Dwarf planets
The International Astronomical Union (IAU), a world organisation of astronomers, came up with the definition of a planet in 2006. According to the IAU, a planet must meet three criteria:
1. Orbit its host star (In our solar system, that’s the sun);
2. Be mostly round;
3. Be big enough that its gravity cleared away any other objects of similar size near its orbit around the sun.
Dwarf planets like Pluto were defined as objects that orbit the sun, and are nearly round, but have not been able to clear their orbit of debris.
So far, the IAU has only recognised five dwarf planets. In order of distance from the sun they are: Ceres, Pluto, Haumea, Makemake, and Eris. However, the IAU notes that there may
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LIFE BEYOND THE KÁRMÁN LINE - OUTER SPACE