Page 10 - Life beyond the Karman

Earth
Earth is the third planet from the sun, at a distance of about 93 million miles (150 million km), and the only place we know of so far that’s inhabited by living things.
It is a rocky planet with a solid and dynamic surface of mountains, canyons, plains and more. It is the only world in our solar system with liquid water on the surface. Earth is the biggest of the four planets closest to the sun, all of which are made of rock and metal.
Earth orbits our sun, a star. Its atmosphere is 78% nitrogen, 21% oxygen and 1% other ingredients—the perfect balance to breathe and live.
A day on Earth is 24 hours. Earth makes a complete orbit around the sun (a year in Earth time) in about 365 days.
Mercury
Mercury is the smallest planet in our solar system and nearest to the sun. It is slightly larger than the moon. Despite its proximity to the sun, Mercury is not the hottest planet in our solar system; rather, its neighbour Venus is. This is due to its condensed atmosphere.
Mercury is the fastest planet in our solar system – traveling through space at nearly 29 miles (47 kilometres) per second. Since it is the fastest and has the shortest distance to travel around the sun, it has the shortest year of all the planets in our solar system – 88 days.
Mercury is a rocky planet, also known as a terrestrial planet. It has a solid, cratered surface.
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LIFE BEYOND THE KÁRMÁN LINE - OUTER SPACE