When you’re interested in someone, you know things about them. Same story with the universe. You’ve probably never heard of the Sunflower galaxy or the quasar 3C273. But you can definitely name 12 celestial objects. Shouldn’t you know something cool about each?
This is the “famous dozen.” Whenever one comes up in conversation (which will happen sooner or later), it would be good if you possess some pertinent information. So here’s one vital, if generally little-known, fact about each. They’re worth memorizing.
The Sun. Little-known fact: It gets ten percent brighter every billion years. In just a billion years from now, it will be too luminous for any life to exist on Earth.
The Moon. It’s not made of cheese, but mostly oxygen: the same stuff you’re breathing. It’s got more than twice as much oxygen as anything else.
Mercury. This darkest of all planets has a surface matching an asphalt driveway. Yet it’s struck by such intense sunlight that it can still outshine every star in the sky.
Venus. Along with the Sun and Moon, it’s the only natural object that casts shadows.
Mars. Despite having only half Earth’s diameter, it boasts the same land area as our planet – because we’re mostly water-covered.
Jupiter. Its equator zooms along 24 times faster than ours, and this wild spin turns most of its features into streaks.
Saturn. This enormous ball with 95 times Earth’s weight is nonetheless so fluffy that it’s the only planet that would float on water.
Uranus. It’s green because its gassy surface has lots of natural gas: methane.
Neptune. Its one big moon, Triton, circles Neptune clockwise. This is the only major satellite with a backwards orbit.
Pluto. Locked into a strange gravitational resonance, it is forever banned from approaching Neptune. Instead, Pluto’s nearest neighbor is Uranus, even though that world is only half as far from the Sun.
Polaris, the North Star. Its height matches your latitude. If you live here at latitude 42, then Polaris is 42 degrees high: almost halfway up the sky.
Andromeda Galaxy. We’ll collide with this nearest spiral galaxy in about three billion years. It will make our night sky very different.
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