12 New Moons For Jupiter Makes 79!

Galileo was the first person to see Jupiter’s moons. He eyeballed the four brightest through his small telescope on winter evenings in early 1610. When I was a boy Jupiter had 12 moons. More than 275 years passed before a fifth, Amalthea, was spotted in 1892. In the 1960s, a dozen were known. And by 2016,…
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Making Beauty With The Moon

Last night, we had a chance to see one of the finest conjunctions of the year. The moon and Venus looked incredible together. I happened to catch sight of the crescent just before sundown with Venus already bright and obvious 1½° to its left. Nearby, cirrus clouds caught the last solar rays and glowed with…
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ALCON 2018 — Connecting People With The Cosmos / Venus-Moon Stunner Tonight

Man, am I tired. But it’s a good tired. I’ve been away the past couple days in Minneapolis/ St. Paul, Minn. at the 2018 Astronomical League Convention (ALCON 2018). It was hosted by the Minnesota Astronomical Society (MAS), one of the friendliest and most engaged bunch of amateur astronomers anywhere. The yearly event brings in…
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Watch Asteroid Ryugu Spin Like A Top — In 3D

This is just too cool. You’re watching a time-lapse of the the kilometer-wide asteroid Ryugu spin on its axis. One complete rotation takes 7.6 hours or about one typical work shift. How many Ryugu rotations have you worked for the man this month? If you have a pair of red-blue glasses 3D glasses, put them…
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Colossal Collision Kicked Uranus On Its Side

Blessed is the 23.5° tilt of Earth’s axis. Without it there would be no seasons. How fun would that be? All the solar system’s planets spin on tilted axes, but none so much as Uranus, which nods 98°, a smidge past sideways.  Scientists have always wondered how Uranus got tilted so much that it spins…
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