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Daniela Breitman

Today in science: Pluto the dwarf planet

August 24, 2016 is the 10th anniversary of astronomers’ announcement of Pluto’s demotion to dwarf planet. The decision caused a shock wave around the world.

Today in science: Gene Roddenberry

Happy 95th birthday to writer and producer Gene Roddenberry, creator of Star Trek.

Astronomers see a star’s water snow line

First distinct (resolved) observation of a water snow line – aka a frost line – the distance from a star where temperatures drop so low that water turns to ice.

Ultra-Deep Survey probes distant galaxies

The survey shows 250,000 galaxies in an area of sky 4 times the size of a full moon. It’ll be used to help trace galaxy evolution over the last 13 billion years.

Today in science: Egypt’s first meteorite

It was the first meteorite in the Egyptian record. Years after the event, scientists concluded through various tests that it came all the way from Mars.

This date in science: Jan Oort’s birthday

Visualize a vast reservoir of icy comets on the outskirts of our solar system. That’s what Jan Oort did in 1950, and why the Oort Cloud bears his name.

Today in science: Comet Hale-Bopp

The last widely seen comet for the Northern Hemisphere was Hale-Bopp in 1996-97. Did you see it?

This date in science: Galileo’s birthday

Happy 452nd birthday to one of the first modern scientists, Galileo. With the aid of an early telescope, he helped remove Earth from the center of the universe.

This date in science: Clyde Tombaugh, discoverer of Pluto

This is the 110th anniversary of Clyde Tombaugh’s birth. He was a farm boy who loved astronomy and ultimately discovered Pluto. Planets X and Pluto, here.

Corona around the moon

These colorful rings of a lunar corona appear when we see the moon through a very thin cloud of similarly-sized water droplets.