Mon Apr 10, 2023 STAR COMPARISONS
The stars we see this evening include the red giant Betelgeuse, in the western sky in the constellation Orion; it’s a billion miles across. Another star in Orion, the blue giant Rigel, is many times hotter and more massive than the sun. There’s a white dwarf, a companion star to brilliant Sirius in the southwest, which is no bigger than the earth. And there’s a tiny neutron star, just a few miles across, within the borders of Taurus, while a black hole, a mere pinpoint of super-dense matter, lies just to the east of Orion. From red and blue giants to yellow suns, white dwarfs, neutron stars and black holes, from solitary suns to great star clusters, each star is unique, possessing within it the secret of its own creation and demise.
Tue Apr 11, 2023 SEASONAL CONSTELLATIONS
With the new season, there is also a change in the constellations in our evening sky. Orion the Hunter and his entourage - Taurus the Bull, Canis Major and Canis Minor (that is, the greater and lesser dogs,) Lepus the Hare, Auriga the Charioteer, the Gemini twins and Cancer the Crab – have slipped over into the western sky; while new star groups rise out of the east. The stars of Leo the Lion appear as a backwards question mark above the eastern horizon, while the Big Dipper stands on its handle in the northeast after dusk; and soon bright Arcturus in Boötes the Shepherd and the star Spica in Virgo the Maiden will rise. The sky wheels about us, and the springtime constellations take their places in the heavens above.
Wed Apr 12, 2023 YURI GAGARIN
On April 12th, 1961, the first human was launched into space. It wasn’t John Glenn, he was the first American to orbit the earth in a Mercury spacecraft. It wasn’t Neil Armstrong, he and Buzz Aldrin were the first astronauts to land on the moon. It wasn’t Alan Shepard. He was the first American to go into outer space, but that happened almost a month after the first man orbited the earth. Yuri Gagarin, a Soviet cosmonaut, was first. It was a smooth launch and orbit, but the way Gagarin came back to earth was scary. His Vostok spacecraft didn’t have enough parachutes to slow it down without leaving a small crater, so several miles up, Gagarin was ejected from the capsule, and then had to parachute down to the ground all on his own – now that’s exciting!
Thu Apr 13, 2023 LEVIATHAN MIRROR
On April 13, 1842, the mirror for the Irish Leviathan was completed. It was six feet across, and was built by William Parsons in Ireland. It was a metal mirror, an alloy of copper and tin. Installed in the fifty-six-foot-long telescope tube, it became the Irish Leviathan, and for the next seventy years, it was the biggest telescope on earth. Parsons observed stars, the moon, and the planet Jupiter. Then the potato famine hit Ireland, and it was shut down. But in 1845, Leviathan was running again and Parsons observed M51, a large nebula in the constellation Canes Venatici. He called it the Whirlpool, describing it as a "spiral nebula". Parsons even saw individual stars in the Whirlpool, and thought that it was a distant galaxy, similar to our own Milky Way. He was right.
Fri Apr 14, 2023 HOW THE BEARS GOT THEIR TAILS
The constellations of Ursa Major and Ursa Minor are in our northern sky tonight. Star charts depict these bears as having long tails, which bears don’t have. In an old myth, Zeus loved the maiden Callisto, but his wife, Hera, turned her into a bear. Now Callisto had a son named Arcus, who when he grew up, ran into his long-lost mother out in the forest. Fearing for his life, Arcus aimed an arrow at her, but Zeus kept him from killing her by turning him into a bear as well. To keep them safe, Zeus grabbed Arcus and Callisto by their short bear tails and dragged them up into the sky, where they became constellations. In the process, he stretched out their tails, which is why they’re so long. You may think that’s stretching a tale a bit, but these are the bear facts.
