Mon Dec 15, 2025 TYCHO BRAHE
Tycho Brahe, born on December 14th, 1546, was a Danish nobleman who had an artificial nose made of brass – he’d lost his original nose in a fencing duel over an argument with another scholar about a math problem. (Actually, this happens a lot. Not the duel, the arguing.) But it turns out he was a great astronomer. Tycho proved by its parallax that a comet was far beyond the moon; it used to be thought that comets were simply gases in the atmosphere. From Tycho’s island observatory, and before telescopes were invented, he made incredibly accurate measurements of star and planet positions. It was this data that made it possible for his colleague Johannes Kepler to figure out that the shapes of the orbits of planets about the sun are not round, but elliptical.
Tue Dec 16, 2025 ORION’S RETURN
The familiar constellation of Orion the Hunter rises out of the east around 8 o’clock tonight. In Robert Frost's "The Star Splitter," the poet begins by saying, "You know Orion always comes up sideways.Throwing a leg up over our fence of mountains, And rising on his hands, he looks in on me Busy outdoors by lantern-light." Orion does come up sideways, first his left shoulder, the star Bellatrix, and the hunter's knee, the blue-white star Rigel; then the three bright belt stars come up in a line, followed by Betelgeuse in Orion's right shoulder, and finally his right leg, the star Saiph. When I was young, I saw Orion, looking just as he does now, as did my grandparents, and their grandparents, and so on back for thousands of years.
Wed Dec 17, 2025 JOHANNES KEPLER
Johannes Kepler, born on December 27th in the year 1571, believed in Copernicus’ theory that the earth orbited the sun. But while Copernicus had a beautiful idea, he held on to the ancient notion that the orbits of planets were perfectly circular. Now the data that Kepler used, obtained from the painstaking observations of the Danish astronomer Tycho Brahe, didn’t support that notion. Unlike past theorists, Kepler refused to toss out the data, which he knew was accurate. Instead he discarded that perfect round circle theory and introduced a new one: the orbits of planets are elliptical. Once elliptical orbits were calculated, the motions of the planets became understandable and predictable.
Thu Dec 18, 2025 BRIGHT STARS OF LATE AUTUMN
Many bright stars, and even a couple of planets, can be found in this evening’s sky. The stars Vega, Altair and Deneb, are over in the west after sunset. In the southwest is a yellow-tinged star, actually the planet Saturn. But the eastern sky contains the bright stars of winter. The constellation Orion, with red-tinged Betelgeuse in his shoulder and the blue white star Rigel in his knee, along with the three belt stars, which point upwards toward Aldebaran in Taurus and downward to the Dog Star Sirius near the horizon; high in the north is yellow Capella; but the brightest star is to the east of Orion and below the stars Castor and Pollux in Gemini and above Procyon in the constellation of the Little Dog. It is Jupiter, the king of the planets!
Fri Dec 19, 2025 WINTER SOLSTICE/URSID METEORS
Winter begins in the earth’s northern hemisphere on Sunday, December 21st, at 10:03 AM, Eastern Standard Time. It's at this exact moment that the sun's rays fall most directly on the Tropic of Capricorn, twenty-three and a half degrees below the equator, where summer is beginning. For us in the northern hemisphere, today marks the shortest period of daylight, and also the longest night of the year. As our winter season begins, we will be treated to a meteor shower called the Ursids. Best views will be from midnight until dawn, but there will be some visible in the late evening too. Grab a reclining lounge chair, dress warmly, get away from bright streetlights and face east, and hope for clear, dark skies.
