Skywatch Line for Monday and Tuesday March 3rd and 4th, 2024 written by Joe Slomka

This is the Dudley Observatory’s Skywatch Line for Monday and Tuesday March 3rd and 4th, written by Joe Slomka.

The Sun sets at 5:29 PM; night falls at 7:23. Dawn begins at 4:50 AM and ends with Sunrise at 6:24.

Monday’s Moon finds the 23-day-old Moon in southeastern Ophiuchus, rising at 4:24 AM and setting at 1:04 PM, just past Last Quarter. By 5:30 AM, Tuesday, it now inhabits southeastern Sagittarius, rising at 3:31 AM, 31 arc-seconds in size, 31% illuminated and sets at 11:51 AM. About 45 minutes before Sunrise, the Moon can be found in the middle of Sagittarius’ “Teapot”; this unusual sight occurs because the Moon is unusually low in the South.

Western Jupiter and Uranus are the only evening planets, sharing Aries and rising during daytime. Jupiter now lies low, flashing with minus 2nd magnitude, 36 arc-seconds, 39° high at 7 PM and sets at 10:35 PM. The Great Red Spot (a giant storm) is visible at 8:30 PM on Monday. Jupiter follows Saturn, Neptune and Mercury in heading for the Sun’s glare. Uranus, 6° behind Jupiter, shines with 5th magnitude, 3 arc-seconds, 46° high and sets at 11:17 PM.

Mars is the first Dawn planet, sharing Capricornus with Venus. The Red Planet rises in the Southeast at 5:34 AM, shines with first magnitude, 4 arc-seconds, 6° high at 6 AM and 97% lit. Mars rises daily, still close to the horizon. Venus is closer to the Sun, dipping daily; it blazes with minus 3rd magnitude, 11 arc-seconds, rises at 5:36 AM, 4° high, 92% lit and 4° at 6 AM. Now it’s the time for last looks. Both set in the afternoon.

Two comets occupy the Dawn sky. 12P/Pons-Brooks is still visible in the Northeast, it rises at 4:18 AM, 7th magnitude, 90% lit, 8° high at 5 AM and sets at 9:47PM. Comet C/2021 S3 (Panstarrs) lies in Serpens, 38° high in the Southeast, also 7th magnitude, 86% lit, rises at 1:29 AM and sets at 1:22 PM.

Johannes Hevelius (Jan Heweliusz) was a Polish astronomer in the port city of Gdansk (also known as Danzig). Prominent in local politics, he was first a beer brewer, but his true passion was astronomy. In 1641, he built a private observatory (dedicated to king Jan Sobieski) that included a 150-foot telescope, but did most of his work with a six-foot brass sextant. He was inducted into Britain’s Royal Society in 1664. In 1679, fire destroyed his observatory. He memorialized his loss with an invented constellation, Sextans, and rebuilt his observatory. Sextants contains an arc, one-sixth of a circle and has a moveable arm measuring angles. Sextants still exist. Sailors use a version which includes a small telescope on the swinging arm and mirrors. Along with an accurate clock and astronomical almanac, the navigator locates his position at sea. That skill is being lost to the increasing use of GPS to fix a position with unprecedented accuracy.

Clear Skies Joe Slomka