This is the Dudley Observatory Skywatch Line for Monday and Tuesday, October 19th, and 20th, written by Joe Slomka.
The Sun sets at 6:06 PM; night falls at 7:40. Dawn begins at 5:40 AM and ends with the Sun rising at 7:15.
The Moon resides in the constellation Ophiuchus each night. Monday’s Moon rose in daylight and sets at 8:16 PM. The planet Mercury is tonight’s challenge object, because it is close to the Moon and sets at 6:47 PM. Observers are advised to avoid looking at the Sun. Monday’s Moon also shines above Antares, the main star in Scorpius. Tuesday’s Moon appears 34 arc-seconds in size, 24% illuminated and sets at 9:03 PM.
Sagittarius continues to show Jupiter, Pluto and Saturn. Jupiter rises at 2:19 PM, shines with minus 2nd magnitude, appears 38 arc-seconds, is best observed at 6:48 PM and sets at 11:17 PM. Tuesday, sky watchers can witness the Jovian moon Europa begin to crawl across the planet’ face at 7:14 PM, followed by its shadow at 9:49 PM, Europa exits at 10:02 PM. Pluto is found between Jupiter and Saturn, glowing with 14th magnitude, appears as a tiny dot, rises at 7:04 PM and sets at 11:32 PM.
Six degrees East of Jupiter, Saturn rises at 7:16 PM, shines with zero magnitude, appears about 17 arc-seconds and sets at 11:51 PM. Both Jupiter and Saturn are still worth observing, but are now daily setting earlier.
Neptune, in Aquarius, rises at 5:08 PM, shines with 7th magnitude but appears only 2 arc-seconds big; highest at 10:46 PM, it sets at 4:28 AM. Uranus, in Aries, rises at 7:01 PM, glows with 5th magnitude, appears 3 arc-seconds. Best seen at 1:58 AM it sets in daytime.
Mars, in Pisces, flashes with minus 2nd magnitude and appears 22 arc-seconds. Rising at 6:30 PM, it is best surveyed at 12:54 AM and sets in daytime. Now past Opposition, Mars starts to move away from Earth and appears slightly smaller and dimmer daily.
Venus brings up the rear, rising in Leo at 3:50 AM, blazing with minus 4th magnitude, almost 15 arc-seconds and 78% illuminated. Venus sets during daytime.
Pre-dawn observers on Tuesday and Wednesday nights may see meteors streaming from the area of Orion’s club. This is the annual Orionid meteor shower. Meteor showers result when Earth’s orbit crosses paths with debris from comets’ tails. The Orionids come from the most famous comet of them all – Comet Halley, which returns about every 76 years. Astronomers predict an average year for the Orionids. The shower’s peak is Wednesday. The constellation is high and the Moon sets before 10 PM. If observing conditions are good, one may see up to 15 meteors per hour. The observer needs no special equipment; he simply stares at the sky. Since this is Autumn, cold weather clothing and boots help avoid the chill.