Skywatch Line for Monday (Earth Day) and Tuesday April 22nd and 23rd, written by Joe Slomka

This is the Dudley Observatory’s Skywatch Line for Monday (Earth Day) and Tuesday April 22nd and 23rd, written by Joe Slomka.

The Sun sets at 7:46 PM; night falls at 9:33. Dawn begins at 4:14 AM and ends with Sunrise at 6:01.

Southeast Virgo hosts the Moon on both nights. Monday’s Moon sets at 5:25 AM and rises at 6:43 PM. By 9 PM it is 21° high, appears 29 arc-minutes in size, 99% illuminated and sets at 5:43 AM on Tuesday’s morning. Tuesday’s Full Moon rises at 7:47 PM, 10° high, 30 arc-minutes and sets at 6:04 AM, Wednesday.

Jupiter and Uranus share northwestern Aries and will be soon hidden by the Sun. Jupiter glistens with minus 2nd magnitude, 33 arc-seconds and 3° high. Uranus is literally next to Jupiter, shines with 5th magnitude, 3 arc-seconds and 2° high. Both set at 9:16 PM.

The pre-dawn sky is quite active. Saturn and Mars share eastern Aquarius. Saturn rises first at 4:28 AM, 1st magnitude, 16 arc-seconds and is 6° high at 5 AM. Mars is next, rising at 4:43 AM, also 1st magnitude, 4 arc-seconds and 4° high. Neptune brings up the rear, rising at 4:54 AM, glowing with 8 magnitude, 2 arc-seconds and 2° high. They all set during daytime.

The annual Lyrid meteor shower reaches its peak at 3 AM, Monday in the northeast, and produces 18 meteors per hour. However, this year, the brilliant Moon makes observation difficult.

The annual Lyrid meteor shower, like most meteor showers, are litter left over from passing comets; as these specs of dust enter our atmosphere, they burn up in a fiery trail. This meteor shower has been continuously observed for over 2600 years. The shower is associated with Comet Thatcher and appears to originate near the bright star Vega in the constellation Lyra. Observers are advised to look between late evening and Dawn. However, the brilliant Moon will interfere.

The discovery of Comet Thatcher is very interesting. Alfred E. Thatcher lived in New York City. On April 5th 1861, he discovered the comet (officially C/1861 G1), shining with 7th magnitude. He used a 4.5inch refracting telescope, magnified 30 times. Over the next few weeks, the comet approaches the Sun and Earth and brightens before disappearing in June. Comet Thatcher will return in 2278. This discovery occurred before New York City became awash in light pollution