Above photo: First quarter moon as captured by Duke Marsh in Indiana. Thank you, Duke!
Tonight – April 30, 2020 – the moon is at or near its first quarter phase, as darkness falls around the world. At first quarter moon, the moon is 90 degrees east of the sun on the sky’s dome, and its disk is half-illuminated by sunshine. About one week from now – on May 7, 2020 – the moon will turn full when it’s 180 degrees from the sun in our sky, and its disk is totally illuminated by sunshine.
This first quarter moon presents the second of two April 2020 first quarter moons, with the first one falling on April 1, 2020. It’s the only time this year that two first quarter moons take place in a single calendar month, though the event probably won’t generate much fanfare. Later on this year, two full moons will occur in October 2020, and the second of these two full moons will be celebrated by many people around the world as a Blue Moon.
The second first quarter moon of April 2020 comes on April 30, 2020, at 20:38 UTC. In United States time zones, that gives the local clock time for the first quarter moon as 4:38 p.m. EDT, 3:38 p.m. CDT, 2:38 p.m. MDT and 1:38 p.m. PDT. Although the moon will be slightly past its first quarter phase as darkness falls over North America on April 30, you can still see the moon at the instant of its first quarter phase in a daytime sky.
Click on this Sunrise Sunset Calendar to find out the moon’s rising time, remembering to check the moonrise and moonset box.
This first quarter moon shines in front of the constellation Cancer the Crab, one of the faintest constellations of the zodiac. Because the first quarter moon is 90 degrees east of the sun on the sky’s dome, the first quarter moon shows you where the sun will be shining in front of the constellations of the zodiac some 3 months (or 1/4 year) from now: on or near July 30, 2020.
Click on Heavens-Above to know which constellation of the zodiac backdrops the moon.
The sun will pass in front of the constellation Cancer from July 20 to August 10, 2020. Of course, the constellation Cancer will then be invisible because it’ll be rising and setting with the sun, and will be lost in the solar glare.
Bottom line: Tonight – April 30, 2020 – enjoy the second of two April first quarter moons, as it lights up Cancer the Crab, one of the faintest constellations of the zodiac.
Bruce McClure has served as lead writer for EarthSky's popular Tonight pages since 2004. He's a sundial aficionado, whose love for the heavens has taken him to Lake Titicaca in Bolivia and sailing in the North Atlantic, where he earned his celestial navigation certificate through the School of Ocean Sailing and Navigation. He also writes and hosts public astronomy programs and planetarium programs in and around his home in upstate New York.