There’s a lot going on in the night sky this month, from the largest Supermoon of 2020, to a meteor shower, planetary line-ups, and more. Bookmark it!
All times are listed as Eastern Time for the Northern Hemisphere.
Take note that we sometimes will use angular degrees to define the separation between two objects, such as (for example) the Moon and a bright planet. Keep in mind that the width of your clenched fist, held at arm’s length, measures roughly 10°.
April 1—First Quarter Moon at 6:21 a.m. In this phase, the Moon looks like a half-Moon in the sky. One-half of the Moon is illuminated by direct sunlight while the illuminated part is increasing, on its way to becoming a full Moon.
April 1—Mercury during April is a morning object, not well viewed from mid-northern latitudes. Early in the month, as seen from latitude 40° north, this bright planet rises only ¾ hour before sunup. During the second half of the month it is lost deep in the dawn. Superior conjunction will occur on May 4th. First Quarter Moon at 2:57 p.m.
April 3 – Venus rules the western evening sky. For viewers living in mid-northern latitudes from April 7th through the 22nd, this dazzling planet does not set until the final half hour before midnight (daylight-saving time). Venus passes dramatically near the pretty Pleiades Star Cluster on the first few evenings of April. On this evening, Venus is just ¼° southeast of Alcyone, and ⅓° south of the Atlas-Pleione pair. Venus is about ¾° from the cluster’s center on the night before and a little over 1° the night after. Venus’s glare will practically overwhelm the cluster for naked-eye observers when it is closest, but binoculars and wide-field telescopes will show both planet and cluster beautifully. Only in eight year cycles can Venus come so near the Pleiades – and in our lifetime these conjunctions are getting ever closer. As Venus passes a little farther north, it will actually go right through the cluster in the years 2028, 2036, 2044 and 2052.
April 7 – Full Moon at 10:35 p.m. EDT. Since the Moon arrives at perigee, at a distance from Earth of 221,772 miles about 8½ hours earlier, this will be the biggest full Moon of the year; colloquially known as a “Supermoon.” We will also see a greater range of tides over the next few days. High tides will run higher than normal; low tides will be lower than normal. This is also the Paschal Full Moon – the first full Moon of spring – which sets the date for Easter. Easter falls on the first Sunday after the first full Moon of spring and in 2020 will be observed on the 12th.
April 10 – Venus reaches its greatest celestial latitude north of the ecliptic plane and passes 10° to the upper right of the orange 1st-magnitude star Aldebaran during this upcoming week.
April 14 – Last Quarter Moon at 6:56 p.m. In this phase, the Moon appears as a half Moon due to the direct sunlight, the illuminated part is decreasing toward the new Moon phase.
April 15– In this morning’s predawn sky, a wide triangle is formed by Jupiter, Saturn and the Moon. The Moon sits 3° below and slightly to the right of Saturn and 6° to the lower left of Jupiter. Saturn and Jupiter are separated by 5½°. By month’s end they’ll be slightly less than 5° apart and will fit comfortably within the field of view of standard 7-power binoculars. Jupiter remains a target for early risers. It’s highest and most observable in the southeast during dawn, shining brightly well to the left of the Teapot pattern in Sagittarius. The king of the planets is slowly drawing nearer to us on its way to opposition next July. During April this dazzling planet brightens slightly and increases somewhat in size as viewed in telescopes. Saturn, in Capricornus, starts the month just 1° north of Mars. The ringed planet rises around 3:40 a.m. local daylight time at the beginning of April, and at 1:50 a.m. by the end of the month. The best time to observe Saturn is just before the first light of dawn, when it will have climbed above the horizon.
April 16—This morning a slightly slimmer Moon visits Mars, passing 3½° below and to the left of that planet. Mars starts the month in Capricornus, sitting just 1° below Saturn. The two planets appear virtually the same in brightness, but contrast noticeably in color; Saturn shines a sedate yellow-white, while Mars glows an orange-red. Quickly, Mars races away to the east of Saturn as the month progresses. Have you noticed how much brighter it’s becoming? When the year opened Mars rose only a little later in the night than now, but it was one magnitude, or 2½ times fainter. If your daily routine rouses you from bed while the sky is still fairly dark, take a look out a southeast window each clear morning to watch the red planet swell noticeably in brightness during April.
April 16 – Also look for Lyrid meteor shower activity. These meteors are active from April 16 to the 25, peaking around April 22-23. These meteors have been observed for more than 2,600 years; Chinese records say “stars fell like rain” in the shower of 687 B.C. But in recent times the Lyrids have generally been weak. They have a brief maximum that lasts for less than a day, and even then only 10 to 20 Lyrids per hour may appear. In 1982, however, the hourly rate unexpectedly reached 90 for a single hour, and 180 to 300 for a few minutes. A brief outburst of 100 per hour was also seen in 1922. This unpredictability always makes the Lyrids a shower to watch. The radiant point of this shower lies between the brilliant blue-white star Vega and the so-called Keystone pattern of Hercules. This year’s peak activity is due around 2 a.m. EDT with the radiant soaring high in the eastern sky for most of North America.
April 22 – New Moon at 10:26 p.m. In this phase, the Moon is not illuminated by direct sunlight and is completely invisible to the naked eye.
April 26 – They are widely separated by 7°, but the two brightest objects in the night sky, the Moon and Venus still make for an eye-catching sight as they descend side-by-side in this evening’s west-northwest sky.
April 27 – Venus reaches the pinnacle of its great brilliance for 2020 this evening, also referred to as its “greatest illuminated extent”; a compromise between its increasing apparent size and the diminishing illuminated portion of its disk. Telescopes show its apparent diameter noticeably increasing in April while its phase thins from 47% to 25% lit. If you hope to see any subtle detail in Venus’s clouds, observe before the sky gets too dark and Venus dazzles with glare. This is an ideal month to view Venus in broad daylight through your telescope – or even with your naked eyes.
April 30 – First Quarter Moon at 4:38 p.m. In this phase, the Moon looks like a half-Moon in the sky. One-half of the Moon is illuminated by direct sunlight while the illuminated part is increasing, on its way to becoming a full Moon.
By Farmers’ Almanac Astronomer Joe Rao. This calendar is adapted from “Skylog,” a regular feature appearing in Natural History magazine written by Mr. Rao since 1995.