Last night we finally cleared off after four solid days and nights of gray and rain. Sparkling low in the northwestern sky was a most welcome sight – Venus, Jupiter and Mercury. This week they will undergo to a series of remarkable gatherings in the early evening sky.
Venus leaped out immediately as the brightest of the trio. It stood 6 degrees above the horizon; that’s three fingers held horizontally at arm’s length. Jupiter jumped out next some 5 degrees to the upper left of Venus. Mercury, the dimmest of the the bunch, was very easy in binoculars but took a bit of concentration to see with the naked eye.
This jam has just begun. Watch over the coming nights as the three planets move closer together to form a series of ever-changing jeweled triangles. Tomorrow night Mercury and Venus will be closest (1.4 degrees); Mercury and Jupiter on Memorial Day (2.3 degrees) and Venus and Jupiter on May 28 (1 degree).
All you need to see them is an unobstructed view to the west-northwest. You can begin your search about 30 minutes after sunset; get an early start because the planets set about an hour later. Binoculars can prove most helpful in case the sky’s hazy or if you have difficulty finding Mercury.
As you can see from the nightly maps, Mercury moves upward from the western horizon to join Venus, passes it and then teams up with Jupiter. Mercury moves rapidly because it orbits the sun most closely. Venus is also moving up from the west but more slowly, so it essentially stays in the same spot. Jupiter meanwhile drops down toward the western horizon. Earth’s motion around the sun is much faster than Jupiter’s causing the sun to literally “get in the way” between our two planets. From our perspective, Jupiter will soon disappear in the solar glare and won’t be seen again until early July when it reappears in the morning sky.
Although the trio may appear close to one another in the sky, they’re millions of miles from each other and the Earth. We see them together because they lie along the same line of sight for the coming week.