2020, September 30: Jupiter, Saturn in Evening Sky

Bright Jupiter and dimmer Saturn appear in the southern sky after sunset on September 30, 2020.

by Jeffrey L. Hunt

As the sky darkens, look low in the southern sky for bright Jupiter and dimmer Saturn.  They look like overly bright stars. Saturn is to Jupiter’s upper left.

Both planets are gradually moving eastward compared to the starry background.  While they rise in the east and set in the west, they gradually move eastward compared to the stars.

Three stars are identified in the photo above:  Pi Sagittarii (π Sgr on the photo), 50 Sagittarii (50 Sgr) and 56 Sagittarii (56 Sgr).

The planets are moving in front of the stars of eastern Sagittarius.  These dimmer stars are identified by Greek letters and numbers, along with the genitive form of Sagittarius, and its shorter form (Sgr).

During the next several weeks, watch the planets move eastward – to the left on the photo. A binocular is helpful to see the planets with the stars.  Jupiter moves away from π Sgr and toward dim 50 Sgr.  Eventually, Jupiter passes that star as well and begins to close in on Saturn for their Great Conjunction on December 21, 2020.

For more about the Great Conjunction, read our feature article. This is the closest Jupiter – Saturn conjunction since 1623.

For the next several weeks, Saturn slowly moves away from 56 Sgr.

The motion is slow-moving and the anticipatory approach of Jupiter toward Saturn has been occurring since they emerged from the sun’s glare in the morning sky last winter.

Jupiter is now closing in on the Ringed Wonder.

Read more about the planets during October.