Enjoy this photo of Saturn from one of the finest instruments on the planet. Or off the planet. The Hubble Space Telescope orbits 335 miles (540 km) above the Earth’s surface and completes one revolution in about 97 minutes. The color and detail in the photo are stunning. Be sure to click on the image for a large, monitor-filling version.
On June 6, a month before Saturn reached opposition — its closest to Earth this year — Hubble was used to observe and photograph the planet, which presents its rings at near maximum tilt this year. Jupiter, Uranus and Neptune all have rings but they’re no match for Saturn’s, the largest, brightest and most spectacular in the solar system. The north face of the rings and north polar region are tipped into view. The white spot and wisps at the edge of the polar region comprise a storm, now slowly disintegrating, that’s been active the past couple months. While it shows up well in the Hubble photo and in images taken by amateur astronomers, it’s too small to eyeball in a typical telescope.
Also visible is the hexagonal pattern to the dark clouds around the north pole. The “polar hexagon” is a stable and persistent wind feature that was discovered by the Voyager 1 space probe in 1981. The sides of the hexagon each measure about 8,600 miles (13,800 km) long or about 700 miles wider than the diameter of the Earth. Scientists were able to re-create the hexagon by spinning a liquid in a tank at one speed in its center and another speed around its circumference. It’s thought that strong changes in wind speed with changing latitude at Saturn may give rise to the pattern.
Hubble also managed to capture images of six of Saturn’s 62 currently known moons: Dione, Enceladus, Tethys, Janus, Epimetheus, and Mimas. The first three are visible in 6-inch and larger telescopes right from your backyard.
Saturn is currently due south in the lower third of the sky at twilight gives way to night. It shines from Sagittarius the Archer right in the middle of the Milky Way. We’re currently in a perfect stretch of time to bring out a telescope for a look. No scope? Check online to see if there’s an astronomy club in your area. Contact them and ask when their next public observing session will be held.