The best time to view Saturn is almost here: On Sept. 21, the ringed planet will reach opposition, meaning Earth will be positioned directly between Saturn and the sun. (In other words, it is on the opposite side of Earth as the sun.) At that moment, the sun, Earth and Saturn will form a straight line.
During opposition, Saturn will appear to be at its biggest and brightest because the planet will be at its closest point to Earth. Similar to a full moon, Saturn will seem to be fully illuminated by the sun’s rays because of its position relative to the sun. This event happens just once every 378 days, so you won’t want to miss this opportunity to see it.
When Saturn reaches opposition, viewing conditions will be ideal. On Sept. 21, the moon will be in its new phase, so moonlight won’t threaten to wash out objects in the night sky. And because Saturn will be directly opposite the sun, the planet will be visible all night, rising in the east around sunset and setting in the west around dawn local time, according to Earth Sky.
To make these viewing conditions even better, observe Saturn away from sources of artificial light, which can wash out objects in the night sky and make skywatching more difficult. You’ll also want to allow 15 to 30 minutes for your eyes to adjust to the dark before you begin your observations. If you must use a flashlight, choose red light instead of white light to preserve your night vision.
Saturn will appear at the bottom of the constellation Pisces. Because the ringed planet is quite bright, it’s easy to spot in the night sky. But if you need help locating Saturn, you can use a skywatching app like Stellarium.
The best way to view Saturn is through a pair of skywatching binoculars or a backyard telescope. Through skywatching equipment, you can observe Saturn’s stunning rings, which undergo a dramatic brightening known as the Seeliger effect.
Related: A ‘crescent sunrise’ solar eclipse is coming this weekend. Here’s where to see it.
When Saturn reaches opposition, the rings appear much brighter than normal because the direct sunlight reflects off the rings and eliminates shadows among the countless particles that make up Saturn’s rings, according to Astronomy Magazine. The Seeliger effect lasts a few days around the time Saturn reaches opposition.
Although the precise moment of opposition centers on Sept. 21, it takes Saturn a couple of weeks to approach and leave its position in the opposite part of the sky from the sun. So if you can’t see Saturn on the 21st, you still have some time to view the ringed planet at its biggest and brightest a day or two before and after that date.
Saturn happens to reach opposition this year on the same day that a partial solar eclipse will be visible from parts of Antarctica, Australia and New Zealand. The next day, Sept. 22, marks the autumn equinox in the Northern Hemisphere, when Earth’s seasons change and progressively longer nights for skywatching begin in the North.
