The opposition of Saturn on Friday, June 3, will be the best day of the year to get an exceptional glimpse of the gas giant with or without a telescope.
This event is called an "opposition" simply because Saturn will be directly opposite the sun in orbit. It's special for two reasons.
- When celestial objects are directly opposite the sun, they appear brighter in the sky than normal.
- Saturn will also be at its closest approach to Earth, which means it will appear slightly larger in the sky than usual, according to NASA.
Saturn is the farthest planet you can see with the naked eye. At 840 million miles away, you could fit nearly 1,000 suns in between it and Earth. (The sun is about 109 times the diameter of Earth.)
Though it will be big and bright on Friday, Saturn won't dominate the sky. The biggest and brightest planet will actually be Mars, which was at opposition a few weeks ago and is currently just about as close as it gets to Earth. That Mars and Saturn are at opposition within a month is pure coincidence. Saturn returns to opposition every 54 weeks; Mars returns every 26 months.
You'll be able to find Saturn at opposition by locating Mars in the southeastern sky near the constellation Scorpius (it will be the ruddy bright object). Saturn will appear to the left of Mars in the sky, shining an untwinkling golden color.
The gas giant will be visible with the naked eye, but according to Space.com it will take a telescope with 25 times magnification to see its glorious rings. Space.com also notes that Saturn's famous rings will be pointed toward Earth, so they'll be particularly viewable with the right magnification.
If you're unable to go outside to gaze at the night sky, the astronomy live-streaming website Slooh.org will be hosting a live stream here.
Opposition also means Saturn's motions will mirror the sun's. "It’ll rise in the east at sunset, climb highest up at your local midnight, and set in the west at sunrise," the astronomy website Earthsky explains. You'll have all night to catch the opposition.
Since Earth, Mars, and Saturn are all nearly aligned, NASA's STEREO-A spacecraft — which normally takes pictures of the sun — was able to capture a photo of the three planets (plus the star Antares) in a single frame.
If you can't get outside Friday night, know that Mars and Saturn will stick around and still be visible for the next few weeks.