Three planets – Jupiter, Mars and Saturn – pop out as darkness falls in June 2016. Jupiter, the brightest of the bunch, is found in the western half of the sky and lights up the night until midnight or later. Mars, only a touch fainter than Jupiter, shines above Saturn in the southeast sky at nightfall. Saturn comes closest to Earth for the year on June 3, less than four days after Mars’ closest approach to Earth on May 30. Mars and Saturn shine close to the supergiant red star Antares on the sky’s dome, painting a bright and colorful triangle on the blackboard of night. Not only are Mars and Saturn at their brightest and best in late May and early June, they’re out all night long. Mercury appears as a morning “star” before sunrise, though this morning showing of Mercury greatly favors the Southern Hemisphere. The brightest planet – Venus – is lost in the glare of sun in June. Follow the links below to learn more about the June planets.
Jupiter brightest “star” in June. Jupiter lights up the sky almost immediately after sunset on these June evenings. From mid-northern latitudes, the king planet shines in the southwest sky at nightfall. From the Southern Hemisphere, look in the northern sky as darkness falls.
For all of us, Jupiter sets in the west at or around midnight. It will remain a fine evening object throughout July and into August.
Jupiter is almost impossible to miss. It’s the fourth-brightest celestial object, after the sun, moon and Venus. But Venus is now lost in the glare of the sun, so Jupiter rules the nighttime on June evenings. Although Mars is not all that much fainter than Jupiter in early June, Jupiter and Mars are nowhere close together on the sky’s dome. As evening falls, Mars and Saturn sit rather low in the southeast sky, while Jupiter appears in the western half of sky. Most of all, Mars’ bloody-red color is dead giveaway of the red planet. Jupiter, on the other hand, shines bold white.
If you have binoculars (on a tripod) or a telescope, it’s fairly easy to see Jupiter’s four major moons, which look like pinpricks of light on or near the same plane. They are often called the Galilean moons to honor Galileo, who discovered these great Jovian moons in 1610. In their order from Jupiter, these moons are Io, Europa, Ganymede and Callisto.
These moons circle Jupiter around the Jovian equator. In cycles of six years, we view Jupiter’s equator edge-on. So, in 2015, we got to view a number of mutual events involving Jupiter’s moons through a high-powered telescope. Click here or here or here for more details.
Although Jupiter’s axial tilt is only 3o out of perpendicular relative to the ecliptic (Earth’s orbital plane), Jupiter’s axis will tilt enough toward the sun and Earth so that the farthest of these four moons, Callisto, will not pass in front of Jupiter or behind Jupiter for a period of about three years, starting in late 2016.
During this approximate 3-year period, Callisto will remain perpetually visible, alternately swinging above and below Jupiter from our earthly perspective.
Click here for a Jupiter moons almanac, courtesy of Sky & Telescope.
Mars was at its brightest at its opposition on May 22. Jupiter was at its brightest during its opposition on March 8. Mars and Jupiter will remain spectacularly bright in the June night sky, but, by the month’s end, you’ll notice the edge has gone off Mars’ brightness.
Here’s some really good news, though. Mars is near another planet on the sky’s dome, Saturn. Look for Mars and Saturn near Antares, the brightest star in the constellation Scorpius the Scorpion. They make a noticeable triangle on the sky’s dome.
Let the moon help guide your eye to Mars (and the bright star Spica) for several evenings, centered on June 15. Then watch for the moon to swing away from Spica and more closely with Mars on June 16 and June 17. Then by June 18, the moon will move away from Mars to pair up with Saturn.
Saturn, dusk until dawn, shines near Mars. Both Mars and Saturn are near a fainter object – still one of the sky’s brightest stars – Antares in the constellation Scorpius.
The ringed planet starts the month rising in the east around sunset. That’s because Saturn will be at opposition – opposite the sun in Earth’s sky – on June 3. At opposition, Saturn is rising in the east at sunset, and setting in the west at sunrise. At midnight, meanwhile, Saturn is highest up for the night. By the month’s end, Saturn will be coming up in the east roughly two hours before sunset, and will soar to its highest point for the night around 10 p.m. local time (11 p.m. local Daylight Saving Time).
Although Saturn shines on par with the sky’s brightest stars, its brilliance can’t match that of Mars. Look for Saturn near Mars all month long. These two worlds form a bright celestial triangle with the star Antares in the June night sky. Mars is brighter than Saturn, which in turn is brighter than Antares.
Mars will eventually catch up with Saturn on August 24, 2016, to present a conjunction of these two worlds in the August evening sky.
Watch for the moon to swing by Saturn for several days, centered on or near June 18.
Saturn, the farthest world that you can easily view with the eye alone, appears golden in color. It shines with a steady light. Binoculars don’t reveal Saturn’s gorgeous rings, by the way. For that, you need a small telescope. But binoculars will enhance Saturn’s golden color.
Saturn’s rings are inclined at a little more than 26o from edge-on in June 2016, exhibiting their northern face. Next year, in October 2017, the rings will open most widely, displaying a maximum inclination of 27o.
As with so much in space (and on Earth), the appearance of Saturn’s rings from Earth is cyclical. In the year 2025, the rings will appear edge-on as seen from Earth. After that, we’ll begin to see the south side of Saturn’s rings, to increase to a maximum inclination of 27o by May 2032.
Mercury in eastern predawn sky. Mercury transitioned from the evening to morning sky on May 9, 2016. Usually, you can’t see Mercury at this juncture because it swings to the north or south of the solar disk, and is lost in the sun’s glare. But this time around, some of you actually witnessed the planet Mercury passing directly in front of the sun on May 9, 2016.
For the Southern Hemisphere, the first couple of weeks in June will feature a grand time for catching Mercury before sunrise in the predawn sky. Mercury will reach its greatest western (morning) elongation on June 5, 2016. Look eastward, over the sunrise point on the horizon, starting 90 minutes or more before sunrise. Look for the waning crescent moon near Mercury in the predawn/dawn sky on June 2 and 3.
It’ll be more of a challenge to spot Mercury as a morning “star” at dawn from mid-northern latitudes. Look eastward about 60 to 45 minutes before sunrise. Binoculars could come in handy.
Venus, brightest planet, lost in the sunrise. From all over the world, Venus sinks closer to the glare of sunrise until Venus swings directly behind the sun on June 6, 2016, to transition from the morning to the evening sky. Venus probably won’t become visible in the western sky at dusk until July.
Exactly four years previous to Venus passing directly behind the sun on June 6, 2016, Venus swung directly in front of the sun on June 6, 2012, to present the last transit of Venus until December 11, 2117. See the photo above.
What do we mean by bright planet? By bright planet, we mean any solar system planet that is easily visible without an optical aid and that has been watched by our ancestors since time immemorial. In their outward order from the sun, the five bright planets are Mercury, Venus, Mars, Jupiter and Saturn. These planets actually do appear bright in our sky. They are typically as bright as – or brighter than – the brightest stars. Plus, these relatively nearby worlds tend to shine with a steadier light than the distant, twinkling stars. You can spot them, and come to know them as faithful friends, if you try.
Bottom line: In June 2016, Jupiter is the brightest starlike object up when the sun goes down. Saturn and the bright star Antares make a triangle with Mars on the sky’s dome. Mercury, the innermost planet, is in the morning sky all month long. Venus is behind the sun.
Bruce McClure has served as lead writer for EarthSky's popular Tonight pages since 2004. He's a sundial aficionado, whose love for the heavens has taken him to Lake Titicaca in Bolivia and sailing in the North Atlantic, where he earned his celestial navigation certificate through the School of Ocean Sailing and Navigation. He also writes and hosts public astronomy programs and planetarium programs in and around his home in upstate New York.