June ’25 – Rick’s Picks

Transient Events That Can Give Us a Good Enough Reason to Get Outside and Do a Little Observing

All month: Mercury returns to the sunset sky as Jupiter departs, leaving Mars as the only planet on the evening stage, while the morning sky is populated by Venus, Saturn, Neptune and (later in the month) Uranus. As June begins, Jupiter shines at mag -1.9 but sets just 75 minutes after the Sun, remaining less than 7° above the horizon at 8:50 pm (a half hour after sunset). It passes Mercury in a challenge view on the 7th, and is lost in the sunset glare by the 10th, on its way to solar conjunction on June 24. It will return as a morning target in July. Following its own conjunction on May 30, Mercury rises into the evening sky throughout June, becoming an easier sunset catch as the month goes on: its disk grows from 5 to 7.5 arcseconds but dims from mag -1.5 to +0.2 during the month, as its illuminated portion shrinks from 92% to 48%. By month’s end, it sets 90 minutes after the Sun. Once Mercury dips below the horizon, the evening sky belongs to Mars, which sets around 12:45 am on June 1 and 11:30 pm on June 30, its 5 arcsecond disk fading slightly from mag +1.3 to +1.5 along the way. After a couple hours with no visible planets, Saturn and Neptune rise almost simultaneously, just before 2:20 am as June opens and before 12:30 am as it ends. Saturn grows and brightens a bit during the month, from 17 to 18 arcseconds and mag +1.1 to +1.0, with its rings now tilted 3.7° to our line of sight, exposing their south face. Neptune’s 2 arcsecond disk glows at mag 7.9 all month. Brilliant Venus is the next planet up, rising at 3:15 am on June 1 and 2:45 am on June 30, starting as a 24 arcsecond disk 50% illuminated and shining at mag -4.4, and ending as an 18 arcsecond disk 63% lit at mag -4.2. Uranus brings up the rear, starting the month lost in the morning glare, but rising 90 minutes before the Sun by June 15, when its 3 arcsecond mag 5.8 disk sits 5° above the horizon at 4:15 am (an hour before sunrise). Among the asteroids, 4 Vesta is no longer a naked eye target (even from a dark site), but it remains brighter than mag 7.0 and an easy catch in eastern Virgo. This month’s charts will lead you to it.

June 1: Venus rises in this morning’s sky at 50% illumination – but it might not appear to be exactly half lit (or “at dichotomy”) for several days due to the Schröter effect, which makes dichotomy appear later when Venus (or Mercury) is in a morning apparition, and earlier in evening ones. Tonight, mag 1.4 Regulus (Alpha [] Leonis) crosses the sky less than 1° below and slightly left of the fat crescent Moon. The pair get as close as 32 arcminutes apart (at 11:20 pm CDT), as Mars watches their close dance from 8° to the lower right.

June 5: tonight mag 1.0 Spica (Alpha [] Virginis) unsuccessfully pursues the gibbous Moon, starting out 5° behind its bright quarry and slowly getting closer, but never catching up.

June 6-8: Mercury barely pokes its nose above the sunset horizon as Jupiter sinks into the solar glare in three days of challenge observations. At 8:55 pm (30 minutes after sunset) on the 6th, mag -1.9 Jupiter, 32” wide, sits 3½° above the horizon and 3½° left of the spot where the Sun went down, with the 5” disk of mag -1.5 Mercury 3.7° to its right and just 2½° above the horizon. At the same time on the 7th, Jupiter is 3° up and 3° left of the sunset spot, while Mercury has faded to mag -1.2 and sits 2.3° to the right of Jupiter and a smidgen higher. At

the same time on the 8th, Jupiter is 2½° up and 2½° left of where sunset happened, while Mercury (now at mag -1.1) is 1° to Jupiter’s right and 1½° higher in the sky. On all three nights, you’ll need binoculars to pick the planetary pair out of the gloaming. Give yourself a pat on the back if you succeed on any of the three!

June 9: the coquettish Moon, now nearly full, continues its fickle flirtations with mag 1 stars: tonight’s swain is mag 0.8-1.2 variable Antares (Alpha [] Scorpii), who rises 3½° behind the Moon before sunset and trails behind all night, until the pair set around 4 am CDT.

June 16: night owls and early risers have a rare opportunity this morning as the shadow of Saturn’s largest moon, Titan, crosses the face of the planet beginning at 3:21 am CDT. Shadow transits of Saturn’s moons are visible from Earth only near ring plane crossing, when the two planets lie in nearly the same plane. Titan transits can be seen in apertures as small as 6”, but you’ll need high power (over 200x) and excellent sky conditions to spot the tiny dark dot slowly crossing Saturn’s face (the entire passage will take over 5½ hours, ending well after sunrise). This will be the third of nine visible Titan transits in this series, and more challenging than those that come during the next few months, so if you don’t succeed this time, don’t give up!

June 16-18: turn your binoculars towards the western sky between 9 and 11 pm on any of these three nights to see a close and colorful pairing of ruddy Mars and blue-white mag 1.4 star Regulus (Alpha [] Leonis). The two appear to be less than a degree apart, as if they were an orange and bluish double star. Use the old trick of slightly defocusing your binos to spread the pair’s colors across a larger area and make the contrast easier to appreciate.

June 20: summer is icumen in, as a medieval troubadour might put it, when the Sun hits its northernmost stop at the solstice, 9:42 pm CDT, and bounces off on a southward journey for the next six months.

June 25-26: new Moon arrives on the 25th at 5:32 am CDT, making for a challenging binocular observation at 9:01 that evening (a half hour after sunset), when a paper-thin crescent, 0.6% illuminated, will sit 2½° above the WNW horizon, just above the spot where the Sun went down. You’ll have to find it quickly, before it sets just 17 minutes later. If you miss it then, try again at the same time on the 26th, when the Moon will be 40 hours old, 3.5% illuminated, and 4° to the right of mag +0.0 Mercury. You’ll have plenty of time to spot them both before they set together just after 10 pm. See if you can also pick out mag 1.2 Pollux [Beta [] Geminorum), 5° right of the crescent, and mag 1.9 Castor (Alpha [] Gem), 5° farther to the right.

June 27: elusive Neptune is an easy catch this morning, as it rises with much easier-to-find Saturn around 12:30 am CDT and stays near it as the pair cross the morning sky. Although the ringed planet is 500 times as bright, mag 7.9 Neptune should be visible in binoculars as a distinctly blue target 1° to the upper right. If you miss it this morning, you can try again, since the two planets will remain within a degree of each other until late July.

June 29: the 5 day old crescent Moon crosses the sky with tiny Mars practically touching it. The pair set together around 11:30 pm CDT. Can you spot Mars in binoculars or a telescope before sunset, using the Moon as a marker? Look for the red planet 1° left of the crescent at 5:30, 20 arcminutes above it at 8:30, and a half-degree above right by 9:30 pm.

June 30: at 9:01 pm CDT (a half hour after sunset), mag +0.4 Mercury sits 10° above the WNW horizon, 15° left of the spot where the Sun went down. You’ll need either binoculars or a wide-field telescope to include the stars of The Beehive (M44) in the view, 3° above left of the little planet.

Rick Gering / June 2025