Sky This Week is brought to you in part by Celestron.
Friday, June 27
The Moon passes 3° north of Mercury at 2 A.M. EDT. By evening the two are visible in the western sky, roughly 8° high an hour after sunset. The crescent Moon lies 9.5° east (to the upper left) of magnitude 0.2 Mercury, which is closer to the horizon. Between them is the gorgeous Beehive open cluster (M44), whose scattered stars shine collectively at 4th magnitude. Covering nearly 100’ on the sky, this cluster is best taken in visually or at low magnification, such as with binoculars or your telescope’s finder scope.
Under higher magnification (such as through any telescope), Mercury’s disk appears 7” wide and is 51 percent illuminated. Tomorrow the planet will appear exactly 50 percent lit, so make sure to come back and take another look then. And later this week, Mercury will skim just south of the Beehive, so we’ll be back then to enjoy the view as well.
Tonight Mercury stands directly to the left of and mostly in line with the bright stars Castor and Pollux, the heads of Gemini the Twins. Pollux is the closer of the two to Mercury; its light should appear slightly yellower than blue-white Castor’s, to Pollux’s right.
If you follow a line from Mercury to the Moon farther to the upper left, you’ll first spot the magnitude 1.4 star Regulus, the heart of Leo the Lion. To its upper left is ruddy Mars, shining at the same magnitude.
Sunrise: 5:34 A.M.
Sunset: 8:33 P.M.
Moonrise: 7:43 A.M.
Moonset: 10:48 P.M.
Moon Phase: Waxing crescent (7%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 12 P.M. local time from the same location.
Saturday, June 28
Venus is a bright morning star dominating the predawn sky at magnitude –4.2. Today, the blazing planet moves from Aries into Taurus, standing at a point just less than 10° southwest of the Pleiades star cluster. The Pleiades, also cataloged as M45, is one of the easiest-to-spot clusters in the sky, shining at magnitude 1.6 and spanning some 110’.
About 4.3° south of the Pleiades is Uranus. Glowing a faint magnitude 5.8, it’s just at the edge of naked-eye visibility under exquisite conditions and is best seen with binoculars or a telescope. The ice giant spans just 3”, but that should still be enough to appear as a small but noticeable disk, rather than a pinpoint like a star.
Turn that telescope back on Venus and you’ll see a much larger disk 18” across. As an inferior planet closer to the Sun than Earth, Venus also appears to go through phases and now presents a 63-percent-lit gibbous.
Venus will continue trekking eastward deeper into Taurus this week, passing 2° from Uranus on July 3 and offering a bright signpost to help you find the planet at the end of the week.
Mercury, which also appears to go through phases, reaches 50 percent lit today. You can catch the small planet in the western sky tonight, setting a little over 90 minutes after the Sun. The waxing crescent Moon has moved into Leo, with the Lion’s alpha star Regulus between it and Mars, to the Moon’s upper left.
Sunrise: 5:34 A.M.
Sunset: 8:33 P.M.
Moonrise: 8:55 A.M.
Moonset: 11:17 P.M.
Moon Phase: Waxing crescent (13%)
Sunday, June 29
Saturn passes 1° south of Neptune at 4 A.M. EDT. The pair of planets rises shortly after midnight and is best seen in the few hours before dawn, standing some 35° high in the southeast around 4 A.M. local daylight time.
Saturn, at magnitude 1.0, is readily visible to the naked eye, hanging below the Circlet asterism in a relatively sparse region of southern Pisces. Neptune, at magnitude 7.8, cannot be seen without optical aid. With the two planets so close, both will appear within the field of view of binoculars or any telescope, with the tiny, bluish disk of Neptune 1° due north of Saturn.
Telescopes will also show Saturn’s lovely ring system, stretching 40” across and tilted about 3.6° to our line of sight. The planet’s largest and brightest moon, mid-8th-magnitude Titan, lies just under 3’ east of the planet tonight. In a few days’ time Titan’s shadow will transit the disk of Saturn, so make sure to keep reading for more details on how to observe this relatively rare event.
In the evening sky, the Moon passes 0.2° north of Mars at 9 P.M. EDT. The pair is visible for about three hours after sunset, slowly sinking in the west. The Moon is now nearly one-quarter lit and, thanks to its proximity, movies noticeably in the sky in the few hours it is visible. Check on the pair once an hour until they disappear beneath the horizon and you’ll likely catch the motion of the Moon as it slides eastward, from Mars’ lower right to its upper left. Although it’s a near miss for most of the world, some regions in western Africa will see the Moon pass in front of Mars in an occultation.
Sunrise: 5:34 A.M.
Sunset: 8:33 P.M.
Moonrise: 10:04 A.M.
Moonset: 11:41 P.M.
Moon Phase: Waxing crescent (21%)
Monday, June 30
Uranus now stands 5° northeast of Venus in the early-morning sky, putting the planets roughly in a horizontal line above the horizon. An hour before sunrise, they are roughly 16° high in the east, standing to the lower right of the Pleiades. If you first center bright Venus in a pair of binoculars, move the optics slightly to put it at the right edge of your field of view. Magnitude 5.8 Uranus should then be near the left edge of the field of view.
Venus will continue moving and close in further on Uranus in a few days, coming within 2° of the ice giant and offering an even better view.
Meanwhile, in the evening sky, Mercury is quickly closing in on the Beehive Cluster. The small planet stands less than 3° from the gaggle of young stars this evening. If you’re quick and have a clear western horizon, you can capture a view of both through binoculars an hour after sunset, when they are roughly 6° high. The higher magnification (and smaller field of view) of a telescope won’t yet show both objects together, but that will change in just two days’ time, on July 2. If you look through a telescope at Mercury tonight, you’ll notice it is quickly waning, now 46 percent lit. It has also faded slightly, shining at magnitude 0.3.
Sunrise: 5:35 A.M.
Sunset: 8:33 P.M.
Moonrise: 11:09 A.M.
Moonset: —
Moon Phase: Waxing crescent (30%)
Tuesday, July 1
Visible in the early-morning sky today, Saturn’s two-toned moon Iapetus reaches superior conjunction just 1.4′ due south of Saturn. The proximity makes the now-11th-magnitude moon easier to find, as it spends much of its time far east or west of Saturn, several arcminutes from the planet.
Try your luck about two hours before sunrise, while the sky is still dark and the dim moon will be easiest to see against the background. At that time, 1st-magnitude Saturn stands some 30° high in the southeast, easy to find in southern Pisces below the Circlet asterism. Center your scope on the ringed planet to find Iapetus less than 2’ south of the disk; brighter Titan, shining around 8th magnitude, is roughly the same distance east of the planet. Observers with larger scopes may also catch Enceladus, around 12th magnitude, just northeast of the planet’s equator, north of the rings. This moon can be difficult to see because of its proximity to the bright rings, but since they’re tipped such that they appear relatively thin, you may have better luck. Enceladus is heading behind the planet, however, and disappears shortly before 5 A.M. EDT. Meanwhile, 10th-magnitude Tethys reappears from occultation behind Saturn’s southeastern limb around 4:35 A.M. EDT — see if you’re able to catch the moment it winks back into view.
In the evening sky, Mars has moved to stand 8° east of Regulus in Leo. The Red Planet is now 22° high an hour after sunset, still offering decent views — but our time is limited. Mars is headed for solar conjunction early next year, so its visibility will only diminish through the rest of 2025.
The Moon has been trekking through the evening sky as well as waxing toward First Quarter phase, which it reaches tomorrow afternoon. Our satellite has now moved into Virgo and can be found some 24° east of Mars.
Sunrise: 5:35 A.M.
Sunset: 8:33 P.M.
Moonrise: 12:11 P.M.
Moonset: 12:02 A.M.
Moon Phase: Waxing crescent (39%)
Wednesday, July 2
Titan’s shadow transits the northern hemisphere of Saturn this morning beginning around 3:30 A.M. EDT. It’s definitely worth getting up early to catch this event if you can — we won’t get shadow transits much longer this year as the angle at which we’re viewing the Saturn system changes.
Saturn remains in the same spot in Pisces, visible to the naked eye as a 1st-magnitude light below the Circlet asterism. Center the ringed world in your telescope shortly before 3:30 A.M. EDT to make sure you’re ready for the moment Titan’s shadow appears at the eastern limb, north of the rings. Note that Titan itself is some 20” from the limb, casting its shadow on Saturn’s cloud tops from afar. It takes almost three hours for the shadow to reach midway across the planet, as the Sun is rising in the Midwest (and it’s already daylight along the East Coast). The shadow takes just over two and a half hours more to reach the northwestern limb, disappearing after day has broken across the continental U.S.
Follow the shadow as long as you can from your location, but take care to put away any optics at least several minutes before the Sun is due to rise from your location, which may differ from the time given here.
First Quarter Moon occurs at 3:30 P.M. EDT. Visible by early afternoon, the Moon hangs nearly 40° high in the south by sunset, now about 9.7° west of the bright star Spica in Virgo.
In the west after sunset, Mercury is finally buzzing the Beehive Cluster (M44). Mercury is now magnitude 0.4 and shows off a 43-percent-lit crescent through a telescope. Tonight the planet is 1° southwest of the center of the Beehive, passing through the cluster’s outskirts. Located in the center of Cancer, M44 covers an area of sky with a radius slightly more than three Full Moons placed side by side. That’s partly because the Beehive is relatively close to Earth, just under 600 light-years away.
It’s a lovely pairing that can be enjoyed through any telescope at low power, as well as through binoculars or even with the naked eye once the sky grows dark enough. Astrophotographers will definitely want to catch the sight, possibly with a lovely landscape beneath.
Sunrise: 5:36 A.M.
Sunset: 8:32 P.M.
Moonrise: 1:12 P.M.
Moonset: 12:21 A.M.
Moon Phase: Waxing crescent (49%)
Thursday, July 3
Venus passes 2° due south of Uranus at 9 P.M. EDT, with the planets visible in the predawn sky tomorrow. We’ll catch up with them then.
Earth’s year-long orbit around the Sun is almost — but not quite — circular. Our planet reaches aphelion, the farthest point in our orbit from the Sun, today at 4 P.M. EDT. At that time, Earth will be 94.5 million miles (152 million kilometers) from the Sun.
The Moon now passes 0.8° south of Spica at 6 P.M. EDT, with the pairing visible as evening twilight falls. (As with Mars earlier this week, some parts of the world will see Spica disappear behind the Moon in an occultation — this time, southern South America will get that view.)
By 9:30 P.M. local daylight time, the Moon sits to the lower left of Spica in the southwest. The star, which glows at magnitude 1.0, is an incredibly hot, massive star more than 10 times the mass of our Sun, shining with a piercing blue-white light that’s lovely through binoculars or any telescope. Take some time to enjoy the Moon under magnification as well, skimming along the terminator delineating lunar night from day, now centered on the nearside at First Quarter.
Sunrise: 5:36 A.M.
Sunset: 8:32 P.M.
Moonrise: 2:12 P.M.
Moonset: 12:41 A.M.
Moon Phase: Waxing gibbous (59%)
Friday, July 4
Mercury reaches its greatest eastern elongation from the Sun, standing 26° from our star at 1 A.M. EDT. We’ll take a look this evening but first, the predawn sky is the time to catch Venus and Uranus close together in Taurus.
You absolutely can’t miss Venus in the east in the hour or two before dawn, blazing at magnitude –4.1 in western Taurus to the lower right of the Pleiades. It’s the brightest point of light in the sky.
If you draw an imaginary line between the Pleiades and Venus, Uranus now sits about two-thirds of the way along that line, closer to Venus. If you center Venus in binoculars this morning, Uranus should appear well within the field of view, standing to the bright planet’s upper left. Depending on the field of view of your telescope under low magnification, you might also be able to capture both planets in your eyepiece, or try viewing them together in your finder scope. (Note the planets’ orientation may not be the same through a telescope as through binoculars, as the image may be flipped or rotated.)
Uranus, at magnitude 5.8, will look like a dim, “flat” star. Telescopic magnification will show it is not a pinpoint of light but a small disk 3” wide, with a green-gray hue. Although Uranus is physically much larger than Venus, the latter appears nearly six times as wide because of its much closer proximity to Earth. Venus is just 88.3 million miles (142 million km) away, while Uranus is some 1.9 billion miles (3.03 billion km) from us.
Evening observers, Mercury is your target once more, sinking in the west after sunset. As soon as the sky grows dark, look for the magnitude 0.5 planet still in central Cancer and now just over 2° southeast of the Beehive Cluster. This evening, Mercury also sits less than half a degree south of the 4th-magnitude star Delta (δ) Cancri, which will appear close to the planet if you pick it up through binoculars or a telescope. Through the latter, you’ll see that Mercury’s phase has waned further over the past few days, now presenting a 40-percent-lit crescent.
Mercury’s altitude will now begin sinking night by night when viewed at the same time, so we’ll only have short time more to catch it in the evening sky before it gets too close to the Sun for viewing.
The Moon is at apogee, the farthest point from Earth in its orbit, at 10:29 P.M. EDT. Our satellite will then be 251,423 miles (404,626 km) from Earth.
Sunrise: 5:37 A.M.
Sunset: 8:32 P.M.
Moonrise: 3:13 P.M.
Moonset: 1:02 A.M.
Moon Phase: Waxing gibbous (68%)
