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April 19: The Moon passes above the Pleiades
After passing south of Mars late on the 19th, Mercury passes 0.5° south of Saturn at 4 A.M. EDT this morning. Mars will later pass 1.3° north of Saturn at 2 P.M. EDT.
This trio of planets congregates in the early-morning sky today: Mercury, Mars, and Saturn all lie within a 2°-wide area before sunrise, not to be missed. However, observing them will be a bit challenging, as they currently rise only shortly before the Sun.
Some 30 minutes before sunrise, the trio is just 2° high in the east. The brightest of the three is Mercury at magnitude –0.2, so look for this world first. Saturn, which is next brightest at magnitude 0.9, is just 28’ north (to the upper left) of Mercury; both are visible in the same field of view with binoculars or a small scope, and you will likely need some form of optical aid to pick up the ringed planet. Mars, the faintest of the three at magnitude 1.2, is located just over a degree north (again, to the upper left) of the Saturn-Mercury pair. Most scopes should still be able to capture all three in the same field.
Remember, as always, to stop your search and put away any optics at least several minutes before sunrise from your location, which may differ from the time given below.
Sunrise: 6:14 A.M.
Sunset: 7:44 P.M.
Moonrise: 8:06 A.M.
Moonset: —
Moon Phase: Waxing crescent (18%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 10 P.M. local time from the same location.
Have you had a chance to spot Comet C/2025 R3 (PanSTARRS) yet? It’s sinking quickly toward the horizon in the Northern Hemisphere, so if you have clear skies on the morning of April 21, give it a try. Its visibility will only diminish from here, and quickly.
Standing only 2° above the eastern horizon an hour before sunrise, PanSTARRS remains a stunning and popular target for astroimagers and is just brighter than 5th magnitude. Now a few days past perihelion, its tail spans several degrees and its nucleus glows that bright, familiar cometary green, generated by diatomic carbon (C2).
PanSTARRS is now located in Pisces, to the lower left of the Great Square of Pegasus. The nearest bright star is Algenib (Gamma [γ] Pegasi), which glows at magnitude 2.8. From this star, scan 9.4° due east (to the lower left) to land on the comet. Although it’s technically bright enough to see with the naked eye, binoculars may be your best bet. You can also try taking a several-second exposure of the eastern sky with your smartphone to see if that picks it up as well. Follow the comet as long as you can while the sky brightens, but put away any optics before sunrise.
