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April 5: Your last glimpse of Comet Wierzchoś?
The Moon passes 0.6° south of Antares at 4 P.M. EDT on April 6, with the two visible together in the early-morning sky prior to the passage.
Look south around 5 A.M. local daylight time to find the waning Moon already embedded within Scorpius the Scorpion’s front claws. It lies just to the lower right (west) of Antares, also cataloged as Alpha Scorpii and a lovely red giant star whose color you can admire through binoculars or a telescope. That color is what has gained it its name — it is often called the Rival of Mars because it looks to so many observers like the Red Planet.
Shining at magnitude 1.1, Antares is an M-class star that is much more massive than the Sun, weighing in at some 15 to 18 times more, according to the late stellar expert Jim Kaler. Although it’s now much cooler than the Sun, Antares shines about 10,000 times brighter than our star, albeit from some 550 light-years away.
Antares is also a known double star, with a magnitude 5.5 companion visible just 3” away. Although this companion is a hot, blue-white star, it is one of a few stars that sometimes appears green to observers, thanks to the way human eyes see it in contrast with nearby ruddy Antares.
Sunrise: 6:36 A.M.
Sunset: 7:30 P.M.
Moonrise: —
Moonset: 8:37 A.M.
Moon Phase: Waning gibbous (78%)
*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.
Glowing more brightly than expected, Comet C/2025 R3 (PanSTARRS) is flying near the Great Square of Pegasus early in the morning. Even with a waning gibbous Moon in the sky, let’s try for it on April 7.
Recently reported around 6th magnitude, this comet should be within the range of most amateur scopes. It’s expected to brighten at least two more magnitudes this month, although comets don’t always do as astronomers predict.
Rising around 3:40 A.M. local daylight time, give PanSTARRS an hour or so to climb above the horizon before searching it out. Around 4:45 A.M. local daylight time, it’s reached an altitude of 10° in the eastern sky. It lies close to the western side of the Great Square of Pegasus, between the stars Alpha (α) and Beta (β) Pegasi, also known as Markab and Scheat, respectively. From Markab, which is lower in the sky than Scheat, shift your scope 5° north-northwest to land on the comet.
