Saturday, May 28
An hour before sunrise, the Moon and Uranus are just rising together in the eastern sky. Give them about 20 minutes and they’ll sit roughly 4° above the horizon, a ripe target for binoculars. The delicate waning crescent Moon is just 4 percent lit, with only its western limb (east on the sky) illuminated by sunlight. The planet Uranus, a dim magnitude 5.9 dot, sits just under 2° northeast of our satellite. Binoculars — or, better yet, a small scope — should bring it out if you’re quick about it, but make sure to put your observing tools away as sunrise approaches. The Moon will pass 0.3° due south of Uranus at 10 A.M. EDT.
Also readily visible in the eastern sky this morning are Mars and Jupiter, now 50' (0.8°) apart. Mars, glowing at magnitude 0.7, sits just southeast of brighter magnitude –2.2 Jupiter. Keep an eye on this pair: Mars passes 0.6° south of Jupiter at 8 P.M. EDT tonight and will still appear that close to the planet tomorrow morning. We’ll be back to take a look.
Sunrise: 5:34 A.M.
Sunset: 8:20 P.M.
Moonrise: 4:31 A.M.
Moonset: 6:51 P.M.
Moon Phase: Waning crescent (3%)
Sunday, May 29
Early risers on the East Coast of the U.S. can catch the opening moments of a stunning show as Ganymede’s large shadow moves onto Jupiter’s disk starting at 3:49 A.M. EDT. The shadow transit, which will last a little over three hours, is underway as the gas giant rises in locations farther west. Ganymede itself sits east of Jupiter’s disk, slowly creeping closer as the hours tick by. Observers in western locations can also watch Io, closing in from the west, disappear into Jupiter’s shadow around 4:20 A.M. CDT.
Once you’re done enjoying the king of the planets and his court, zoom out a bit to catch Mars, now some 35' (0.6°) south-southeast of Jupiter’s bright glow —well within a single field of view for a telescope. Compare the two planets’ diameters for some extra fun: Jupiter now spans 37", while Mars, though closer to Earth, is a mere 6" across.
The pair will still be close tomorrow morning as well, when Mars sits 48' (0.8°) southeast of Jupiter.
Sunrise: 5:35 A.M.
Sunset: 8:20 P.M.
Moonrise: 4:59 A.M.
Moonset: 7:54 P.M.
Moon Phase: Waning crescent (1%)
Monday, May 30
New Moon occurs at 7:30 A.M. EDT — so now is the time to hunt down some amazing deep-sky objects. Tonight, let’s set our sights on Coma Berenices, still high in the southwest after dark. You’ll find the constellation just east of Leo and north of Virgo.
Coma Berenices is home to the Coma Galaxy Cluster, also cataloged as Abell 1656. The cluster’s two brightest galaxies are 11th-magnitude NGC 4889 and 12th-magnitude NGC 4874. You’ll find them a little less than 3° due west of 4th-magnitude Beta (β) Comae Berenices. These two galaxies sit just 7' apart and are embedded within a larger area of about 4° that contains hundreds more galaxies, though of course, not all are visible. Other prominent members include two 12th-magnitude spirals, NGC 4911 and NGC 4921. These both sit within 20' of NGC 4889, to its east (NGC 4921) and southeast (NGC 4911).
Overall, the Coma Cluster contains some 1,000 galaxies, all of which sit more than 300 million light-years from Earth.
Sunrise: 5:34 A.M.
Sunset: 8:21 P.M.
Moonrise: 5:31 A.M.
Moonset: 8:55 P.M.
Moon Phase: New