Posted by Mistress of the Myst
The Sky This Week for July 7 to July 9
Pluto’s peak appearance, a globular cluster in Ophiuchus, and other amazing things to look for in the sky this week.
By Richard Talcott
Friday, July 7
This week offers observers their first peek of Mercury during its current evening apparition. The innermost planet stands 6° high in the west-northwest a half-hour after sunset tonight. Although Mercury glows brightly, at magnitude –0.6, you might need binoculars to spot it initially against the twilight glow. A telescope reveals the planet’s disk, which spans 5.6″ and appears 80 percent lit.
Saturday, July 8
Full Moon officially arrives at 12:07 a.m. EDT tomorrow morning, but it looks completely illuminated all night. It appears low in the southeast as the Sun sets and climbs highest in the south around 1 a.m. local daylight time. The Full Moon resides among the background stars of Sagittarius the Archer throughout the night.
Sunday, July 9
Tonight marks the peak of Pluto’s 2017 appearance. The distant world reaches opposition, which means it lies opposite the Sun in our sky and remains visible all night. It glows dimly at 14th magnitude, however, so you’ll need an 8-inch or larger telescope with good optics to spot it visually. Pluto currently lies in northeastern Sagittarius, some 1.8° east-southeast of 3rd-magnitude Pi (p) Sagittarii. See “In pursuit of Pluto” in the July Astronomy for complete details on finding this world.