Each Monday I pick out the northern hemisphere’s celestial highlights (mid-northern latitudes) for the week ahead, but be sure to check my main feed for more in-depth articles on stargazing, astronomy, eclipses and more.
The Night Sky This Week: July 10-16, 2023
The skies are about as dark as they ever get, but since July in the northern hemisphere, true darkness is extremely limited. Luckily, it’s a perfect week to get to grips with the solar system, with the waning moon, and a bevy of planets together causing a series of pretty conjunctions and celestial tableaux.
Monday, July 10: Last Quarter Moon
Tonight our natural satellite in space reaches its Last Quarter phase, which means it rises after midnight and leaves the evening night sky free of its reflected light.
Tuesday and Wednesday, July 12 and 13: Manhattanhenge
This phenomenon sees the ever-moving sunset point neatly positioned between skyscrapers. That’s thanks to the grid pattern of Manhattan, which is lined-up to the cardinal points. It happens for two days in May and two days in July, every year. If you’re in town then look west on July 12 at 8:20 p.m. and July 13 at 8:21 p.m. (EDT), but before you do find out where to stand from this exhaustive guide on the website of the American Museum of Natural History.
Thursday, July 13: Crescent Moon And The Pleiades
A super-slim crescent moon about 18%-lit will display reflected “Earthlight” as it appears in the east a couple of hours before sunrise with the Pleiades open cluster 2º above it. Jupiter will also feature to the upper right.
Friday, July 14: Mercury Rising
The “Swift Planet” will be this evening visible in the west-northwest, though you’ll need to look low to the horizon in the twilight before its sinks out of sight. Use binoculars.
Saturday, July 15: The Old Moon In The New Moon’s Arms
This morning in the hour before sunrise a gorgeous 5.5%-lit crescent moon—at this point in its monthly orbit often called “The Old Moon In The New Moon’s Arms”—will shine in the east-northeast. To its upper left will be the bright star Capella while to the upper right will the Pleiades, then Jupiter.
Sunday, July 16: Venus and Regulus
Tonight after dark in the west you’ll see bright Venus—now sinking out of the summer sky—less than 2º from Regulus, the brightest star in the constellation Leo and about 79 light-years from the solar system.
Object Of The Week: Noctilucent Clouds
If you’re a stargazer living at 50º North or farther from the equator then July is the worst month of the year. It never truly gets dark, but there is an advantage. With the Sun never getting farther than about 6º below the horizon its light still strikes the upper atmosphere. Sometimes it catches noctilucent clouds—also called night-shining clouds and space clouds—which are the product of water droplets and dust freezing together as ice crystals. Visible as tenuous-looking tendrils in the twilight, they can have a ghostly appearance. July is peak time for noctilucent clouds, so have look to the north and northeastern sky before you retire for the night.
Times and dates given apply to mid-northern latitudes. For the most accurate location-specific information consult online planetariums like Stellarium and The Sky Live. Check planet-rise/planet-set, sunrise/sunset and moonrise/moonset times for where you are.
Wishing you clear skies and wide eyes.