Have you seen Neptune?

All you need is a pair of binoculars–10X50s should do the trick. Planets are not much bothered by light pollution. The hard part is actually finding it! Sky and Telescope have published this chart.

Pallas and Neptune time exposure
I captured this image of Pisces’ Circlet asterism along with Pallas (magnitude 8.6) and Neptune (7.8) around 9:45 p.m. September 12, 2021. The two were 6.8° apart at the time and will remain near each other all fall. Details: 35-mm lens, f/2.8, 70-second exposure at ISO 800 with a tracking mount. Bob King

Neptune

Neptune September map
For the next couple of weeks you’ll find Neptune near a small triangle of ~6.5-magnitude stars (magnitudes shown) 5.8° south of Kappa (κ) Piscium in the Circlet of Pisces asterism. The planet’s position is shown through September 30th. For a complete path, get the September issue of Sky & Telescope magazine.

Slightly brighter at magnitude 7.8, it’s relatively easy to spot in a pair of 10×50 binoculars. On the night of September 23–24 the methane-blue planet passes just 1.6′ south of 6.3-magnitude HD 221148. Modest-aperture telescopes will show it as a tiny, aqua disk at a magnification of 100× or higher.

If you have a 10-inch or larger instrument be sure to look for its brightest and largest moon, Triton, which never strays far from the mothership. This season its distance ranges from 9.5″ to 17″. Use 200× or higher to separate the 13.5-magnitude speck from Neptune’s glare when it’s at or near greatest elongation. To pinpoint its position anytime, check out Sky & Telescope‘s Triton Tracker.