APOD: 2026 September 13 – Comet NEOWISE Rising over the Adriatic Sea

On September 13, 2026, an astronomy photograph of the day captured Comet NEOWISE rising over the Adriatic Sea, a sight that was particularly awe-inspiring for early risers. Four years prior, on July 8th, the comet, known as C/2020 F3 (NEOWISE), had graced the pre-dawn sky with its brilliance, earning a nickname as the Great Comet of 2020.

This celestial phenomenon, visible to the naked eye, made headlines and fascinated astronomers and sky enthusiasts alike. The featured photographer managed to document this rare event using a time-lapse video, compiling over 240 images taken over a span of 30 minutes. This video showcased the comet's ascent above the Adriatic Sea, framed against a backdrop of bright noctilucent clouds and distant stars.

Remarkably, Comet NEOWISE maintained an unexpectedly high brightness for more than a month, with its ion and dust tails believed to emanate from a nucleus approximately five kilometers in diameter. The APOD's main NASA site announced a transition, moving from apod.nasa.gov to science.nasa.gov/apod. Tomorrow's featured image will highlight open space.

The image and accompanying text were credited to Paolo Girotti, along with contributions from Robert Nemiroff, Jerry Bonnell, Cecilia Chirenti, and Keighley Rockcliffe, all part of a service provided by the ASD at NASA/GSFC, NASA Science Activation, and Michigan Tech. U.