Phases of Moon is a GNOME Shell extension that betters earlier moon tracking add-ons by not just stating the lunar phase, but showing it.
Clicking on its panel icon shows a large illuminated moon synced to the current phase, and details on when the next lunar phase is due.
I took a look at the Luna extension earlier this year, a similarly-purposed applet the astronomically minded will appreciate. Alas, it’s been having issues of late.
Phases of Moon is a solid alternative, and unlike desktop apps or a websites that can tell you the same info but requires you to switch from what you’re doing, Phases of Moon lives in your top bar, always visible (bar rare occasions – a bit like like the real deal).
The icon in the panel relays the current lunar phase directly, but the popup shows the phase name, illumination percentage, the age of the active phase, and a countdown (in days, hours and minutes) until the next lunar phase or event.
Many calculations are handled locally on your machine but Phases of the Moon also pulls in data from Starwalk, including the main moon image. If you click on the info in the pop up it takes you to a detailed lunar calendar on the Starwalk website.
A small set of options are provided, letting you pick a style of moon graphic (normal or inverted for light mode), pick a preferred panel position and set its index position to control precisely where it sits amongst other top bar icons.
Worth installing? As a humbling reminder that a ball of rock floating in space can stick to a schedule better than I can — sure! Perfect for night photographers, space geeks, the spiritually-minded and (of course) werewolf hunters.
Source code is on GitHub, but it’s easier to install it from GNOME Extensions (see below). It supports GNOME 46, 47, 48 and 49, which means if you run Ubuntu 24.04 LTS or later, you’re good to go.
Get Phases of Moon on GNOME Extensions