Will it update itself?

Yes. It is a subscription, not an import. Google refreshes subscribed calendars about once a day; Apple on the schedule you choose; Outlook every few hours.

Why does Google Calendar not show it on my phone?

Subscriptions are added on the web version of Google Calendar; once added they sync to the phone app. Add it at calendar.google.com, then turn it on in the phone app's settings.

Does it cost anything?

No. It is the one piece of Rhythm meant to sit in a stranger's calendar for years.

Can I get the moons as a printed calendar?

The Store has a yearly moon calendar as a PDF, computed from the same engine, for the wall or the planner.

The calendar feed

Put the moon on your calendar

Subscribe once. Every new and full moon, solstice, equinox and cross-quarter day lands in your own calendar a year ahead, in your own time, with the source in every entry. It keeps itself up to date.

The feed address is https://rhythm-dailysky.app/moons.ics. Copy it, or use the buttons below.

Add to Google Calendar →Add to Apple Calendar →

Step by step

Google Calendar

On a computer, open calendar.google.com. The phone app cannot add subscriptions, but it shows them once added.
In the left column, next to Other calendars, press the plus sign and choose From URL.
Paste https://rhythm-dailysky.app/moons.ics and press Add calendar.
It appears within a minute as "Rhythm — Daily Sky". Google refreshes subscribed calendars about once a day.
On the phone, open the Google Calendar app, go to Settings, find the calendar under your account, and turn on sync.

iPhone, iPad and Mac

Tap Add to Apple Calendar above. The phone or Mac asks whether to subscribe; say yes.
Or by hand: Settings, Calendar, Accounts, Add Account, Other, Add Subscribed Calendar, and paste https://rhythm-dailysky.app/moons.ics.
In the subscription's settings you can choose how often it refreshes. Daily is plenty.

Outlook

In Outlook on the web, open the calendar and choose Add calendar.
Choose Subscribe from web, paste https://rhythm-dailysky.app/moons.ics, name it, and press Import.
Outlook refreshes subscriptions every few hours.

What is in it

A year of the sky, computed

Every new and full moon with the sign it falls in, the solstices and equinoxes, and the cross-quarter days, from a few weeks ago to a year ahead. Each entry is an hour long at the exact instant, so it shows as a moment and not a day, and is marked free so it never blocks your time. The description carries a line about what the moon is for, the source, and the link.

It is built from the same engine as the moon calendar and the app, so the three never disagree. Nothing about you is in it; it is the same calendar for everyone, shown in each person's own time.

Instants computed with astronomy-engine, which follows the NASA JPL ephemerides. Festivals follow the sources named in each entry.