- Does the moon calendar match my menstrual cycle?
- Not exactly, and it does not need to. A lunar month is about 29.5 days and a menstrual cycle is commonly 21 to 35 days, so the two drift against each other. We show them side by side as two rhythms you can read together, not as a claim that one controls the other.
- What time zone are these dates in?
- All phase moments are calculated and shown in UTC. Depending on where you live, a phase can land on the previous or next calendar day in your local time.
- How are the dates calculated?
- With the astronomy-engine library, which searches for the exact moments the Sun-Moon elongation reaches 0°, 90°, 180° and 270°, and for the moments of greatest eclipse. Nothing is looked up from a table, and nothing is sent to our servers.
- Why do eclipses come in pairs?
- An eclipse needs a new or full moon close to one of the Moon's nodes, where its tilted path crosses the Sun's. The Sun passes each node about every six months, and for a few weeks either side a new moon can make a solar eclipse and a full moon a lunar one. So eclipses arrive in 'seasons', usually a solar and a lunar eclipse about two weeks apart.
- Is anything stored about me?
- No. This page reads only today's date in your browser. There is no account, tracking or third-party analytics. Our host counts page views first-party and in aggregate.