The Moon
Where it is, what shape it is, when it changes sign, when it is nearest and furthest, and when it goes dark. Worked out in your browser for this minute, in your own time zone.
This lunation
One row for the month the Moon is currently in, from the new moon that began it to the day before the next. Each disc is drawn from the lit fraction worked out for that day rather than picked from a set of eight pictures, so a moon two days past full is drawn two days past full.
Where the Moon goes next
The Moon covers about thirteen degrees a day, so it crosses into a new sign roughly every two and a half days — twelve or thirteen times in the four weeks below. These are the exact crossings, not the day they fall on.
Nearest, furthest, and eclipsed
The Moon’s orbit is not a circle. It runs between about 356,500 and 406,700 kilometres away, and the difference is visible: the same full moon is a seventh wider at perigee than at apogee. An eclipse needs the Moon to be not only full or new but close enough to the plane the Earth goes round the Sun in, which is why there is no eclipse every month.
How this one is built
Everything on this page is a computed position with a time attached. The phase comes from the elongation of the Moon from the Sun, the lit fraction from the actual geometry rather than from the cosine of that angle, and the four quarters are searched for rather than counted off an average month. A lunation is not 29.5 days: it runs between about 29.27 and 29.83, and the dates above are the ones this one actually has.
The disc is drawn lit on the right while the Moon is waxing, which is how it looks from the northern hemisphere. From the southern hemisphere it is the same moon the other way up. There is no orientation that is correct everywhere, so this page picks one and tells you which.
Void of course is the stretch at the end of a sign after the Moon has made its last exact aspect. What counts as an aspect is a real disagreement: this page uses the five Ptolemaic aspects to the six classical planets, which is the traditional definition. Counting the outer planets, or the minor aspects, makes the void shorter or does away with it almost entirely — which tells you how much of the idea is in the definition.
What you will not find here is a rule about what to do with any of it. A lunar calendar usually tells you when to cut your hair, sign a contract or start a diet. This one tells you where the Moon is. What that is worth on a given day is yours to decide, and nothing on this page is a prediction of anything that will happen.
Questions people ask
What is the Moon’s phase today?
The large disc at the top of this page is drawn for the minute you open it, with the name of the phase, how much of the face is lit and which day of the current lunation it is. Beside it are the Moon’s sign and degree, its age since the last new moon and its distance in kilometres. The row of small discs underneath covers the whole month: point at a day, or tap it, to see the phase on that day. It is all worked out on your device, in your own time zone.
What sign is the Moon in today?
The first line beside the disc gives the Moon’s sign and degree at the minute the page opens. The Moon goes round the zodiac in a little over twenty-seven days, so it moves into a new sign every two to three days, and the list headed Where the Moon goes next gives the exact time of each change for the coming four weeks. Astrology reads the Moon’s sign as colouring the mood of the day; this page gives the positions and leaves what to make of them to you.
What are perigee and apogee?
Perigee is the point in the Moon’s orbit nearest the Earth and apogee the point furthest away. The orbit is an ellipse, so the distance swings by around fifty thousand kilometres over each circuit of about twenty-seven and a half days. A full moon near perigee looks noticeably larger and brighter than one near apogee, which is what the popular word supermoon describes. This page lists the next perigee and apogee with the time of each and the distance in kilometres.
Why does the Moon look different in the southern hemisphere?
From the southern hemisphere you face north to see the Moon rather than south, so it appears the other way up: a waxing moon is lit on the left instead of the right, and the crescent seems to fill from the opposite side. The phase and the lit fraction are the same everywhere on Earth at the same moment. The discs on this page are drawn as the Moon looks from the northern hemisphere, lit on the right while waxing, so turn them round if you are south of the equator.