- 3 Aug, 14:25 Vilnius time: last quarter.
- 10 Aug, 05:27 Vilnius time: new moon.
- 17 Aug, 08:00 Vilnius time: first quarter.
- 25 Aug, 12:06 Vilnius time: full moon, traditionally the Sturgeon Moon.
- During August 1991 the Moon passes through all eight phases. One full cycle takes about 29.5 days.
- The next full moon after this month is on 24 September 1991 (September 1991).
Moon phase times, August 1991
The four principal phases are moments, not whole days. Times are given in UTC and in Europe/Vilnius time.
| Date | Phase | Europe/Vilnius | UTC |
|---|---|---|---|
| Sat 3 Aug | Last quarter | 14:25 | 11:25 |
| Sat 10 Aug | New moon | 05:27 | 02:27 |
| Sat 17 Aug | First quarter | 08:00 | 05:00 |
| Sun 25 Aug | Full moon · Sturgeon Moon | 12:06 | 09:06 |
The sky: August 1991
Planets and sky events this month, as seen in London. The Moon's phases are in the calendar above.
Planets visible (mid-month)
Events
| Thu 8 Aug | Mercury and Venus together | 2.1° apart, but not in a dark sky. |
| Sun 11 Aug | The Moon near Mercury | About 0.6° apart, but Mercury is not visible that night. |
| Sun 11 Aug | The Moon near Venus | About 2.8° apart, but Venus is not visible that night. |
| Mon 12 Aug | The Moon near Mars | About 5.3° apart, but Mars is not visible that night. |
| Mon 12 Aug | Perseids meteor shower peak | Up to 100 meteors an hour in a perfect sky. The Moon is 13% lit and will not interfere. |
| Thu 22 Aug | The Moon near Saturn | About 1.7° apart. Look for Saturn next to the Moon. |
How to read the moon calendar
Each day shows its date, the share of the Moon’s disc that is lit at noon, and the Moon’s shape that day. When a full moon, new moon or quarter falls on a day, it is named at the bottom of the cell.
Illumination is the part of the disc lit by the Sun. It grows from new moon to full moon (waxing) and shrinks from full moon to new moon (waning). Each day opens its own page with every signal for that date.
Full moon dates 1991
| Date | Time (UTC) | Traditional name | |
|---|---|---|---|
| Wed 30 Jan | 06:09 | Wolf Moon | passed |
| Thu 28 Feb | 18:24 | Snow Moon | passed |
| Sat 30 Mar | 07:17 | Worm Moon | passed |
| Sun 28 Apr | 20:58 | Pink Moon | passed |
| Tue 28 May | 11:36 | Flower Moon | passed |
| Thu 27 Jun | 02:58 | Strawberry Moon | passed |
| Fri 26 Jul | 18:24 | Buck Moon | passed |
| Sun 25 Aug | 09:06 | Sturgeon Moon | passed |
| Tue 24 Sep | 22:39 | Harvest Moon | passed |
| Wed 23 Oct | 11:07 | Hunter’s Moon | passed |
| Fri 22 Nov | 22:56 | Beaver Moon | passed |
| Sat 21 Dec | 10:22 | Cold Moon | passed |
New moon dates 1991
| Date | Time (UTC) | |
|---|---|---|
| Wed 16 Jan | 23:49 | passed |
| Thu 14 Feb | 17:31 | passed |
| Sat 16 Mar | 08:10 | passed |
| Sun 14 Apr | 19:37 | passed |
| Tue 14 May | 04:35 | passed |
| Wed 12 Jun | 12:05 | passed |
| Thu 11 Jul | 19:05 | passed |
| Sat 10 Aug | 02:27 | passed |
| Sun 8 Sep | 11:00 | passed |
| Mon 7 Oct | 21:38 | passed |
| Wed 6 Nov | 11:10 | passed |
| Fri 6 Dec | 03:56 | passed |
The eight moon phases explained
Four principal phases are exact instants; the four in between are the days that connect them.
Solar and lunar eclipses in 1991
No eclipse data for 1991.
The waning moon is traditionally a time for finishing
Questions people ask
When is the full moon in August 1991?
The full moon is on 25 August 1991. Its traditional name is the Sturgeon Moon. The exact time is in the table on this page.
When is the new moon in August 1991?
The new moon is on 10 August 1991. The Moon can’t be seen that night: it sits between Earth and the Sun with its lit side turned away.
What do the percentages mean?
They show how much of the Moon’s disc is lit at noon. 0% is new moon, 100% is full moon and 50% is a quarter.
Why does another calendar give a different date?
A phase is a moment. When it falls near midnight, the date can differ by one day between time zones. This calendar uses Europe/Vilnius time for the days.
How often is there a full moon?
About every 29.5 days. Some months have two; the second is called a Blue Moon.
- Jean Meeus, Astronomical Algorithms, 2nd ed., Willmann-Bell, 1998, chapters 48 and 49.
- NASA Eclipse Web Site (eclipse dates and visibility).
Numbers update through the day from public sources. The text for each day is written from that day’s data and checked by the editor. Every past day keeps its own page in the archive.