What’s Up in the Sky in September?
It’s eclipse time! This month hosts 2025’s second eclipse season, where we’re treated to two eclipses: a total lunar eclipse and a partial solar eclipse.
Also, we’re coming up to the September equinox, meaning the days and nights are getting more equal—and it is aurora season.
| Date | Event* | What to See |
|---|---|---|
| Sep 7 | Full Moon | September’s Full Corn Moon is at its most illuminated at 18:08 UTC. |
| Sep 7–8 | Total lunar eclipse | See the Full Moon turn red in the longest totality since 2022. |
| Sep 16 | Moon-Jupiter conjunction | The Waning Crescent Moon meets up with Jupiter. |
| Sep 19 | Moon-Venus-Regulus alignment | An almost New Moon aligns with Venus and the star Regulus. |
| Sep 21/22 | Partial solar eclipse | The Moon’s shadow hits the bottom of our globe, giving us a partial solar eclipse. |
| Sep 22 | September equinox | The equinox at 18:19 UTC marks the start of fall or autumn in the Northern Hemisphere, and spring in the Southern Hemisphere. |
*Naked-eye events. Night Sky Map links are from New York City, USA.
Blood Moon on September 7–8
On September 7–8, Earth’s shadow will eclipse the Full Moon for the longest Blood Moon this year. Totality—where the Moon turns dark red—will last around 1 hour and 22 minutes. Anyone on the night side of Earth can see a lunar eclipse, and in this case, that is Australia, Asia, Africa, and Europe.
Eclipses are one of the highlights of our work at mungfali.galihkartiwa07.workers.dev. When things start to happen in the sky—exactly in line with calculations done many, many years before—it’s a slightly magical feeling.
Graham Jones, Live Eclipse Host
mungfali.galihkartiwa07.workers.devSolar Eclipse on September 21/22
On September 21/22, the Moon’s shadow hits the bottom of our globe, giving us a partial solar eclipse. New Zealand is in a prime position for this one, although the eclipse can be seen in various Pacific islands, parts of Antarctica, and a thin strip of Australia’s east coast. Although the eclipse date is September 21 in UTC time, New Zealanders will see it as the Sun rises the morning of Monday, September 22.
September Equinox: “Equal Night”
In the Northern Hemisphere, the September equinox is the autumnal or fall equinox, and is when night starts to become longer than day. But in the Southern Hemisphere, it’s the spring equinox, and the day starts to become longer than night.
However, even though on the day of the equinox the amount of day and night is almost equal in both hemispheres, it is not how an equinox is defined in astronomy.
For astronomers, the equinox is the moment the Sun crosses the celestial equator. This is another way of saying that the Sun lies directly above a point on Earth’s equator. Using this definition, the September equinox is on September 22 at 18:19 UTC.
What are equinoxes and solstices?The Mayan Sun Snake
Around the time of both fall and spring equinox, when the Sun shines directly on the equator, a 36-meter (120-foot) serpent of sunlight slithers down the stairs of the Mayan El Castillo pyramid (Temple of Kukulcán) at Chichén Itzá, Mexico .
The limestone pyramid was built as a temple to the feathered serpent deity Kukulcán, and demonstrates the Mayan knowledge of architecture, geometry, and astronomy. Thousands visit the temple each equinox to see the serpent of light.
Equinox Means Aurora Season
The equinox not only marks the shifting balance between night and day, it is also linked to the aurora—curtains of light that dance across the night sky in the polar regions. Aurora activity increases around both the September and March equinoxes.
Scientists think this is because of two things that happen during this time of year. Firstly, the Sun and Earth’s magnetic fields line up in just the right way. Secondly, the Earth’s magnetic poles are at a right angle to the flow of the solar wind. The first is known as the Russell-McPherron effect, and the second as the equinotical effect. Together, they open the door wider for charged particles from the Sun to stream into our upper atmosphere, creating northern and southern lights.
Why 2025 is a good year for aurorasSeptember Stargazing
Around September 8, the Moon meets up with Saturn. It will be possible to see the close approach between an almost Full Moon and the Ringed Planet all night, so look up and enjoy.
Just over a week later, around September 16, the Waning Crescent Moon can be seen next to Jupiter. Look up just before sunrise to find the pair in the night sky.
Around September 19, an almost New Moon aligns with Venus and the star Regulus. The trio will rise around sunrise, getting lost in the glare of the Sun in the early morning.
Remember: Do not try to observe objects close to the Sun while any part of the Sun is above the horizon. Never point binoculars or a telescope in the direction of the Sun—it can cause permanent eye damage.