Analemma over the Callanish Stones
18.09.2022

If you went outside at the same time every day and took a picture that included the Sun, how would the Sun's position change? A more visual answer to that question is an analemma, a composite image taken from the same spot at the same time over the course of a year.

Discovery Spring
20.03.2001

Welcome to the equinox! Moving northward in Earth's sky, today the Sun crosses the celestial equator at 13:31 Universal Time bringing Spring to the north and Fall to the south. The change...

September s Aurora
23.09.2011

September's equinox arrives today at 0905 UT. As the Sun crosses the celestial equator heading south, spring begins in the southern hemisphere and autumn in the north. And though the seasonal connection is still puzzling, both spring and autumn bring an increase in geomagnetic storms.

Rings and Seasons of Saturn
19.09.2021

On Saturn, the rings tell you the season. On Earth, Wednesday marks an equinox, the time when the Earth's equator tilts directly toward the Sun. Since Saturn's grand rings orbit along...

APOD: 2025 October 9 Б The Jenga Moon
9.10.2025

That big, bright, beautiful Full Moon you watched rise on the night of October 6 was the Harvest Moon. Famed in festival, story, and song, Harvest Moon is just the traditional name of the full moon nearest the time of the northern hemisphere's autumnal equinox. According to lore the name is a fitting one.

September Sunrise Shadows
24.09.2022

The defining astronomical moment for this September's equinox was on Friday, September 23, 2022 at 01:03 UTC, when the Sun crossed the celestial equator moving south in its yearly journey through planet Earth's sky.

S is for Sun
21.03.2002

Taken yesterday from the SOHO spacecraft, this false-color image shows the active Sun near the March Equinox, the beginning of Fall in the south and Spring in the northern hemisphere. Recorded in a band...

Solar Eclipse Solargraph
22.09.2017

Today is the September equinox. Heading south, the Sun's path through the sky will cross the celestial equator at 20:02 UT. Of course the equinox date results in (mostly) equal night and day all over planet Earth.

Crescent Saturn
23.10.2007

Saturn never shows a crescent phase -- from Earth. But when viewed from beyond, the majestic giant planet can show an unfamiliar diminutive sliver. This image of crescent Saturn in natural color was taken by the robotic Cassini spacecraft in May.

Parthenon Moon
20.03.2011

Did you see the Full Moon last night? Near the horizon, the lunar orb may have seemed to loom large, swollen in appearance by the famous Moon illusion. But the Full Moon really...