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Milky Way

The galaxy that contains our Solar System, characterized by its barred spiral structure with multiple spiral arms extending from a central bar.

Source: esa.int

APODs including "Milky Way"

Equinox at the Pyramid of the Feathered Serpent

15/03/2026

Equinox at the Pyramid of the Feathered Serpent
Image Credit: Robert Fedez / NASA APOD

To see the feathered serpent descend the Mayan pyramid requires exquisite timing. You must visit El Castillo -- in Mexico's Yucatán Peninsula -- near an equinox. Then, during the late afternoon if the sky is clear, the pyramid's own shadows create triangles that merge into the famous illusion of a slithering viper. Also known as the Temple of Kukulkan, the impressive step-pyramid stands 30 meters tall and 55 meters wide at the base. Built up as a series of square terraces by the pre-Columbian civilization between the 9th and 12th century, the structure can be used as a calendar and is noted for astronomical alignments. The featured composite image was captured in 2019 with Jupiter and Saturn straddling the diagonal central band of our Milky Way galaxy. In a few days another equinox will occur -- not only at Temple of Kukulcán, but all over planet Earth.