Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2024 March 19
The sun sets in the distance at the horizon end of
a long road over open country. The sunset is very orange,
as is the surrounding sky. Telephone poles line the right
side of the road.
Please see the explanation for more detailed information.

A Picturesque Equinox Sunset
Image Credit & Copyright: Alan Dyer,, TWAN

Explanation: What's that at the end of the road? The Sun. Many towns have roads that run east - west, and on two days each year, the Sun rises and sets right down the middle. Today, in some parts of the world (tomorrow in others), is one of those days: an equinox. Not only is this a day of equal night ("aequus"-"nox") and day time, but also a day when the sun rises precisely to the east and sets due west. Displayed here is a picturesque rural road in Alberta, Canada that runs approximately east -west. The featured image was taken during the September Equinox of 2021, but the geometry remains the same every year. In many cultures, this March equinox is taken to be the first day of a season, typically spring in Earth's northern hemisphere, and autumn in the south. Does your favorite street run east - west? Tonight, at sunset, you can find out with a quick glance.

Tomorrow's picture: open space

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