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 September 23
A picture shows a starfield with three prominent objects.
A blue spiral galaxy is on the lower left and another blue spiral
is just left of center. Toward the upper right is a light-colored
comet with a tail fading toward in the image bottom.
Please see the explanation for more detailed information.

Comet Tsuchinshan-ATLAS Approaches
Image Credit & Copyright: Brian Valente & Greg Stein

Explanation: What will happen as this already bright comet approaches? Optimistic predictions have Comet C/2023 A3 (Tsuchinshan–ATLAS) briefly becoming easily visible to the unaided eye -- although the future brightness of comets are notoriously hard to predict, and this comet may even break up in warming sunlight. What is certain is that the comet is now unexpectedly bright and is on track to pass its closest to the Sun (0.39 AU) later this week and closest to the Earth (0.47 AU) early next month. The featured image was taken in late May as Comet Tsuchinshan–ATLAS, discovered only last year, passed nearly in front of two distant galaxies. The comet can now be found with binoculars in the early morning sky rising just before the Sun, while over the next few weeks it will brighten as it moves to the early evening sky.

Your Sky Surprise: What picture did APOD feature on your birthday? (post 1995)
Tomorrow's picture: dusty baboon


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