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Birthday · August 21, 2026

August 21, 2026

Here’s to you, and all the wonder still ahead.

Time-Lapse of the Star S301 Orbiting the Black Hole in the Center of the Galaxy

APOD published August 21, 2026

Full image credits: original APOD

apod.nasa.gov/apod/ap260821.html

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Selected image source ↗ APOD published August 21, 2026. Full image credits are on the original APOD entry below. A publication-date match, not a photo taken on your date. Independent of NASA.

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Time-Lapse of the Star S301 Orbiting the Black Hole in the Center of the Galaxy

Original APOD · August 21, 2026 ↗

Read the original APOD for the astronomer’s explanation and full image credits. Its text is preserved in the archive as published.

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What does it feel like to zoom around a spinning supermassive black hole? The featured video is an animation showing a time-lapse of 4 years of observations of the star S301 orbiting Sagittarius A*, the 4-million-solar-mass black hole in the center of our Galaxy. S301 was discovered in 2023 with the Very Large Telescope Interferometer of the European Southern Observatory, located in the Atacama Desert in Chile. Astronomers recently found that S301 takes approximately 8.7 years to go around the black hole and reaches speeds of 25,000 km/s. It comes closer to the black hole than any other stars detected before, at a distance similar to that from Saturn to the Sun. Because it comes so close to Sagittarius A*, S301 could be used to directly measure how fast the black hole spins and test Einstein's theory of general relativity. According to the theory, a spinning black hole drags the fabric of spacetime around itself, affecting the orbits of close-by objects.

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