September 4, 1997
In the time it took you to read this, the Earth moved another thousand miles through space. You are not standing still. You never have been.
Rivers in the Sun
Birthday · September 4, 1997
A little universe, just for you
Your date.
Ready to give.
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APOD published September 4, 1997. Full image credits are on the original APOD entry below. A publication-date match, not a photo taken on your date. Independent of NASA.
The surface of the Sun is shifting. By watching sunspots, it has long been known that our Sun rotates. It was also known that the center of the Sun rotates faster than the poles. Now, recent measurements by the Solar Oscillations Investigations group of the SOHO Observatory have found that the surface of the sun moves in other ways, too. Hot, electrically charged gas flows along and beneath the Sun's surface as depicted in the above computer generated diagram. The speed of these solar rivers is false-color coded with red hydrogen moving faster than blue. Over the course of a year plasma moves from the equator to the poles, while internal eddies circulate gas from deep inside the Sun. One surprise is the similarity to the motion of air in the Earth's atmosphere - indicating that scientists might learn more about Earth's global weather by studying the Sun.