Saturn's Rotational Period Difficult To Determine

After recently measuring radio signals from Saturn, scientists discovered that at 10 hours, 45 minutes, 45 seconds (plus or minus 36 seconds), the Saturnian day now appears to be 6 minutes longer than than the Voyager 1 and 2 readings showed. Scientists believe this may may due to a change in the rotational speed of Saturn's magnetic field and not an actual slowdown of the planet's physical rotation. This discovery may indicate that the magnetic field rotation in gas giants like Saturn behaves more like in our own sun, having a rotational period that varies with latitude. Measuring emitted radio signals from "gas giants" has been the most accurate method for determining the rotational periods of these planets, since any surface features are obscured by thick, swirling atmospheres.

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