Rough Notes:

Poseidon Aegaeus

Neptune's clouds in false color

Neptune's clouds in false color. Credit: NASA/Hubble Heritage Team.

Nov 14, 2011

Neptune is the Solar System’s most remote planet. What drives its extraordinary winds?

The winds on Jupiter average about 400 kilometers per hour, with the fastest streaming around the Great Red Spot at 635 kilometers per hour. On Saturn, wind speeds up to 1800 kilometers per hour have been clocked by the orbiting Cassini spacecraft, while Hubble Space Telescope observations of Uranus show the cloud bands blowing at 900 kilometers per hour. On Neptune, a place so cold that nitrogen, oxygen, and argon could freeze into solids, winds around the Great Dark Spot are moving at almost 2000 kilometers per hour.

According to conventional theories, planetary winds are caused by convention: cold air flowing into regions of warm air. That convection is thought to be from solar energy selectively heating different atmospheric regions, causing gases to rise and fall. Why is it that the planets receiving the least solar energy experience the greatest convection? On Neptune, for instance, the Sun is 900 times dimmer than seen on Earth, yet the average winds on our planet are a mere 56 kilometers per hour. The fastest wind was recorded on December 17, 1997: 378 kilometers per hour on the island of Guam.

It seems illogical that the initiator of Neptune’s wind speed is presumed to be the Sun heating a gas giant planet 49,500 kilometers in diameter from 4.486 X 10^6 kilometers away. Presumption would seem to require something more like amazement that such a tiny pinpoint of light in space—little more than a bright star from Neptune’s perspective—could stimulate this large effect.

Consensus astronomers and Electric Universe advocates are both at a disadvantage when it comes to Neptune. Only the Voyager 2 spacecraft has visited the frozen giant, flying by on its rendezvous with deep space at almost 62,000 kilometers per hour, 4900 kilometers above Neptune’s north pole. The recently upgraded Hubble Space Telescope has been observing Neptune for only a few years. Since seasons on Neptune average around 40 years (based on its 165 year orbit and 29 degree inclination), astronomers have had little time to gather data about changes in its atmosphere.

Comments from Lawrence A. Sromovsky, a senior scientist at University of Wisconsin, Madison’s Space Science and Engineering Center and a leading authority on Neptune’s atmosphere, provide an insight into the conventional view. Neptune possesses a “…trivial amount of energy available to run the machine that is Neptune’s atmosphere. It must be a well-lubricated machine that can create a lot of weather with very little friction.”

Looking at Neptune using a strictly fluid dynamic model derived from atmospheric convection ignores the electrical environment in which all members of the Solar System are immersed.

Conventional theory defines wind as the movement of air molecules. The Electric Universe theory agrees with that idea, but there is more to the explanation. Electrostatic discharges in planetary atmospheres are common throughout the Solar System, possibly on Neptune as well. Since lightning requires the separation of electric charge, it requires cloud layers of varying density and composition. Neptune exhibits high-altitude methane clouds, a hydrogen sulfide-methane layer, and layers of water and ammonium hydrosulfide deeper down. So-called “whistlers” have been detected in Neptune’s magnetosphere, but no direct observation of lightning.

If wind is supposed to be nothing more than convection and gas kinetics, Electric Universe proponents would insist that electric discharges also generate wind. Electromagnetic forces move and accelerate charged particles in plasma, so the neutral air molecules get dragged along with them. Laboratory arc discharges reveal that an electric “wind” surrounds and often precedes an electric arc.

Plasma discharges in Neptune’s atmosphere are probably sweeping up the surrounding air along with the charge carriers, or ions. No doubt the same phenomenon on a greater or lesser scale is happening in the atmosphere of every planet. By analogy, the accepted explanation of thunderstorms on Earth being caused by the convection of hot air generated by the Sun’s heat alone is open to question.

Stephen Smith