What Causes Jupiter’s Red Storm?

At one time, the storm was at least 20,000 miles (32,000 km) in diameter and big enough to envelop three Earths. It is similar to a hurricane on Earth, rotating counterclockwise with a maximum windspeed of 268 miles per hour (430 km/h), almost twice as fast as the worst hurricanes on Earth. Historic observations date as far back as the 1600s. Since then, the spot has changed, fluctuating between a deep red and a pale salmon color. Laboratory experiments suggest that complex organic molecules, red phosphorus, and other sulfur compounds cause the vibrant color.

But since the 1930s, the storm has shrunk to half its largest diameter. Even though it may be dwindling in size, the longevity and enormity of our solar system’s biggest storm is full of mystery. The reason for the persistence of the Great Red Spot is unknown, but presumably comes from the fact that it never moves over land, unlike hurricanes on Earth. Jupiter is composed of hydrogen and a small amount of helium and has no “land” in its form. Jupiter’s internal heat source is a driving force, and the spot tends to absorb nearby weaker storms. However, based on computer models, the spot should have disappeared after several decades. Waves and turbulence in and around the storm sap it of energy. The powerful jet streams that surround the spot should slow its spinning. And even though the storm absorbs smaller ones, researchers say that doesn’t happen enough to explain the storm’s longevity. Some scientists think vertical flows in the storm are just as important as the more-studied horizontal flows. When the storm loses energy, vertical flows move hot and cold gases in and out of the storm, restoring energy. Understanding Jupiter’s red storm could reveal more clues about the vortices in Earth’s oceans and also the nurseries of stars and planets. Philip Marcus, a fluid dynamicist and planetary scientist at the University of California at Berkeley, explains the importance of understanding the Great Red Spot: “Vortices with physics very similar to the GRS are believed to contribute to star and planet formation processes, which would require them to last for several million years”—even as the Great Red Spot shrinks, it retains enormous significance for Earth and the very beginnings of the solar system.

Comments

How Will the Universe End?

In 1929, Edwin Hubble discovered that the universe is not in fact static, but expanding. In the years following his discovery, cosmologists took up the implications of the discovery, asking how long the universe had been expanding, what forces caused the expansion, and whether it will ever cease. Cosmologists are pretty confident about the first question: just shy of 14 billion years. A great deal of evidence supports the predominant answer to the second question: The universe rapidly emerged from a singularity in an event that cosmologists call the Big Bang. The third question is a bit more mysterious, and the answer relies on an obscure, confounding phenomenon known as dark energy. The density of dark energy in the universe determines its ultimate fate. In one scenario, the universe does not possess enough dark energy to forever counteract its own gravity and thus ends in a “Big Crunch.” Under this scenario, the universe’s gravity will overcome its expansio...

What Causes Volcanic Lightning?

On March 10, 2010, Eyjafjallajökull volcano, a caldera in Iceland covered by an ice cap, erupted. It sent plumes of clouds across most of Europe and the Atlantic Ocean. Photos of the eruption show lightning originating and ending in the cloud of ash that hovered over the volcanic opening. The largest volcanic storms are similar to supercell thunderstorms that spread across the American Midwest. But while those thunderstorms are fairly well understood, volcanic lightning still remains mysterious. The remote location of volcanoes and infrequent eruptions make volcanic lightning difficult to study. In general, lightning occurs through the separation of positively and negatively charged particles. Differences in the aerodynamics of the particles separate the positive and negative. When the difference in charge is great, electrons flow between the positive and negative regions. A lightning bolt is a natural way of correcting the charge distributi...

Is the Mpemba Effect Real?

For more than 2,000 years, scientists have observed the unique phenomenon that, in some conditions, hot water freezes faster than cold water. In the fourth century B.C.E., Greek scientist Aristotle noted, “The fact that the water has previously been warmed contributes to its freezing quickly: for so it cools Sooner. Seventeenth-century English scientist Francis Bacon noted, "slightly tepid water freezes more easily than that which is utterly cold.” Several years later, French mathematician René Descartes echoed his predecessors' observations, writing, "One can see by experience that water that has been kept on a fire for a long time freezes faster than other." Given the centuries old knowledge that hot water does indeed freeze faster than cold in certain circumstances, it should have come as no surprise when Tanzanian schoolboy Erasto Mpemba claimed in his science class in 1963 that ice cream would freeze faster if it w...

knowledge

Search This Blog