Tag Archives: Great Red Spot

Incredible New Images Of Jupiter Reveal Details Behind Shrinking Great Red Spot

Jupiter: Are you ready for your close-up? A collection of images of the gargantuan planet, taken by Hubble, have been amalgamated into a planetary portrait, the first in a series of annual portraits of the gas giant members of the Solar System. Jupiter’s famous Great Red Spot, its dramatic cloud cover, and even a new elusive wave-like structure comprised of gas have been documented in incredible detail by NASA.

Collecting annual images of Jupiter, Saturn, Uranus and Neptune will help both current and future scientists observe how these enormous worlds change over time in fine detail, including any alterations to their weather patterns and atmospheric chemistry. Using Hubbles high-resolution Wide Field Camera 3, two global maps of Jupiter have been produced.

Video credit: NASA

Unfortunately, theres some bad news: The famousGreat Red Spot, that vast anti-cyclone with wind speeds of up to 644 kilometers per hour (400 miles per hour), is shrinking. This isnt breaking news for planetary scientists this storm, which can fit three entire planet Earths within its boundaries has been shrinking for perhaps the last four centuries. In the last 200 years, it has shrunk by over 50%. An unusual wispy structure has also been observed spanning almost the entire width of the Great Red Spot, rotating and distorting itself throughout the 10-hour-long image sequence span taken by Hubble.

Every time we look at Jupiter, we get tantalizing hints that something really exciting is going on, Amy Simon, a planetary scientist at NASAs Goddard Space Flight Center in Greenbelt, Maryland, said in a statement. This time is no exception.

This persistent hurricane which probably gets its orangey-red color from ammonium hydrosulfide chemically reacting with cosmic rays is still far older than any terrestrial superstorm, which normally last no longer than a week or so. Jupiters atmosphere is mostly comprised of hydrogen and helium, with a liquid ocean of hydrogen surrounding its relatively small rocky, icy core. As there is little solid ground to provide friction for the tumultuous atmosphere, storms and winds can continue unimpeded for centuries at the very least.

Simons research team think that the Great Red Spot is shrinking because smaller cyclones and anti-cyclones are feeding into the gigantic hurricane, distorting its vortex and causing a chaotic distribution of its internal energy. These parasitic storms could possibly one day sap enough momentum from the hurricane to cause its disintegration.

Up in Jupiters North Equatorial Belt, the existence of a second phenomenon, which was discovered only once decades earlier during the Voyager 2 mission, has been confirmed. This stealthy wave, found within the planets atmosphere at a latitude frequented by cyclones and anti-cyclones, appears similar in appearance to atmospheric waves on Earth. These terrestrial waves, so-called baroclinic waves,tend to appear when cyclones are beginning to form.

This elusive wave pattern on Jupiter has likely remained hidden for so long because it is often concealed beneath the clouds; when it emerges, wave crests are formed in the upper atmosphere, leaving a trace of its path.

A false-color image of the elusive wave pattern, with its wave crests indicated by the white arrows. Image credit: NASA

The long-term value of the Outer Planet Atmospheres Legacy program is really exciting, said co-author Michael H. Wong of the University of California, Berkeley, in the same statement. The collection of maps that we will build up over time will not only help scientists understand the atmospheres of our giant planets, but also the atmospheres of planets being discovered around other stars, and Earths atmosphere and oceans, too.

Think of the annual planetary portraits as the yearly school photograph for our very own Solar System. Just like a schoolchild being asked to sit still, Jupiter simply refuses.

Read more: http://www.iflscience.com/space/portrait-jupiter-reveals-detail-behind-shrinking-great-red-spot

Why Are Jupiter’s Storms Backwards?

Why do Jupiters storms rotate backwards compared to those on Earth? Scientists now think they have an answer and its all to do with gas flowing upwards from deep within the giant planet.

On Earth, the Coriolis effect causes our storms to rotate in the same direction as the rotation of the planet, but on Jupiter they rotate in the opposite direction. This new study, by scientists at the University of Alberta in Canada and the Max Planck Institute for Solar Research (MPS) in Germany, shows that an interaction between the layers of Jupiters atmosphere is the key to this phenomenon.The research is published in the journal Nature Geoscience.

Jupiter is made of mostly hydrogen and helium, and within 90 percent of the planets radius, the high pressure from the atmosphere above makes this mixture metallic and able to conduct electricity. Beyond this region, though, the gas is normalized in itsnon-metallic, gaseous state.

The interaction of rising gas and this outermost layer produces the weather patterns we can see. But on Earth the vortices of storms form at the bottom of these rising masses of air, whereas on Jupiter the vortices form at the top, in this upper layer of the atmosphere7,000 kilometers (4,350 miles) thick. According to the model, this accounts for the backwards movement of Jupiters storms relative to our planet.

The new model is pretty good, but it still can’t explain Jupiter’s fascinating Great Red Spot. Shown is a false color image of the storm from Voyager 1. NASA

“Our high-resolution computer simulation now shows that an interaction between the movements in the deep interior of the planet and an outer stable layer is crucial,” Johannes Wicht from the MPS said in a statement.

For the first time, the model was also able to successfully explain why Jupiters whirlwinds appear in wide bands north and south of the equator. It was within one of these bands that the mighty anticyclone known as the Great Red Spot, three times the size of Earth, has raged for more than 400 years.

However, as good as this new model is, it was unable to explain how anticyclones on Jupiter can last for many years, with storms in the simulation normally dissipating after just a few days. It suggests there is still much about Jupiter, particularly its Great Red Spot, that we still do not know.

“We are just beginning to understand Jupiters weather phenomena,”Wicht explained in the statement. “In addition to its size and durability, the Red Spot has other special features such as its characteristic color. Additional processes seem to be involved here that we dont yet comprehend.”

Read more: http://www.iflscience.com/space/mystery-jupiters-backwards-storms-solved-new-model