Great Red Spot makes Jupiter hot, study suggests - Action News
Home WebMail Thursday, November 14, 2024, 04:37 PM | Calgary | 6.6°C | Regions Advertise Login | Our platform is in maintenance mode. Some URLs may not be available. |
Science

Great Red Spot makes Jupiter hot, study suggests

Why is distant Jupiter as warm as Earth? The answer may be The Great Red Spot, an enormous storm big enough to swallow three Earths that has been raging on Jupiter for at least three centuries, a study showed on Wednesday.

Upper atmosphere above massive storm is hundreds of degrees hotter than anywhere else on planet

Jupiter's massive storm

8 years ago
Duration 0:40
Does the Great Red Spot heat the entire planet?

Scientists havelong wondered why Jupiter's upper atmosphere has temperaturessimilar to those of Earth, even though the biggest planet in thesolar system is five times farther away from the sun.

The answer may be The Great Red Spot, an enormous storm bigenough to swallow three Earths that has been raging on Jupiterfor at least three centuries, a study showed on Wednesday.

Turbulent atmospheric flows above the Great Red Spot produce both gravity waves and acoustic waves. Gravity waves are much like how a guitar string moves when plucked, while acoustic waves are compressions of the air (sound waves!). Heating in the upper atmosphere 500 miles above the storm is thought to be caused by a combination of these two wave types crashing like ocean waves on a beach. (Art by Dillon Yothers with Luke Moore)

Using an infrared telescope at Hawaii's Mauna KeaObservatory, scientists discovered that the upper atmosphere
above the Great Red Spot the largest storm in the solar systemis hundreds of degrees hotter than anywhere else on theplanet.

It could be a coincidence or a major clue, said BostonUniversity physicist James O'Donoghue, lead scientist of the
study published in the journal Nature.

The Great Red Spot is an enormous storm big enough to swallow three Earths that has been raging on Jupiter for at least three centuries. (NASA/JPL/Space Science Institute)

The storm spans 22,000 kilometresby12,000 kilometres(13,670 miles by 7,456 miles) and is located in Jupiter's lower atmosphere. The topof its clouds reach altitudes of about 50 kilometres(31 miles).

By a process of elimination, the newly found hot spot mustbe heated from below, the study concluded.

Heat transfer method unknown

The finding provides a strong link between Jupiter's upperand lower atmosphere, though the exact process by which heat istransferred remains unknown. The most-likely energy source isacoustic waves that provide heat from below, the study said.

Bright regions at the poles result from auroral emissions; the contrast at low- and midlatitudes has been enhanced for visibility. Great Red Spot (GRS) emissions at midlatitudes are indicated by the red arrow, showing that it is hundreds of degrees hotter than anywhere else on the planet. (J. ODonoghue, NASA Infrared Telescope Facility (IRTF))

Scientists also are unsure why the storm is brick red, norwhy it has changed color over time. In a 1900 report in the
Seattle Post-Intelligencer, scientists described the oval stormas salmon pink. Recent images from the Hubble Space Telescopeshow it has become orange tinged and more circular.

Like a hurricane on Earth, the Spot's center is relativelycalm, but farther out winds reach 430 kilometres per hourto680 kilometres per hour (270 mph to 425 mph). Because there is no land on Jupiter, which is madealmost entirely of hydrogen and helium, the storm can never makelandfall and dissipate.

"The Great Red Spot is like a wheel that's wedged betweentwo conveyor belts running in opposite directions," said
planetary scientist Glenn Orton, with NASA's Jet PropulsionLaboratory in Pasadena, Calif.

"One is adding momentum to it at the top, and another isadding momentum at the bottom. Together, they feed the vortexand essentially keep it alive."

The exact process by which heat is transferred from the Great Red Spot to the upper atmosphere remains unknown. The most-likely energy source is acoustic waves that provide heat from below, the study said. (Art by Karen Teramura, UH IfA, James ODonoghue)

But the storm may not be alive much longer. It has beenshrinking for the last 100 years, Orton said.

More information is expected from NASA's Juno spacecraft,which arrived at Jupiter on July 4.