Hubble Space Telescope Captures Changes In Jupiter’s Atmosphere As Storm Abates And Great Red Spot Shrinks, Turns Orange

Thanks to a new series of photographs taken by the Hubble Space Telescope over a 10-hour period, scientists have discovered that Jupiter’s famous Great Red Spot is shrinking, and that the giant storm is now more orange than red.

The images — the first in a series of annual photographs that will be taken by the Space Telescope to track changes in the planets of the outer solar system — reveal that Jupiter’s Great Red Spot has continued to shrink, and become more circular this year. The Hubble Space Telescope’s pictures show that the spot has shrunk roughly 150 miles since the last time it was photographed, in 2014. A hundred years ago, Jupiter’s Great Red Spot was around 25,000 miles wide. Now, however, it is less than half that width.

The change in color of the spot, as revealed by the Hubble Space Telescope images, is due to the fact that the storm raging within it for at least the last 300 years has begun to wane, reports the Guardian. Directly in the center of the spot is what scientists are calling “an unusual wispy filament” that spans almost the entire width of the storm. This unusual filament is blown around the vortex by Jovian winds of up to 335 miles per hour.

The 10-hour photo shoot captured by Hubble also shows another interesting feature in the planet’s atmosphere: a rare wave structure just north of Jupiter’s equator, that mimics baroclinic waves sometimes seen in Earth’s atmosphere when cyclones are forming. This wave structure was originally seen nearly four decades ago, in 1977, by Voyager 2, but due to the fact that it was barely visible in the original photographs, scientists had begun to think it was a fluke, says Glenn Orton at Nasa’s Jet Propulsion Laboratory in Pasadena, California.

“Until now, we thought the wave seen by Voyager 2 might have been a fluke.”

The new images taken by the Hubble Space Telescope, however, reveal that the wave structure is actually very real, and is in a region of the planet’s atmosphere that is densely populated with cyclones and anticyclones. According to the report on the Hubble Space Telescope’s website, it is believed that the wave may originate beneath the clouds, and is therefore only visible when it breaches the cloud deck, which would account for it having only been seen once before, by Voyager 2.

The stunning images of Jupiter were taken by the Hubble Space Telescope’s Wide Field Camera 3, and have allowed researchers to create two maps of the entire planet that make it possible for scientists to determine the speeds of Jupiter’s winds, track potential changes in the planet’s features, and identify any number of phenomena in Jupiter’s atmosphere.

The Hubble Space Telescope’s images of Jupiter are the first in a series of yearly photographs that will be taken of the planets in the outer solar system, as part of the Outer Planet Atmospheres Legacy (OPAL) program. This program will allow Hubble to dedicate some time, each year, to observing and photographing the outer planets, in the hopes of further understanding the atmospheres of the giant planets in our solar system, says Michael Wong at the University of California in Berkeley.

“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 Earth’s atmosphere and oceans, too.”

In addition to Jupiter, the Hubble Space Telescope has also observed and photographed Neptune and Uranus, with Saturn scheduled to be added at a later date. The maps of these distant planets created from Hubble’s photographs will be placed in NASA’s public archive as part of the OPAL program.

[Image Credit: NASA / Newsmakers / Getty Images]