Hubble portrait of Jupiter captures new changes in Great Red Spot
Scientists using NASA’s Hubble Space Telescope have produced new maps of Jupiter as part of series of annual portraits of the Solar System’s outer planets. Collecting these images yearly will help researchers to learn about how these giant planets change over time. The images of Jupiter have already revealed a previously unseen filament in the core of the Great Red Spot and a rare wave just north of the planet’s equator.
“Every time we look at Jupiter, we get tantalizing hints that something really exciting is going on,” said Amy Simon, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This time is no exception.”
Simon and her fellow researchers produced two global maps of Jupiter using images captured by Hubble’s Wide-Field Camera 3. The two maps are from nearly back-to-back rotations of Jupiter, making it possible to estimate the speed of Jupiter’s winds. A paper describing the team’s findings was published in Astrophysical Journal.
The new data confirms that Jupiter’s Great Red Spot is continuing to shrink and become more circular, as it had been doing for years. The long axis of the gigantic storm is about 150 miles (240 kilometers) shorter than it was in 2014. While the storm had been recently shrinking at a faster-than-normal rate, the most recent changes are consistent with the long-term trend.
The Great Red Spot is actually more orange than red and its core, which usually is more intense in color, is less distinct than it used to be. Hubble detected an unusual wispy filament that spans nearly the entire width of the vortex. This streamer rotates and twists through the 10-hour span of the Great Spot image sequence, being distorted by winds blowing at 330 miles per hour (150 meters per second) or more.
The researchers also found an elusive wave in Jupiter’s North equatorial belt that had only been once before, by Voyager 2. The current wave was found traveling at about 16 degrees north latitude in a region dotted with cyclones and anticyclones. Similar waves, called baroclinic waves, occasionally appear in Earth’s atmosphere where cyclones are forming.
“Until now, we thought the wave seen by Voyager 2 might have been a fluke,” said co-author Glenn Orton of NASA’s Jet Propulsion Laboratory in Pasadena, California. “As it turns out, it’s just rare!”
The wave may originate in a clear layer beneath the clouds and only become visible when it propagates into the cloud deck. This idea is supported by the distance between the wave crests.
The scientists have also observed Neptune and Uranus and maps of those planets will be added to the public archive. Saturn will also be added to the series. The Hubble telescope will make observations each year for this special set of planetary portraits known as the Outer Planet Legacy program (OPAL).
“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. “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.”
Video courtesy of NASA
Jim Sharkey is a lab assistant, writer and general science enthusiast who grew up in Enid, Oklahoma, the hometown of Skylab and Shuttle astronaut Owen K. Garriott. As a young Star Trek fan he participated in the letter-writing campaign which resulted in the space shuttle prototype being named Enterprise. While his academic studies have ranged from psychology and archaeology to biology, he has never lost his passion for space exploration. Jim began blogging about science, science fiction and futurism in 2004. Jim resides in the San Francisco Bay area and has attended NASA Socials for the Mars Science Laboratory Curiosity rover landing and the NASA LADEE lunar orbiter launch.