Most recent images from Hubble space telescope show giant red spot on planet’s atmosphere has continued to shrink and has become more circular.
Two images of Jupiter by the Hubble Space Telescope taken at different times on 19 January 2015 reveal cloud movement and confirm the red spot to have turned orange.
The raging storm that creates Jupiter’s great red spot has waned and turned the planet’s famous blemish to orange, according to the most recent images from the Hubble space telescope.
Scientists trained the veteran observatory on Jupiter to capture the first of a series of annual portraits of the solar system’s outer planets.
The images reveal that the giant red spot in Jupiter’s atmosphere continued to shrink and become more circular this year, narrowing by about 150 miles (240km) since 2014. One hundred years ago, the spot was around 25,000 miles (40,000km) wide, it is now less than half that width.
At the heart of the storm is an unusual wispy filament that spans almost the full width of the spot and is blown around by Jovian winds that top 335 miles per hour (540kph).
Another curious feature is a wave similar to baroclinic waves that form in Earth’s atmosphere where cyclones are forming, and is passing through a region populated with cyclones and anti-cyclones. This wave has been spotted only once before when the Voyager 2 spacecraft captured faint images decades ago.
“Until now, we thought the wave seen by Voyager 2 might have been a fluke,” said Glenn Orton at Nasa’s Jet Propulsion Laboratory in Pasadena, California. The wave is thought to form beneath Jupiter’s clouds and then rise up through the cloud deck.
Hubble’s annual portraits, taken with the Wide Field Camera 3, give researchers the material they need to observe changes in the appearance of planets year after year.
The latest images, taken over a 10-hour period, allowed scientists to create two new maps of Jupiter. From these, they can calculate the speeds of the winds that tear through Jupiter’s atmosphere, and to track some of its most distinguishing features.
The space telescope has taken further images of other planets in the outer solar system, namely Neptune and Uranus, with Saturn due to be added later. All of the maps created from the images will be placed in Nasa’s public archive as part of the Outer Planet Atmospheres Legacy programme.
“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,” said Michael Wong at the University of California in Berkeley.