FYFD

Tag: anticyclone

  • The Great Red Spot’s Cycle

    The Great Red Spot’s Cycle

    First spotted by humanity in 1664, Jupiter‘s Great Red Spot is a seemingly endless storm. Strictly speaking, there is debate as to whether observations prior to 1831 were of the same storm, but there’s no denying that the storm has raged unabated since regular observations began in the first half of the nineteenth century. Despite its longevity, the Great Red Spot is not unchanging. Overall, its major axis is shrinking, making the storm more circular over time. The storm also has a 90-day cycle in which its size, shape, and brightness vary, as seen below. Researchers note that the changes are relatively subtle — at least to the eye — but now that they’ve been identified, it may be possible to use amateur astronomers’ data to track these variations more closely. (Image credits: GRS – K. Gill/NASA, snapshots – A. Simon et al.; research credit: A. Simon et al.; via Gizmodo)

    Over a 90 day cycle, Jupiter's Great Red Spot oscillates in size, shape, and other characteristics.
    Over a 90 day cycle, Jupiter’s Great Red Spot oscillates in size, shape, and other characteristics.
  • Jupiter On Display

    Jupiter On Display

    The rich detail of Jupiter’s atmosphere is on full display in this enhanced-color image from the Juno spacecraft. (Full resolution version here – trust me, you want to click that link.) To the north, on the left side of the image, Jupiter’s Great Red Spot swirls. To the center and right, the cloud bands of Jupiter’s southern region are coming into view. The color enhancements really highlight eddies on the edge of these bands. These are examples of Kelvin-Helmholtz instabilities caused by shear between cloud bands moving at different speeds. Within the bands, smaller vortices spin. Some of these are anti-cyclones, high-pressure storm systems found all over the planet. Jupiter’s atmosphere still holds many mysteries for scientists, but I love how every gorgeous image Juno sends back shows fluid physics written larger than life across our solar system’s biggest planet. (Image credit: NASA/JPL-Caltech/SwRI/MSSS/G. Eichstädt /S. Doran; via Gizmodo)

  • Featured Video Play Icon

    Perijove

    The Juno spacecraft continues to send back incredible photos of Jupiter’s atmosphere. This video animates images from the sixth close pass of Jupiter to give you a sense of what Juno sees as it swoops by our system’s largest planet. The trajectory passes from the north pole to the south, showing Jupiter’s whitish zones, dark belts, and massive storms. Up close Jupiter looks like an Impressionist painting, all vortices and shear instabilities. The large white spots you see are enormous counterclockwise rotating vortices known as anticyclones – many of them larger than our entire planet. (Video credit: NASA / SwRI / MSSS / G. Eichstädt / S. Doran)