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Here's Looking At You: Spooky Shadow Play Gives Jupiter a Giant Eye


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The Hubble Space Telescope treats astronomers to gorgeous close-up views of the eerie outer planets. But it's a bit of a trick when it seems like the planet's looking back at you! In this view, the shadow of the Jovian moon Ganymede swept across the center of the Great Red Spot – a giant storm on the planet. This gave Jupiter the uncanny appearance of having a pupil in the center of a 10,000-mile-diameter "eye." Now if it blinks, we may really have to worry!

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      Media Contacts
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      NASA’s Goddard Space Flight Center, Greenbelt, Md.
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      Last Updated Mar 17, 2025 Editor Marty McCoy Contact Laura Betz laura.e.betz@nasa.gov Related Terms
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      This research was conducted as part of Webb’s General Observer Program 3548.
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      Downloads
      Right click any image to save it or open a larger version in a new tab/window via the browser’s popup menu.
      View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
      View/Download the research results from The Astrophysical Journal Letters.
      Media Contacts
      Laura Betz – laura.e.betz@nasa.gov
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Margaret W. Carruthers – mcarruthers@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
      Hannah Braun – hbraun@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
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      This animation begins with a view of the neighboring Andromeda galaxy. We zoom through a scattering of foreground stars and enter the inky blackness of intergalactic space. We cross 2.5 million light-years to reach the Andromeda system, consisting of 36 dwarf satellite galaxies orbiting the giant spindle-shaped Andromeda galaxy at image center. An ambitious survey by the Hubble Space Telescope was made to plot the galaxy locations in three-dimensional space. In this video we circle around a model of the Andromeda system based on real Hubble observational data. NASA, ESA, Christian Nieves (STScI), Alessandro Savino (UC Berkeley); Acknowledgment: Joseph DePasquale (STScI), Frank Summers (STScI), Robert Gendler The brightest companion galaxy to Andromeda is Messier 32 (M32). This is a compact ellipsoidal galaxy that might just be the remnant core of a larger galaxy that collided with Andromeda a few billion years ago. After being gravitationally stripped of gas and some stars, it continued along its orbit. Galaxy M32 contains older stars, but there is evidence it had a flurry of star formation a few billion years ago. In addition to M32, there seems to be a unique population of dwarf galaxies in Andromeda not seen in the Milky Way. They formed most of their stars very early on, but then they didn’t stop. They kept forming stars out of a reservoir of gas at a very low rate for a much longer time.
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      NASA’s Goddard Space Flight Center, Greenbelt, Maryland
      Ray Villard
      Space Telescope Science Institute, Baltimore, Maryland
      Science Contact:
      Alessandro Savino
      University of California, Berkeley, California
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      Details
      Last Updated Feb 27, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
      Hubble Space Telescope Andromeda Galaxy Astrophysics Astrophysics Division Galaxies Goddard Space Flight Center Spiral Galaxies Keep Exploring Discover More Topics From Hubble
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