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Io, Prometheus Plume
Credit: Galileo Project, JPL, NASA
Two sulfurous eruptions are visible on Jupiter's volcanic moon Io.
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Io Volcano Plume
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
This still from five-frame photo sequence by NASA's New Horizons mission captures the giant plume from the Tvashtar volcano on Jupiter's moon Io. Only the upper part of the plume is visible from this vantage point. The plume's source is 130 km (80 miles) below the edge of Io's disk, on the far side of the moon. The New Horizons spacecraft captured this view during a flyby on March 1, 2007, while en route to Pluto.
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Io and Europa Meet Again
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
This beautiful image of the crescents of volcanic Io and more sedate Europa is a combination of two New Horizons images taken March 2, 2007. Io steals the show with its beautiful display of volcanic activity.
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Jupiter's Amazing Moon Io
Credit: NASA/JPL/University of Arizona
This global view of Jupiter's moon, Io, was obtained during the tenth orbit of Jupiter by NASA's Galileo spacecraft on 19 September 1997 at a range of more than 500,000 km (310,000 miles). Io (which is slightly larger than Earth's moon) is the most volcanically active body in the solar system. Colors are enhanced.
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Galileo Views of Io
Credit: NASA/JPL/University of Arizona
Galileo spacecraft observations: a three-color global scale view of Io obtained on 3 July 1999 (Orbit 21) with a resolution of 1.3 km per pixel is shown on the left. The corresponding infrared image on the right was taken at 4.7 μm on October 16 2001 in daytime and has a spatial resolution of 30 km/pixel obtained . The near infrared picture shows the active volcanoes glowing thermal radiation.
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Bright & Young Eruptions on Io
Credit: F. Marchis
Observations of several bright & young eruptions on Jupiter's moon Io detected at short wavelength (~ 2.1 mm) on the top and longer wavelength (~ 3.2 mm) on the bottom since 2004 using the W.M. Keck 10m telescope (May 2004, Aug 2007, Sep 2007, July 2009), the Gemini North 8m Telescope (Aug 2007) and the ESO VLT-Yepun 8m telescope (Feb 2007) and their adaptive optics systems.
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Quiescent Activity of Io 2010 & 2011
Credit: F. Marchis
Quiescent activity of Io observed in 2010 & 2011 showing the several quasi-permanent eruptions in Lp band (at ~3μm) [bottom] and the absence of bright outbursts or young eruptions in K band (at ~2 μm) [top].
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Simulation of Observations of Io
Credit: F. Marchis
Simulation of observations of Io using the W.M. Keck telescope and its current AO system, a next generation AO system mounted on the W.M. Telescope (KNGAO), and the Thirty Meter Telescope (TMT) equipped with its AO system named (NFIRAOS).
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First Global Map of Io, Jupiter's Volcano Moon
Credit: USGS
This first-ever complete map of Jupiter's volcanic moon Io released on March 19, 2012, was created using data and images from NASA's Galileo spacecraft, (which studied Jupiter and its moons between 1995 and 2003) and the Voyager mission in 1979. Color views from Galileo were superimposed on higher-resolution monochrome images. [Full story.]
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Mystery of Io's Atmosphere Solved
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
A composite image of Jupiter's moon Io. Volcanic plumes of gas spew sulfur dioxide hundreds of miles into space, as seen by the New Horizons spacecraft. Such activity accounts for a small chunk of the moon's immediate atmosphere, but eventually freezes and builds up a store of the material.
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Jupiter's Moon Io, Taken by NASA's Galileo Spacecraft
Credit: NASA/JPL/University of Arizona
Io, the most volcanic body in the solar system, is seen in this composite image obtained by NASA's Galileo spacecraft in 1996. The smallest features that can be discerned are 2.5 kilometers in size.
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First Complete Map of Io, Jupiter's Volcanic Moon
Credit: USGS
This first-ever complete map of Jupiter's volcanic moon Io released on March 19, 2012, was created using data and images from NASA's Galileo spacecraft, (which studied Jupiter and its moons between 1995 and 2003) and the Voyager 1 mission in 1979. This merged mosaic (top) served as the primary base map for the geologic map of Io (bottom). [Full story.]
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Io New Map Detail
Credit: USGS
This image shows detail of the USGS map of Jupiter's moon Io, released March 19, 2012.
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First-Ever Global Geologic Map of Jupiter's Moon Io
Credit: USGS
This map, released in March 2012 by the U.S. Geological Survey, is the first ever to chart the Jupiter moon Io's geology on a global scale. Io is the most volcanically active object in the solar system. [Full story.]
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Jupiter and Io, by New Horizons
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Goddard Space Flight Center
This montage of New Horizons images shows Jupiter and its volcanic moon Io, and were taken during the spacecraft's Jupiter flyby in early 2007.
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Volcanic Moon of Jupiter Is Smelly and Bizarre
Credit: The Galileo Project, JPL, NASA
The Galileo spacecraft orbiting Jupiter returned these photographs of the Jovian volcanic moon Io in 1996. The red material on the surface is thought to be associated with recent volcanic eruptions.
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Jupiter's Moon Io and Its Magma Ocea
Credit: Xianzhe Jia (University of Michigan) and Krishan Khurana (UCLA)
Artist's concept of the internal structure of Jupiter's moon Io. A global magma "ocean" (shown in orange) lies beneath a crust 30 to 50 kilometers thick. The rest of Io's mantle is shown in gold, while the moon's core is rendered in silver.
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NASA's New Horizons Spacecraft Sees Jupiter and Io
Credit: NASA/JHU/APL.
NASA's New Horizons snapped this view of Jupiter and its volcanic moon Io in early January 2007.
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Jupiter's Family Portrait
Credit: NASA
This "family portrait," a composite of the Jovian system, includes the edge of Jupiter with its Great Red Spot, and Jupiter's four largest moons, known as the Galilean satellites. From top to bottom, the moons shown are Io, Europa, Ganymede and Callisto.
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Jupiter's Moons: Family Portrait
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
This montage shows the best views of Jupiter's four large and diverse "Galilean" satellites as seen by the Long Range Reconnaissance Imager (LORRI) on the New Horizons spacecraft during its flyby of Jupiter in late February 2007. The four moons are, from left to right: Io, Europa, Ganymede and Callisto. The images have been scaled to represent the true relative sizes of the four moons and are arranged in their order from Jupiter.
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Io in Eclipse
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
This unusual image shows Io glowing in the darkness of Jupiter's shadow. Io's surface is invisible in the darkness, but the image reveals glowing hot lava, auroral displays in Io's tenuous atmosphere and volcanic plumes across the moon.
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Io in Eclipse, Again
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute
In the darkness, only glowing hot lava, auroral displays in Io's tenuous atmosphere and the moon's volcanic plumes are visible. The brightest points of light in the image are the glow of incandescent lava at several active volcanoes. The three brightest volcanoes south of the equator are, from left to right, Pele, Reiden and Marduk. North of the equator, near the disk center, a previously unknown volcano near 22 degrees north, 233 degrees west glows brightly.
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Io Creates Spots on Jupiter
Credit: LPAP/Université de Liège
Hubble Space Telescope ultraviolet image of the northern pole of Jupiter. Among many other auroral structures, the Io footprint is the most equator-ward feature close to the centre of the image. This spot is always located close to the feet of the magnetic field lines connected to the satellite Io.
















































