Volcanoes
on the surface of Jupiter’s moon Io
spout plumes of material up to 180 miles (290 kilometers) high in this view
from a NASA probe.
The New
Horizons spacecraft took this view, the best view to date of the Io, last week
during a Jupiter
flyby as the probe makes its way towards Pluto [earlier
image].
[Click
here to read about the successful flyby.]
New
Horizons used its Long Range Reconnaissance Imager (LORRI) camera to take this
view of Io on Feb. 28, 2007, when the probe made its closest
pass by Jupiter.
The
spacecraft took this view, in which one pixel is about 7.4 miles (12
kilometers), from a distance of about 1.5 million miles (2.5 million kilometers).
Io’s Tvastar
volcano, spouting 180 miles (290 kilometers) above the moon’s surface, is
the most prominent feature in this view as it erupts from the 11 o’clock
position near the satellite’s north pole. The plume’s filamentary structure is
detailed with remarkable clarity in the image.
A smaller, symmetrical
fountain of material can also be seen erupting from Io’s Prometheus volcano at
the left (or 9 o’clock region) in this vantage point. The plume is smaller than
Tvashtar’s, peaking at about 40 miles (60 kilometers) above Io.
The top of
still a third plume, from Io’s Masubi volcano, has risen high enough to reflect
light from the setting Sun on the moon’s
night side. It appears as a bright patch near the bottom of the image. A series
of Mt. Everest-sized mountains are also illuminated by the setting Sun along Io’s
terminator boundary line between day and night.
-- Tariq Malik
Credit: NASA/JHU/APL/SwRI.
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