APOD: 2025 September 1 Б Callisto: Dirty Battered Iceball
Explanation:
Its surface is the most densely cratered in the Solar System -- but what's inside?
Jupiter's moon
Callisto is a battered ball of dirty ice
that is larger than the planet
Mercury.
It was visited by NASA's
Galileo spacecraft in the 1990s and 2000s, but the recently reprocessed
featured
image
is from a flyby of NASA's
Voyager 2 in 1979.
The moon would appear darker if it weren't for the tapestry of light-colored
fractured surface ice created by eons of impacts.
The
interior of Callisto
is potentially even more interesting because therein might lie an internal layer
of liquid water.
This potential
underground sea is a candidate to
harbor life -- similar with sister moons
Europa and
Ganymede.
Callisto is slightly larger than
Luna,
Earth's Moon, but because of its high ice content is slightly less massive.
ESA's
JUICE and NASA's
Europa Clipper missions are now headed
out to Jupiter
to better investigate its
largest moons.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
