Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
October 22, 1996
Explanation: What caused the cracks in this giant ice-ball?
Jupiter's moon Europa
has smoothest surface in the solar system and is composed mostly
of cracked water-ice. In the above false-colored picture
released last week by the NASA team
in charge of the Galileo mission,
blue hues represent ice plains divided by dirty red and brown
bands of mottled terrain. As the robot Galileo spacecraft orbits
Jupiter, it sends back revealing pictures of Jupiter and
its large moons
including Europa, Io,
Ganymede, and Callisto.
The region of Europa
highlighted above is known as Minos Linea. The cause for many
of the cracks remains unknown but may involve shifting stresses
from gravity and temperature variations. The new Galileo pictures
have increased evidence that liquid oceans may indeed exist
under these giant ice-sheets, a place possibly ripe for the development of life.
Authors & editors:
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC