March 4, 2019 - Voyager Versus the Volcano

Voyager Versus the Volcano A few days after its closest approach to Jupiter, the Voyager 1 spacecraft glanced back over its shoulder and captured a routine image of Io, the innermost of Jupiter’s four largest moons. That image, taken 40 years ago this week, was processed by Voyager navigation team member Linda Morabito, who noticed a rather large cloud near the moon’s limb. Further analysis revealed that the mysterious object was actually the giant plume of a volcano—the first active volcano discovered anywhere beyond Earth. The Voyager and Galileo spacecraft have shown Io to be awash in active volcanoes—more than any other world in the solar system. In this Galileo image, taken in February 2000, newly erupted hot lava is seen in the Tvashtar Catena chain of volcanic calderas.

Image credit: NASA / JPL-Caltech

Weekly Calendar

March 4 - 10, 2019

Holidays - Sky Events - Space History

Monday 4

Moon at apogee
Pallas appears stationary

1979: Jupiter’s rings discovered
1994: STS-62 Columbia launched

Tuesday 5

Mercury appears stationary

1512: Gerardus Mercator born
1978: Landsat 3 launched
1979: Voyager 1 flies by Jupiter
1982: Venera 14 lands on Venus, returns color photos of Venus’s surface