News from NASA on July 26, 2021 For the first time, astronomers have uncovered evidence of water vapor in the atmosphere of Jupiter’s moon Ganymede, the largest moon in the Solar System. This water vapor forms when ice from the moon’s surface sublimates — that is, turns from solid to gas. Astronomers re-examined Hubble observations from…
Tag: Ganymede
Here’s Our First Close-up Image of Ganymede in Over Two Decades!
The image data are starting to come in from NASA’s Juno spacecraft and if this is any indication, they’re going to be gorgeous! On Monday, June 7, 2021 the Jupiter-orbiting spacecraft passed within just over 1000 kilometers of Ganymede. This is the closest any spacecraft has come to the Solar System’s largest moon since May…
Ganymede’s Polar Ice is ‘Disrupted’ by Jupiter’s Plasma
The first-ever infrared images of Ganymede’s north pole, taken on December 26, 2019 with the JIRAM instrument aboard NASA’s Juno spacecraft, show that the gigantic moon’s polar ice lacks any crystalline structure like the water ice we’re familiar with typically does here on Earth. This is a result of constant bombardment by charged plasma in…
Ganymede’s Aurorae Hint at an Ocean Ten Times Deeper than Earth’s
It’s long been suspected that Jupiter’s giant moon Ganymede may harbor a subsurface ocean of liquid water beneath its icy yet hard-as-rock crust, and now some ingenious observations with the Hubble Space Telescope are making an even more convincing case for it!
When a Comet Met Ganymede
Captured by NASA’s Galileo spacecraft on April 5, 1997, this image shows Enki Catena, a 161.3-km (100-mile) long crater chain on the surface of Jupiter’s moon Ganymede. Named after the Sumerian god of fresh water, Enki Catena is thought to have been formed when a comet approached too close to Jupiter and was torn into 13 pieces, each impacting Ganymede in…
Ganymede Gets a Little Geologic Love
We don’t get to hear a lot about Ganymede these days, what with everyone paying so much attention to Titan and Enceladus and Europa and several other moons out there. Which is too bad because 1. Ganymede is plenty fascinating in its own right; and 2. it’s the LARGEST MOON IN THE SOLAR SYSTEM (and…
A Giant Among Moons
Our solar system’s largest moon, Ganymede. © Ted Stryk. With so much focus these days on Saturn’s many varied moons, I thought I’d post a beautiful image of Jupiter’s lesser-seen – but anything but lesser-sized – moon, Ganymede. The largest of Jupiter’s 63 named moons – as well as the largest moon in our…
A Giant Among Moons
The largest of Jupiter’s 63 known moons and the largest moon in our solar system, Ganymede has twice the mass of our own moon and is even larger than the planet Mercury. Its surface is marked by dark regions which are full of craters and lighter areas lined with ridges. This image was taken by…
Lights in the Dark 