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…
Search Results for: 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…
Fun Fact: All the Planets in the Solar System Could Fit Between Earth and the Moon
It might seem a bit far-fetched but yes, it’s true: if you could line up all of the other planets in our Solar System in a row edge-to-edge (or more geometrically accurately, limb-to-limb) and for good measure even include Pluto, the entire queue would easily fit within the space between Earth and the Moon. (Not…
Titan is Drifting Away from Saturn Much Faster than We Thought
Recent research using data acquired by NASA’s Cassini spacecraft reveals that Titan is moving away from Saturn at a much faster rate than previously thought. How fast? Read on… “This result brings an important new piece of the puzzle for the highly-debated question of the age of the Saturn system and how its moons formed.”…
New Theory Emerges on the Formation of Jupiter’s Galilean Moons
(From Caltech) During the first few million years of our sun’s lifetime it was surrounded by a protoplanetary disk made up of gas and dust. Jupiter coalesced from this disk and became encircled by its own disk of satellite-building material. This “circum-Jovian disk” was fed by material from the sun’s protoplanetary disk that rained down…
Meet Metis – Jupiter’s Closest, Quickest Moon
Everyone’s heard of Jupiter’s four most famous moons Europa, Io, Callisto, and Ganymede—we’ve known about them for over 400 years, thanks to Galileo—but giant Jupiter has many more moons than that. To date there are thought to be 79 natural satellites orbiting Jupiter. So you’d be forgiven for not being immediately familiar with all of…
OSIRIS-REx Captures a Picture of Jupiter from L4
NASA’s OSIRIS-REx may be designed to study asteroids close up but recently it’s captured a view of something farther away and much, much larger: the giant planet Jupiter and three of its largest moons at a distance of over 400 million miles! The image was taken on Feb. 12, 2017, when the spacecraft was 76 million…
Eppur Si Muove: Galileo’s Big Night, 407 Years Ago Today
407 years ago tonight, on January 7, 1610, the Pisan astronomer Galileo Galilei looked up at a brilliantly-shining Jupiter through his own handmade telescope and saw three bright little “stars” next to it, stirring his natural scientific curiosity. Further observations over the next several nights showed that the planet wasn’t moving relative to the little “stars” as it…
Lights in the Dark 