First discovered by Galileo back in 1610, Ganymede is the largest moon of our solar system and the only planetary satellite in the solar system to have its own magnetosphere – an area in space surrounding an astronomical object with charged particles that are controlled by the body’s magnetic field. Orbiting Jupiter, Ganymede itself is larger than either the planet of Mercury or the dwarf planet Pluto. With a diameter of more than three thousand miles, this large moon has been a curiosity of ours for more than 400 years. A dark and icy world, there is little we know about it save for its two distinct regions: one dark and crater covered and another that is lighter and defined more by its many grooves and ridges. Now, Ganymede becomes the fourth moon of our solar system to be fully mapped out, joining our own moon as well as Jupiter’s Io and Callisto.
A research team led by Wes Patterson of the John Hopkins Applied Physics Laboratory and Geoffrey Collins of Wheaton College, Norton, Massachusetts has created the first global geologic map of Ganymede. This makes it not only the fourth mapped out moon of our solar system, but also the first complete map of an icy, outer-planet moon. Their map details many geological features of Ganymede that have formed over much of our solar system’s history, making it a prime source of astrological exploration. These features also record evidence of the moon’s evolution of the small bodies that have impacted Ganymede’s surface over the many millions of years since its formation. Thanks to its size, this make Ganymede a prime source of observation, as there are so many different locations to chose from. By studying it, scientists are able to make educated assumptions regarding other icy satellites with features similar to Ganymede. According to Collins, “Ganymede also shows features that are ancient alongside much more recently formed features, adding historical diversity in addition to geographic diversity,” which in turn will make it a great source of study for many years to come.
Curious? You can see the Ganymede map for yourselves here. I highly recommend checking it out.
As many of your know by now, I love learning more and more about what goes on out beyond our atmosphere. Space has always held a deep fascination for me, as it has for many. So many people view it as a recognition of our insignificance in the cosmos, but I disagree. Rather than see us as insignificant next to the vastness of space, I see us as – thus far – unique. So much exists out there, yet so far we have been hard pressed to find any signs of life anywhere else in the galaxy. Given that, how can the more we learn about other planets and moons not reinforce just how amazing it is to be human?
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