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Ganymede - The Moon Dwarfing Mercury

Did you know that a day on one of Jupiter's moons is a whole week on earth?

Hello! My name is Rafeef, and today I am going to talk to you all about Jupiter's giant moon, Ganymede. To begin with, it is named after the cupbearer of the Olympian gods, a beautiful young boy who was carried to Olympus by Zeus, also known as Jupiter in Roman terms. It has a radius of about 1635 miles, making it the largest moon in our solar system, in addition to being larger than Mercury!
Discovery and Formation

Ganymede was discovered by Italian astronomer Galileo Galilei on January 7, 1610. The discovery of this moon, along with three others, marked the discovery of the first moons that orbit planets other than Earth. This was significant to our astronomical history; it led us to the realization that the planets in our solar system orbit the sun rather than the Earth being the center of attention.

It is believed that Ganymede was formed from the leftovers of the dusky disk from Jupiter's formation. But how could leftover dust be the cause of the formation of such a large moon? Let us explain.

Hubble finds evidence of water vapour on Jupiter’s moon Ganymede. (2021, July 27). The Indian Express.

Research, detailed in paper and accepted to the Astrophysical Journal, proposes a new method for planet and moon formation: pebble accretion.

Thus, the initial moon seeds, which were formed from the dust, were gravitationally captured by a disk of gas that surrounded the infant planet. Over the course of the next few million years, the seed grew in size, all the while moving closer to Jupiter, until it formed the moons that we know today.

Ganymede: A Suitable Habitat For Humans?

A model created in 2014 of Ganymede's interior suggested that, indeed, Ganymede may be suitable for primitive life forms to survive on its surface. The icy rock bottom of Ganymede's sea (Ganymede might have more water than there is on Earth!) may be in contact with sea water, according to the model. Furthermore, by analyzing the data from the NASA/ESA Hubble Space Telescope, it shows that the first evidence of water vapor from a place other than Earth came from Ganymede itself!

I hope you enjoyed reading it as much as I enjoyed writing it, and made use of all this information! I've had a love for astronomy since I was a child, in addition to Greek mythology, which is where the name Ganymede comes from.

Rafeef A

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