The solar system's largest moon, Ganymede, is captured here alongside the planet Jupiter in this picture taken by NASA's Cassini spacecraft, December 3, 2000. Ganymede is larger than the planets Mercury and Pluto and Saturn's largest moon, Titan. Both Ganymede and Titan have greater surface area than the entire Eurasian continent on our planet. Cassini was 26.5 million kilometers (16.5 million miles) from Ganymede when this image was taken. The smallest visible features are about 160 kilometers (about 100 miles) across. (Photo courtesy of NASA/Newsmakers - Getty Images)

A recent news story suggests that planetary scientists believe that one of the moons orbiting Jupiter may have more water than earth and could support some life form.

Facts About Ganymede

Ganymede is just one of Jupiter’s 63 moons. In addition to being the largest moon in our solar system it’s also the only known moon with it’s own magnetic field.

Information from the Hubble telescope has fostered a belief that Ganymede is somewhat like a “Dagwood sandwich.”

That is many layers are present and one or more of those layers is an ocean about 60 miles deep comprised of salt water beneath a crust of mostly ice. Estimates are that there is ten times more water than exists on earth.

There is the assumption that if there is water then some form of life might be possible in spite of the hostile surface conditions.

Other Fun Facts About Jupiter

  • Jupiter is big. It’s 2.5 times the mass of all other planets combined. Three hundred eighteen times bigger than earth.
  • If Jupiter got bigger it would actually get smaller. Huh? Any additional mass would cause the planet to collapse in on itself making it four times denser but about the same size or smaller. Makes sense right??
  • It only takes a little less than ten hours for Jupiter to make one revolution. The fast speed has caused it to flatten on top and be fatter at the equator. Its speed causes a very powerful magnetic field. No problem finding North with your compass there.
  • Jupiter’s spinning speed also causes dangerous radiation and would probably prohibit any manned landing with current space technology. We would need those James T. Kirk radiation shields on the Starship Enterprise.
  • Jupiter’s Red Spot. Giovanni Cassini was the first to mention this huge spot on Jupiter’s surface in 1665. It measured about 24,000 miles wide one hundred years ago. Three hundred plus years later it’s about half the size it was. Many speculate it’s a huge hurricane on the planet’s surface. It’s anyone’s guess when or if it will ever end. Trying to imagine Katrina lasting 350 years.

Some Final Thoughts

It only takes a few facts about space for us to see how miniscule we are in the vast reaches of space.

We marvel at the amazing things on our own planet but many of those marvels are dwarfed when compared to the physics of our solar system.

I think we would all like to believe that we are not alone in the universe. But our movies and TV shows always portray any terrestrial visitors as invaders or here to wipe us out.

As Will Smith remarked in the movie, Independence Day, “I don’t think they flew a billion light years to come down here and start a fight.”

We all know how well that observation turned out.

If there is life in the ocean on Ganymede that would be cool to know but bringing it back here probably not a good idea.