The Galilean Moons

In the year 1610, it was commonly believed that the Earth was the center of the Universe, that all bodies rotated around the perfect planet, placed by god with the heavens around it.  Galileo Galilei dealt a major blow to this idea, by using an early telescope to improve his vision and look up at some surprising dots. These dots formed a line that went straight through the bright planet Jupiter.  As Galileo looked again and again, night after night, he noticed that they not only persisted, they moved.  Their motion was predictable, and Galileo realized that they were orbiting Jupiter, just...

Europa Chemistry

I always get giddy when talking about Europa, as many astronomers do.  It’s one of the most fascinating places in our solar system when it comes to the search for life.  It has lots of water, likely contained in a subsurface ocean.  It’s heated though a gravitational tug of war with Jupiter and the other Galilean moons.  And, as of recently, it has a chemical production system that matches Earth’s. I wonder what goes on beneath the thick ice of Europa.  Is there an ecosystem filled with alien life down there?  Life in Earth’s oceans feels very alien, but creatures from...

1000 Things You Didn’t Know About The Universe #6: Earth’s Moon is Big

When we see the Earth’s only Moon up in the sky, we often think about how small it is.  It’s only about 1/4 the diameter of the Earth, and at a distance of 384,000 Km, it looks small in the sky.  But often size is entirely a matter of perspective.  What we compare something to, that’s what determines it’s size.  When the Moon is high in the sky we easily compare it to the size of the window we are looking through, or to a nearby tree, or our outstretched hand.  All of this can make the Moon seem pretty tiny....

Even More Visions of the Future

You’ve seen the planets, now let’s look at some of the best moons to visit in the solar system, ala the romanticized art deco style! Ceres is like a gas station for that long trip to Jupiter, treated as an icy rock that is not the best tourist destination.  Enceladus is a lot like the spacefarer’s version of Yellowstone park, with the southern hemisphere geysers being the appeal. My two favourites are Titan and Europa.  Titan’s colour scheme and view of Saturn are gorgeous, but the best part is the paddle boats in the hydrocarbon seas.  The most interesting visit...

Tiny Spacecraft are the Future!

For a long time, the scientific community has been hopeful for a mission to some of the most interesting moons of the solar system.  Europa, Enceladus, and Ganymede all have subsurface oceans and will give substantial insights into the formation and evolution of life in the solar system and beyond. The only problem is that it costs an astronomical (literally) amount of money to get there.  A bare bones mission to Europa would cost over 600 Million dollars, and if we are spending that much we had better be sure it will work. Money aside, the technology to get appropriate...

A Song to laugh about the 176 Moons of the Solar System

About a year ago I had an idea for a music video.  I wanted to take a concept in science and put it to music, making it funny, catchy, memorable, and educational.  I wrote out the majority of the lyrics but left it alone for a few months, until I connected with the right friend.  My good friend Bob Wegner is a very talented guitarist and audio engineer, and as we spoke about the idea he wanted to be the guy to record it.  We spent an afternoon doing the vocals and guitars, and he cleaned it up and made...

Another Liquid Ocean on a Moon? Time for Ganymede to Shine!

After reaching a deeper understanding of the subsurface ocean of Enceladus just yesterday, a stunning discovery has just been made about the largest Moon in the solar system.  The largest moon of Jupiter, Ganymede, contains a subsurface ocean of it’s own.  The discovery was made with the Hubble space telescope and a careful study of aurora on the giant moon. That’s right Ganymede has auroral activity.  This is because it is the only moon in the solar system with a magnetic field.  The magnetic field funnels radiation from the Sun toward the north and south poles, where it ionizes molecules...

Enceladus has Hydrothermal Activity Beneath a Liquid Ocean

Some of the moons of gas giant planets have a unique property: They are worlds that have a source of heat other than the Sun.  The huge tidal forces imparted by their host planet and fellow moons cause their crust to grow and shrink, creating huge friction and heating the rock.  It means that even if these moons are far from the warmth of the Sun, they can still host liquid water.  There are two moons in our own solar system that are especially enticing: Jupiter’s second moon Europa, and the icy moon of Saturn known as Enceladus.  Each host...

Jupiter’s Triple Moon Eclipse and Ceres Comes Into View

There has been a lot to talk about with our home solar system lately.  Spacecraft approaching dwarf planets, robots on Mars, and all kinds of orbiters giving new insights and views we had never expected.  It’s a heavy news year for Planetary Science, and the great stories keep creeping up! Today we have an update on the Dawn spacecraft approaching Ceres.  The picture I posted on January 20th  (shown below) was from 380,000 Km away, comparable to the distance between Earth and the Moon. Now, about 2 weeks later, Dawn is only 145,000 Km away, and the view is much clearer!...