“Houston, We Have Geology”

Pluto Lives!

The latest image from Pluto is showing distinct features on the planet's surface. NASA-JHUAPL-SWRI
The latest image from Pluto is showing distinct features on the planet’s surface. NASA-JHUAPL-SWRI
An annotated version of the Pluto image at left.  NASA. The reference globe shows that we are looking roughly at Pluto's north pole at the top left, and the dark regions are along the equator. NASA-JHUAPL-SWRI
An annotated version of the Pluto image above.
NASA. The reference globe shows that we are looking roughly at Pluto’s north pole at the top left, and the dark regions are along the equator. NASA-JHUAPL-SWRI

The world is waking up to a vision of Pluto that now tells us this planet is a dynamic place — not a frozen desert, but a world with landscapes that are still just enough out of focus that it’s tough to tell exactly what they are. According to Alan Stern, the features in this image are indicative of something quite exciting. There appear to be complex surface structures pictured in this new image sent back by New Horizons just yesterday. “In this new image are what appear to be polygonal features, a complex band of terrain stretching east-northeast across the planet, approximately 1,000 miles long; and a complex region where bright terrains meet the dark terrains of the whale,” he said. “After nine and a half years in flight, Pluto is well worth the wait.”

The shapes we’re seeing on Pluto indicate some kind of geological activity, although the details are (forgive me) still a bit fuzzy. There are a number of things that can make these shapes you see on the icy surface. Think about what it looks like as ice and snow melt (sublimate) here on Earth. If you have a dirty snowbank, for example, the snow can melt preferentially, leaving strange shapes behind. On Pluto, there are mixtures of ice on the surface, and they all react a little differently to solar heating and UV light. Also, if you have a heated bit of ground on Earth, snow melts preferentially over that (and also refreezes when temperatures drop).

I honestly don’t know what’s doing the shaping of Pluto’s surface, but it’s a dynamic process (meaning it’s happening in real time). If that truly bears out, and we should know more soon, then Pluto is very  much a “living” world, perhaps in much the same way that Triton at Neptune continues to spew geysers from beneath its surface, or Enceladus at Saturn does the same thing. The big questions now are: what’s causing these surface features, and what’s causing that process? Stay tuned!

Exciting Times in the Solar System

We Are Exploring Many Worlds

It's coming closer!
It’s coming closer!
A side-by-side comparison of Charon (left) and Pluto (right). This is based on an image from the New Horizons site, http://pluto.jhuapl.edu/ and the image has been slightly sharpened and brightened (and recomposed for comparison purposes) by CCP.
A side-by-side comparison of Charon (left) and Pluto (right). This is based on an image from the New Horizons site, http://pluto.jhuapl.edu/ and the image has been slightly sharpened and brightened (and recomposed for comparison purposes) by CCP.

While New Horizons is grabbing the headlines these days for its upcoming flyby of Pluto, there are other fascinating solar system expeditions taking place. Just to give you a quick rundown, world by world:

The Sun: Our star is a fascinating place, and there are a number of missions looking at it from space. The Advanced Composition Explorer (ACE), Global Geospace Geoscience Wind satellite, Hinode, PICARD (from the French space agency, CNES), Ramaty High Energy Solar Spectroscopic Imager (RHESSI), the Solar and Heliospheric Observatory (SOHO), Solar Dynamics Observatory (SDO), the Solar Terrestrial Relations Observatory (STEREO), and Solar Monitoring Observatory (on the ISS).

Earth’s Moon: China’s Chang’e 3 landed a rover that can’t move but is still “live”, the Lunar Reconnaissance Orbiter is orbiting the Moon.

Mars:  Not only do we still have two working rovers on the surface, Curiosity and Opportunity, but we also have the MAVEN orbiter (sampling the atmosphere and determining the climate history), the Indian Space Research Organization’s MOM orbiter, the Mars Reconnaissance Orbiter, Mars Odyssey, and Mars Express (from the European Space Agency);

Venus: Japan’s Akatsuki will return to the planet this autumn.

Ceres: NASA’s Dawn mission is currently circling dwarf planet Ceres, mapping and studying the surface.

Comet 67P: The Rosetta mission (sent by the European Space Agency) is circling the comet as it nears the closest point to the Sun and will follow along as the comet heads back out to deep interplanetary space. Its Philae lander is on the surface, periodically in contact with the mother ship.

Saturn: the Cassini Solstice mission is at Saturn, heading into the final stages of  its long-term mission to the ringed planet.

These are just the current missions. Of course, Earth is constantly studied by spacecraft missions from NASA, ESA, and other space agencies such as JAXA in Japan. It’s a planet, too, and just as important to study as any other world in the solar system.

There are many new missions coming up, more to the Moon, to Mars, and Jupiter. None for the outer solar system — yet. It’s an exciting time to be looking at worlds “first hand” through the eyes of our missions.