All these Worlds…

In Arthur C. Clark’s novel, 2010, the story ends with a warning to humans ready to explore the Jovian moons: “All these worlds are yours — except Europa. Attempt no landings there.” In the next book, we learn that life has made a foothold on this icy-looking world.

Science fiction or science fact? It is possible that life could exist in water oceans beneath the thin ice crust of this little moon. Is it probable? We don’t know.

Conamara Chaos on Europa

The Voyager and Galileo missions have mapped this world extensively, studying its icy surface. In the image shown here (taken by the Galileo spacecraft’s cameras), we see an area on Europa called the Conamara region. It is basically a frozen set of “ice rafts” created when large blocks of ice were disrupted during an impact. After the ripples from the crash died down, these “rafts” and criss-crossed cracks froze into place on the little moon’s surface. This event formed a crater Pwyll, which lies 1000 kilometers (640 miles) away.

Beneath this jumbled icy terrain lies an ocean of what is probably slushy ice water. At the core of this tiny world, there could be heat — generated by the continual and combined tidal pull of Jupiter on one side of Europa and the outer moons on the other side. If there IS heat at the center of this watery world, it’s possible that life could survive there. But, for now, we don’ t know if there are any Europan life forms colonizing these oceans. That discovery awaits future visits by robotic spacecraft, and eventually — human explorers.

Mission-Specific

Hubble Space Telescope was successfully retrieved by astronaut Nancy Currie who then used the shuttle's remote manipulator arm to set the observatory into place in the shuttle bay.

Let’s take a break from our tour of the planets to visit the astronauts in the space shuttle Columbia. They’re on a mission for the next week to service the Hubble Space Telescope. Over the next few days they’ll be going out in pairs to do things like replace the observatory’s solar arrays, install a new instrument called the Advanced Camera for Surveys, upgrade the computer system, fix the cooling system on the Near-Infrared Camera and Multi-Object Spectrograph (called NICMOS for short), and a few other tasks.
Rather than take up your time with lots of description here, I’ll point you to the NASA TV link for the mission and you can watch for yourself. Most of the repair mission activities begin around 0630 GMT (the wee hours for folks in North America). You can get the latest schedule from this same site. Happy viewing!

Exploring the Solar System: Mars

Mars!

Of all the planets in the Solar System, to my mind, this place rocks! Why do I say that? I’ve always wanted to go there, ever since I was a kid and played “Going to Mars” with my sibs and cousins out in a field by our house. I hadn’t even read any of the Edgar Rice Burroughs Mars books at that time, I just knew it had to be an interesting place!

Fictional Mars was peopled with all manner of strange beings — princesses, heroes, alien beings called Thoats, and they all lived a sort of adventurous life among the canyons and jungles of the imaginary surface of the Red Planet.

All those beings began to dissolve into the fictional plane when telescopes got powerful enough to give us a view of Mars that was more like the Arizona desert than the jungles of Africa. When the first spacecraft missions visited the planet beginning in the 1960s, the world of thoats and princesses vanished back to the bookshelves.

Today, we know Mars is a dry and dusty desert planet, with the remains of ancient lakes and streambeds showing that water once existed on the surface, and two polar caps of water and carbon dioxide ice. Like Earth, it has volcanoes — but its calderas have been sleeping for millennia. It has an atmosphere not much thicker than the Earth’s stratosphere, and its air is mostly carbon dioxide — the same waste product we breathe out as we breathe in oxygen. The surface is split by canyons, pockmarked by impact craters, and covered with fine, wind-blown dust and sand.

Think we’ll ever get to explore this planet in person? For more than thirty years, people have made mission plans to take humans to the Red Planet. The “Case for Mars” meetings (which were held beginning in the early 1980s and have been repeated every few years at the University of Colorado) included many sessions on ways to get to Mars, surviving on its surface, and the many scientific studies that explorers could do. Today the Mars Society and others carry on the legacy of planning — with an eventual goal of putting people on the Red Planet sometime in the next decade (or sooner).

So why do I think this seemingly dead planet rocks? Because of all the planets in the Solar System, Mars is the most like Earth — and offers the best chances for actual human exploration and eventual habitation. It fires our imagination and gives us a place to go next. Understanding how this planet came to be the way it is helps us learn more about the evolution of the solar system as a whole, and our own home planet in particular. Besides, it’s just plain darned cool!