[Picture credit: NASA]
Two of Saturn’s moons. Dione is the nearer one, and Enceladus is the snowball in the back. They are made of the same material, but obviously Enceladus has much higher reflectivity.

Enceladus has a 314 mile diameter. That means it would just about fit between Phoenix and San Diego.

Dione in the foreground has a diameter of 698 miles, more than twice that of Enceladus. It’s the 15th largest moon in the solar system.

It is boundlessly fascinating to me that we live in an age where we can see the moons of a far-away planet in this detail.


The Dance of Rhea and Dione

Rhea and Dione
[click to enlarge] Credit: NASA JPL Photojournal
A photograph taken by the Cassini space craft orbiting Saturn. Above is the south pole of Saturn’s moon Rhea (about 1,528 kilometers diameter) and in the background the moon Dione (1,123 kilometers diameter), with its southern part covered by Saturn’s rings, seen almost edge on, in front of Dione.

What a time we live in where we can see crystal clear images of moons of Saturn and its rings!

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Book Review: Doctor Who: The Wheel of Ice – by Stephen Baxter

Wheel of IceSome time in the future mankind has started traveling the solar system in earnest. People live in mining colonies on various moons of Saturn. The Wheel of Ice is a ring of manmade materials, ice-bubbles turned into habitats, empty fuel tanks from spaceships converted to living quarters, all tied together in a ring of four kilometers in diameter around the equatorial plane of the (fictional) Saturn moon Mnemosyne, an ice ball of about a kilometer in diameter.

The TARDIS is a spacecraft traveling through time and space, occupied by the Doctor and his companions, Jamie and Zoe. The TARDIS takes its occupants to Mnemosyne for reasons unknown.

They are quickly drawn into the local politics of a mining colony, where the commercial interest of interplanetary corporations don’t always align with the objectives and wishes of the local population. Children born in the colony, who have never seen Earth, don’t always respect the established authority and various conflicts arise. It’s not an easy place to grow up.

To make matters more complicated, an alien entity seems to occupy the moon, creating mysteries that the Doctor and his friends try to unravel. What they find is much more complex, and much more dangerous, than they ever would have expected.

This book of 292 pages is packed with science fiction action. Cool space technology like skin suits and scooters allow youth to just go on weekend outings to other moons of Saturn, like Titan, for instance, and get themselves into trouble. That would be like teenagers going to the moon for a few days here.

There is also a lot of speculation about the rings of Saturn, how they were created, what they are made of, and what it would be like for a spacecraft to approach the rings, be “inside” of them, and possibly mine them.

Along with human science fiction stuff, the plot includes time travel, an alien entity five billion years old, a supernova that created our solar system and earth and everything we know, and much more epic stuff.

While it was enjoyable to read The Wheel of Ice, I felt there was too much packed into it. The story, the background of the characters, the side plots, all seemed too involved, too complex, for such a smallish story, really. Baxter could have built this out to be a much larger work. Or he could have left out some side plots and simplified things. For instance, the Doctor, Jamie and Zoe could have been just members of the colony. They didn’t really have to arrive in the TARDIS from another space and time. That whole thing just confused me.

220px-TARDIS1Of course, TARDIS didn’t mean anything to me because I didn’t know about any other Doctor Who books or television programs, which apparently are an important part of British popular culture. The TARDIS is a Time and Relative Dimension in Space, a craft in the shape of a police box, with an interior that is much larger than its exterior – go figure. Check this link for more information on the TARDIS.

This is not one of the stronger Stephen Baxter works. I would not have recognized it as Baxter, had I not known the author. Maybe it has something to do with being a Doctor Who series book.

Overall however, I enjoyed reading The Wheel of Ice, but I don’t think I’ll continue with the Doctor Who books.

Rating: **