Word: spacecraft
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...Mars Phoenix is just the latest in a small fleet of relatively inexpensive spacecraft (a few hundred million dollars apiece, which is tag-sale prices by spaceship standards) NASA has launched toward Mars in the last dozen years. The Mars Express and Mars Odyssey orbiters have done the true yeoman's work, extensively mapping the planet from high overhead. The Sojourner, Spirit and Opportunity rovers have made the headlines, toddling around in the soil of the Red Planet and sending back portfolios of pictures. But it's Phoenix that could make the most thrilling discoveries...
...tougher than the powdery soil found at lower Martian latitudes. The scoop will be able to dig about 19 in. deep (.5 m), or about the depth at which NASA scientists believe the ice meets the soil. It will then transfer what it gouges out to the spacecraft itself, where the onboard science lab will examine it for organic materials, biochemical processes and other signs of life...
...orbiter's plume dive was responsible for some of that shifting. Passing just 120 miles (190 km) above the surface of Enceladus, Cassini sampled an icy exhaust that researchers didn't even know existed until the spacecraft spotted it three years ago. NASA expects to release detailed composition information soon, but the ice hints at subsurface water and the attendant possibility of life. Seven more close-brush flybys are in the offing, including one high-wire plunge that will drop the spacecraft a scant 15 miles (24 km) above Enceladus' surface. Says JPL's Spilker: "We're going to taste...
Before the orbiter attempts that maneuver, it will execute two flybys of the moon Titan, whose opaque orange atmosphere has been increasingly pierced by the spacecraft's radar. And this summer Cassini will make an unusually high orbit above Saturn's massive B ring, promising unique images of the ring, spread like an immense halo around the planet. The ship will also have the rare opportunity to observe the sun cross the plane of the ring from south to north, literally shedding light on the B ring's complex particle structure. "We want to know what a particle would look...
Less glamorous but more sweeping than the half-year Phoenix mission was the long-running Ulysses mission, which took the first full measure of the sun's polar regions. If it swirls, floats or emanates near the sun, Ulysses studied it. The spacecraft discovered that the sun's magnetic field determines the regions that produce the solar wind, and ruffled more than a few scientists' feathers when it showed that a hot corona produces the fastest solar winds--exactly the opposite of prevailing theories...