Mars

There once were two planets, new to the galaxy and inexperienced in life. Like fraternal twins, they were born at the same time, about four and a half billion years ago, and took roughly the same shape. Both were blistered with volcanoes and etched with watercourses; both circled the same yellow dwarf star—close enough to be warmed by it, but not so close as to be blasted to a cinder. Had an alien astronomer swivelled his telescope toward them in those days, he might have found them equally promising—nurseries in the making. They were large enough to hold their gases close, swaddling themselves in atmosphere; small enough to stay solid, never swelling into gaseous giants. They were "Goldilocks planets," our own astronomers would say: just right for life.

Which leads us neatly onto the Rutherford Appleton Laboratory in the UK, which has devised a "mini magnetosphere" that essentially recreates the protection provided by the Earth's magnetic field. The scientists have so far used the magnetosphere to protect a scale spacecraft from radiation, and they're now working on a concept spacecraft, called Discovery, with a full-scale magnetosphere that could theoretically take humans to Mars.

"Opportunity has driven farther than any other wheeled vehicle on another world," said Mars Exploration Rover Project Manager John Callas, of NASA's Jet Propulsion Laboratory in Pasadena, California. "This is so remarkable considering Opportunity was intended to drive about one kilometer and was never designed for distance. But what is really important is not how many miles the rover has racked up, but how much exploration and discovery we have accomplished over that distance."

A drive of 157 feet (48 meters) on July 27 put Opportunity's total odometry at 25.01 miles (40.25 kilometers). This month's driving brought the rover southward along the western rim of Endeavour Crater. The rover had driven more than 20 miles (32 kilometers) before arriving at Endeavour Crater in 2011, where it has examined outcrops on the crater's rim containing clay and sulfate-bearing minerals. The sites are yielding evidence of ancient environments with less acidic water than those examined at Opportunity's landing site.

As the spacecraft passes close to Phobos, it will be pulled slightly off course by the moon's gravity, by a few tens of centimetres. This small deviation will be measured using the spacecraft's radio signals, and then translated into measurements of gravity, mass and density at different locations on the moon.

"We have found a habitable environment," said John Grotzinger, project scientist for the Curiosity mission. "The water that was here was so benign and supportive of life that if a human had been on the planet back then, they could drink it."

The concept of an Interplanetary Internet first came into being in 1998, about a year after the quarter-century anniversary of the design of the Internet. At the time, a man named Vint Cerf was ruminating on the future of the Internet, and with good reason; Cerf co-developed the Internet protocol suite, a set of rules (commonly known as TCP/IP) that helps orchestrate the transfer of data throughout the network of devices we call the Internet.