NASA Cassini Image: Prometheus practices its pull

NASA Cassini Image shows Shepherd moon Prometheus hovering just inside the reflective F ring. 

Credit: NASA /JPL-Caltech /Space Science Institute.

Lit by eerie, reflected light from Saturn's F ring (and a casting a faint shadow through a haze of icy "mist") Saturn's moon Prometheus can be seen in the raw image above, captured by Cassini's narrow-angle camera on Feb. 5 from a distance of 667,596 miles (1,074,392 km).

It's also receiving some light reflected off Saturn, which is off frame at the top (where the outermost edge of the A ring and the Keeler gap can be seen.)

As the potato-shaped Prometheus approaches the ring it yanks fine, icy material in towards itself, temporarily stretching the bright particles into long streamers and gaps and even kicking up bright clumps in the ring. It's a visual demonstration of gravity at work.

At its longest Prometheus is about 92 miles (148 km) across, but only 42 miles (68 km) in width.

It circles Saturn in a wave-shaped, scalloping orbit once every 14.7 hours.

NASA's New Orion Spacecraft: Astronauts Practice Launching

Astronauts Rick Linnehan and Mike Foreman try out a prototype display and control system inside an Orion spacecraft mockup at Johnson Space Center during the first ascent and abort simulations for the program. 

Image Credit: NASA

NASA astronauts recently experienced what it will be like to launch into space aboard the new Orion spacecraft during the first ascent simulations since the space shuttles and their simulators were retired.

Ascent simulations are precise rehearsals of the steps a spacecraft's crew will be responsible for - including things that could go wrong - during their climb into space.

They can be generic and apply to any future deep space mission, or very specific to a launch that's been planned down to the second.

Rick Linnehan

For now, Orion's simulations fall into the first category, but practicing now helps ensure the team will have the systems perfected for the astronauts in any future mission scenario.

"Simulations like these provide valuable experience by giving astronauts and our operations team an early look at what going to deep space in Orion will be like," said Lee Morin, an astronaut and supervisor of Johnson's rapid prototyping laboratory, who has been working on the Orion displays.

Lee Morin

"Rehearsing launch and ascent--two of the most challenging parts of Orion's mission -- also gives us an opportunity to work toward optimizing how the crew interacts with the spacecraft."

Designing a spacecraft's cockpit for ease of use and efficiency is no easy task. Each space shuttle had 10 display screens, more than 1,200 switches, dials and gauges, plus hundreds of pounds of procedures printed on paper.

Mike Foreman

Orion, which is designed for deep-space exploration and autonomous or piloted rendezvous and docking, will use new technology to distill all of that down to just three computer screens, each the size of a sheet of paper.

"It sounds promising and saves a lot of weight, but designing it is challenging," said Jeff Fox, the Orion crew systems integration lead.

"We don't want the crew to have to search through a lot of dropdown menus when they need to quickly access key systems and information."

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