Ride along with Rhea

Apr 28, 2011 By Jason Major
Animation made from raw Cassini image data acquired April 25, 2011. Credit: NASA / JPL / Space Science Institute

Assembled from 29 raw images taken by the Cassini orbiter on Monday, April 25, this animation brings us along an orbital ride with Rhea as it crosses Saturn’s nighttime face, the planet’s shadow cast across the ringplane. Sister moons Dione and Tethys travel the opposite lane in the background, eventually appearing to sink into Saturn’s atmosphere.

The exposure varies slightly from frame to frame due to the fact that they are not all taken with the same color channel filter.

(1,528 kilometers, or 949 miles, wide), Dione (1,123 kilometers, or 698 miles wide) and Tethys (1,066 kilometers, or 662 miles wide) are all very similar in composition and appearance. The moons are composed mostly of water ice and rock, each covered in craters of all sizes and crisscrossed by gouges, scarps and chasms. All three are tidally locked with , showing the same face to their parent planet in the same way that the Moon does with Earth.

The Cassini spacecraft was 2,227,878 km (1,384,339 miles) from Rhea when the images were taken.

(The original images have not been validated or calibrated. Validated/calibrated images will be archived with the NASA Planetary Data System in 2012.)

Explore further: NKorea launch pad expansion 'nearing completion'

add to favorites email to friend print save as pdf

Related Stories

Moon Illusion tricks the eye

Jan 19, 2011

We’ve all experienced the Moon Illusion, where our own full Moon looks bigger when seen on the Earth’s horizon. But how about this illusion where you can’t really tell which of these two moons ...

Cassini's Photo Album From a Season of Icy Moons

Dec 07, 2005

Wrapping up a phenomenally successful year of observing Saturn's icy moons, the Cassini mission is releasing a flood of new views of the moons Enceladus, Dione, Rhea, Hyperion and Iapetus.

Nine moons, 62 Hours for (long) weekend warrior

Oct 20, 2010

Taking a long-weekend road trip, NASA's Cassini spacecraft successfully glided near nine Saturnian moons, sending back a stream of raw images as mementos of its adrenaline-fueled expedition. The spacecraft ...

Rhea's Wisps in Color

Feb 28, 2006

Bright, wispy markings stretch across a region of darker terrain on Saturn's moon Rhea. In this extreme false-color view, the roughly north-south fractures occur within strips of material (which appear greenish ...

Rings on the horizon

Jan 26, 2011

The Cassini spacecraft has taken a some recent images of two of Saturn’s most notorious moons, where in both images the planet’s rings serve as a backdrop. Above, Enceladus stands out with its cratered ...

Saturn Moons In Ghostly Specter

Mar 08, 2006

Ghostly details make this dark scene more than just a beautiful grouping of two Saturn moons, with Tethys on the left and Titan on the right.

Recommended for you

NKorea launch pad expansion 'nearing completion'

1 hour ago

A U.S. research institute says construction to upgrade North Korea's main rocket launch pad should be completed by fall, allowing Pyongyang (pyuhng-yahng) to conduct a launch by year's end if it decides to do so.

Mars, Saturn and the claws of Scorpius

7 hours ago

Look up at the night sky this week and you'll find Mars and Saturn together in the west. Mars stands out with its reddish colouring and you might just be able to detect a faint yellow tinge to Saturn. ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

LKD
not rated yet Apr 28, 2011
Interesting that the shadow on the horizon on Rhea doesn't change. Can someone explain that a little for me? Is it because the satellite is moving to give the false impression that the moon is orbiting quickly?