Orion's belt lights up Cassini's view of Enceladus

Oct 19, 2011
Dramatic plumes, both large and small, spray water ice out from many locations along the famed "tiger stripes" near the south pole of Saturn's moon Enceladus.

(PhysOrg.com) -- NASA's Cassini mission will take advantage of the position of two of the three stars in Orion's belt when the spacecraft flies by Saturn's moon Enceladus on Wed., Oct. 19. As the hot, bright stars pass behind the moon's icy jets, Cassini's ultraviolet imaging spectrograph will acquire a two-dimensional view of these dramatic plumes of water vapor and icy material erupting from the moon's southern polar region. This flyby is the mission's first-ever opportunity to probe the jets with two stars simultaneously, a dual stellar occultation.

From Cassini's viewpoint, the closest of Orion's stars will appear about 9 miles (15 kilometers) above the moon's limb, or outer edge. The second star will appear higher, about 19 miles (30 kilometers) from the limb. In the foreground will be Enceladus' icy plumes, which extend hundreds of miles into space.

As the spacecraft passes Enceladus, its infrared instruments, cameras and other instruments will also be monitoring activity on the moon. The orbiter will fly within about 765 miles (1,230 kilometers) of Enceladus' surface.

This will provide researchers with new insight into the jets--their content, the speed at which they are travelling and how they vary. It will also provide new information on the famed "tiger stripes" from which the jets erupt. These fissures in Enceladus' surface are the "nozzles" from which the plumes are propelled at supersonic speeds. Knowing more about their structure may help unlock some of the secrets within Enceladus' interior, including the source of the water-rich plumes.

The celebrated the 14th anniversary of the spacecraft's launch last week.

Having completed its four-year prime mission in 2008, the mission is now on its second extension, the Cassini Solstice Mission. One of the mission's goals is to provide further information on previous Cassini discoveries, such as lakes on Titan and plumes on Enceladus, first detected by Cassini in 2005.

Explore further: Red moon at night; stargazer's delight

Related Stories

Saturn's geyser moon Enceladus shows off for Cassini

Oct 04, 2011

(PhysOrg.com) -- NASA's Cassini spacecraft successfully completed its Oct. 1 flyby of Saturn's moon Enceladus and its jets of water vapor and ice. At its closest approach, the spacecraft flew approximately ...

Cassini finishes sleigh ride by icy moons

Dec 22, 2010

On the heels of a successful close flyby of Saturn's moon Enceladus, NASA's Cassini spacecraft is returning images of Enceladus and the nearby moon Dione.

Cassini Heading to Titan after Tagging Enceladus

May 20, 2010

(PhysOrg.com) -- NASA's Cassini spacecraft is on its way to a flyby of Saturn's largest moon, Titan, after capturing some stunning images of Enceladus. One view shows the hazy outline of Titan behind Saturn's ...

Recommended for you

Astronauts to reveal sobering data on asteroid impacts

5 hours ago

This Earth Day, Tuesday, April 22, three former NASA astronauts will present new evidence that our planet has experienced many more large-scale asteroid impacts over the past decade than previously thought… ...

Rosetta instrument commissioning continues

6 hours ago

We're now in week four of six dedicated to commissioning Rosetta's science instruments after the long hibernation period, with the majority now having completed at least a first initial switch on.

Astronaut salary

6 hours ago

Talk about a high-flying career! Being a government astronaut means you have the chance to go into space and take part in some neat projects—such as going on spacewalks, moving robotic arms and doing science ...

Red moon at night; stargazer's delight

Apr 16, 2014

Monday night's lunar eclipse proved just as delightful as expected to those able to view it. On the East Coast, cloudy skies may have gotten in the way, but at the National Science Foundation's National Optical ...

User comments : 0

More news stories

Cosmologists weigh cosmic filaments and voids

(Phys.org) —Cosmologists have established that much of the stuff of the universe is made of dark matter, a mysterious, invisible substance that can't be directly detected but which exerts a gravitational ...

Hubble image: A cross-section of the universe

An image of a galaxy cluster taken by the NASA/ESA Hubble Space Telescope gives a remarkable cross-section of the Universe, showing objects at different distances and stages in cosmic history. They range ...

Hackathon team's GoogolPlex gives Siri extra powers

(Phys.org) —Four freshmen at the University of Pennsylvania have taken Apple's personal assistant Siri to behave as a graduate-level executive assistant which, when asked, is capable of adjusting the temperature ...

Deadly human pathogen Cryptococcus fully sequenced

Within each strand of DNA lies the blueprint for building an organism, along with the keys to its evolution and survival. These genetic instructions can give valuable insight into why pathogens like Cryptococcus ne ...

Researchers discover target for treating dengue fever

Two recent papers by a University of Colorado School of Medicine researcher and colleagues may help scientists develop treatments or vaccines for Dengue fever, West Nile virus, Yellow fever, Japanese encephalitis and other ...