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: Heavy metal frost? A new look at a Venusian mystery

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

How to grip an asteroid

15 minutes ago

For someone like Edward Fouad, a junior at Caltech who has always been interested in robotics and mechanical engineering, it was an ideal project: help develop robotic technology that could one day fly on ...

Image: Comet 67P/Churyumov–Gerasimenko

2 hours ago

It was 45 years ago when astronomer Klim Churyumov and Svetlana Gerasimenko, one of his researchers, unwittingly began a new chapter in the history of space exploration.

Extreme ultraviolet image of a significant solar flare

2 hours ago

The sun emitted a significant solar flare on Oct. 19, 2014, peaking at 1:01 a.m. EDT. NASA's Solar Dynamics Observatory, which is always observing the sun, captured this image of the event in extreme ultraviolet ...

Heavy metal frost? A new look at a Venusian mystery

21 hours ago

Venus is hiding something beneath its brilliant shroud of clouds: a first order mystery about the planet that researchers may be a little closer to solving because of a new re-analysis of twenty-year-old ...

User comments : 0