The Darwin Mission

By Alex Tilley,

Kyle O’Brien,

and Penny Wu

Vital Stats

• Fourteenth moon from Saturn • Sixth largest• Discovered in 1789 by

William Herschel• 550 km diameter• Located in the densest part of

Saturn’s E ring• Mass is 1.8*10^-5 of Earth• Average Density is 1.61 g/cm³• Escape velocity of 0.239 km/s

http://upload.wikimedia.org/wikipedia/commons/f/f4/Enceladus_moon_to_scale-PIA07724.jpg

Relationships

• It has a mean motion orbital resonance with Dione of 2:1 which is most likely responsible for its tidal heating

• It is most likely the creator of Saturn’s E ring

• It provides oxygen to Titan’s atmosphere

• There is an electrical connection between Saturn and Enceladus

http://blogs.discovermagazine.com/badastronomy/2010/02/23/enceladus-is-erupting/

The Surface

• The surface is made of ice• It has an average albedo of

1.4• There is a large variety of

surface types ranging from very smooth to laden with craters

• The southern polar region has long lines of geysers known colloquially as ‘tiger stripes’

http://upload.wikimedia.org/wikipedia/commons/5/5f/Enceladusstripes_cassini.jpg

http://upload.wikimedia.org/wikipedia/commons/e/ea/Enceladus_June_2008_PIA08417.jpg

Craters

• The oldest craters are thought to be over 4 billion years old and reside in the heavily cratered areas

• The smallest and youngest craters are found in the southern polar region.

• The wide variety of craters indicate possible ongoing geologic activity

http://upload.wikimedia.org/wikipedia/en/0/07/EN004_Painting_on_the_walls.jpg

Tiger Stripes

• They are located in the southern polar region

• The plumes being ejected from the surface come from these stripes

• The space between them is 10% brighter than the rest of Enceladus

http://apod.nasa.gov/apod/ap060310.html

Plumes

• The material is made of water vapor, hydrocarbons, and other elements.

• The material that escapes the atmosphere becomes Saturn’s E ring

• Sources are either sublimating ice or boiling water

http://www.trekmovie.com/images/sciencesaturday/022610enceladus.jpg

Pioneer 11

• Launched April 1973• Surveyed Saturn Sept 1979• Took the first close-up pictures of

Saturn• Mapped magnetic field of Saturn• Measured the temperatures of

Saturn’s and Titan’s atmospheres• Survey the environment of the ring

plane• Discovered two of Saturn’s smaller

moons• Extensively imaged Saturn’s rings

http://quest.nasa.gov/sso/cool/pioneer10/graphics/lasher/slide2lg.gif

Voyager 1 & 2

• Voyager 1 Reached Saturn in November, 1980

• Voyager 2 in August, 1981• Fly-by missions to better

image the rings of Saturn• Discovered Prometheus and

Pandora• Paved the way for the

Cassini mission• Revealed half and half

terrain of Enceladushttp://nssdc.gsfc.nasa.gov/imgcat/hires/vg2_4400428.gif

Cassini

• Present Mission• Sent Huygens probe to surface

of Titan• Discovered atmosphere on

Enceladus• Confirmed geologic activity on• Discovered “Yellowstone-like”

geysers• Determined that Enceladus

“rolled-over”• Discovered electrical

connection between Saturn and Enceladus

http://saturn.jpl.nasa.gov/photos/imagedetails/?imageid=3344

More Questions

• Answer the following questions:– What is the driving force

behind the geologic activity (tectonics)?

– What lies beneath the ice shell?

– What causes the formation of geysers on the surface?

– Is there any evidence of life, past or present?

– Is it likely that there will be life in the future? http://saturn.jpl.nasa.gov/photos/imagedetails/index.cfm?imageId=3748

Goals for the Darwin Mission

• Collect expelled material from geysers

• Develop lander• Develop method to drill and

sample ice• Measure and quantify seismic

activity of Enceladus• Take sample of atmosphere• Test electric connection between

Saturn and Enceladus• Drill at tiger stripes to breach ice

shell• Develop method to send samples

back to earth

http://saturn.jpl.nasa.gov/photos/imagedetails/index.cfm?imageId=3253

Power and Movement

• RTG power• Orbiter with

lander and detachable rover

• Antenna

http://en.wikipedia.org/wiki/Mars_Exploration_Rover

Dust Samples

• Cosmic Dust Analyzer

• Send dust samples back

http://onlinegeography.wikispaces.com/RE+-+Monitoring+and+Predicting+Volcanoes

Drilling

• Drill through ice at southern polar region

• Send ice samples back

http://michaeldemeng.blogspot.com/2011/03/art-lab-2-alchemist-toolbox-register.html

Seismic Activity and Craters

• Seismograph• Send rock

samples back• Panoramic

Cameras

http://lasp.colorado.edu/sdc/studyofdust.php#tab2

Atmosphere

• Magnetometer • Magnetosphere

Imaging Instrument

http://saturn.jpl.nasa.gov/news/newsreleases/newsrelease20010129/

Ethical Concerns

• Fuel leakage• Leaving rover

or other parts behind

http://www.thewatergeeks.com/Water-Contamination-sp-18.html

Cost

• Cassini-Huygens mission ~ $3.3 Billion

• Darwin Mission ~ $5 Billion

http://carlarpr.wordpress.com/2010/11/30/where-the-money-at/

Sources

Cassini , http://www.nasa.gov/mission_pages/cassini/spacecraft/index.html    Cassini FAQ , http://saturn.jpl.nasa.gov/faq/FAQMission/     Mars Rover , http://marsrovers.nasa.gov/overview/    

Status of Outer Planet Flagship Mission Studies,  http://www.lpi.usra.edu/pss/presentations/200707/niebur_flagship.pdf

Frictional heating explains plumes on Saturn's moon Enceladus, http://news.ucsc.edu/2007/05/1293.html

Cassini Solstice Mission, http://saturn.jpl.nasa.gov/spacecraft/cassiniorbiterinstruments/

NASA Cassini, http://www.nasa.gov/mission_pages/cassini/main/index.html

NASA Voyager, http://www.nasa.gov/mission_pages/voyager/index.html

NASA Pioneer, http://www.nasa.gov/mission_pages/pioneer/index.html

Cassini Observes the Active South Pole of Enceladus, http://www.sciencemag.org/content/311/5766/1393.full