…and more. I’m going to put our entire links/noted document on here. Star0bserver, David Hyde, and Billy Yelverton were instrumental in producing this research.
It’s a bit oif a data-dump, but it’s all relevant.
The Moons of Saturn
Titan:
NASA says: In many respects, Saturn’s largest moon, Titan, is one of the most Earth-like worlds we have found to date. With its thick atmosphere and organic-rich chemistry, Titan resembles a frozen version of Earth, several billion years ago, before life began pumping oxygen into our atmosphere.
Titan Moon Resources:
Cook, Jia-Rui; Brown, Dwayne. ‘Cassini Finds Likely Subsurface Ocean on Saturn Moon.’ NASA. Cassini: Unlocking Saturn’s Secrets. 28 June 2012. Website: http://www.nasa.gov/mission_pages/cassini/whycassini/cassini20120628.html
NASA. ‘Cassini Gets New Views of Titan’s Land of Lakes.’ Jet Propulsion Laboratory: Latest News. 23 October 2013. Website: http://www.jpl.nasa.gov/news/news.php?release=2013-304
NASA. ‘About Saturn & Its Moons.’ Jet Propulsion Laboratory: Cassini Solstice Mission. Website: http://saturn.jpl.nasa.gov/science/index.cfm?SciencePageID=73
Phillips, Dr. Tony. ‘Mystery of the Missing Waves on Titan.’ NASA Science News. 22 July 2013.
Website: http://science.nasa.gov/science-news/science-at-nasa/2013/22jul_titan/
Wikipedia: http://en.wikipedia.org/wiki/Titan_(moon)
Mimas:
The low density of Mimas, 1.15 g/cm³, indicates that it is composed mostly of water ice with only a small amount of rock. Mimas’s density and appearance suggest that it is a sphere of water ice with small pieces of rock mixed into the surface.
Mimas Moon Resources:
NASA. ‘About Saturn & Its Moons: Moons-Mimas.’ Cassini Solstice Mission. Website: http://saturn.jpl.nasa.gov/science/moons/mimas/
Wikipedia: http://en.wikipedia.org/wiki/Mimas_(moon)
Enceladus:
Enceladus seems to have liquid water under its icy surface. Cryovolcanoes at the south pole shoot large jets of water vapor, other volatiles and some solid particles (ice crystal, NaCl etc) into space (total approximately 200 kg per second). Some of this water falls back onto the moon as “snow”, some of it adds to Saturn’s rings, and some of it reaches Saturn. The whole of Saturn’s E Ring is believed to have been made from these ice particles. Because of the apparent water at or near the surface, Enceladus may be one of the best places for humans to look for extraterrestrial life.
In 2005 the Cassini spacecraft performed several close flybys of Enceladus, revealing the moon’s surface and environment in greater detail. In particular, the probe discovered a water-rich plume venting from the moon’s south polar region. This discovery, along with the presence of escaping internal heat and very few (if any) impact craters in the south polar region, shows that Enceladus is geologically active today. Moons in the extensive satellite systems of gas giants often become trapped in orbital resonances that lead to forced libration or orbital eccentricity; proximity to Saturn can then lead to tidal heating of Enceladus’s interior, offering a possible explanation for the activity.
Enceladus is one of only three outer Solar System bodies, with Jupiter’s moon Io’s sulfur volcanoes and Neptune’s moon Triton’s nitrogen “geysers” where active eruptions have been observed. Analysis of the outgassing suggests that it originates from a body of subsurface liquid water, which along with the unique chemistry found in the plume, has fueled speculations that Enceladus may be important in the study of astrobiology.[16] The discovery of the plume has added further weight to the argument that material released from Enceladus is the source of the E ring.
“New data from NASA’s Cassini proves that the intensity of the jets of water ice and organic particles that shoot out from Saturn’s moon Enceladus depends on its proximity to the ringed planet, offering further evidence that some kind of body of water is trapped beneath its surface…
“The way the jets react so responsively to changing stresses on Enceladus suggests they have their origins in a large body of liquid water,” said Christophe Sotin, a co-author and Cassini team member at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Liquid water was key to the development of life on Earth, so these discoveries whet the appetite to know whether life exists everywhere water is present…”
Enceladus Moon Resources:
Based on NASA/JPL report. ‘Atmosphere on Enceladus.’ Astrobiology Magazine. Posted 18 March 2005. Website: (Original NASA/JPL Report: http://saturn.jpl.nasa.gov/)
Article Source: http://www.astrobio.net/pressrelease/1490/atmosphere-on-enceladus
Black, Richard. ‘Saturn’s tiny moon Enceladus may be the best place to look for life elsewhere in the Solar System.’ BBC News. 10 April 2006. Website: http://news.bbc.co.uk/2/hi/science/nature/4895358.stm
Kemsley, Tamarra. ‘New Evidence Saturn’s Moon Enceladus Boasts Large Body of Water Uncovered.’ Nature World News. 02 August 2013. Website: http://www.natureworldnews.com/articles/3280/20130802/new-evidence-saturns-moon-enceladus-boasts-large-body-water-uncovered.htm
Lovett, Richard A. ‘Enceladus named sweetest spot for alien life.’ Nature, Published online 31 May 2011. doi:10.1038/news.2011.337 Website:
http://www.nature.com/news/2011/110531/full/news.2011.337.html
NASA. ‘Cassini Finds an Atmosphere on Saturn’s Moon Enceladus.’ Cassini Solstice Mission. 16 March 2005. Website: http://saturn.jpl.nasa.gov/news/newsreleases/newsrelease20050316/
NASA. ‘NASA’s Cassini Spacecraft Reveals Forces Controlling Saturn Moon Jets.’ Jet Propulsion Laboratory: Cassini Solstice Mission. 31 July 2013. Website:
http://saturn.jpl.nasa.gov/news/newsreleases/newsrelease20130731/
Spotts, Pete. ‘What’s going on inside Saturn Moon? Geysers offer intriguing new clue.’ Christian Science Monitor. 31 July 2013. Website:
http://www.csmonitor.com/Science/2013/0731/What-s-going-on-inside-Saturn-moon-Geysers-offer-intriguing-new-clue
The Telegraph. ‘Salt water caverns may be beneath surface of Saturn moon.’ 24 June 2009.
http://www.telegraph.co.uk/science/space/5625932/Salt-water-caverns-may-be-beneath-surface-of-Saturn-moon.html
Wikipedia: http://en.wikipedia.org/wiki/Enceladus
Tethys:
Tethys has a low density of 0.98 g/cm³ indicating that it is made up of water ice with just a small fraction of rock according to BBC. (NASA: Tethys’ density is 0.97 times that of liquid water, which suggests that Tethys is composed almost entirely of water ice plus a small amount of rock.) This is confirmed by the spectroscopy of its surface, which identified water ice as the dominant surface material.
The high albedo indicates that the surface of Tethys is composed of almost pure water ice with only a small amount of a dark material. No compound other than crystalline water ice has been unambiguously identified on Tethys. (Possible constituents include organics, ammonia and carbon dioxide.)
The extremely water-ice-rich composition of Tethys remains unexplained. The conditions in the Saturnian sub-nebula likely favored conversion of the molecular nitrogen and carbon monoxide into ammonia and methane, respectively. This can partially explain why Saturnian moons including Tethys contain more water ice than outer Solar System bodies like Pluto or Triton as the oxygen freed from carbon monoxide would react with the hydrogen forming water. One of the most interesting explanations proposed is that the rings and inner moons accreted from the tidally stripped ice-rich crust of a Titan-like moon before it was swallowed by Saturn.
Tethys Moon Resources:
BBC. ‘Tethys.’ Solar System: Moons. Website:http://www.bbc.co.uk/science/space/solarsystem/moons/tethys_(moon)
NASA. ‘Tethys: Overview.’ Solar System Exploration. National Aeronautics and Space Administration. Website: http://solarsystem.nasa.gov/planets/profile.cfm?Object=Tethys
Ostro, Steven J., West, Richard D, multiple authors. ‘Cassini RADAR observations of Enceladus, Tethys, Dione, Rhea, Iapetus, Hyperion, and Phoebe.’ Science Direct. 27 April 2006. Website: http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/40235/1/05-3668.pdf
Schenk, Paul; Hamilton, Doublas P; multiple authors. ‘Plasma, plumes and rings: Saturn system dynamics as recorded in global color patterns on its midsize icy satellites.’ The Smithsonian/NASA Astrophysics Data System. Icarus, Volume 211, Issue 1, p. 740-757. Website: http://adsabs.harvard.edu/abs/2011Icar..211..740S
Wikipedia: http://en.wikipedia.org/wiki/Tethys_(moon)
Dione:
It is composed primarily of water ice, but is the third densest of Saturn’s moons (after Enceladus and Titan, the density of which is increased by gravitational compression) it must have a considerable fraction (~ 46%) of denser material like silicate rock in its interior. suggesting stronger chances for internal heating
During a close pass of Cassini through the plasma wake of Saturn’s moon Dione on April 7, 2010 the Cassini Plasma Spectrometer (CAPS) detected molecular oxygen ions (O2+) on pickup ring velocity distributions, thus providing the first in situ detection of a neutral exosphere surrounding the icy moon.
The density of O2+ determined from the CAPS data ranges from 0.01 to 0.09 /cm3 and is used to estimate the exosphere O2 radial column density, obtaining the range 0.9 to 7 x 1011/cm2 . CAPS was unable to directly detect pick up H2O+ from the exosphere due to high background levels, but the observations can be used to set an upper limit to their density of ~10 times the O2+ density.
Dione Moon Resources:
‘Geophysical Research Letters.’ American Geophysical Union. ©2014 doi:10.1029/2011GL050452 Website: http://www.agu.org/pubs/crossref/pip/2011GL050452.shtml#content
Ghosh, Pallab. ‘Oxygen envelopes Saturn’s icy moon.’ BBC News: Science & Environment. 2 March 2012. Website: http://www.bbc.co.uk/news/science-environment-17225127
Lewis, Tanya. ‘Saturn’s Icy Moon Dione May Hide Watery Secret.’ Space.com 10 June 2013.
Website: http://www.space.com/21482-saturn-moon-dione-subsurface-ocean.html
NASA. ‘Cassina Finds Hints of Activity at Saturn Moon Dione.’ Jet Propulsion Laboratory: California Institute of Technology. 29 May 2013. Website:
http://www.jpl.nasa.gov/news/news.php?release=2013-178
Sven, Simon. ‘Magnetic Signatures of a Tenuous Atmosphere at Dione.’ Website:
http://onlinelibrary.wiley.com/doi/10.1029/2011GL048454/abstract
Wikipedia: http://en.wikipedia.org/wiki/Dione_(moon)
Rhea:
Rhea is an icy body with a density of about 1.236 g/cm3. This low density indicates that it is made of ~25% rock and ~75% water ice. Models suggest that Rhea could be capable of sustaining an internal liquid water ocean through heating by radioactive decay.
On November 27, 2010, NASA announced the discovery of a tenuous atmosphere—exosphere. It consists of oxygen and carbon dioxide in proportion of roughly 5 to 2. The main source of oxygen is radiolysis of water ice at the surface by ions supplied by the magnetosphere of Saturn.
Rhea Moon Resources:
Kerr, Richard A. ‘The Moon Rings That Never Were.’ Science Magazine: AAAS. 25 June 2010. Website: http://news.sciencemag.org/2010/06/moon-rings-never-were
NASA. ‘Moons-Rhea.’ About Saturn & Its Moons. Jet Propulsion Laboratory: California Institute of Technology. Website: http://saturn.jpl.nasa.gov/science/moons/rhea/
NASA. ‘Thin Air – Cassini Finds Ethereal Atmosphere at Rhea.’ Cassini: Unlocking Saturn’s Secrets. 26 November 2010. Website:
http://www.nasa.gov/mission_pages/cassini/whycassini/cassini20101126.html
Space.com ‘Saturn Moon Rhea’s Surprise: Oxygen-Rich Atmosphere.’ 25 November 2010. Website: http://www.space.com/9599-saturn-moon-rhea-surprise-oxygen-rich-atmosphere.html
Wikipedia: http://en.wikipedia.org/wiki/Rhea_(moon)
The Moons of Jupiter
Europa:
Europa’s bulk density suggests that it is similar in composition to the terrestrial planets, being primarily composed of silicate rock.
It is believed that Europa has an outer layer of water around 100 km (62 mi) thick; some as a frozen-ice upper crust and some as liquid ocean underneath the ice. Recent magnetic field data from the Galileo orbiter showed that Europa has an induced magnetic field through interaction with Jupiter’s, which suggests the presence of a subsurface conductive layer. The layer is likely a salty liquid water ocean. The crust is estimated to have undergone a shift of 80°, nearly flipping over, which would be unlikely if the ice were solidly attached to the mantle. Europa probably contains a metallic iron core.
Europa likely has eruptions of warm ice as the Europan crust spread open to expose warmer layers beneath. The effect would have been similar to that seen in Earth’s oceanic ridges.
In November 2011, a team of researchers from the University of Texas at Austin and elsewhere presented evidence in the journal Nature suggesting that many “chaos terrain” features on Europa sit atop vast lakes of liquid water. These lakes would be entirely encased in Europa’s icy outer shell and distinct from a liquid ocean thought to exist farther down beneath the ice shell. Europa has a layer of a highly electrically conductive material in Europa’s interior. The most plausible candidate for this role is a large subsurface ocean of liquid saltwater.
Europa may have periodically occurring plumes of water 200 km high, or more than 20 times the height of Mt. Everest. These plumes appear when Europa is at its farthest point from Jupiter, and are not seen when Europa is at its closest point to Jupiter, in agreement with tidal force modeling predictions.
Observations with the Goddard High Resolution Spectrograph revealed that Europa has a tenuous atmosphere composed mostly of molecular oxygen (O2). The surface pressure of Europa’s atmosphere is 0.1 μPa, or 10−12 times that of the Earth. In 1997, the Galileo spacecraft confirmed the presence of a tenuous ionosphere (an upper-atmospheric layer of charged particles) around Europa created by solar radiation and energetic particles from Jupiter’s magnetosphere, providing evidence of an atmosphere.
Unlike the oxygen in Earth’s atmosphere, Europa’s is not of biological origin. The surface-bounded atmosphere forms through radiolysis, the dissociation of molecules through radiation. Solar ultraviolet radiation and charged particles (ions and electrons) from the Jovian magnetospheric environment collide with Europa’s icy surface, splitting water into oxygen and hydrogen constituents. These chemical components are then adsorbed and “sputtered” into the atmosphere. The same radiation also creates collisional ejections of these products from the surface, and the balance of these two processes forms an atmosphere. Earth’s original oxygen was not organic either.
Europa has emerged as one of the top locations in the Solar System in terms of potential habitability and the possibility of hosting extraterrestrial life. Life could exist in its under-ice ocean, perhaps subsisting in an environment similar to Earth’s deep-ocean hydrothermal vents. Life in such an ocean could possibly be similar to microbial life on Earth in the deep ocean.
Europa Moon Resources:
‘Europa’s Crust and Ocean: Origin, Composition, and the Prospects for Life.’ Ideal Library: Icarus 148, 226-265 (2000). Website: http://www.planetary.brown.edu/pdfs/2440.pdf
‘Hubble discovers water vapour venting from Jupiter’s moon Europa.’ Hubble: Science Release. 12 December 2013. Website: http://www.spacetelescope.org/news/heic1322/
‘Hubble Finds Oxygen Atmosphere on Jupiter’s Moon, Europa.’ HubbleSite. News Release Number: STSci-1995-12. 23 February 1995. Website:
http://hubblesite.org/newscenter/archive/releases/1995/12/text/
Jackson School of Geosciences. ‘Scientists Find Evidence for ‘Great Lake’ on Europa and Potential New Habitat for Life.’ The University of Texas at Austin. 16 November 2011. Website:
http://www.jsg.utexas.edu/news/2011/11/scientists-find-evidence-for-great-lake-on-europa/
NASA. ‘Clay-Like Minerals Found on Icy Crust of Europa.’ Jet Propulsion Laboratory. 11 December 2013. Website: http://www.jpl.nasa.gov/news/news.php?release=2013-362
‘Possibility of Life on Europa.’ Website:
http://web.archive.org/web/20070217120400/http://people.msoe.edu/~tritt/sf/europa.life.html
Smyth, W. H. & Marconia, M. L. ‘Processes Shaping Galilean Satellite Atmospheres from the Surface to the Magnetosphere.’ Ices, Oceans, and Fire: Satellites of the Outer Solar System (2007). Website: http://www.lpi.usra.edu/meetings/icysat2007/pdf/6039.pdf
Wikipedia: http://en.wikipedia.org/wiki/Europa_(moon) 2nd Wikipedia:
http://en.wikipedia.org/wiki/Europa_Jupiter_System_Mission_%E2%80%93_Laplace
Io:
Io is primarily composed of silicate rock surrounding a molten iron or iron sulfide core. Most of Io’s surface is composed of extensive plains coated with sulfur and sulfur dioxide frost.
Scientists have found water molecules frozen in the surface ices of Jupiter’s moon Io. The absorption lines for water were found in the infrared spectrum of Io by scientists onboard NASA’s Kuiper Airborne Observatory (KAO).
Io is the only body in the solar system, except Earth, known to have intense volcanic activity. The Voyager spacecraft discovered active volcanoes on Io more than a decade ago.
Io Moon Resources:
‘Hubble discovers water vapour venting from Jupiter’s moon Europa.’ Hubble ESA: Science Release. 12 December 2013. Website: http://www.spacetelescope.org/news/heic1322/
Spencer, John R.; Lellouch, Emmanuel. ‘Mid-infrared detection of large longitudinal asymmetries in Io’s SO2 atmosphere.’ The Smithsonian/NASA Astrophysics Data System. Icarus, Volume 176, Issue 2, p. 283-304. Website: http://adsabs.harvard.edu/abs/2005Icar..176..283S
Strom, R. G.; Terrile, R. J.; Hansen, C.; Masursky, H. ‘Volcanic eruption plumes on Io.’ The Smithsonian/NASA Astrophysics Data System. Nature, vol. 280, p.733-736. 30 August 1979. Website: http://adsabs.harvard.edu/abs/1979Natur.280..733S
Wikipedia: http://en.wikipedia.org/wiki/Io_(moon)
Ganymede:
Ganymede is composed of approximately equal amounts of silicate rock and water ice. It is a fully differentiated body with an iron-rich, liquid core. A saltwater ocean is believed to exist nearly 200 km below Ganymede’s surface, sandwiched between layers of ice.
Water ice seems to be ubiquitous on the surface, with a mass fraction of 50–90%, significantly more than in Ganymede as a whole.The analysis of high-resolution, near-infrared and UV spectra obtained by the Galileo spacecraft and from the ground has revealed various non-water materials: carbon dioxide, sulfur dioxide and, possibly, cyanogen, hydrogen sulfate and various organic compounds.[5][35] Galileo results have also shown magnesium sulfate (MgSO4) and, possibly, sodium sulfate (Na2SO4) on Ganymede’s surface. These salts may originate from the subsurface ocean.
Evidence for a tenuous oxygen atmosphere (exosphere) on Ganymede, very similar to the one found on Europa, was found by the Hubble Space Telescope (HST) in 1995. HST actually observed airglow of atomic oxygen in the far-ultraviolet at the wavelengths 130.4 nm and 135.6 nm. Such an airglow is excited when molecular oxygen is dissociated by electron impacts, evidence of a significant neutral atmosphere composed predominantly of O2molecules.
Additional evidence of the oxygen atmosphere comes from spectral detection of gases trapped in the ice at the surface of Ganymede. The detection of ozone (O3) bands was announced in 1996. In 1997 spectroscopic analysis revealed the dimer (or diatomic) absorption features of molecular oxygen. Such an absorption can arise only if the oxygen is in a dense phase.
Ganymede Moon Resources:
Barr, Amy C.; Pappalardo, Robert T. ‘Rise of Deep Melt Into Ganymede’s Ocean and Implications for Astrobiology.’ Lunar and Planetary Science XXXII (2001). Website: http://www.lpi.usra.edu/meetings/lpsc2001/pdf/1781.pdf
Bland, M. T.; Showman, A.P. ‘Ganymede’s Orbital and Thermal Evolution and Its Effect on Magnetic Field Generation.’ Lunar and Planetary Science XXXVIII (2007). Website:
http://www.lpi.usra.edu/meetings/lpsc2007/pdf/2020.pdf
Carlson, R.W. ‘Atmosphere on Ganymede from Its Occultation of SAO 186800 on 7 June 1972.’ Science. 5 October 1973. Website: http://www.ncbi.nlm.nih.gov/pubmed/17829812
Hauck, II; Dombard, Andrew J. ‘Internal Structure and Mechanisms of Core Convection on Ganymede.’ Lunar and Planetary Science XXXIII (2002). Website:
http://www.lpi.usra.edu/meetings/lpsc2002/pdf/1380.pdf
‘Hydrated Salt Minerals on Ganymede’s Surface: Evidence of an Ocean Below.’ Science AAAS. 25 May 2001. Website: http://www.sciencemag.org/content/292/5521/1523
Volwerk, M. ‘Probing Ganymede’s magnetosphere with field line resonances.’ Journal of Geophysical Research Vol. 104 NO. A7. UCLA Institute of Geophysics & Planetary Physics. 1 July 1009. Website: http://www.igpp.ucla.edu/people/mkivelson/Publications/1999JA900161.pdf
Wikipedia: http://en.wikipedia.org/wiki/Ganymede_(moon)
Callisto:
Callisto’s exact amount of surface water ice is unknown, along with the existence of a liquid ocean, but it is likely the primary surface coverage material.
Callisto has a very tenuous atmosphere composed of carbon dioxide. Because such a thin atmosphere would be lost in only about 4 days (see atmospheric escape), it must be constantly replenished, possibly by slow sublimation of carbon dioxide ice from Callisto’s icy crust, which would be compatible with the sublimation–degradation hypothesis for the formation of the surface knobs.
Callisto’s high electron density cannot be explained by the photoionization of the atmospheric carbon dioxide alone. Hence, it is suspected that the atmosphere of Callisto is actually dominated by molecular oxygen (in amounts 10–100 times greater than CO2).
As with Europa and Ganymede, the idea has been raised that extraterrestrial microbial life may exist in a salty ocean under the Callistoan surface. However, the conditions for life appear to be less favorable on Callisto than on Europa. The principal reasons are the lack of contact with rocky material and the lower heat flux from the interior of Callisto.
Callisto Moon Resources:
Hibbitts, C.A. ‘Distributions of CO2 and SO2 on the Surface of Callisto.’ Lunar and Planetary Science XXXI (2000). Website: http://www.lpi.usra.edu/meetings/lpsc2000/pdf/1908.pdf
Khurana, K. K.; Kivelson, M.G. ‘Induced magnetic fields as evidence for subsurface oceans in Europa and Callisto.’ Letters to Nature Vol. 395 22 October 1998. Website:
http://www.igpp.ucla.edu/people/mkivelson/Publications/N395777.pdf
Klemaszekski, J.E. ‘Geological Evidence for an Ocean on Callisto.’ Lunar and Planetary Science XXXII (2001). Website: http://www.lpi.usra.edu/meetings/lpsc2001/pdf/1818.pdf
McGuire, Melissa L. ‘High Power MPD Nuclear Electric Propulsion (NEP) for Artificially Gravity HOPE Missions to Callisto.’ NASA/TM-2003-212349 (Technical Memo). Website:
http://trajectory.grc.nasa.gov/aboutus/papers/STAIF-2003-177.pdf
McKinnon, William B. ‘On convection in ice I shells of outer Solar System bodies, with detailed application to Callisto.’ The Smithsonian/NASA Astrophysics Data System. Icarus, Volume 183, Issue 2 p. 435-450 (2006). Website: http://adsabs.harvard.edu/abs/2006Icar..183..435M
Wikipedia: http://en.wikipedia.org/wiki/Callisto_(moon)
Pluto
In 2015, the Pluto system is due to be visited by spacecraft for the first time. The New Horizons probe will perform a flyby during which it will attempt to take detailed measurements and images of the plutoid and its moons.
Observations by the Hubble Space Telescope place Pluto’s density at between 1.8 and 2.1 g/cm3, suggesting its internal composition consists of roughly 50–70 percent rock and 30–50 percent ice by mass. Subsurface ocean possible.
Pluto’s atmosphere consists of a thin envelope of nitrogen, methane, and carbon monoxide gases.
Pluto has five known moons: Charon (the largest, with a diameter just over half that of Pluto), Nix, Hydra, Kerberos, and Styx. In 2007, observations by the Gemini Observatory of patches of ammonia hydrates and water crystals on the surface of Charon suggested the presence of active cryo-geysers.
Pluto Resources:
Lovett, Richard. A. ‘Pluto Has Oceans Under Ice?’ National Geographic: Daily News. 16 December 2010. Website: http://news.nationalgeographic.com/news/2010/12/101216-pluto-ocean-solar-system-science-space/
Redd, Nola Taylor. ‘NASA Probe to Search for Pluto’s Hidden Ocean.’ Space.com. 21, November 2011. Website: http://www.space.com/13703-pluto-horizons-subsurface-ocean.html
Wikipedia: http://en.wikipedia.org/wiki/Pluto
Mercury
David Paige and his colleagues provided the first detailed models of the surface and near-surface temperatures of Mercury’s north polar regions that utilize the actual topography of Mercury’s surface measured by the MLA. The measurements “show that the spatial distribution of regions of high radar backscatter is well matched by the predicted distribution of thermally stable water ice,” he writes.
The discovery of huge amounts of water ice and possible organic compounds on the heat-blasted planet Mercury suggests that the raw materials necessary for life as we know it may be common throughout the solar system, researchers say.
Mercury likely harbors between 100 billion and 1 trillion metric tons of water ice in permanently shadowed areas near its poles, scientists analyzing data from NASA’s Messenger spacecraft announced Thursday (Nov. 29).
Life on sun-scorched Mercury remains an extreme longshot, the researchers stressed, but the new results should still put a spring in the step of astrobiologists around the world.
Mercury Resources:
‘MESSENGER Finds New Evidence for Water Ice at Mercury’s Poles.’ MErcury Surface, Space ENvironment, GEochemistry, and Ranging. 29 November 2012 – Mission News. Website:
http://messenger.jhuapl.edu/news_room/details.php?id=233
NASA. ‘Messenger Finds New Evidence for Water at Mercury’s Poles.’ Messenger Mission to Mercury. 29 November 2012. Website:
http://www.nasa.gov/mission_pages/messenger/media/PressConf20121129.html#.Us8kTJ5dWJg
Tate, Karl. ‘Water Ice on Mercury: How It Stays Frozen (Infographic).’ Space.com. 29 November 2012. Website: http://www.space.com/18695-water-ice-mercury-explained-infographic.html
Wall, Mike. ‘Mercury’s Water Ice Bodes Well for Alien Life Search.’ Space.com. 30 November 2012. Website: http://www.space.com/18699-mercury-water-ice-alien-life.html
Starting Fire With Water
NASA-January 10, 2014:
Water becomes supercritical when it compressed to a pressure of 217 atmospheres and heated above 373 degrees C. Above that so-called critical point, ordinary H2O transforms into something that is neither solid, liquid, nor gas. It’s more of a “liquid-like gas.”
“When supercritical water is mixed with organic material, a chemical reaction takes place—oxidation.” Says Hicks. “It’s a form of burning without flames.”
Phillips, Dr. Tony. ‘Starting Fire With Water.’ NASA Science News – 10 January 2014. Website:
http://science.nasa.gov/science-news/science-at-nasa/2014/10jan_firewater/
‘Science Casts: Starting Fire in Water.’ NASA: ScienceAtNASA YouTube Channel. Published on 3 January 2014. Website: http://www.youtube.com/watch?v=TysrIYJOlpk
‘Unexpected Stable Stoichiometries of Sodium Chlorides’
Simple table salt, NaCl, is the only known stable phase of Na and Cl at ambient conditions. Previous attempts to understand its structure and chemical properties under pressure and at high temperatures revealed phase and bonding transitions, while keeping the balance of one Na to one Cl.
These experiments establish that compounds violating chemical intuition can be thermodynamically stable even in simple systems at nonambient conditions.
Resources:
‘Salty surprise: Ordinary table salt turns into ‘forbidden’ forms.’ PHYS.org – 19 December 2013. Website: http://phys.org/news/2013-12-salty-ordinary-table-salt-forbidden.html
Sci-News.com. ‘“Impossible” Sodium Chlorides Challenge Foundation of Chemistry.’ 20 December 2013. Website: http://www.sci-news.com/othersciences/chemistry/science-sodium-chlorides-foundation-chemistry-01633.html
Stony Brook Newsroom. ‘SBU Team Discovers New Compounds That Challenge the Foundation of Chemistry.’ Stony Brook University. 19 December 2013. Website: http://sb.cc.stonybrook.edu/news/general/Rocksalt.php
Zhang, Weiwei. ‘Unexpected Stabel Stoichiometries of Sodium Chlorides.’ Science AAAS: December 2013. Vol. 342 no. 6165 pp. 1502-1505. DOI: 10.1126/science.1244989. Website:
https://www.sciencemag.org/content/342/6165/1502.short
Article Source: http://sb.cc.stonybrook.edu/news/general/Rocksalt.php#sthash.Tl12OqJU.dpuf
If you apply the rather modest pressure of 200,000 atmospheres—for comparison purposes, the pressure at the center of the earth is 3.6 million atmospheres—everything we know from chemistry textbooks falls apart.
Standard chemistry textbooks say that sodium and chlorine have very different electronegativities, and thus must form an ionic compound with a well-defined composition. Sodium’s charge is +1, chlorine’s charge is -1; sodium will give away an electron, chlorine wants to take an electron. According to chemistry texts and common sense, the only possible combination of these atoms in a compound is 1:1—rock salt, or NaCl.
“These compounds are thermodynamically stable and, once made, remain indefinitely; nothing will make them fall apart. Classical chemistry forbids their very existence. Classical chemistry also says atoms try to fulfill the octet rule—elements gain or lose electrons to attain an electron configuration of the nearest noble gas, with complete outer electron shells that make them very stable. Well, here that rule is not satisfied.”
Habitable planets within the galaxy Outline
1. Do habitable planets exist around other stars? Yes.
b. How do we detect planets around other stars?
The only technique to have succeeded in finding Jovian-mass companions to main-sequence stars involves measuring periodic variations in the radial velocity of the target star as seen from Earth.
Lunine, Jonathan I. ‘In search of planets and life around other stars.’ Proceedings of the National Academy of Sciences of the USA. 11 May 1999. doi: 10.1073/pnas.96.10.5353. Website:
http://www.pnas.org/content/96/10/5353.full?sid=439ac1f5-f559-48b8-a95b-40fc71b9d04d
Petigura, Erik A. ‘Prevalence of Earth-size planets orbiting Sun-like Stars.’ PNAS – Journal of the American Chemical Society. doi: 10.1073/pnas.1319909110. 22 October 2013. Website:
http://www.pnas.org/content/110/48/19273.full?sid=439ac1f5-f559-48b8-a95b-40fc71b9d04d
c. How do we define a habitable zone?
Short Answer: A Habitable Zone (HZ) around a star is typically defined as the region where a rocky planet can maintain liquid water on its surface; this definition is NOT appropriate
Source:
Kasting, James F; Kipparapu, Ravikumar; Ramirez, Ramses M. ‘Remote life-detection criteria, habitable zone boundaries, and the frequency of Earth-like planets around M and late K stars.’ PNAS Astronomy – Special Feature. 31 October 2013. Website:
http://www.pnas.org/content/early/2013/11/20/1309107110.full.pdf+html?sid=439ac1f5-f559-48b8-a95b-40fc71b9d04d
a. How common are they?
Scientists from University of California, Berkeley, and University of Hawaii, Manoa, have statistically determined that twenty percent of Sun-like stars in our galaxy have Earth-sized planets that could host life. The findings, gleaned from data collected from NASA’s Kepler spacecraft and the W. M. Keck Observatory. One in Five Stars Has Earth-sized Planet in Habitable Zone.
Observatory in Waimea, Hawaii. ‘One in Five Stars has Earth-sized Planet in Habitable Zone.’ W.M. Keck Observatory. 4 November 2013. Website:
http://www.keckobservatory.org/recent/entry/one_in_five_stars_has_earth_sized_planet_in_habitable_zone
‘Prevalence of Earth-size planets orbiting Sun-like stars’
A major question is whether planets suitable for biochemistry are common or rare in the universe. Small rocky planets with liquid water enjoy key ingredients for biology. We used the National Aeronautics and Space Administration Kepler telescope to survey 42,000 Sun-like stars for periodic dimmings that occur when a planet crosses in front of its host star. We found 603 planets, 10 of which are Earth size and orbit in the habitable zone, where conditions permit surface liquid water. We measured the detectability of these planets by injecting synthetic planet-caused dimmings into Kepler brightness measurements. We find that 22% of Sun-like stars harbor Earth-size planets orbiting in their habitable zones.
Source:
Petigura, Erik A. ‘Prevalence of Earth-size planets orbiting Sun-like Stars.’ PNAS – Journal of the American Chemical Society. doi: 10.1073/pnas.1319909110. 22 October 2013. Website:
http://www.pnas.org/content/110/48/19273.full?sid=439ac1f5-f559-48b8-a95b-40fc71b9d04d
‘One in Five Stars Has Earth-sized Planet in Habitable Zone’
Scientists from University of California, Berkeley, and University of Hawaii, Manoa, have statistically determined that twenty percent of Sun-like stars in our galaxy have Earth-sized planets that could host life. The findings, gleaned from data collected from NASA’s Kepler spacecraft and the W. M. Keck Observatory, now satisfy Kepler’s primary mission: to determine how many of the 100 billion stars in our galaxy have potentially habitable planets.
…20 Billion Stars are candidates.
Source:
Observatory in Waimea, Hawaii. ‘One in Five Stars has Earth-sized Planet in Habitable Zone.’ W.M. Keck Observatory. 4 November 2013. Website:
http://www.keckobservatory.org/recent/entry/one_in_five_stars_has_earth_sized_planet_in_habitable_zone
‘At Least One in Six Stars Has an Earth-sized Planet’
Jan. 10, 2013 – The quest to determine if planets like Earth are rare or common is taking another stride forward on the journey. Using NASA’s Kepler spacecraft, managed by NASA Ames Research Center, astronomers are beginning to find Earth-sized planets orbiting distant stars. A new analysis of Kepler data shows that about 17 percent of stars have an Earth-sized planet in an orbit closer than Mercury. Since the Milky Way has about 100 billion stars, there are at least 17 billion Earth-sized worlds out there.
Source:
NASA. ‘At Least One in Six Stars Has an Earth-sized Planet.’ 10 January 2013. Website:
http://www.nasa.gov/mission_pages/kepler/news/17-percent-of-stars-have-earth-size-planets.html
‘Confirmed: A Star System with Three Potentially Habitable Planets!’
Late last year, Canadian astronomer Philip Gregory made the controversial claim that there are three habitable zone super-Earths orbiting the red dwarf star Gliese 667C. Now, in a separate study, a group of European astronomers are saying he was right.
Source:
‘Confirmed: A Star System with Three Potentially Habitable Planets!’ io9.com on 25 June 2013.
Website: http://io9.com/confirmed-a-star-system-with-three-potentially-habitab-571616316
‘Earth-like Planets Are Right Next Door’
Cambridge, MA – Using publicly available data from NASA’s Kepler space telescope, astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) have found that six percent of red dwarf stars have habitable, Earth-sized planets. Since red dwarfs are the most common stars in our galaxy, the closest Earth-like planet could be just 13 light-years away
Source:
‘Earth-like Planets Are Right Next Door.’ Harvard-Smithsonian Center for Astrophysics – Release No.: 2013-05. 6 February 2013. Website: http://www.cfa.harvard.edu/news/2013-05
‘2013 Jan 7. 2,740 Kepler Planet Candidates, a Family Portrait Poster’
Kepler Mission Planet Candidates:
Download High Res version (13 Mb pdf) or Print version (30 Mb pdf).
Originally this is the front of a poster prepared for Transit of Venus 2012 June 6 event
Using the prolific planet hunting Kepler spacecraft, astronomers have discovered 2,740 planet candidates orbiting other suns since the Kepler mission’s search for Earth-like worlds began in 2009.
Source:
NASA. ‘Kepler’s Planet Candidates: 2,740 as of January 2013.’ Ames Research Center. 07 January 2013 pdf. Credit: Mission/Kepler, Rowe/Chris, Burke/Wendy Stenzel. Website: http://kepler.nasa.gov/multimedia/artwork/diagrams/?ImageID=216
‘First Planet Found Around Solar Twin Star Cluster’
Published on January 15th, 2014 on ESO.org:
“Astronomers have used ESO’s HARPS planet hunter in Chile, along with other telescopes around the world, to discover three planets orbiting stars in the cluster Messier 67. Although more than one thousand planets outside the Solar System are now confirmed, only a handful have been found in star clusters. Remarkably one of these new exoplanets is orbiting a star that is a rare solar twin — a star that is almost identical to the Sun in all respects.”
The first of these planets proved to be orbiting a remarkable star — it is one of the most similar solar twins identified so far and is almost identical to the Sun (eso1337) [5]. It is the first solar twin in a cluster that has been found to have a planet.
Two of the three planets are “hot Jupiters” — planets comparable to Jupiter in size, but much closer to their parent stars and hence much hotter. All three are closer to their host stars than the habitable zone where liquid water could exist.
“These new results show that planets in open star clusters are about as common as they are around isolated stars — but they are not easy to detect,” adds Luca Pasquini (ESO, Garching, Germany), co-author of the new paper [6]. “The new results are in contrast to earlier work that failed to find cluster planets, but agrees with some other more recent observations. We are continuing to observe this cluster to find how stars with and without planets differ in mass and chemical makeup.”
Source:
ESO. ‘First Planet Found Around Solar Twin in Star Cluster.’ European Southern Observatory. ESO – Science Release, 15 January 2014. Website: http://www.eso.org/public/news/eso1402/
LAST MINUTE ADDITIONS
http://www.hawaii.edu/news/article.php?aId=6249
http://www.pnas.org/content/early/2014/01/16/1320115111.abstract
http://www2.ess.ucla.edu/~jewitt/papers/2006/HJ06.pdf
http://arxiv.org/abs/1312.0673