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Circumstellar habitable zone
In astronomy and astrobiology, the circumstellar habitable zone (CHZ), or simply the habitable zone, is the range of orbits around a star within which a planetary surface can support liquid water given sufficient atmospheric pressure.[1][2] The bounds of the CHZ are based on Earth's position in the Solar System and the amount of radiant energy it receives from the Sun. Due to the importance of liquid water to Earth's biosphere, the nature of the CHZ and the objects within it may be instrumental in determining the scope and distribution of Earth-like extraterrestrial life and intelligence.
The habitable zone is also called the Goldilocks zone, a metaphor of the children's fairy tale of "Goldilocks and the Three Bears", in which a little girl chooses from sets of three items, ignoring the ones that are too extreme (large or small, hot or cold, etc.), and settling on the one in the middle, which is "just right".
Since the concept was first presented in 1953,[3] many stars have been confirmed to possess a CHZ planet, including some systems that consist of multiple CHZ planets.[4] Most such planets, being super-Earths or gas giants, are more massive than Earth, because such planets are easier to detect. On November 4, 2013, astronomers reported, based on Kepler data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of Sun-like stars and red dwarfs in the Milky Way.[5][6] 11 billion of these may be orbiting Sun-like stars.[7] Proxima Centauri b, located about 4.2 light-years (1.3 parsecs) from Earth in the constellation of Centaurus, is the nearest known exoplanet, and is orbiting in the habitable zone of its star.[8] The CHZ is also of particular interest to the emerging field of habitability of natural satellites, because planetary-mass moons in the CHZ might outnumber planets.[9]
In subsequent decades, the CHZ concept began to be challenged as a primary criterion for life, so the concept is still evolving.[10] Since the discovery of evidence for extraterrestrial liquid water, substantial quantities of it are now thought to occur outside the circumstellar habitable zone. The concept of deep biospheres, like Earth's, that exist independently of stellar energy, are now generally accepted in astrobiology given the large amount of liquid water known to exist within in lithospheres and asthenospheres of the Solar System.[11] Sustained by other energy sources, such as tidal heating[12][13] or radioactive decay[14] or pressurized by non-atmospheric means, liquid water may be found even on rogue planets, or their moons.[15] Liquid water can also exist at a wider range of temperatures and pressures as a solution, for example with sodium chlorides in seawater on Earth, chlorides and sulphates on equatorial Mars,[16] or ammoniates,[17] due to its different colligative properties. In addition, other circumstellar zones, where non-water solvents favorable to hypothetical life based on alternative biochemistries could exist in liquid form at the surface, have been proposed.[18]
The concept of a circumstellar habitable zone was first introduced in 1953 by Hubertus Strughold, who in his treatise The Green and the Red Planet: A Physiological Study of the Possibility of Life on Mars coined the term "ecosphere" and referred to various "zones" in which life could emerge.[3][19] In the same year, Harlow Shapley wrote "Liquid Water Belt", which described the same theory in further scientific detail. Both works stressed the importance of liquid water to life.[20] Su-Shu Huang, an American astrophysicist, first introduced the term "habitable zone" in 1959 to refer to the area around a star where liquid water could exist on a sufficiently large body, and was the first to introduce it in the context of planetary habitability and extraterrestrial life.[21][22] A major early contributor to habitable zone theory, Huang argued in 1960 that circumstellar habitable zones, and by extension extraterrestrial life, would be uncommon in multiple star systems, given the gravitational instabilities of those systems.[23]
The theory of habitable zones was further developed in 1964 by Stephen H. Dole in his book Habitable Planets for Man, in which he covered the circumstellar habitable zone itself as well as various other determinants of planetary habitability, eventually estimating the number of habitable planets in the Milky Way to be about 600 million.[24] At the same time, science-fiction author Isaac Asimov introduced the concept of a circumstellar habitable zone to the general public through his various explorations of space colonization.[25] The term "Goldilocks zone" emerged in the 1970s, referencing specifically a region around a star whose temperature is "just right" for water to be present in the liquid phase.[26] In 1993, astronomer James Kasting introduced the term "circumstellar habitable zone" to refer more precisely to the region then (and still) known as the habitable zone.[21]
An update to habitable-zone theory came in 2000, when astronomers Peter Ward and Donald Brownlee introduced the idea of the "galactic habitable zone", which they later developed with Guillermo Gonzalez.[27][28] The galactic habitable zone, defined as the region where life is most likely to emerge in a galaxy, encompasses those regions close enough to a galactic center that stars there are enriched with heavier elements, but not so close that star systems, planetary orbits, and the emergence of life would be frequently disrupted by the intense radiation and enormous gravitational forces commonly found at galactic centers.[27]
Subsequently, some astrobiologists propose that the concept be extended to other solvents, including dihydrogen, sulfuric acid, dinitrogen, formamide, and methane, among others, which would support hypothetical life forms that use an alternative biochemistry.[18] In 2013, further developments in habitable zone theory were made with the proposal of a circumplanetary habitable zone, also known as the "habitable edge", to encompass the region around a planet where the orbits of natural satellites would not be disrupted, and at the same time tidal heating from the planet would not cause liquid water to boil away.[29]
Whether a body is in the circumstellar habitable zone of its host star is dependent on the radius of the planet's orbit (for natural satellites, the host planet's orbit), the mass of the body itself, and the radiative flux of the host star. Given the large spread in the masses of planets within a circumstellar habitable zone, coupled with the discovery of super-Earth planets which can sustain thicker atmospheres and stronger magnetic fields than Earth, circumstellar habitable zones are now split into two separate regions—a "conservative habitable zone" in which lower-mass planets like Earth or Venus can remain habitable, complemented by a larger "extended habitable zone" in which super-Earth planets, with stronger greenhouse effects, can have the right temperature for liquid water to exist at the surface.[31]
The inner edge of the HZ is the distance where a runaway greenhouse effect vaporizes the whole water reservoir and,[10] as a second effect, induces the photodissociation of water vapor and the loss of hydrogen to space. The outer edge of the HZ is the distance from the star where adding more carbon dioxide to the atmosphere fails to keep the surface of the planet above the freezing point.[10]
Solar System estimates[edit]
Estimates for the habitable zone within the Solar System range from 0.5 to 3.0 astronomical units,[32] though arriving at these estimates has been challenging for a variety of reasons. Numerous planetary mass objects orbit within, or close to, this range and as such receive sufficient sunlight to raise temperatures above the freezing point of water. However their atmospheric conditions vary substantially. The aphelion of Venus, for example, touches the inner edge of the zone and while atmospheric pressure at the surface is sufficient for liquid water, a strong greenhouse effect raises surface temperatures to 462 °C (864 °F) at which water can only exist as vapour.[33] The entire orbits of the Moon,[34] Mars,[35] and numerous asteroids also lie within various estimates of the habitable zone. Only at Mars' lowest elevations (less than 30% of the planet's surface) is atmospheric pressure and temperature sufficient for water to, if present, exist in liquid form for short periods.[36] At Hellas Basin, for example, atmospheric pressures can reach 1,115 Pa and temperatures above zero Celsius (around the triple point for water) for 70 days in the Martian year.[36] Despite indirect evidence in the form of seasonal flows on warm Martian slopes,[37][38][39][40] no confirmation has been made of the presence of liquid water there. While other objects orbit partly within this zone, including comets, Ceres[41] is the only one of planetary mass. A combination of low mass and an inability to mitigate evaporation and atmosphere loss against the solar wind make it impossible for these bodies to sustain liquid water on their surface. Most estimates, therefore, are inferred from the effect that a repositioned orbit would have on the habitability of Earth or Venus.
According to extended habitable zone theory, planetary mass objects with atmospheres capable of inducing sufficient radiative forcing could possess liquid water farther out from the Sun. Such objects could include those whose atmospheres contain a high component of greenhouse gas and terrestrial planets much more massive than Earth (super-Earth class planets), that have retained atmospheres with surface pressures of up to 100 kbar. There are no examples of such objects in the Solar System to study; not enough is known about the nature of atmospheres of these kinds of extrasolar objects, and the net temperature effect of such atmospheres including induced albedo, anti-greenhouse or other possible heat sources cannot be determined by their position in the habitable zone.
Inner edge (AU) | Outer edge (AU) | Year | Notes |
0.725 | 1.24 | Dole 1964[24] | Used optically thin atmospheres and fixed albedos. Places the aphelion of Venus just inside the zone. |
1.385–1.398 | Budyko 1969[42] | Based on studies of ice albedo feedback models to determine the point at which Earth would experience global glaciation. This estimate was supported in studies by Sellers 1969[43] and North 1975.[44] | |
0.88–0.912 | Rasool and De Bergh 1970[45] | Based on studies of Venus's atmosphere, Rasool and De Bergh concluded that this is the minimum distance at which Earth would have formed stable oceans. | |
0.95 | 1.01 | Hart et al. 1979[46] | Based on computer modelling and simulations of the evolution of Earth's atmospheric composition and surface temperature. This estimate has often been cited by subsequent publications. |
3.0 | Fogg 1992[30] | Used the carbon cycle to estimate the outer edge of the circumstellar habitable zone. | |
1.37 | Kasting et al. 1993[21] | Noted the cooling effect of cloud albedo. | |
2.0 | Spiegel et al. 2010[47] | Proposed that seasonal liquid water is possible to this limit when combining high obliquity and orbital eccentricity. | |
0.75 | Abe et al. 2011[48] | Found that land-dominated "desert planets" with water at the poles could exist closer to the Sun than watery planets like Earth. | |
0.77—0.87 | 1.02—1.18 | Vladilo et al. 2013[49] | Inner edge of circumstellar habitable zone is closer and outer edge is farther for higher atmospheric pressures; determined minimum atmospheric pressure required to be 15 millibar. |
0.99 | 1.688 | Kopparapu et al. 2013[1] | Revised estimates using updated runaway greenhouse and water loss algorithms. According to this measure Earth is at the inner edge of the HZ and close to, but just outside, the runaway greenhouse limit. This applies to a planet with Earth-like atmospheric composition and pressure. |
0.5 | Zsom et al. 2013 [50] |
Estimate based on various possible combinations of atmospheric composition, pressure and relative humidity of the planet's atmosphere. |
Extrasolar extrapolation[edit]
Astronomers use stellar flux and the inverse-square law to extrapolate circumstellar habitable zone models created for the Solar System to other stars. For example, although the Solar System has a circumstellar habitable zone centered at 1.34 AU from the Sun,[1] a star with 0.25 times the luminosity of the Sun would have a habitable zone centered at , or 0.5, the distance from the star, corresponding to a distance of 0.67 AU. Various complicating factors, though, including the individual characteristics of stars themselves, mean that extrasolar extrapolation of the CHZ concept is more complex.
Spectral types and star-system characteristics[edit]
Some scientists argue that the concept of a circumstellar habitable zone is actually limited to stars in certain types of systems or of certain spectral types. Binary systems, for example, have circumstellar habitable zones that differ from those of single-star planetary systems, in addition to the orbital stability concerns inherent with a three-body configuration.[51] If the Solar System were such a binary system, the outer limits of the resulting circumstellar habitable zone could extend as far as 2.4 AU.[52][53]
With regard to spectral types, Zoltán Balog proposes that O-type stars cannot form planets due to the photoevaporation caused by their strong ultraviolet emissions.[54] Studying ultraviolet emissions, Andrea Buccino found that only 40% of stars studied (including the Sun) had overlapping liquid water and ultraviolet habitable zones.[55] Stars smaller than the Sun, on the other hand, have distinct impediments to habitability. For example, Michael Hart proposed that only main-sequence stars of spectral class K0 or brighter could offer habitable zones, an idea which has evolved in modern times into the concept of a tidal locking radius for red dwarfs. Within this radius, which is coincidental with the red-dwarf habitable zone, it has been suggested that the volcanism caused by tidal heating could cause a "tidal Venus" planet with high temperatures and no hospitable environment to life.[56]
Others maintain that circumstellar habitable zones are more common and that it is indeed possible for water to exist on planets orbiting cooler stars. Climate modelling from 2013 supports the idea that red dwarf stars can support planets with relatively constant temperatures over their surfaces in spite of tidal locking.[57] Astronomy professor Eric Agol argues that even white dwarfs may support a relatively brief habitable zone through planetary migration.[58] At the same time, others have written in similar support of semi-stable, temporary habitable zones around brown dwarfs.[56]
Stellar evolution[edit]
Circumstellar habitable zones change over time with stellar evolution. For example, hot O-type stars, which may remain on the main sequence for fewer than 10 million years,[59] would have rapidly changing habitable zones not conducive to the development of life. Red dwarf stars, on the other hand, which can live for hundreds of billions of years on the main sequence, would have planets with ample time for life to develop and evolve.[60][61] Even while stars are on the main sequence, though, their energy output steadily increases, pushing their habitable zones farther out; our Sun, for example, was 75% as bright in the Archaean as it is now,[62] and in the future, continued increases in energy output will put Earth outside the Sun's habitable zone, even before it reaches the red giant phase.[63] In order to deal with this increase in luminosity, the concept of a continuously habitable zone has been introduced. As the name suggests, the continuously habitable zone is a region around a star in which planetary-mass bodies can sustain liquid water for a given period of time. Like the general circumstellar habitable zone, the continuously habitable zone of a star is divided into a conservative and extended region.[63]
In red dwarf systems, gigantic stellar flares which could double a star's brightness in minutes[64] and huge starspots which can cover 20% of the star's surface area,[65] have the potential to strip an otherwise habitable planet of its atmosphere and water.[66] As with more massive stars, though, stellar evolution changes their nature and energy flux,[67] so by about 1.2 billion years of age, red dwarfs generally become sufficiently constant to allow for the development of life.[66][68]
Once a star has evolved sufficiently to become a red giant, its circumstellar habitable zone will change dramatically from its main-sequence size.[69] For example, the Sun is expected to engulf the previously-habitable Earth as a red giant.[70] However, once a red giant star reaches the horizontal branch, it achieves a new equilibrium and can sustain a new circumstellar habitable zone, which in the case of the Sun would range from 7 to 22 AU.[71] At such stage, Saturn's moon Titan would likely be habitable in Earth's temperature sense.[72] Given that this new equilibrium lasts for about 1 Gyr, and because life on Earth emerged by 0.7 Gyr from the formation of the Solar System at latest, life could conceivably develop on planetary mass objects in the habitable zone of red giants.[71] However, around such a helium-burning star, important life processes like photosynthesis could only happen around planets where the atmosphere has been artificially seeded with carbon dioxide, as by the time a solar-mass star becomes a red giant, planetary-mass bodies would have already absorbed much of their free carbon dioxide.[73]
Desert planets[edit]
A planet's atmospheric conditions influence its ability to retain heat, so that the location of the habitable zone is also specific to each type of planet: desert planets (also known as dry planets), with very little water, will have less water vapor in the atmosphere than Earth and so have a reduced greenhouse effect, meaning that a desert planet could maintain oases of water closer to its star than Earth is to the Sun. The lack of water also means there is less ice to reflect heat into space, so the outer edge of desert-planet habitable zones is further out.[74][75]
Other considerations[edit]
A planet cannot have a hydrosphere—a key ingredient for the formation of carbon-based life—unless there is a source for water within its stellar system. The origin of water on Earth is still not completely understood; possible sources include the result of impacts with icy bodies, outgassing, mineralization, leakage from hydrous minerals from the lithosphere, and photolysis.[76][77] For an extrasolar system, an icy body from beyond the frost line could migrate into the habitable zone of its star, creating an ocean planet with seas hundreds of kilometers deep[78] such as GJ 1214 b[79][80] or Kepler-22b may be.[81]
Maintenance of liquid surface water also requires a sufficiently thick atmosphere. Possible origins of terrestrial atmospheres are currently theorised to outgassing, impact degassing and ingassing.[82] Atmospheres are thought to be maintained through similar processes along with biogeochemical cycles and the mitigation of atmospheric escape.[83] In a 2013 study led by Italian astronomer Giovanni Vladilo, it was shown that the size of the circumstellar habitable zone increased with greater atmospheric pressure.[49] Below an atmospheric pressure of about 15 millibars, it was found that habitability could not be maintained[49] because even a small shift in pressure or temperature could render water unable to form as a liquid.[84]
In the case of planets orbiting in the CHZs of red dwarf stars, the extremely close distances to the stars cause tidal locking, an important factor in habitability. For a tidally locked planet, the sidereal day is as long as the orbital period, causing one side to permanently face the host star and the other side to face away. In the past, such tidal locking was thought to cause extreme heat on the star-facing side and bitter cold on the opposite side, making many red dwarf planets uninhabitable; however, three-dimensional climate models in 2013, showed that the side of a red dwarf planet facing the host star could have extensive cloud cover, increasing its bond albedo and reducing significantly temperature differences between the two sides.[57]
Planetary-mass natural satellites have the potential to be habitable as well. However, these bodies need to fulfill additional parameters, in particular being located within the circumplanetary habitable zones of their host planets.[29] More specifically, moons need to be far enough from their host giant planets that they are not transformed by tidal heating into volcanic worlds like Io,[29] but must still remain within the Hill radius of the planet so that they are not pulled out of orbit of their host planet.[85] Red dwarfs that have masses less than 20% of that of the Sun cannot have habitable moons around giant planets, as the small size of the circumstellar habitable zone would put a habitable moon so close to the star that it would be stripped from its host planet. In such a system, a moon close enough to its host planet to maintain its orbit would have tidal heating so intense as to eliminate any prospects of habitability.[29]
A planetary object that orbits a star with high orbital eccentricity may spend only some of its year in the CHZ and experience a large variation in temperature and atmospheric pressure. This would result in dramatic seasonal phase shifts where liquid water may exist only intermittently. It is possible that subsurface habitats could be insulated from such changes and that extremophiles on or near the surface might survive through adaptions such as hibernation (cryptobiosis) and/or hyperthermostability. Tardigrades, for example, can survive in a dehydrated state temperatures between 0.150 K (−273 °C)[86] and 424 K (151 °C).[87] Life on a planetary object orbiting outside CHZ might hibernate on the cold side as the planet approaches the apastron where the planet is coolest and become active on approach to the periastron when the planet is sufficiently warm.[88]
Extrasolar discoveries[edit]
Among exoplanets, a review in 2015 came to the conclusion that Kepler-62f, Kepler-186f and Kepler-442b were likely the best candidates for being potentially habitable.[89] These are at a distance of 1200, 490 and 1,120 light-years away, respectively. Of these, Kepler-186f is similar in size to Earth with a 1.2-Earth-radius measure, and it is located towards the outer edge of the habitable zone around its red dwarf star. Among nearest terrestrial exoplanet candidates, Tau Ceti e is 11.9 light-years away. It is in the inner edge of its solar system's habitable zone, giving it an estimated average surface temperature of 68 °C (154 °F).[90]
Studies that have attempted to estimate the number of terrestrial planets within the circumstellar habitable zone tend to reflect the availability of scientific data. A 2013 study by Ravi Kumar Kopparapu put ηe, the fraction of stars with planets in the CHZ, at 0.48,[1] meaning that there may be roughly 95–180 billion habitable planets in the Milky Way.[91] However, this is merely a statistical prediction; only a small fraction of these possible planets have yet been discovered.[92]
Previous studies have been more conservative. In 2011, Seth Borenstein concluded that there are roughly 500 million habitable planets in the Milky Way.[93] NASA's Jet Propulsion Laboratory 2011 study, based on observations from the Kepler mission, raised the number somewhat, estimating that about "1.4 to 2.7 percent" of all stars of spectral class F, G, and K are expected to have planets in their CHZs.[94][95]
Early findings[edit]
The first discoveries of extrasolar planets in the CHZ occurred just a few years after the first extrasolar planets were discovered. One of the first discoveries was 70 Virginis b, a gas giant initially nicknamed "Goldilocks" due to it being neither "too hot" nor "too cold." Later study revealed temperatures analogous to Venus, ruling out any potential for liquid water.[96] 16 Cygni Bb, also discovered in 1996, has an extremely eccentric orbit that causes extreme seasonal effects on the planet's surface. In spite of this, simulations have suggested that it is possible for a terrestrial natural satellite to support water at its surface year-round.[97]
Gliese 876 b, discovered in 1998, and Gliese 876 c, discovered in 2001, are both gas giants discovered in the habitable zone around Gliese 876. Although they are not thought to possess significant water at their surfaces, both may have habitable moons.[98] Upsilon Andromedae d, discovered in 1999, is a gas giant in its star's circumstellar habitable zone considered to be large enough to favor the formation of large, Earth-like moons.[99]
Announced on April 4, 2001, HD 28185 b is a gas giant found to orbit entirely within its star's circumstellar habitable zone[100] and has a low orbital eccentricity, comparable to that of Mars in the Solar System.[101] Tidal interactions suggest that HD 28185 b could harbor habitable Earth-mass satellites in orbit around it for many billions of years,[102] though it is unclear whether such satellites could form in the first place.[103]
HD 69830 d, a gas giant with 17 times the mass of Earth, was found in 2006 orbiting within the circumstellar habitable zone of HD 69830, 41 light years away from Earth.[104] The following year, 55 Cancri f was discovered within the CHZ of its host star 55 Cancri A.[105][106] Although conditions on this massive and dense planet are not conducive to the formation of water or life as we know it, a hypothetical moon of this planet with the proper mass and composition could be able to support liquid water at its surface.[107]
Habitable super-Earths[edit]
The 2007 discovery of Gliese 581 c, the first super-Earth in the circumstellar habitable zone, created significant interest in the system by the scientific community, although the planet was later found to have extreme surface conditions that may resemble Venus.[108] Gliese 581 d, another planet in the same system and thought to be a better candidate for habitability, was also announced in 2007. Its existence was later disconfirmed in 2014. Gliese 581 g, yet another planet thought to have been discovered in the circumstellar habitable zone of the system, was considered to be more habitable than both Gliese 581 c and d. However, its existence was also disconfirmed in 2014.[109]
Discovered in August 2011, HD 85512 b was initially speculated to be habitable,[110] but the new circumstellar-habitable-zone criteria devised by Kopparapu et al. in 2013 place the planet outside the circumstellar habitable zone.[92] With an increase in the frequency of exoplanet discovery, the Earth Similarity Index was devised in October 2011 as a way of comparing planetary properties, such as surface temperature and density, to those of Earth in order to better gauge the habitability of extrasolar bodies.[111]
Kepler-22 b, discovered in December 2011 by the Kepler space probe,[112] is the first transiting exoplanet discovered around a Sun-like star. With a radius 2.4 times that of Earth, Kepler-22b has been predicted by some to be an ocean planet.[113] Gliese 667 Cc, discovered in 2011 but announced in 2012,[114] is a super-Earth orbiting in the circumstellar habitable zone of Gliese 667 C. Subsequently in June 2013, two other habitable super-Earths orbiting the same star, Gliese 667 Cf and Gliese 667 Ce, were discovered in the CHZ.[115]
Gliese 163 c, discovered in September 2012 in orbit around the red dwarf Gliese 163[116] is located 49 light years from Earth. The planet has 6.9 Earth masses and 1.8–2.4 Earth radii, and with its close orbit receives 40 percent more stellar radiation than Earth, leading to surface temperatures of about 60° C.[117][118][119] HD 40307 g, a candidate planet tentatively discovered in November 2012, is in the circumstellar habitable zone of HD 40307.[120] In December 2012, Tau Ceti e and Tau Ceti f were found in the circumstellar habitable zone of Tau Ceti, a Sun-like star 12 light years away.[121] Although more massive than Earth, they are among the least massive planets found to date orbiting in the habitable zone;[122] however, Tau Ceti f, like HD 85512 b, did not fit the new circumstellar habitable zone criteria established by the 2013 Kopparapu study.[123]
Earth-sized planets and Solar analogs[edit]
Recent discoveries have uncovered planets that are thought to be similar in size or mass to Earth. While there is no universal definition of "Earth-sized", ranges are typically defined by mass. The lower range used in many definitions of the super-Earth class is 1.9 Earth masses, likewise, sub-Earths range up to the size of Venus (~0.815 Earth masses). An upper limit of 1.5 Earth radii is also considered, given that above 1.5 R⊕ the average planet density rapidly decreases with increasing radius, indicating that these planets have a large fraction of volatiles by volume overlying a rocky core.[124] Solar analogs and solar twins are stars that resemble the Sun. To date no solar twin with an exact match as that of the Sun has been found, however, there are some stars that are nearly identical to the Sun, and are such considered solar twins. An exact solar twin would be a G2V star with a 5,778 K temperature, be 4.6 billion years old, with the correct metallicity and a 0.1% solar luminosity variation.[125] Stars with an age of 4.6 billion years are at the most stable state. Proper metallicity and size are also very important to low luminosity variation.[126][127][128]
On 7 January 2013, astronomers from the Kepler team announced the discovery of Kepler-69c (formerly KOI-172.02), an Earth-size exoplanet candidate (1.7 times the radius of Earth) orbiting Kepler-69, a star similar to our Sun, in the CHZ and expected to offer habitable conditions.[129][130][131][132] The discovery of two planets orbiting in the habitable zone of Kepler-62, by the Kepler team was announced on April 19, 2013. The planets, named Kepler-62e and Kepler-62f, are likely solid planets with sizes 1.6 and 1.4 times the radius of Earth, respectively.[131][132][133]
With a radius estimated at 1.1 Earth, Kepler-186f, discovery announced in April 2014, is the closest yet size to Earth of an exoplanet confirmed by the transit method[134][135][136] though its mass remains unknown and its parent star is not a Solar analog.
On 6 January 2015, NASA announced the 1000th confirmed exoplanet discovered by the Kepler Space Telescope. Three of the newly confirmed exoplanets were found to orbit within habitable zones of their related stars: two of the three, Kepler-438b and Kepler-442b, are near-Earth-size and likely rocky; the third, Kepler-440b, is a super-Earth.[137] Announced 16 January, EPIC 201367065 d is a planet of 1.5 Earth radii found to orbit within the habitable zone of EPIC 201367065, receiving 1.4 times the intensity of visible light as Earth.[138]
Kepler-452b, announced on 23 July 2015 is 50% bigger than Earth, likely rocky and takes approximately 385 Earth days to orbit the habitable zone of its G-class (solar analog) star Kepler-452.[139][140]
The discovery of a system of three tidally-locked planets orbiting the habitable zone of an ultracool dwarf star, TRAPPIST-1, was announced in May 2016.[141] The discovery is considered significant because it greatly increases the possibility of smaller, cooler, more numerous and closer stars possessing habitable planets.
Notable exoplanets – Kepler Space Telescope |
(Kepler-62e, Kepler-62f, Kepler-186f, Kepler-296e, Kepler-296f, Kepler-438b, Kepler-440b, Kepler-442b) (Kepler Space Telescope; January 6, 2015).[137] |
Habitability outside the CHZ[edit]
Liquid-water environments have been found to exist in the absence of atmospheric pressure, and at temperatures outside the CHZ temperature range. For example, Saturn's moons Titan and Enceladus and Jupiter's moons Europa and Ganymede, all of which are outside the habitable zone, may hold large volumes of liquid water in subsurface oceans.[142]
Outside the CHZ, tidal heating and radioactive decay are two possible heat sources that could contribute to the existence of liquid water.[12][13] Abbot and Switzer (2011) put forward the possibility that subsurface water could exist on rogue planets as a result of radioactive decay-based heating and insulation by a thick surface layer of ice.[15]
With some theorising that life on Earth may have actually originated in stable, subsurface habitats,[143][144] it has been suggested that it may be common for wet subsurface extraterrestrial habitats such as these to 'teem with life'.[145] Indeed, on Earth itself living organisms may be found more than 6 kilometres below the surface.[146]
Another possibility is that outside the CHZ organisms may use alternative biochemistries that do not require water at all. Astrobiologist Christopher McKay, has suggested that methane (CH
4) may be a solvent conducive to the development of "cryolife", with the Sun's "methane habitable zone" being centered on 1,610,000,000 km (1.0×109 mi; 11 AU) from the star.[18] This distance is coincidental with the location of Titan, whose lakes and rain of methane make it an ideal location to find McKay's proposed cryolife.[18] In addition, testing of a number of organisms has found some are capable of surviving in extra-CHZ conditions.[147]
Significance for complex and intelligent life[edit]
The Rare Earth hypothesis argues that complex and intelligent life is uncommon and that the CHZ is one of many critical factors. According to Ward & Brownlee (2004) and others, not only is a CHZ orbit and surface water a primary requirement to sustain life but a requirement to support the secondary conditions required for multicellular life to emerge and evolve. The secondary habitability factors are both geological (the role of surface water in sustaining necessary plate tectonics)[27] and biochemical (the role of radiant energy in supporting photosynthesis for necessary atmospheric oxygenation).[148] But others, such as Ian Stewart and Jack Cohen in their 2002 book Evolving the Alien argue that complex intelligent life may arise outside the CHZ.[149] Intelligent life outside the CHZ may have evolved in subsurface environments, from alternative biochemistries[149] or even from nuclear reactions.[150]
On Earth, several complex multicellular life forms (or eukaryotes) have been identified with the potential to survive conditions that might exist outside the conservative habitable zone. Geothermal energy sustains ancient circumvental ecosystems, supporting large complex life forms such as Riftia pachyptila.[151] Similar environments may be found in oceans pressurised beneath solid crusts, such as those of Europa and Enceladus, outside of the habitable zone.[152] Numerous microorganisms have been tested in simulated conditions and in low Earth orbit, including eukaryotes. An animal example is the Milnesium tardigradum, which can withstand extreme temperatures well above the boiling point of water and the cold vacuum of outer space.[153] In addition, the plants Rhizocarpon geographicum and Xanthoria elegans have been found to survive in an environment where the atmospheric pressure is far too low for surface liquid water and where the radiant energy is also much lower than that which most plants require to photosynthesize.[154][155][156] The fungi Cryomyces antarcticus and Cryomyces minteri are also able to survive and reproduce in Mars-like conditions.[156]
Species, including humans, known to possess animal cognition require large amounts of energy,[157] and have adapted to specific conditions, including an abundance of atmospheric oxygen and the availability of large quantities of chemical energy synthesized from radiant energy. If humans are to colonize other planets, true Earth analogs in the CHZ are most likely to provide the closest natural habitat; this concept was the basis of Stephen H. Dole's 1964 study. With suitable temperature, gravity, atmospheric pressure and the presence of water, the necessity of spacesuits or space habitat analogues on the surface may be eliminated and complex Earth life can thrive.[24]
Planets in the CHZ remain of paramount interest to researchers looking for intelligent life elsewhere in the universe.[158] The Drake equation, sometimes used to estimate the number of intelligent civilizations in our galaxy, contains the factor or parameter ne, which is the average number of planetary-mass objects orbiting within the CHZ of each star. A low value lends support to the Rare Earth hypothesis, which posits that intelligent life is a rarity in the Universe, whereas a high value provides evidence for the Copernican mediocrity principle, the view that habitability—and therefore life—is common throughout the Universe.[27] A 1971 NASA report by Drake and Bernard Oliver proposed the "waterhole", based on the spectral absorption lines of the hydrogen and hydroxyl components of water, as a good, obvious band for communication with extraterrestrial intelligence[159][160] that has since been widely adopted by astronomers involved in the search for extraterrestrial intelligence. According to Jill Tarter, Margaret Turnbull and many others, CHZ candidates are the priority targets to narrow waterhole searches[161][162] and the Allen Telescope Array now extends Project Phoenix to such candidates.[163]
Because the CHZ is considered the most likely habitat for intelligent life, METI efforts have also been focused on systems likely to have planets there. The 2001 Teen Age Message and the 2003 Cosmic Call 2, for example, were sent to the 47 Ursae Majoris system, known to contain three Jupiter-mass planets and possibly with a terrestrial planet in the CHZ.[164][165][166][167] The Teen Age Message was also directed to the 55 Cancri system, which has a gas giant in its CHZ.[105] A Message from Earth in 2008,[168] and Hello From Earth in 2009, were directed to the Gliese 581 system, containing three planets in the CHZ—Gliese 581 c, d, and the unconfirmed g.
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- ^ "Kepler 22-b: Earth-like planet confirmed". BBC. December 5, 2011. Retrieved May 2, 2013.
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- ^ Anglada-Escude, Guillem; Arriagada, Pamela; Vogt, Steven; Rivera, Eugenio J.; Butler, R. Paul; Crane, Jeffrey D.; Shectman, Stephen A.; Thompson, Ian B.; Minniti, Dante (2012). "A planetary system around the nearby M dwarf GJ 667C with at least one super-Earth in its habitable zone". arXiv:1202.0446 [astro-ph.EP].
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- ^ Moore, Matthew (October 9, 2008). "Messages from Earth sent to distant planet by Bebo". London: .telegraph.co.uk. Archived from the original on 11 October 2008. Retrieved 2008-10-09.
External links[edit]
Look up habitable zone in Wiktionary, the free dictionary. |
Wikimedia Commons has media related to Habitable zone. |
- "Circumstellar Habitable Zone Simulator". Astronomy Education at the University of Nebraska-Lincoln.
- "The Habitable Exoplanets Catalog". PHL/University of Puerto Rico at Arecibo.
- "The Habitable Zone Gallery".
- "Stars and Habitable Planets". SolStation.
- Nikos Prantzos (2006). "On the Galactic Habitable Zone". Space Science Reviews. 135: 313–322. arXiv:astro-ph/0612316. Bibcode:2008SSRv..135..313P. doi:10.1007/s11214-007-9236-9.
- Interstellar Real Estate: Location, Location, Location – Defining the Habitable Zone
- "Exoplanets in relation to host star's current habitable zone". www.planetarybiology.com.
- "exoExplorer: a free Windows application for visualizing exoplanet environments in 3D". www.planetarybiology.com.
- Shiga, David (November 19, 2009). "Why the universe may be teeming with aliens". NewScientist.
- Simmons; et al. "The New Worlds Observer: a mission for high-resolution spectroscopy of extra-solar terrestrial planets" (PDF). New Worlds.
- Cockell, Charles S.; Herbst, Tom; Léger, Alain; Absil, O.; Beichman, Charles; Benz, Willy; Brack, Andre; Chazelas, Bruno; Chelli, Alain (2009). "Darwin – an experimental astronomy mission to search for extrasolar planets" (PDF). Experimental Astronomy. 23: 435–461. Bibcode:2009ExA....23..435C. doi:10.1007/s10686-008-9121-x.
- Atkinson, Nancy (March 19, 2009). "JWST Will Provide Capability to Search for Biomarkers on Earth-like Worlds". Universe Today.


text:
breasts,had done 15 yrs. ago had 325cc, the doctor put in 375cc but my nipples are not in the middle any more they are at the bottlem of my breasts and they are hard and high at the top,they hurt and some times feels like blood is running down on the inside and it burns,i had it done dec.27,2011 should it be looking right by now?i went back to the doctor and he said i was so swolling at first that its going take longer for them to set in the pocket and gave me a bar strap,did not help...........
2nd Time Breast Implants One Went Down Have 325cc,now 375cc Down Pointing Nipples and Hard at Top?
Doctor Answers 1
You are right and something is not right with your implant replacement. Could you have hematomas or bleeding, poorly shaped implant pockets? It is hard to say though your breast should be soft and the implants well centered on the nipple. You might need another opinion.
Web reference: http://www.peterejohnsonmd.com
These answers are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.

subset: commoncrawl


text:
PRAGUE, Czech Republic, October 6, 2011 – AVAST Software has launched avast! EasyPass, the password manager designed to make life simpler and more secure.
Modern technology requires passwords for bank accounts, programs, websites and more. While using a single password is a security risk, storing passwords on scraps of paper is an organizational nightmare. That's why there is avast! EasyPass, the password manager that puts security at the user's fingertips.
"EasyPass is a rare phenomenon: an application that saves people time and headaches while also increasing their level of security," said Vince Steckler, CEO of AVAST Software. "As people add more computers to their households, they are also increasing the number of passwords – and their need for a way to quickly and easily remember them."
Out of over 67,000 new avast! users recently surveyed, only 11.5% said they had a password manager installed on their computers. But, survey participants had three specific wishes for what this application – if they had it – should do:
"avast! users recognize that re-entering the same data into their computers is a waste of time. While these avast! users ranked speed above security and memory assistance, the survey results showed they want a password manager which does more than a sticky note on their computer," commented Mr. Steckler.
EasyPass has been designed to meet these avast! users' expectations for a password saver:
"Computer users want convenience, they expect security. Now with avast! EasyPass, they can have both," said Mr. Steckler. avast! EasyPass is available only through the AVAST online shop. For more information, go to http://www.avast.com/lp-easypass-password-manager.
Protect all of your devices with the world's leading cyber security software.


text:
Samsung widget offers pseudo Start menu in Windows 8 We don't always like it when system vendors layer their own user interface elements on top of the operating system. The supposed enhancements are often... Type: News story Tags: Software Operating systems |
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Leaked Valleyview slides detail next-gen Atom SoC Some possible details have leaked out regarding next-generation Atom processors. The information comes from an official-looking presentation deck published by EXPreview. Most of the... Type: News story Tags: CPUs Graphics Chipsets |
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Jury finds Samsung violated Apple patents The jury in Apple's patent infringement case against Samsung has found that Samsung violated a great many of the patents Apple sought to enforce, and... Poll Question: • Your reaction to the Apple-Samsung verdict? Type: News story Tags: Operating systems Personal tech |
568 |
Zotac updates Zbox Nano with Brazos 2.0 We loved the Zotac Zbox Nano AD10 when we reviewed it last year. Into a chassis small enough to fit in the palm of... Type: News story Tags: CPUs Graphics Chipsets Systems |
45 |
Win8 to include personal license for DIY system builders Microsoft has added a new user license for Windows 8. Dubbed the Personal Use License for System Builders, this license is designed for folks who... Type: News story Tags: Operating systems |
40 |
Rumor: Microsoft may hasten Windows release cycle We all remember the long dry spell between the releases of Windows XP and Vista—and Steve Ballmer's subsequent promise that it would never happen... Type: News story Tags: Operating systems Windows |
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Report: Windows 8 won't support booting to the desktop Microsoft may be retiring Metro as a brand name, but the Metro interface will still be front and center in Windows 8—more so than you... Type: News story Tags: Operating systems Windows |
157 |
Windows 8 RTM allegedly leaked already On Wednesday, Microsoft released Windows 8 to manufacturing. Now, barely two days later, we're hearing that the same Windows 8 build has already leaked... Type: News story Tags: Operating systems Windows |
31 |
Windows 8 hits RTM, on track for release Whether you like the changes in the next version of Microsoft's operating system or not, Windows 8 is on track for its October 26 launch.... Type: News story Tags: Operating systems |
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Windows 8 offers improved graphics performance In a little more than three months, Windows 8 will be released to the public. Microsoft has done a great job of detailing... Type: News story Tags: Graphics Operating systems |
125 |
Asus, HTC commit to Android 4.1 updates Android 4.1 Jelly Bean is out, but the number of devices running Google's latest OS is relatively small. Only a handful of the company's... Type: News story Tags: Mobile computing Operating systems Personal tech |
57 |
Report: Haswell chipsets add 6Gbps SATA, USB 3.0 ports Intel typically releases fresh platform hubs, otherwise known as chipsets, with new CPUs. According to DigiTimes, Haswell and its accompanying 8-series platform hubs are... Type: News story Tags: Motherboards Chipsets |
28 |
Windows 8's release set for October 26 Over the past few weeks, we've seen Microsoft progressively narrow its release time frame for Windows 8. First it was this fall, and then it... Type: News story Tags: Operating systems Windows |
61 |
Microsoft confirms October release for Windows 8 Well, it's official: Windows 8 will become commercially available in late October. Microsoft spilled the beans at its Worldwide Partner Conference in Toronto this morning,... Type: News story Tags: Operating systems Windows |
106 |
Only 11% of Android devices run Ice Cream Sandwich Android 4.0, otherwise known as Ice Cream Sandwich, was released last fall. More than eight months later, it's migrated to just 11% of Android... Type: News story Tags: Mobile computing Operating systems Personal tech |
98 |
Microsoft to offer cheap Windows 8 upgrades to everyone You get a cheap Windows 8 upgrade! And you get a cheap Windows 8 upgrade! Everyone gets a cheap Windows 8 upgrade! Yes, it seems, Microsoft... Type: News story Tags: Operating systems Windows |
167 |
Restrictions on Windows 8 in-place upgrades detailed Windows 8's retail release is fast approaching. Unless the new Metro user interface gives you a rash, you might be thinking of upgrading—and an in-place... Type: News story Tags: Operating systems Windows |
38 |
Leaked slides tease Haswell-EP details Although server-grade CPUs based on Intel's Ivy Bridge silicon have yet to arrive, rumors are already swirling about what's in the cards for Intel's next,... Type: News story Tags: CPUs Chipsets Servers Workstations |
25 |
Asus GTX 1080 and 1060 cards with faster RAM go the extra mile | 10 |


text:
Mums Coconut Cream Pie Aka Birthday Pie Recipe
Here's yet another Thanksgiving pie in our family. Coconut cream was my mom's favorite pie. Her birthday sometimes fell on Thanksgiving - whether or...
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Coconut Cream Pie I
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milk, +flaked coconut
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Quick Coconut Cream Pie
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milk, +flaked coconut
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Coconut Custard Pie (Tammy's Blend Pie)
A family recipe I've made for years for dozens of people. Only one hasnt liked it sofar. Coconut floats to the top and crisps, while pie makes its own...
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Coconut Cream Pie IV
"Creamy and delicious coconut flavored pie. A serious contender for the 'Best Pie in the Universe' title."
milk, +butter, +cornstarch, +egg whites, +egg yolks, +flaked coconut, +salt, +vanilla extract, +sugar
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Coconut Cream Pie Recipe
I love this coconut cream pie with whipping cream on top, as my grandma use to make this all the time. Prep:15m
milk, +flaked coconut, +cornstarch, +splenda, +egg yolks, +butter, +coconut extract, +salt, +vanilla extract
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text:
Fans of the World and European champion may not be able to watch their side in action on Friday after Spanish broadcasters failed to agree a deal over TV rights.
As things stand no Spanish television companies are planning to show the Group I encounter from Minsk after failing to agree a deal with the host broadcasters.
They have approximately 48 hours to try and broker a deal or the match will not be shown around the country.
German company Sportfive owns the rights to the game and is holding out for a fee of 1.5 million euros after originally requesting 3 million euros, but Spain's delicate economic situation has left broadcasters concerned that they cannot afford to show the clash.
Spanish newspaper AS has spoken to a number of potential buyers in the country and the belief is that at the current price it would not be profitable to show the match.
This is not the first time this season that there have been issues regarding television rights in Spain, after a similar dispute unfolded before La Roja's win over Georgia in September, though a deal was eventually agreed.
Follow GOAL.COM USA on


text:
- Member: Kanti13
- Title: Mello/Near Tribute
- Premiered: 2008-02-08
- Categories:
- Evanescence Lacrymosa
- Anime:
This is a tribute to Mello AND Near. Not a Mello X Near tribute. It is in no way intended to be yaoi. I'm not saying that there's something wrong with yaoi, so if you would enjoy it more to interpret it that way than whatever. I just personally can't stand them as a couple. I like Mello x Matt, but that's beside the point.
This is the first video I did with Magix.
Spoilers from ep 35.
Opinions (0)
- Link Format Bitrate Codec Duration Filesize Link Check Information Comments
- Links for this video are no longer available.


text:
Vauxhall Partners
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What is Vauxhall Partners?
Vauxhall Partners is our exclusive benefits programme, giving you and your family great offers on:.
- New Vauxhall discounts – great savings across our range.
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text:
- Item 21 of 33 in Collection: Long Trail Photographs
- | Return to collection
Item Description
Title: Northern Pileated Woodpecker
- Brounell, L.W.
Source Document
Extent: 1 lantern slide : hand col. ; 3.25 x 4 in.
Date Created: Undated
Image created by L.W. Brounell of Paterson N.J.
Genre(s): photographs, lantern slides
Note [Digital Version]
2009-09-05, Center for Digital Initiatives, University of Vermont Libraries
Note [Original Notation]
Northern Pil. Woodpecker. Northern Pileated Woodpeckers Fuentes. Made by L.W. Brounell of Paterson N.J. -fr. Fuentes
Type of Resource: still image
Parent Collections
Access Conditions
For usage rights related to this resource please visit: http://cdi.uvm.edu/rights/
More information.
Permanent Link:
Preferred citation
Northern Pileated Woodpecker, Theron S. Dean Papers, Box 4, http://cdi.uvm.edu/collections/item/deanb03074 (accessed March 26, 2017)


text:
SAN QUENTIN, Calif. (AP) — State prisons officials say an inmate has died at San Quentin State Prison after a four-story fall at the facility.
The Marin County coroner says that 60-year-old convicted murderer Thomas Curby Henderson died Tuesday after being taken to the hospital following a fall from the fourth tier of his prison unit.
The coroner said Henderson's fall appeared to be a suicide.
Henderson was serving a 40-years-to-life term in prison, and was set to have his first parole hearing March 12.
Henderson was imprisoned after first-and-second-degree murder convictions in 1985 for the killing of his ex-girlfriend and her 5-year-old son in San Diego County.
Terry Thornton, a spokeswoman for the California Department of Corrections and Rehabilitation, says the prison is also investigating the death.
(Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)


text:
PC Games
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by Michelle Badash, MS
Menkes syndrome is an inherited genetic disorder due to an abnormal gene, ATP7A. Menkes syndrome causes impaired copper absorption. This results in changes in the arteries and deterioration of the brain.
Menkes syndrome is rare. Most children born with Menkes syndrome have a life expectancy of 3-5 years of age.
Copper proteins are necessary for the body to build bone, nerves, and other tissue. Babies with Menkes syndrome have a genetic disorder that prevents the absorption of copper from the intestines and causes it to build up in excess amounts in the kidney, while remaining deficient in the liver and brain. This causes changes in the hair, brain, bones, liver, and arteries.
Menkes syndrome is more common in males, and in those with a family history.
Children with Menkes are often born prematurely. Symptoms usually begin within 3 months after birth and may include:
Copyright © Nucleus Medical Media, Inc.
Babies with Menkes syndrome often exhibit the following physical characteristics:
The following tests may be done to diagnose Menkes syndrome:
There is no cure for Menkes syndrome. Early treatment with IV copper acetate, oral copper supplements, or injections of copper histidinate may provide temporary benefit. Other treatments may be used to relieve symptoms.
There is no known way to prevent Menkes syndrome. If you have a family history of the disorder, you can talk to a genetic counselor when deciding whether to have children.
National Institute of Neurological Disorders and Stroke
ORDR—Office of Rare Diseases Research
About Kids Health—The Hospital for Sick Children
CORD—Canadian Organization for Rare Disorders
Kaler SG. ATP7A-Related Copper Transport Disorders. GeneReviews website. Available at: http://www.ncbi.nlm.nih.gov/books/NBK1413. Updated October 14, 2010. Accessed August 6, 2015.
Menkes syndrome. Genetics Home Reference website. Available at: https://ghr.nlm.nih.gov/condition/menkes-syndrome. Updated March 2009. Accessed August 6, 2015.
NINDS Menkes disease information page. National Institute of Neurological Disorders and Stroke website. Available at: http://www.ninds.nih.gov/disorders/menkes/menkes.htm. Updated September 30, 2011. Accessed August 6, 2015.
Last reviewed September 2016 by Michael Woods, MD, FAAP
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
Copyright © EBSCO Publishing. All rights reserved.


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What's Happened In The Trayvon Martin Case Since You Stopped Paying Attention
Written by Judd Legum
It's been nearly a year since George Zimmerman shot and killed Trayvon Martin, an unarmed 17-year-old on his way back to his father's townhouse. In the weeks following the shooting, the story captured the nation's attention, culminating with Zimmerman being charged with second-degree murder last April.
But as the story has receded from the headlines, the legal case has plodded along and the trial is likely to be completed this summer. Here's what you may have missed:
1. Zimmerman has spent over $300,000 in donations over the last year and is desperate for more funds to finance his defense. Zimmerman has "spent more than $125,000″ on living expenses — not including security — over the last year. His lawyer acknowledged that "Zimmerman's personal spending may seem exorbitant." Zimmerman is considering asking the court to declare him "indigent, meaning the public would have to pay for Zimmerman's defense." Zimmerman was also sued by a security company for unpaid bills. [Orlando Sentinel, 1/20/2013; Miami Herald, 12/27/12]
2. The trial has been set for June 10. Zimmerman recently asked for a delay of the trial until November but a judge denied his request. Zimmerman's lawyer says it is "physically impossible for us to be prepared" for trial at that time. A separate proceeding, essentially a mini-trial, to determine whether Zimmerman is immune from prosecution due to Florida's "Stand Your Ground" law, is scheduled for April 22. [Orlando Sentinel, 2/5/13; Headline News, 2/13/13]
3. New forensic analysis "casts doubt on Zimmerman's timeline on the night he shot and killed the unarmed teen." The analysis was done by "Michael Knox, a retired Jacksonville Sheriff's Office detective and crime scene investigator." According to Knox, "based on the times and distances Zimmerman said he covered, Zimmerman would have still been on the phone with Sanford police when he claims he was attacked by Martin." Knox says that other aspects of Zimmerman's story, like the claim Martin was leaning over him at the time the shot was fired, are supported by forensic evidence. [News 4 Jacksonville, 2/10/13]
4. Zimmerman has gained 105 pounds. [Orlando Sentinel, 1/20/2013]
5. The defense team acquired Trayvon Martin's school records. According to Zimmerman's lawyers "some information in Trayvon Martin's file could be relevant in the defense of George Zimmerman." State prosecutors and the Martin family attorney opposed Zimmerman's efforts to acquire the records arguing "because Zimmerman did not know Trayvon before the Feb. 26 shooting, the teen's past was not a factor in the case." [Orlando Sentinel, 1/16/13]
6. Zimmerman is suing NBC News. In the suit, Zimmerman claims NBC unfairly portrayed him as a "racist and predatory villain." [ABC News, 12/6/12]
7. The judged denied Zimmerman's request to be removed from GPS tracking. [Fox Orlando, 12/11/12]
8. Trayvon Martin would have turned 18 on February 5. [Huffington Post, 2/5/13]
This post was originally published by ThinkProgress.
Photo: JanvanSchijndel/flickr


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Hi I'm new in this forum. My wii simply doesn't turn on anymore. I have seen other threads however none of them applies to my case... Since about a year ago, my wii wouldn't read many discs, so, since there is no FREE nintendo hardware support where I live in Mexico, I decided to open it up and clean up the reader. I had to do that several times until TODAY. I opened it up and since cleaning the reader no longer worked, I figured increasing the potentiometer would work. It actually worked more or less fine, so I decided to open it up again to increase it just a bit further. BUT after increasing just tiny bit of the potentionmeter I decided to turn on the wii to check how good was it. However I accidentally presed the led instead of the power botton with my screwdriver and suddenly a little bit of smoke rose up and from there after it would no longer turn on. (Note that the wii front cover was off) I don't know what to do, I'm panicked. I've had that wii since launch and it has ALL my save games. I wouldn't mind that much buying a new wii if i could only rescue my saves. Does anybody hay any idea on what to do?
Hiya, its me. I COULD help ya out a bit. What you could possibly do is buy a new Wii and have a memory transplant (more or less like a kidney or liver transplant) but what i highly advise next time you get a wii, INSTALL BOOTMII ;D
Well, you fried your Wii. There's nothing really anyone can do now. They're not made to be user-servicable. There's a reason the Wii uses security screws... it's a way of Nintendo telling you: "Don't open this up, there's nothing you can do and you'll probably do damage". Which you did. Those potentiometers are meant to be calibrated at the factory by a trained technician using special tools. Not people messing around with a screwdriver because the figured out how to open the Wii. I understand there's no free support in Mexico but you should've opted for some sort of paid professional support, because as you'll see now that would've been cheaper than a new Wii (and having to start all-over on all your games).


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TESSCO Earns TL 9000 Certification and Maintains ISO 9001:2008 |
HUNT VALLEY, Md.--(BUSINESS WIRE)--May. 22, 2012-- TESSCO Technologies Incorporated (NASDAQ:TESS), a leading provider of the product and value chain solutions required to build, use and maintain wireless systems, today announced that it has achieved TL 9000 certification (TL14163) - a demanding, international Quality Management System (QMS) built on ISO 9001 principles. TL 9000, an extension of ISO: 9001, is designed to validate a QMS governing the design, development, production, delivery, installation, and maintenance of products and services for telecommunications. Created and continually improved by The Quality Excellence for Suppliers of To achieve this distinction, aspects of TESSCO's business were audited by In addition to the new TL 9000, Registration No: TL14163 About TESSCO Technologies (NASDAQ:TESS), is Your Total Source® for making wireless work. The convergence of wireless and the Internet is revolutionizing the way we live and work. New systems and applications are unlocking human potential at an unprecedented rate. Source: TESSCO Technologies Incorporated |


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The Shortlist for March 13
Police are interested in questioning Russell Brand after a photographer filed a report claiming Brand grabbed the paparazzo's iPhone and threw it through the window of an abandoned building. The scuffle allegedly went down in New Orleans Monday night, when Timothy Jackson spotted Brand on the street and tried to photograph him, according to TMZ. Brand, who's currently in the Big Easy filming Diablo Cody's untitled new project, landed in hot water in 2010 when he lashed out at a pap who tried to take a picture angled up Katy Perry's skirt. (GossipCop)


text: Working Moms Still Getting The ShaftMegan Carpentier6/08/09 6:20pmFiled to: Mind the gapMarried wage gapWage equalitywage gapworking momsGettypic57EditPromoteShare to KinjaToggle Conversation toolsGo to permalinkConservatives who like to blame the wage gap on women's choices should know: working mothers are 100% less likely to be hired than childless candidates, and get offered $11,000 less a year when they are. Some "choices." [Business Week]Reply57 repliesLeave a reply


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This section contains 2,762 words (approx. 7 pages at 400 words per page) |
Taking the deer hunt from William Faulkner's story "The Old People" as a model of the literary tradition of a hunt as a boy's initiation into manhood, Loftis shows how the conventions are subverted in Dave's killing of the mule.
For a people living in a new and unsettled land, variations on the archetype of the young hero who achieves manhood by hunting and slaying a wild beast came early and naturally as a literary theme. American writers have consistently dramatized the threat of the wilderness as an element in their heroes' rites du passage. The courageous and determined Natty Bumpo, the Deerslayer, is still an All- American hero and a model for the heroes of later generations. Captain Ahab, equally courageous in his madness, is perhaps the archetype in its demonic or perverted form. Modern writers continue the tradition: Hemingway with Francis Macomber and Faulkner with...
This section contains 2,762 words (approx. 7 pages at 400 words per page) |