Life+on+Other+Planets+-+JS

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Rubric: [[file:Space Exploration Adventure Rubric.doc]], [[file:Space Exploration Adventure Rubric.pdf]]

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There may be as many as 50,000 planets that have conditions suitable for life. These conditions are called the Goldilocks conditions because the temperature can not be too hot or too cold, it has to be just right. The requirements for life on Earth are liquid water, a suitable temperature range, and an atmosphere for living things to survive. Scientist aren't sure whether these conditions are necessary for all life or just life on Earth because Earth is the only example of life to look at.

The three most likely candidates for extraterrestrial life are Mars, Europa, and Kepler22b.

Out of all 3, Mars is the most likely to contain life. One reason why scientists think there could be life on Mars is that it might have liquid water on it's surface. using telescopes, astronomers have noticed areas in the terrain that look like canals. Also, Mars, the fourth planet from the sun, is inside the habitable zone. The habitable is a theoretical band a certain distance from the sun that would be optimal for life.

Europa is the fourth largest of Jupiter's moons. It's interesting to astronomers because it has strong tidal heat that could keep the inside of Europa warm enough to have liquid water beneath it's surface. Europa has an icy surface with low ridges crisscrossing the surface it's surface. The surface is smooth with barely any craters on it, unlike Callisto and Ganymede, two of Jupiter's other moons.

Kepler 22b is a planet located 600 light-years away. It was just discovered in 2010. Kepler 22b has a 290 day revolution around it's star, much like Earth's revolution around the sun. It is 2.4 times the radius of Earth but it's mass and surface composition are unknown. Like Mars, Kepler is in the habitable zone and it has the cabibility to hold liquid water. these characteristics have earned the planet the nickname "Earth's twin".

Recently, organisms have been found living in extreme conditions on Earth, in places previosly thought unable to sustain life. One example of this is hydrothermal vents. Hydrothermal vents are found living an average of 2,100 feet below the ocean. This shows that life can form where conditions are not optimal.

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Visuals Make sure to include the location of your image; add a caption with this information
 * [[image:http://static.ddmcdn.com/gif/alien-physiology-tubeworm2a.jpg caption="UFO images"]] ||  || [[image:http://1-ps.googleusercontent.com/h/www.universetoday.com/wp-content/uploads/2009/05/249x249xnasa_mars-249x249.jpg.pagespeed.ic.AHViwo8lEs.jpg width="249" height="249" caption="Mars. Credit: NASA"]] ||
 * || [[image:http://earthguide.ucsd.edu/virtualmuseum/images/EuropaSurface.jpg caption="external image EuropaSurface.jpg" link="javascript/popup3"]] || [[image:http://upload.wikimedia.org/wikipedia/commons/thumb/1/1e/Kepler22b-artwork.jpg/300px-Kepler22b-artwork.jpg width="300" height="225" caption="Kepler22b-artwork.jpg" link="http://en.wikipedia.org/wiki/File:Kepler22b-artwork.jpg"]] ||
 * || [[image:http://earthguide.ucsd.edu/virtualmuseum/images/Europa.jpg caption="external image Europa.jpg" link="javascript/popup"]] || [[image:http://earthguide.ucsd.edu/virtualmuseum/images/GalileanMoonsofJupiter.jpg caption="external image GalileanMoonsofJupiter.jpg" link="javascript/popup2"]] ||
 * || media type="youtube" key="VGG7kagzouM" height="315" width="560" ||  ||

**Works Cited** **Sources** : Include the source information for all of the magazine articles, reference sources (encyclopedias) and web site pages that were used to complete your project. The source information for encyclopedias may be found at the end or beginning of each entry in iCONN. When using periodicals, the publication information will be at the beginning or end of the article. This needs to be formatted for MLA standards. If it is not labeled 'Source Citation' it can be formatted appropriately by using EasyBib.com. You should use EasyBib for the web sites. The final Works Cited should be listed in alphabetical order by the first word of the source citation. "Milky Way." //Kids InfoBits Presents: Astronomy//. Gale, 2008. Reproduced in Kids InfoBits. Detroit: Gale, 2012. "The Milky Way." //WMAP's Universe//. NASA, 28 June 2010. Web. 06 Mar. 2012. . Vergano, Dan. "Galaxy Bracketed by Big Bubbles." //USA Today// 10 Nov. 2010: 05A. Web. 6 Mar. 2012.
 * Sample:**


 * Your Source List:**

"Exobiology." //The Columbia Encyclopedia//, 6th ed. Columbia University Press, 2000. Reproduced in Kids InfoBits. Detroit: Gale, 2012. Freudenrich, Ph.D., Craig. "How Aliens Work" 15 May 2001. HowStuffWorks.com.  13 March 2012. Kondo, Yoji. "Kepler and the Search for Life in Our Galaxy." //NASA-Home.com//. National Aeronautics and Space Adminstration. September 15, 2009. Web. 8 Mar. 2012 []

**Topic: Research Focus**
 * What is your topic?**
 * State the focus of your research: We are researching the Possibility of Life on other Planets**

**Notes** ==== Include notes, statistics and facts that you will use to write your final paper. You may want to label sections of your notes to help you be more organized as you write. As you take notes from a source, you should list the source citation in the Works Cited section above. ====

[|Mars]. Credit: NASA For centuries, men have pondered the possibility of life on other planets and tried to prove its existence. Even before the first shuttle or probe was launched, stories of life on other planets and life invading our own [|planet], were published prolifically. Whether it’s [|a] desire to connect with others or a burning curiosity to know whether we are truly alone, the question of life on other planets fascinates people from every walk of life. An article on extraterrestrial life would not be complete without discussing Mars. Mars has been the biggest focus of the ongoing search for life on other planets for decades. This is not just a wild assumption or fancy; there are several reasons why scientists consider Mars the best place to look for extraterrestrial life. One reason why many people, including scientists, look to Mars as a possible source of life is because they believe there may be water on the planet. Since the [|telescope] was first invented, astronomers have been able to see the channels in the terrain that look like canals or canyons. Finding water on a planet is vitally important to proving that life exists there because it acts as a solvent in chemical reactions for [|carbon]-based life. Another reason astronomers consider Mars as a likely location for life is because there is a good possibility that Mars is in the habitable zone. The habitable zone is a theoretical band of space a certain distance from [|the Sun] in which conditions are optimal for the existence of carbon-based life. Unsurprisingly, Earth is in the middle of the habitable zone. Although astronomers do not know how far this zone could extend, some think that Mars could be in it. Most astronomers are looking for life that is carbon-based and similar to life on Earth. For instance, the habitable zone only applies to favorable conditions for supporting carbon-based life, and it is definitely possible for forms of life that do not need water to exist. Astronomers do not limit themselves to our [|Solar System] either, suggesting that we should look at different [|solar]systems. Scientists are planning to use interferometry–an investigative technique that implements lasers, which is used in astronomy as well as other fields– to find planets in the habitable zones of other solar systems. Astronomers believe that there are hundreds of solar systems and thousands of planets, which means that statistically the odds are favorable for finding another planet that supports life. While NASA develops better probes, the search for life continues. Until a couple years ago, Mars has always been the top candidate for a [|planet] other than Earth where life might be found. What if Mars disappoints us? Are there other candidates in the solar system? The answer is yes, and the next-best shot at finding extra-terrestrial life forms is on Europa, a moon of the planet Jupiter. Right now, there is no other body in the solar system that attracts as much scientific attention as this bright strange-looking moon, the smallest of Jupiter's four large satellites. Shown below, top to bottom (and as you would approach them moving outward from Jupiter) are Io, Europa, Ganymede and Callisto. Europa seems like a good bet. Life might be a bit strange, but perhaps not a lot stranger than the life forms recently found around hot vents in the abyssal ocean. [|Liquid] water and sources of [|energy] are the essential prerequisites for Life. Europa might well have them. Strong tidal[| heat]could keep the inside of Europa warm enough to have liquid water beneath a layer of ice. Therefore, any [|organic compounds] would be mobile, in water. They could interact. Let's have a closer look at Europa as a possible host of Life. Europa is the fourth largest moon of Jupiter and the sixth largest moon in the solar system. Europa's surface is covered with ice. From the pictures taken by Galileo (the space craft, not the astronomer), its surface looks like broken glass that is repaired by icy glue oozing up from below. Low ridges, straight and curved, crisscross the surface. Flows and fractures, pits and frozen "puddles" - all hint at a unique geologic history. Due to its smooth surface, it is the brightest moon is the solar system. It is quite unlike its fellow moons Callisto and Ganymede with their heavily cratered crusts. Europa has almost a complete absence of craters as well as almost no vertical relief. This interesting feature makes it difficult to find out the age of this moon. Geologists determine the relative age of a surface by counting the number of [|impact craters]. We all know our Moon has many craters. It suggests that our moon has been geologically inactive for about 4000 million years. In contrast, there is very little evidence of impacts on the surface of Europa. Unless Europa is fortunate enough to somehow avoid the impacts suffered throughout the rest of the solar system, it must have gone through some kind of geological process that erased the evidence of almost all of those impacts. Europa has an icy crust that has been severely fractured, as indicated by the dark linear, curved, and wedged-shaped bands seen in images of the surface. These fractures have broken the crust into plates as large as 30 kilometers (18.5 miles) across. Areas between the plates are filled with material that was probably icy slush contaminated with rocky debris. Some individual plates were separated and rotated into new positions. By studying Europa's density we can tell that it has a shell of water ice, parts of which could be liquid. Models of Europa's interior show that beneath a thin 5 km (3 miles) crust of water ice, Europa may have oceans as deep as 50 km (30 miles) or more. There is some evidence indicating that Europa may be slushy just beneath the icy crust and possibly even warmer at greater depths. The evidence includes a strangely shallow impact crater, chunky textured surfaces like icebergs, and gaps where new icy crust seems to have formed between continent-sized plates of ice. Thus, much of the evidence points to a mobile surface provided by liquid water. Liquid water, scientists believe, could exist below the surface because of internal tidal heating from [|gravitational] interactions with Jupiter and the other Galilean moons. (The Galilean moons are the four shown above, so named because they were first observed by Galileo.) Another planetoid mentioned in connection with Life in the solar system is Titan, the largest of the moons of Saturn. Titan has an [|atmosphere] largely made up of nitrogen, with less than one percent of [|methane]. The surface pressure of Titan's atmosphere is higher than that of Earth, but the [|temperature] is extremely cold. A rich assortment of organic [|molecules] is found in Titan's atmosphere, as products of the [|ammonia]/[|methane] chemistry. The mixture includes [|hydrogen] cyanide, a compound in the path to the synthesis of [|amino acids]. This finding has led to speculations that primitive life forms might be present. The low temperatures on this satellite make it unlikely. Are there other forms of life in the universe? The scientific search for extraterrestrial life forms has been bolstered by two recent discoveries. First, the discovery of life forms in exotic environments on Earth indicates that life is very hearty and can adapt to the strangest and most hostile environments. Second, astronomers found [|planets] orbiting stars besides our sun -- over 50 extrasolar planets have been discovered as of 2001. Are there [|alien life] forms on any of these planets? ��­ ��­If alien life does exist, what might it be like? Would it be simple forms of life such as bacteria, viruses or algae, or more advanced, multi-cellular creatures, perhaps even intelligent beings? Would [|aliens] be animals, plants or have characteristics of both? Would they have arms and legs and walk upright as we do? Would they depend upon vision as their primary sense or use another way to gather information about their surroundings? Would they "breathe" oxygen or some other gas? Speculation about [|aliens] has typically been left to science-fiction authors, science-fiction readers and Hollywood writers and directors. In this article, we will examine astrobiology, the scientific search for extraterrestrial life. We'll apply what we have learned about life on Earth to speculate about what alien life forms might be like.

Kepler-22b's radius is roughly 2.4 times the radius of Earth. Its mass and surface composition remain unknown,[7home][6home] with only some very rough estimates established: It has less than 124 Earth masses at the 3 sigma confidence limit, and less than 36 Earth masses at 1 sigma confidence.[9home] It is thought that the object has a mass similar to that of Neptune[10home]), ~35 Earth masses[11home]. There are the possibilities that it could be an "ocean-like" world with only some 10 Earth masses.[11home] It might also be comparable to GJ 1214 b in terms of radius, but Kepler-22b, unlike that planet, is in the habitable zone. If it has an Earth-like density (5.515 g/cm3) then it would contain 13.8 Earth masses,[note 2home] while its surface gravity would be 2.4 times Earth's.[note 3home] Since Kepler-22b is substantially larger than the earth, it is likely to have a different composition, and depending on its actual mass, may be rocky, liquid, or gaseous[7home]; the latter would likely be the same as Kepler-11f, the smallest known gas planet. If it is mostly ocean with a small rocky core, Natalie Batalha, one of the scientists on the project, speculated "it's not beyond the realm of possibility that life could exist in such an ocean."[12home] This possibility of life has spurred SETI to perform research on top candidates for extraterrestrial intelligence.[13home] However, if the planet's carbon cycle has ceased due to lack of oceans and plate tectonics, Kepler-22b may turn out to be a searing, sterile super-Venus. NASA's Kepler mission has confirmed its first planet in the "habitable zone," the region where liquid water could exist on a planet�s surface. Kepler also has discovered more than 1,000 new planet candidates, nearly doubling its previously known count. Ten of these candidates are near-Earth-size and orbit in the habitable zone of their host star. Candidates require follow-up observations to verify they are actual planets. The newly confirmed planet, Kepler-22b, is the smallest yet found to orbit in the middle of the habitable zone of a star similar to our sun. The planet is about 2.4 times the radius of Earth. Scientists don't yet know if Kepler-22b has a predominantly rocky, gaseous or liquid composition, but its discovery is a step closer to finding Earth-like planets. Previous research hinted at the existence of near-Earth-size planets in habitable zones, but clear confirmation proved elusive. Two other small planets orbiting stars smaller and cooler than our sun recently were confirmed on the very edges of the habitable zone, with orbits more closely resembling those of Venus and Mars. "This is a major milestone on the road to finding Earth's twin," said Douglas Hudgins, Kepler program scientist at NASA Headquarters in Washington. "Kepler's results continue to demonstrate the importance of NASA's science missions, which aim to answer some of the biggest questions about our place in the universe." Kepler discovers planets and planet candidates by measuring dips in the brightness of more than 150,000 stars to search for planets that cross in front, or "transit," the stars. Kepler requires at least three transits to verify a signal as a planet. "Fortune smiled upon us with the detection of this planet," said William Borucki, Kepler principal investigator at NASA Ames Research Center at Moffett Field, Calif., who led the team that discovered Kepler-22b. "The first transit was captured just three days after we declared the spacecraft operationally ready. We witnessed the defining third transit over the 2010 holiday season." The Kepler science team uses ground-based telescopes and the Spitzer Space Telescope to review observations on planet candidates the spacecraft finds. The star field that Kepler observes in the constellations Cygnus and Lyra can only be seen from ground-based observatories in spring through early fall. The data from these other observations help determine which candidates can be validated as planets. Kepler-22b is located 600 light-years away. While the planet is larger than Earth, its orbit of 290 days around a sun-like star resembles that of our world. The planet's host star belongs to the same class as our sun, called G-type, although it is slightly smaller and cooler. Of the 54 habitable zone planet candidates reported in February 2011, Kepler-22b is the first to be confirmed. This milestone will be published in The Astrophysical Journal. The Kepler team is hosting its inaugural science conference at Ames Dec. 5-9, announcing 1,094 new planet candidate discoveries. Since the last catalog was released in February, the number of planet candidates identified by Kepler has increased by 89 percent and now totals 2,326. Of these, 207 are approximately Earth-size, 680 are super Earth-size, 1,181 are Neptune-size, 203 are Jupiter-size and 55 are larger than Jupiter. The findings, based on observations conducted May 2009 to September 2010, show a dramatic increase in the numbers of smaller-size planet candidates. Kepler observed many large planets in small orbits early in its mission, which were reflected in the February data release. Having had more time to observe three transits of planets with longer orbital periods, the new data suggest that planets one to four times the size of Earth may be abundant in the galaxy.