CAJ 5: The Flower-shaped Star Shade.

The Kepler Mission is very important in detecting earth-like planets but it is not capable of studying the features of the planet in more detail. As the light of the star is too intense to analyze the orbiting planet. It’s  challenging to observe a planet orbiting another star, because the bigger the distance the paler and dimmer the image. The star is too bright and the planet too close to the star. Even though the atmosphere that would smear the light is not a problem in space (as there is no atmosphere) the light scatter and the diffraction in the telescope are still problems that need to be addressed.


There are many suggestions to resolve this problems but the most obvious and promising one is the flower-shaped star shade. This is an occulting device that blocks the starlight and thus it can not even enter the optical path.One of the major advantages of the star shade is that this construction is feasible with existing technology.  This device helps the telescope to achieve a much more detailed image of the terrestrial bodies around the star. In order to minimize the diffracted light, the distance between the telescope and the star shade must be around 40.000 kilometers. The star shade must be approximately 50 meters in diameter and the optic of the telescope diffraction limited and at least 1 meter in diameter to achieve the deepest shadow.

The star shade and the telescope would be one spacecraft and only in space they would separate and move away from each other. In order to receive the best results possible , the star shade is equipped with small thrusters that help to remain in position while observing the bodies around the star in more detail. The form of the star shade is important. Without the “leafs” around it, the light waves would still be too strong to achieve a detailed image of the planets around it. Scientists worked on this star shade tirelessly, for a long time. After numerous mathematical calculations and several prototypes, they suggested this shape, as it helps to control the fraction of the light.

This invention will help us to discover and analyze planets for liquid water and oxygen. It will help the telescopes to photograph major features of the chosen planets, like oceans or mountains. Another important advantage of this invention is that it is within the budgetary scope of NASA and it is within the reach of existing technology.


http://newworlds.colorado.edu/info/documents/CashNatureJuly2006.pdf

http://www.ted.com/talks/jeremy_kasdin_the_flower_shaped_starshade_that_might_help_us_detect_earth_like_planets?utm_source=facebook.com&utm_content=awesm-bookmarklet&awesm=on.ted.com_c08UP&utm_medium=on.ted.com-facebook-share&utm_campaign=#

CAJ 4: Breaking News: Kepler 186-f

On April 17th, NASA's Kepler Team announced the discovery of a planet in the habitable zone. This is a major step forward in the discovery of an Earth-like planet and a milestone for the Kepler Mission. Until recently, scientists only discovered  planets that were 40 % larger than Earth with similar properties but with the discovery of Kepler-186f, the Team can declare that there are planets similar to Earth in size and are in the habitable zone of their star, outside of our Solar system.

Kepler 186-f is claimed to be a rocky planet but scientists have to calculate the mass and density of the planet. Therefore, further analysis has to be done before drawing a conclusion. As the planet has the right size and is in the middle of the habitable zone of its star, the chance that it has liquid water is high. The temperature of the planet depends also on its atmosphere, for this reason it is not confirmed to be habitable yet.

 The planet is 500 light years away from us. The star that it orbits is half the size and dimmer than our Sun. Kepler 186f orbits its Star every 130 days. The star has  four  other planets ( Kepler186-b,c,d,e) that are all much closer to their Sun. They whiz around their Sun every 3 to 22 days, making them too hot to be habitable.

Scientists refer to Kepler186-f not as Earth-twin but as Earth-cousin. It has many properties that resemble Earth, but it gets less energy from its star than Earth gets from our Sun. On the surface of Kepler-186f the brightness of its star at high noon is only as intense as our Sun would appear for us an hour before sunset.

Only now I start to realize how important this Mission is. My CAJ topic brings, from day to day, new discoveries to light, which are in my eyes, very important historic events.

Descriptive Text - Group Work

Descriptive Text - Boy With The Toy Hand Grenade http://tiana-afterglow.blogspot.co.at/2014/04/descriptive-text-boy-with-toy-hand.html

CAJ 3: Still searching for our new home/ planet categories / Kepler 16-b

Now that I have introduced briefly the Kepler Mission, I want to talk a little bit more about the planet candidates and discoveries that the mission has brought to light.

To categorize the planets, scientist have created a "Periodic Table of Exoplanets". This system  helps the scientists to classify the newly discovered planets into six main categories. They differentiate planets
by mass/size and three temperature subgroups. This makes 18 categories in total. The three temperature groups are cold zone, warm zone (habitable zone) and hot zone. According to mass and size there are 6 groups, which are mercurian, subterran, terran, superterran( these four constitute the terrestrial planets), neptunians and jovians (these are called the gas giants). Mercurian planets are approximately the size of our Moon or Mercury and they are atmosphere-less low mass planets. Subterran planets are comparable to Mars, terrans are planets like the Earth, superterran is the only group for which our solar-system has no example. Neptunian, as the name already tells, is the category in which the planets are as big as Neptune, and jovian planets are in our solar-system Jupiter or Saturn or even bigger.
























On this picture you can see the confirmed exoplanets that are known by the NASA. The number in the
middle of each picture shows how many of these planets have been discovered so far. In the upper right corner you can also see the multiple number of stellar systems.



These are only the confirmed planets. The Kepler Mission has discovered many more planets, which aren't yet confirmed to be one. In order to confirm that a planet candidate is a planet it must regularly orbit a star with the same transit time. For earth like planets in the habitable zone this means that it has to transit a star for three years to make sure it is one.

 This picture shows how many planet candidates the Kepler Mission helped to discover. As you may see, there are many warm superterran planets outside of our solar system, which are particularly interesting for the scientists. They haven't had the chance to take probes or analyze them closer and as there are no superterran planets in our solar system, the scientists are very curious about their features.

In September 2011 the Kepler Mission announced a discovery which was for many science-fiction fans a day to remember. The Kepler Telescope discovered a planet that orbits two suns. This planet is 200 light-years away from Earth. The solar system is called the Kepler 16 and the name of the planet is Kepler 16-b. The planet is outside of the habitable zone and is said to be a cold world without liquid water. It orbits both stars every 226 days. The discovery was made when the Kepler Scientists discovered a second object transiting the main star that turned out to be a second star. It has a smaller orbit and that means that it orbits the main star faster than Kepler 16-b.The stars are both smaller than our sun. The fact that a phenomenon like this exists shows how mysterious and diverse our Universe is. The reason why most science-fiction fans are interested in this is because Star Wars worked with a similar concept, without knowing about the existence of the phenomenon.

Narrative article homework: North-Korea

Kim (12) is sitting on the shoulder of his father, curiously looking in the way everyone else is looking. The boy asks his father, ”Daddy what is going on? Why are we here?” The father’s answer is very simple and straightforward, ”I brought you here for one reason. I want you to learn that disrespecting your country will only lead to death.” The boy looks at the sunken face of his father with disappointment. Soon after a young man appears on a stage in front of the crowd. On his arms are handcuffs and he is followed by two guards. The boy can see the beaten but proud face of the young man on the stage. The son does not ask anymore, he just looks in the eyes of the young man and the young man stares back at him. After the guards announced the accusation, they simply shot the man in the head. At first Kim did not believe what happened and covered his eyes with his hands but his father took his hands and persuaded him to watch further. Nine more persons would follow and Kim had to look in the eye of all of them. While the crowd applauded, Kim’s face was sear and without any emotion. His father told him that this is a lesson he should never forget. Fortunately Kim never did and he is one of the few who could escape from the cruel and unforgiving hands of North-Korea. He is now here to tell his story.