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A few acknowledgements. When I first started reading about the Kepler mission, the Kepler website proved invaluable. It has a wealth of information, as well as some really good, pre-made and field-tested, material for educators.
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A few acknowledgements. When I first started reading about the Kepler mission, the Kepler websiteproved invaluable. It has a wealth of information, as well as some really good, pre-made and field-tested, material for educators. I’ve borrowed liberally from the Transit Tracks worksheet and Transit Tracks PowerPoint presentation, especially in some of the notes. I also used parts a nice lab, linked here, that covers much of the same material but that is suitable for a slightly more mature audience. I think that I’ve cited sources for all of the images as well as all of the information found in the notes (much of which were not used, but give a bit more information on the topics). If I’m missing a citation that you notice, please let me know.
Transit graphs and extrasolar planets Hope Concannon Teaching Contemporary mathematics conference January 2014
extrasolar planets are hard to detect becausethey are small, dim, and distant
Brown Dwarf and Child Spotted in 2004, the smaller red dot (the planet) is about 3 to 10 times more massive than Jupiter and is spinning around a brown dwarf, which is an object larger than a planet but without enough mass to ignite into a burning star. http://www.eso.org/public/news/eso0515/
The first directly observed exoplanet Mass: eight times the mass of Jupiter Orbital radius: more than 300 AU Temperature: over 2700°F Credit: Gemini Observatory
Radial Velocity Method http://obswww.unige.ch/~udry/planet/Images/doppler.jpg
The Kepler Mission According to NASA, Kepler seeks evidence of Earth-size planets in the habitable zone of Sun-like stars. (Photo : Reuters) An artist's rendition of the Kepler satellite afloat in space.
What is the Habitable Zone? Credit: NASA/Ames/JPL-Caltech
http://eoimages.gsfc.nasa.gov/images/imagerecords/78000/78196/ISS031-E-089012.jpghttp://eoimages.gsfc.nasa.gov/images/imagerecords/78000/78196/ISS031-E-089012.jpg What is this?
Which type of system will make it easier to find planets using transits? • Small diameter planets or large diameter planets? • Small mass planets or large mass planets? • Planets close to their star or planets far from their star? • Face-on orbits or edge-on orbits? • Less massive stars or more massive stars? • Planets with orbits that are closer to circular • or highly elliptical orbits? Credit: NASA/Ames/Caltech.
What do Real transits look like? Light-curve for HD209458b, the first-discovered and best-known transiting planet (from Perryman 2000)
An expanded view… How are the planet’s size and period seen in the light curve?
What do transit graphs reveal? The mathematics of a transit curve
What percent of light is blocked? How is this related to the size of the planet? http://nexsci.caltech.edu/workshop/2007/planet_transit.gif
Kepler’s Third Law The square of the orbital period, T, of a planet is directly proportional to the cube of the semi-major axis, a, of its orbit. If expressed in units T Earth years a AU Solar masses Then
THE ACTUAL KEPLER 4B LIGHT CURVE You try it. Can you determine the radius of the planet and it’s orbital distance from it’s sun? You can get to this data from this link
Temperature of the Planet Planet temperature can be determined from the parent star’s brightness and the planet’s size and orbital distance. http://discovery.nasa.gov/images/missions/kepler/PlanetTempAndSize.jpg
GEOMETRIC PROBABILITY OF TRANSITS solid angle of planet = solid angle of sphere = probability of transit http://ay20class.blogspot.com/2011/11/transit-probability.html
You can also download Kepler Times Series files to analyze yourselves:
Thank you for your attention! Hope Concannon hopeconcannon@ncssm.edu