## Sunday, December 4, 2011

### Spiral Arms In a Star's Disk Leads To Planets

 Credit: www.futurity.org
Picture above shows a disk of gas and dust circulating around a Sun-like star. A structure like spiral arms could mean the existence of planets which haven't been detected yet. Computer simulation has shown that gravitational force from a planet in the disk could disturb the trajectory of gases and dusts which form spiral arms.

## Friday, December 2, 2011

### Looking For Light Pollution But Not From This Earth

 Earth at Night Credit: C. Mayhew & R. Simmon (NASA/GSFC), NAA/NGDC, DMSP Digital Archive

Astronauts orbiting the Earth often look upon our planet illuminated by lights in night zone. Researchers start to think that scientists should be able to detect light from other civilizations too. Many scientific fictions had ever dreamed about a planet filled with illuminated cities, for example, the galaxy's capital like Coruscant from Star Wars.

### Dance of a star: Part III - (Problem 7-8)

by Mee Wong-u-railertkun, David Vartanyan, John Pharo

 Credit: www.wikipedia.com
We present the solution to problems from the worksheet "Planet Host Stars Wobble But They Don't Fall Down" (which could be found here.) The outline of this worksheet is as following. First, we are going to see how a planet affects the movement of a star. From that knowledge, we can observe this "weird" characteristic of a star to find exoplanets. In this post, we present solution to question seven and eight.

## Thursday, December 1, 2011

### Dance of a star: Part II - (Problem 4-6)

by Mee Wong-u-railertkun, David Vartanyan, John Pharo

 Credit: ESO
We present the solution to problems from the worksheet "Planet Host Stars Wobble But They Don't Fall Down" (which could be found here.) The outline of this worksheet is as following. First, we are going to see how a planet affects the movement of a star. From that knowledge, we can observe this "weird" characteristic of a star to find exoplanets. In this post, we present solution to question four to six.

### Dance of a star: Part I - (Problem 1-3)

by Mee Wong-u-railertkun, David Vartanyan, John Pharo

We present the solution to problems from the worksheet "Planet Host Stars Wobble But They Don't Fall Down" (which could be found here.) The outline of this worksheet is as following. First, we are going to see how a planet affects the movement of a star. From that knowledge, we can observe this "weird" characteristic of a star to find exoplanets. In this post, we present solution to question one to three.

## Wednesday, November 30, 2011

### Becoming an Astronomer: Alternative Career Arcs

 Credit: www.clipartguide.com
The "Becoming An Astronomer" writing project starts out with a blog about my first impression on being an professional astronomer (here). As a second part, David and John interviewed Professor Richard Ellis about his career and profession (here and here). Professor Ellis is a well-established astronomer but what are other paths? Here is where I come in. In this post, I will examine other astronomy career arcs.

## Saturday, November 26, 2011

### Kepler 18 - the packed system

 Credit: McDonald observatory The graphic shows the orbits of Kepler-18b, c, and d around their star compared to Mercury's orbit. The lower graphic shows the relative size of planets to their star and Earth to our Sun.
Kepler Space Telescope hunting for exoplanets found three planets orbiting a star, Kepler-18, which is 10% larger than our Sun but has only 97% of solar mass. There are still planets yet to discovered in this system. What is special for this system is that the planets are in resonant orbiting path.

Those three planets are called Kepler-18b, c, and d. They orbit their star at very close range, even closer than Mercury which is the closest planet in our solar system. Kepler-18b uses only 3.5 days to orbit around the star. It is approximately 6.9 times Earth's mass and two times larger than our Earth. Thus, it is called "super-earth"