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.
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"
Picture of a planet which is almost finished its forming process "swimming" through gases and dusts surrounding its mother star. The planet might pull some gases and dusts and form its atmosphere which could disintegrate away when it gets closer to the star. From this process, gas giants could turn in to rocky planets.
As I learned from the Ay20 class today, Kepler mission has found more than 1200 planet candidates. One quarter of that amount are expected to be "super-earth." Several studies suggest that those rocky planets might be a result of failed formation of Jupiter-sized gas giants.
Uranus has an uncanny characteristic of rotation axis making an angle 98 degree with the axis perpendicular to the solar system plane. In other words, it turns sideway. No other planet has such a huge angle like this, for example, Jupiter is at 3 degree, Earth is at 23 degree, and Saturn and Neptune rotates at 29 degree. How could Uranus get this special configuration?
As a first part of the how-to-be-an-astronomer writing project, this post contains my initial impression on astronomer career path. Basically, I am trying to guess how could one can be a professional astronomer? Well, I am pretty sure that it is not by a lottery. When does one have to make a decision to become a star gazer? Also, how much knowledge one has to know?
The video above is taken with a special low-light 4K-camera by the crew of expedition 28&29 of the International Space Station (ISS) from August to October, 2011.
If you wonder where the shooting locations are, here is the list in order of appearance:
1. Aurora Borealis Pass over the United States at Night
2. Aurora Borealis and eastern United States at Night
3. Aurora Australis from Madagascar to southwest of Australia
4. Aurora Australis south of Australia
5. Northwest coast of United States to Central South America at Night
6. Aurora Australis from the Southern to the northern Pacific Ocean
7. Halfway around the World
8. Night Pass over Central Africa and the Middle East
9. Evening Pass over the Sahara Desert and the Middle East
10. Pass over Canada and Central United States at Night
11. Pass over Southern California to Hudson Bay
12. Islands in the Philippine Sea at Night
13. Pass over Eastern Asia to Philippine Sea and Guam
14. Views of the Mideast at Night
15. Night Pass over Mediterranean Sea
16. Aurora Borealis and the United States at Night
17. Aurora Australis over Indian Ocean
18. Eastern Europe to Southeastern Asia at Night
FYI, aurora borealis are the northern lights while aurora australis are the southern lights. Both of them have almost identical features.
In this week of Ay20, we learn about the mechanism of how a star is formed. Picture above is an artist's interpretation of the stage while a star is formed. The proto-star sits in the middle surrounded by a cloud of mass accreted into the star forming the accretion disk. Two yellow jets of mass are excreted from the star to maintain the angular momentum. Here, we solve problem number 4 on the worksheet "The Formation of Stars" located here.
Astronomers use The Very Large Telescope (VLT) to take a picture of a giant star which is classified as a super rare type called the yellow supergiant. It is the most detailed picture and is the first time to see two layers of dust around the supergiant. The star and its dust are so similar to a fried egg that astronomers give its a nickname, "Fried Egg nebular."
