Aaminah Azhar
Astrobiology Spring 2015
Test 1
1. Name and describe five important steps in the formation of planets based on our current scientific understanding.
a) Star and planet formation starts inside a collapsing cloud of gas and dust inside a bigger cloud called a nebula. Because of gravity pulling materials in the collapsing cloud closer together, the center of the cloud gets increasingly more compressed and because of this get hotter. The dense hot core of this collapsing cloud becomes the kernel of a new star.
b) Next motions inside the cloud cause it to start churning. As the cloud gets even more compressed most of the materials in the cloud begin rotating in the same direction. The cloud eventually flattens into a protoplanetary …show more content…
This is not necessarily true, in actuality the Earth and the Sun both orbit their common center of mass. Since the Sun is so much more massive than the Earth the center of mass is in the Sun, causing it to wobble.
b) The planets orbit the center of mass (located in the star) while the star also orbits this center of mass (located within itself). The planet experiences a large orbit while the star only experiences a slight wobble. This is due to the fact that the gravitational forces acting on the star and extrasolar planet are the same but the planet has a much greater acceleration while the star does not.
c) The Radial Velocity/Doppler/Wobble method is used to find extrasolar planets by noticing their gravitational effect on the star’s they orbit. Smaller planets have a smaller effect on their sun while bigger planets have a much bigger effect on their sun.
d) Astronomers measure this wobble by using spectroscopy. The spectrum is red when a star is moving away from us. The spectrum is blue when a planet is moving towards us. By mapping the stars orbit we can see that it is affected by an …show more content…
Describe five key aspects pertinent to the Kepler mission. (Please feel free to consult the Kepler website.)
a) Some of the objectives of the Kepler Mission include: determining the abundance of terrestrial and larger planets in/near the habitable zone around stars. The distribution of sizes and shapes of the orbits of these extrasolar planets. And, determine the properties of the stars that the planets orbit. b) The presence of extrasolar planets can be detected by measuring the change in brightness of a star’s light. When a planet orbits around a star, the planet covers some of the star, and the measured brightness of the star decreases by a fraction of a percent. This fraction of a percent, when observed consistently over a set time period, confirms the presence of extrasolar planets.
c) Kepler 10 is the first terresterial planet that was ever discovered outside of our solar system. It is a little more than 3 times more massive than our Earth. However it is far to close orbiting to its star that it could not sustain life. It is hypothesized to be a lava world.
d) Kepler-22b, was the first planet, discovered by the Kepler mission of course, that is just the right temperature (in the habitable zone). Because of its size it could quite possibly be a surface covered with water; a water world. There is no way to confirm that water exists on the surface of
Astrobiology Spring 2015
Test 1
1. Name and describe five important steps in the formation of planets based on our current scientific understanding.
a) Star and planet formation starts inside a collapsing cloud of gas and dust inside a bigger cloud called a nebula. Because of gravity pulling materials in the collapsing cloud closer together, the center of the cloud gets increasingly more compressed and because of this get hotter. The dense hot core of this collapsing cloud becomes the kernel of a new star.
b) Next motions inside the cloud cause it to start churning. As the cloud gets even more compressed most of the materials in the cloud begin rotating in the same direction. The cloud eventually flattens into a protoplanetary …show more content…
This is not necessarily true, in actuality the Earth and the Sun both orbit their common center of mass. Since the Sun is so much more massive than the Earth the center of mass is in the Sun, causing it to wobble.
b) The planets orbit the center of mass (located in the star) while the star also orbits this center of mass (located within itself). The planet experiences a large orbit while the star only experiences a slight wobble. This is due to the fact that the gravitational forces acting on the star and extrasolar planet are the same but the planet has a much greater acceleration while the star does not.
c) The Radial Velocity/Doppler/Wobble method is used to find extrasolar planets by noticing their gravitational effect on the star’s they orbit. Smaller planets have a smaller effect on their sun while bigger planets have a much bigger effect on their sun.
d) Astronomers measure this wobble by using spectroscopy. The spectrum is red when a star is moving away from us. The spectrum is blue when a planet is moving towards us. By mapping the stars orbit we can see that it is affected by an …show more content…
Describe five key aspects pertinent to the Kepler mission. (Please feel free to consult the Kepler website.)
a) Some of the objectives of the Kepler Mission include: determining the abundance of terrestrial and larger planets in/near the habitable zone around stars. The distribution of sizes and shapes of the orbits of these extrasolar planets. And, determine the properties of the stars that the planets orbit. b) The presence of extrasolar planets can be detected by measuring the change in brightness of a star’s light. When a planet orbits around a star, the planet covers some of the star, and the measured brightness of the star decreases by a fraction of a percent. This fraction of a percent, when observed consistently over a set time period, confirms the presence of extrasolar planets.
c) Kepler 10 is the first terresterial planet that was ever discovered outside of our solar system. It is a little more than 3 times more massive than our Earth. However it is far to close orbiting to its star that it could not sustain life. It is hypothesized to be a lava world.
d) Kepler-22b, was the first planet, discovered by the Kepler mission of course, that is just the right temperature (in the habitable zone). Because of its size it could quite possibly be a surface covered with water; a water world. There is no way to confirm that water exists on the surface of