Doppler Shift Ranking Task Paper

Andres Cardoso
5/12/2017
ASTM 101
Ranking Task Paper

In the Doppler shift ranking task, astronomers measure the spectrum of electromagnetic radiation of visible and radio from celestial bodies to determine many attributes of the stars and planets. Some of the attributes that can be observed from measuring the spectrum of electromagnetic radiation are Luminosity distance and Doppler shift. “The equipment work by measuring the wavelength of absorption lines, where the larger absorption line means a longer wavelength and the celestial object is moving away from the observer which is also called a red-shift.”(Measuring Stellar Sizes, CSIRO Australia Telescope National Facility;) While smaller absolution lines means the object is moving closer to the observer which is also called a blue-shift. There are however limitations to the effectiveness of measuring the Doppler shift, such as the earth’s atmosphere which is opaque to certain types of electromagnetic radiation, such that they do not reach the earth.
In Stellar evolution ranking task, astronomers are
This is the case for most galaxies. For distant star astronomers rely on the understanding of stellar evolution which can be roughly estimated once the spectrum of the star is known. This can be used on exoplanets to measure its size based from the orbit and the star in system. “Astronomers also use trigonometric parallax that can be used to measure nearby stars which is the angular shift, called parallx is on angle of a triangle and the distance between 2 vantage points is one side of the triangle.”(Limits to Parallax,CSIRO Australia Telescope National Facility; ) Granted it does come with a limitation that that the angle of parallax can be too small the 2 vantage points must increase the distance between the