Having nothing to do with trigonometry, what type of parallaxes use the width of absorption lines to estimate the star's luminosity and size and distance?
A.bolometric
B.photometric
C.spectroscopic
D.holographic
E.video metric
You can find the answer here:
http://www.astronomynotes.com/starprop/s13.htm
Reading it would be better than if I just told you the answer.
To find the answer, we need to understand the concepts mentioned in the question. In this case, the question asks about which type of parallaxes use the width of absorption lines to estimate a star's luminosity, size, and distance.
To get started, let's briefly define the terms:
1. Parallax: Parallax is the apparent shift in the position of an object when viewed from different perspectives. In astronomy, parallax is used to determine the distance of stars.
2. Absorption lines: Absorption lines are dark lines observed in a star's spectrum. They are formed when the light from a star passes through its atmosphere and is absorbed by specific elements or molecules.
Now, let's evaluate the given options:
A. Bolometric parallaxes: Bolometric parallaxes include the total energy radiated by a star across all wavelengths. This does not directly involve the width of absorption lines.
B. Photometric parallaxes: Photometric parallaxes involve measuring the star's brightness in different wavelengths of light. This also does not directly involve the width of absorption lines.
C. Spectroscopic parallaxes: Spectroscopic parallaxes use the width of absorption lines to estimate a star's luminosity, size, and distance. This option matches the description in the question.
D. Holographic parallaxes: Holographic parallaxes do not exist in the context of astronomy and are unrelated to the width of absorption lines.
E. Videometric parallaxes: Videometric parallaxes also do not exist in the context of astronomy and are not related to the width of absorption lines.
Based on this analysis, the correct answer is C. spectroscopic parallaxes.
To further understand the topic and confirm the answer, you can refer to the provided link: http://www.astronomynotes.com/starprop/s13.htm. Reading the information provided in the link will help you gain a more comprehensive understanding of spectroscopic parallaxes and their use in estimating a star's properties.