Sample Essay on Astronomy

Astronomy

Astronomers focus on distant and small objects using telescopes. Telescopes are machines that collect light that helps to focus on an image. A small astronomical telescope is made up of the objective lens, the eyepiece, and the focal point. The objective lens refracts or bends parallel light rays causing them to converge at a particular point to focus on a specified object. The central point is the meet point whereby the rays are refracted. The eyepiece is the part that positions the image in a way that is easy for the viewer to have a good field of view. It allows the eye to view the image comfortably for an extended period.

The distance between stars is measured by a filar micrometer. The micrometer has two fine parallel wires that are movable by the observer. While measuring the distance between the stars, the observer places one wire over one star of interest and moves the other wire to the second star. The distance between the two wires is the angular distance between the two stars. A HR diagram is used by astronomers to classify stars. The diagram classifies the stars according to their color, temperature, luminosity, and evolutionary stage. The figure below illustrates the classification of stars by the HR diagram.

Figure 1. HR Diagram

Figure 1. HR Diagram

http://www.astro.cornell.edu/academics/courses/astro201/images/hr_diagram.gif

Light curves are used to determine the type of binary star system that is observed. The brightness of the curve that describes an eclipsing binary orbit is measured from 0.0 to 1.0. The stars appear based on the amount of brightness that is available. Therefore, at some point of a light curve, two stars in close orbit around each other. The difference in the intensity of the light curve determines the binary starts that are caused by one star passing in front of the other.