Lab Brightness of Stars Apparent and Absolute Magnitudes Magnitude (2).doc

Lab Brightness of Stars Apparent and Absolute Magnitudes Magnitude (2).doc

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Lab-Brightness of Stars Apparent and Absolute Magnitudes Magnitude Objective: To study apparent and absolute visual magnitude of stars and use them to measure the distance and the nature of the stars. Discussion Part A: Apparent magnitude and brightness The number of stars an individual can see in the night sky depends on several factors, such as the brightness of stars, sky conditions, and the quality of the observer’s eyes. Man’s desire to identify stars with reliability required the development of a technique to assist him in locating stars in addition to the established celestial coordinates. A system of stellar labeling was developed by assigning numbers based on the relative brightness of stars and is called the magnitude system. A magnitude is a number assigned to celestial object that is a measure of the object’s relative brightness. Brightness is the individual response to the light energy received from a star. The brightness is related to the luminosity or total energy emitted by a star. Differences in brightness occur because all stars do not produce the same amount of light energy, and because of the large distribution of stellar distances with respect to earth. The apparent magnitude is the brightness of stars as seen from earth, symbolized by letter m . The more negative or smaller the magnitude, the brighter the star, and the more positive or larger the magnitude, the dimmer the star. By itself the apparent magnitude cannot be used to measure the distance that a star is from the Earth. Stars vary in intrinsic brightness. It’s like comparing a candle to a light bulb. The candle is intrinsically faint whereas a light bulb is intrinsically bright. That is, if you place both the candle and light bulb the same distance from your eye the candle will appear fainter than the light bulb. However, if you place the candle much closer to your eve it will appear as bright as the light bulb as the light bulb at a much farther distance.
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern