What is a light-year, and how is it defined?
The significance of light year and its definition.
Answer to Problem 1CQ
A light-year is a unit of length used to measure the astronomical distances. It is defined as the distance travelled by the light in
Explanation of Solution
In astronomy, there were no referent points of comparison so that standard units were created for the measurement of distances. A light-year is a unit of length which is used to describe the astronomical distances.
Therefore, a light year is the distance travelled by the light in
Want to see more full solutions like this?
Chapter 12 Solutions
Integrated Science
Additional Science Textbook Solutions
Human Anatomy & Physiology (2nd Edition)
Human Biology: Concepts and Current Issues (8th Edition)
Campbell Essential Biology with Physiology (5th Edition)
Genetic Analysis: An Integrated Approach (3rd Edition)
- 1. A distant galaxy has an apparent magnitude of 10 and is 4,000 kpc away. What is its absolute magnitude? (Round your answer to at least one decimal place.) The difference in absolute magnitude between two objects viewed from the same distance is related to their fluxes by the flux-magnitude relation. FA/FB= 2.51(MB − MA) 2. How does the absolute magnitude of this galaxy compare to the Milky Way (M = −21)?arrow_forwardDescribe two ways of determining the diameter of a star.arrow_forwardExplain the origin of the magnitude designation for determining the brightness of stars. Why does it seem to go backward, with smaller numbers indicating brighter stars?arrow_forward
- How Do We Know? Why is it important that a theory make testable predictions?arrow_forwardIs the Sun an average star? Why or why not?arrow_forwardDo the previous problem again, this time using the information that the Sun is 150,000,000 km away. You will get a very large number of km as your answer. To get a better feeling for how the distances compare, try calculating the time it takes light at a speed of 299,338 km/s to travel from the Sun to Earth and from Alpha Centauri to Earth. For Alpha Centauri, figure out how long the trip will take in years as well as in seconds.arrow_forward
- How Do We Know? Why is astrology a pseudoscience?arrow_forwardWhich of the following statements about stellar parallax is true? A. We observe all stars to exhibit at least a slight amount of parallax. B. Stellar parallax was first observed by ancient Greek astronomers. O C. The amount of parallax we see depends on how fast a star is moving relative to us. D. It takes at least 10 years of observation to measure a star's parallax. OE. The closer a star is to us, the more parallax it exhibits.arrow_forwardProblem 5. Imagine that you observe a star field twice, with a six-month gap between your observations, and that you see the two sets of stars shown below. Which do you think is closest to the observer? Figure 1: Schematic of image of stars A,B, and P taken six months apart. Problem 6. Suppose the angular separation between stars A and B is 0.5 arcseconds. How far would you estimate star P to lie from the observer?arrow_forward
- Use the circumference and speed to figure out how long the Sun takes to go once around the Galaxy (the Sun's period, sometimes called the "galactic year.") Give your answer in Earth years. Be careful with your units.arrow_forwardI need help pleasearrow_forwardWhich of the following WOULD NOT characterizes the type(s) of star we would find at g, m, n, o, and p on the Hertzsprung-Russel Diagram (Figure 4) a. are all smaller than q,i,h. b. fuse hydrogen into helium. c. are called, “the main sequence”. d. fuse He into heavier elements. e. get smaller towards the right sidearrow_forward
- An Introduction to Physical SciencePhysicsISBN:9781305079137Author:James Shipman, Jerry D. Wilson, Charles A. Higgins, Omar TorresPublisher:Cengage LearningAstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStaxFoundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning
- Stars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage LearningHorizons: Exploring the Universe (MindTap Course ...PhysicsISBN:9781305960961Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning