Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 25: Problem 4

Suppose you saw an object in the sky that you suspected might be a quasar. What sort of observations might you perform to test your suspicion?

Short Answer

Expert verified
Identify if the object shares characteristics of a point source, check if it gives off strong radio emissions, measure its redshift, observe the variability of emissions and finally, conduct spectroscopic observations.

Step by step solution

01

Point Source Identification

The first step would be to notice if the suspected object resembles a point source of light, similar to the way stars appear. Quasars are compact objects and are often mistaken for stars due to their appearance. Using tools such as a telescope might aid in this observation.
02

Radio Emission Observations

The next step is to perform radio wave observations as quasars are known to emit strong radio waves. This can be done using a radio telescope, which operates commonly within the radio frequency range of the electromagnetic spectrum.
03

Redshift Determination

This step involves the measuring of the redshift of the suspected object. Quasars are often characterized by a high redshift, meaning they have a significant shift towards the red end of the spectrum. This indicates that the object is moving away from the observer at a high speed, consistent with the expanding universe theory.
04

Variability of Emission

Would also recommend checking the variability of the emission from the object. Quasars are known to have rapid and large variations in brightness over short periods, which can be indicative of its small size.
05

Spectroscopic Identification

The final step is conducting spectroscopic observations to identify the object accurately. Quasars have unique emission spectra with broad emission lines that indicate the presence of certain elements. The broad emission lines would signal the presence of a quasar.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Observations of a certain galaxy show that stars at a distance of \(16 \mathrm{pc}\) from the center of the galaxy orbit the center at a speed of \(200 \mathrm{~km} / \mathrm{s}\). Use Newton's form of Kepler's third law to determine the mass of the central black hole.

Quasar PC \(1247+3406\) is presently about \(25.9\) billion lightyears from Earth. Explain how it is possible for astronomers to see this quasar, even though light travels at a speed of 1 light-year per year.

What are head-tail sources? How do they provide evidence that double radio sources include jets of fast-moving particles?

Relativistic Redshift. Access the Active Integrated Media Module "Relativistic Redshift" in Chapter \(2.5\) of the Universe Web site or eBook. Use this to calculate the redshift and recessional velocity of quasar in whose spectrum the \(\mathrm{H}_{\mathrm{\alpha}}\) emission line of hydrogen (unshifted wavelength \(656 \mathrm{~nm}\) ) appears at a wavelength of (a) \(937 \mathrm{~nm}\) and (b) \(5000 \mathrm{~nm}\).

The Seyfert galaxy NGC 1275 is actually two galaxies that are colliding. Images of \(\mathrm{NGC} 1275\) show a number of globular clusters with a distinctive blue color. Explain how this color shows that these clusters formed relatively recently, perhaps as a result of the collision.
See all solutions

Recommended explanations on Physics Textbooks

Waves Physics

Read Explanation

Geometrical and Physical Optics

Read Explanation

Rotational Dynamics

Read Explanation

Torque and Rotational Motion

Read Explanation

Measurements

Read Explanation

Kinematics Physics

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free