Astronomy Chapter 21 Flashcards
18 Questions
100 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What are constellations?

A group of stars forming a recognizable pattern traditionally named after its apparent form or a mythological figure.

What is the equatorial system used for?

Describing the position of objects outside the solar system.

What does declination represent?

The angular distance of a point north or south of the celestial equator.

What is right ascension?

<p>The distance of a point east of the First Point of Aries, measured along the celestial equator.</p> Signup and view all the answers

What does rotation refer to in astronomy?

<p>The action of rotating around an axis or center.</p> Signup and view all the answers

What is revolution in an astronomical context?

<p>An instance of revolving.</p> Signup and view all the answers

What is axial precession?

<p>A gravity-induced, slow, and continuous change in the orientation of an astronomical body's rotational axis.</p> Signup and view all the answers

What is a mean solar day?

<p>The time between successive passages of the mean sun across the meridian.</p> Signup and view all the answers

What defines a sidereal day?

<p>The time between two consecutive transits of the First Point of Aries.</p> Signup and view all the answers

What is perihelion?

<p>The point in the orbit of a planet, asteroid, or comet at which it is closest to the sun.</p> Signup and view all the answers

What is aphelion?

<p>The point in the orbit of a planet, asteroid, or comet at which it is furthest from the sun.</p> Signup and view all the answers

What is the ecliptic?

<p>A great circle on the celestial sphere representing the sun's apparent path during the year.</p> Signup and view all the answers

What does the plane of the ecliptic refer to?

<p>The imaginary plane containing the Earth's orbit around the sun.</p> Signup and view all the answers

What is a synodic month?

<p>Another term for lunar month.</p> Signup and view all the answers

What is a sidereal month?

<p>The time it takes the moon to orbit once around the Earth with respect to the stars.</p> Signup and view all the answers

What are the phases of the moon?

<p>The shape of the illuminated portion of the Moon as seen by an observer on Earth.</p> Signup and view all the answers

What is a solar eclipse?

<p>An eclipse in which the sun is obscured by the moon.</p> Signup and view all the answers

What is a lunar eclipse?

<p>An eclipse in which the moon appears darkened as it passes into the Earth's shadow.</p> Signup and view all the answers

Study Notes

Constellations

  • Groups of stars that form recognizable patterns, often named after their appearance or mythological figures.
  • The sky is divided into eighty-eight constellations with established boundaries.

Equatorial System

  • The primary system used in astronomy to describe the positions of objects outside the solar system.
  • Compared to altazimuth and ecliptic coordinate systems.

Declination

  • Represents the angular distance of a celestial point north or south of the celestial equator.

Right Ascension

  • Measures distance east of the First Point of Aries along the celestial equator.
  • Expressed in hours, minutes, and seconds.

Rotation

  • Describes the action of an astronomical body rotating around its axis or center.

Revolution

  • Indicates an instance of an object revolving around another body, such as a planet around the sun.

Axial Precession

  • A gradual, continuous change in the orientation of an astronomical body's rotational axis due to gravitational forces.

Mean Solar Day

  • The average time between successive passages of the mean sun across a given meridian.

Sidereal Day

  • The time interval between two consecutive transits of the First Point of Aries.
  • Shorter than a solar day by almost four minutes, accounting for Earth's orbital motion.

Perihelion

  • The point in an orbit where a celestial body (planet, asteroid, comet) is closest to the sun.

Aphelion

  • The point in an orbit where a celestial body is farthest from the sun.

Ecliptic

  • The apparent path of the sun across the celestial sphere throughout the year.
  • Lunar and solar eclipses can only occur when the moon crosses this path.

Plane of the Ecliptic

  • An imaginary plane containing Earth’s orbit around the sun.
  • The sun’s apparent path through the sky lies within this plane yearly.

Synodic Month

  • Another term for the lunar month, the cycle of the moon's phases.

Sidereal Month

  • The duration it takes for the moon to complete one full orbit around Earth relative to the stars.
  • Approximately 27.25 days in length.

Phases of the Moon

  • Refers to the shape of the sunlit portion of the moon as observed from Earth.

Solar Eclipse

  • Occurs when the moon obscures the sun from the perspective of an observer on Earth.

Lunar Eclipse

  • Happens when the moon passes into Earth’s shadow, causing it to appear darkened.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Description

Test your knowledge with these flashcards from Chapter 21 on constellations and the equatorial system. Learn about the key concepts and definitions that shape our understanding of the night sky. Perfect for students looking to reinforce their learning in astronomy.

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser