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🪐Intro to Astronomy
Key Terms

919 essential vocabulary terms and definitions to know for your Intro to Astronomy exam

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M_{BH}- ext{sigma} Relation
21 cm Hydrogen Line
21-cm radio line
51 Pegasi b

A

A-type Star
A-type stars
Absolute Magnitude
Absorption Line Spectra
Absorption Lines
Accretional Heating
Action at a Distance
Active Optics
Active region
Adaptive Optics
Adaptive optics
Aeolian Erosion
Age-Metallicity Relation
Air Cherenkov Telescope
Air Mass
Air Showers
Alpha Centauri
Altazimuth Mount
Ammonium Hydrosulfide
Andromeda Galaxy
Andromeda galaxy
Andromeda-Milky Way Collision
Angular Diameter
Angular Momentum Conservation
Angular Power Spectrum
Angular Resolution
Annular Solar Eclipse
Anthropogenic Greenhouse Effect
Anticyclonic Storm
Aperture Synthesis
Apogee
Apogee
Apollo Missions
Apollo program
Ascending Node
Asteroid Belt
Asteroid belt
Asteroid Composition
Astronomical Measurement
Astronomical Seeing
Asymptotic Giant Branch
Atacama Large Millimeter/submillimeter Array
Atmospheric Circulation
Atmospheric Composition
Atmospheric Escape
Atmospheric Haze
Atmospheric Opacity
Atmospheric Pressure
Atomic Clock
Atomic Excitation
Atomic Hydrogen
Atomic Spectrum
Axial Precession

B

B-type star
B-type Stars
B-V Color Index
Baily's Beads
Balmer Lines
Balmer lines
Balmer Series
Barred spiral galaxy
Barred Spiral Galaxy
Baryogenesis
Baryon Acoustic Oscillations
Baryon Cycle
Baryon cycle
Baryonic Matter
Bayer letter
Beta Decay
Binary Systems
Biosignatures