Vocabulary Quiz - VocabForce

1. color index

layer separation in planets

longest radius of an ellipse orbit

center of mass of two or more orbiting bodies

measure of star's color and temperature differences

2. decretion disk

star and its planets or companions

sudden magnetic field change in solar wind

longest diameter of an elliptical orbit

material ejected outward from a star as disk

3. heliopause

tilt of orbit's plane

closest point of planet to Sun

loosely bound star group

boundary where solar wind ceases

4. solar day

time from one sunrise to the next

star trail from gravitational stripping

spread of velocities in a system

material between stars in a galaxy

5. nuclear star cluster

compact star group at galaxy center

study of motion of celestial objects

large group of galaxy clusters

imaginary line around which an object spins

6. coronal mass ejection

closest or furthest point in an orbit around a focus

massive burst of solar plasma and magnetic fields

speed toward or away from observer

gravity experienced at a celestial body's surface

7. photosphere

Sun's visible surface layer

dense stellar remnant like white dwarf or neutron star

brightness change due to rotation

star with faint spectral lines

8. selenocentric

centered around the Sun

total energy emitted by an object

thermal radiation from early universe

small planetary object orbiting Sun

9. occultation

one celestial body blocking another

centered around the Sun

protoplanetary disk around a young star

unit of distance (~3.26 light-years)

10. stellar evolution model

boundary where solar wind ceases

theoretical framework of star development

large planet like Jupiter or Saturn

one celestial body blocking another

11. topocentric

perspective from Earth's surface

any physical entity in space observed visually or otherwise

path of celestial body around another in ellipse

galaxy with exceptionally high star formation

12. extinction

rotation speed leading to shape deformation or breakup

shorter diameter of an ellipse

point where Earth's axis intersects celestial sphere

loss of light passing through Earth's atmosphere

13. atmosphere

gaseous envelope surrounding a planet or star

boundary where magnetic forces balance plasma inertia

extremely large black hole at galaxy's core

parameters defining an orbit

14. ecliptic coordinate system

time between similar moon phases

celestial coordinates based on the ecliptic plane

planet closer to the Sun than Earth

orbit aligning with a body's rotation

15. obliquity

axial tilt of a planet or star

eccentricity of an orbit

region beyond Earth's atmosphere

emitting object detectable in radio wavelengths

16. debris disk

gradual change in a celestial body's axis orientation

apparent distance between objects in view

longest radius of an ellipse orbit

material around star from collisions or remnants

17. small Solar System body

spherical collection of old stars

region between Mars and Jupiter with numerous asteroids

path of celestial object around a star

minor celestial object like asteroid or comet

18. centaur

time between similar moon phases

small Solar System body between asteroids and comets

vernal equinox occurring in March

physics governing celestial bodies and universe

19. galactic coordinate system

study of galaxies and their structures

related to stars

flat surface containing orbit

sky coordinate system centered on the galaxy

20. field star

contraction under gravity forming stars or structures

star not part of a star cluster

region of small icy bodies beyond Neptune

apparent shift due to Earth's movement

Vocabulary Quiz:

1. color index

2. decretion disk

3. heliopause

4. solar day

5. nuclear star cluster

6. coronal mass ejection

7. photosphere

8. selenocentric

9. occultation

10. stellar evolution model

11. topocentric

12. extinction

13. atmosphere

14. ecliptic coordinate system

15. obliquity

16. debris disk

17. small Solar System body

18. centaur

19. galactic coordinate system

20. field star

Select vocabulary category you want to browse:

Vocabulary Quiz:

1. color index

2. decretion disk

3. heliopause

4. solar day

5. nuclear star cluster

6. coronal mass ejection

7. photosphere

8. selenocentric

9. occultation

10. stellar evolution model

11. topocentric

12. extinction

13. atmosphere

14. ecliptic coordinate system

15. obliquity

16. debris disk

17. small Solar System body

18. centaur

19. galactic coordinate system

20. field star

Select vocabulary category you want to browse:

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