Vocabulary Quiz - VocabForce

1. star

luminous celestial body made of hot gases

brightness change due to rotation

sun's outer atmospheric layer above the photosphere

graph representing orbital motion

2. dwarf star

intense burst of solar radiation

standard plane for measurements

small, low-mass star, often red or brown

physics governing celestial bodies and universe

3. revolution period

edge of a celestial body's disk

time taken for one orbit

body similar to planets

projection of Earth's equator onto celestial sphere

4. aspect

reflectivity of a surface, ratio of reflected to incident light

angle between observer, object, and reference point

bright region on the Sun's surface

closest point of Moon to Earth

5. deep-sky object

distant astronomical objects beyond solar system

standard plane for measurements

path of celestial body around another in ellipse

apparent distance between objects in view

6. retrograde motion

curve representing stars of same age

highest point a celestial object reaches in sky

planet appears to move backward in sky

lowest point beneath observer

7. celestial mechanics

study of motion of celestial objects

time measure in orbital mechanics

stellar explosion increasing brightness

point where orbit crosses celestial plane moving north

8. metallicity

loss of light passing through Earth's atmosphere

planet orbiting a star outside the solar system

center of mass of two or more orbiting bodies

abundance of elements heavier than helium

9. open cluster

point where Earth's axis intersects celestial sphere

movement in the direction of rotation

loosely bound star group

longest radius of an ellipse orbit

10. break-up velocity

one object always faces its partner

velocity causing a celestial body to disintegrate

faint glow from dust in solar system

central region of the Milky Way galaxy

11. asteroid

study via telescopes

small rocky body orbiting the Sun, smaller than planets

bright central region of some galaxies, high energy emissions

orbit with zero inclination

12. synodic period

mass bends light from distant objects

study of cosmic dust and its effects

angular distance north or south of celestial equator

time between consecutive alignments

13. degenerate star

period between recurring celestial configurations

boundary where magnetic forces balance plasma inertia

closest point in orbit

dense stellar remnant like white dwarf or neutron star

14. facula

star exhibiting sudden brightness increases

galaxy luminosity and rotation link

bright region on the Sun's surface

large planet like Jupiter or Saturn

15. apparent magnitude

surface marking distinguished by reflectivity differences

imaginary line through Earth's poles

alignment of three celestial bodies in a straight line

brightness of object as seen from Earth

16. planemo

secondary satellite orbiting a satellite

gravity experienced at a celestial body's surface

large celestial body orbiting a star

celestial body capable of nuclear fusion

17. accretion disk

rotating disk of matter spiraling into a celestial body

line dividing daylight and darkness

central dense region of a spiral galaxy

small planetary object

18. obliquity

axial tilt of a planet or star

graph plotting stars' brightness vs. temperature

frequent meteors from same source

rotation speed leading to shape deformation or breakup

19. celestial sphere

imaginary sphere with stars fixed on its inside

reference point for coordinates

network or complex system of interconnected parts

smaller galaxy orbiting a larger one

20. redshift

stars that appear stationary from Earth's perspective

shift toward longer wavelengths indicating recession

movement in the direction of rotation

wobble causing shifting equinox points over time

Vocabulary Quiz:

1. star

2. dwarf star

3. revolution period

4. aspect

5. deep-sky object

6. retrograde motion

7. celestial mechanics

8. metallicity

9. open cluster

10. break-up velocity

11. asteroid

12. synodic period

13. degenerate star

14. facula

15. apparent magnitude

16. planemo

17. accretion disk

18. obliquity

19. celestial sphere

20. redshift

Select vocabulary category you want to browse:

Vocabulary Quiz:

1. star

2. dwarf star

3. revolution period

4. aspect

5. deep-sky object

6. retrograde motion

7. celestial mechanics

8. metallicity

9. open cluster

10. break-up velocity

11. asteroid

12. synodic period

13. degenerate star

14. facula

15. apparent magnitude

16. planemo

17. accretion disk

18. obliquity

19. celestial sphere

20. redshift

Select vocabulary category you want to browse:

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