Vocabulary Quiz - VocabForce

1. major axis

group of stars gravitationally bound

dimming near a star's limb

longest diameter of an elliptical orbit

galaxy without defined shape

2. photosphere

Sun's visible surface layer

large planet composed mainly of gases

dust and gas ring around a star or planet

time for a galaxy to complete an orbit

3. planetesimal

elusive subatomic particle

projection of Earth's equator onto celestial sphere

small building block of planets

gaseous interstellar cloud

4. orbital elements

wide-angle imaging for X-ray telescopes

chemically peculiar star with strong metal lines

stars beginning hydrogen fusion

parameters defining an orbit

5. celestial pole

point where Earth's axis intersects celestial sphere

central region of the Milky Way galaxy

imaginary line through Earth's poles

gravity experienced at a celestial body's surface

6. total solar eclipse

categorization of stars by spectrum

Moon blocks Sun completely

small rocky body orbiting the Sun, smaller than planets

star light reddening caused by dust

7. irregular moon

material around star from collisions or remnants

point where orbit crosses ecliptic

related to equinoxes or occurring at equinoxes

moon with no regular pattern or orbit

8. solar time

time based on Sun's position

alignment of three celestial bodies in a straight line

line connecting closest and farthest points in orbit

theoretical framework of star development

9. asteroid

small rocky body orbiting the Sun, smaller than planets

photography of celestial objects and phenomena

small, low-mass star, often red or brown

star and orbiting bodies

10. secular motion

time between similar moon phases

slow, continuous movement of celestial objects

maximum speed of electromagnetic waves

abundance of elements heavier than helium

11. ionosphere

angle between rotational axis and orbital plane

study of universe using gamma-ray observations

Earth's atmosphere layer ionized by solar radiation

Sun and orbiting celestial bodies

12. geometric albedo

luminous celestial body made of hot gases

eccentricity of an orbit

reflectivity of a celestial body based on geometry

star with features of different types

13. parallax

reference point for coordinates

apparent shift of nearby objects

universe's initial explosive expansion origin event

degree of stretching or lengthening

14. stellar evolution

changes a star undergoes over time

plane containing the total angular momentum of system

path of a star or galaxy over time

star's energy generated by gravitational contraction

15. tangential velocity

parameters defining an orbit

table listing astronomical object positions over time

speed moving along a circular path

star light reddening caused by dust

16. plane of the sky

rotation aligning with orbital period

sky as seen from Earth

large planet composed mainly of gases

measurement of celestial object positions and motions

17. planetary nebula

point directly above observer on Earth's center

expanding gas around dying star

oscillation of celestial bodies like the Moon

sun's outer atmospheric layer above the photosphere

18. outer space

small rocky body orbiting the Sun, smaller than planets

time for one orbit

closest star at galaxy's center of our solar system

region beyond Earth's atmosphere

19. aphelion

another galaxy designation

point in orbit farthest from the sun or star

dusk or dawn light period

path of a star or galaxy over time

20. obliquity

star with changing brightness

90-degree phase angle between celestial objects

loosely bound star group

axial tilt of a planet or star

Vocabulary Quiz:

1. major axis

2. photosphere

3. planetesimal

4. orbital elements

5. celestial pole

6. total solar eclipse

7. irregular moon

8. solar time

9. asteroid

10. secular motion

11. ionosphere

12. geometric albedo

13. parallax

14. stellar evolution

15. tangential velocity

16. plane of the sky

17. planetary nebula

18. outer space

19. aphelion

20. obliquity

Select vocabulary category you want to browse:

Vocabulary Quiz:

1. major axis

2. photosphere

3. planetesimal

4. orbital elements

5. celestial pole

6. total solar eclipse

7. irregular moon

8. solar time

9. asteroid

10. secular motion

11. ionosphere

12. geometric albedo

13. parallax

14. stellar evolution

15. tangential velocity

16. plane of the sky

17. planetary nebula

18. outer space

19. aphelion

20. obliquity

Select vocabulary category you want to browse:

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