ch 6-1 an inventory of the solar system

what did early astronomer know?

• moon, stars, mercury, venus, mars, jupiter, saturn, comets, and meteors

what does the solar system have?

• 1 star

• 8 planets with 292 moons

• 7 large asteroids (>200km)

• 5 dwarf planets with 8 moons

• more and 100 Kuiper belt objects more than 300km in diameter

• millions of smaller asteroids, comets, and meteoroids

how many planets are in the solar system and how many moons do they have?

• 8 planets and 292 moons

how many dwarf planets are in the solar system and how many moons do they have?

• 5 dwarf planets with 8 moons

what are meteoroids?

• rick and metals that range in size from grain of sand to 1 m in diameter

what are asteroids?

• rock and metals that range in size from 1 m to hundreds of km

what are comets?

• celestial objects made mostly of ice, dust, and rocky materials

• often described as ‘dirty snowballs’

as of Jan 15 2026, how many extrasolar planets have been confirmed across 4532 planetary systems?

• 6080 extrasolar planets

what does understanding planetary formation in our own solar system help us understand?

• the formation of these extrasolar systems