geocentric
a model of the universe in which earth is at the center of the revolving planets and stars.(p73)
kuiper belt
a doughnut-shaped region that streches from around Pluto's orbit to about 100 times Earth's distance from the sun (p105)
heliocentric
a model of the solar system in which Earth and the other planets resolve around the sun (p74)
meteor
a streak of light in the sky produced by the burning of a meteroid in Earth's atmosphere (p107)
ellipse
an oval shape, which may be elongated or nearly circular; the shape of the planets orbits (p75)
asteroid
rocky objects revolving around the sun that are too small and numerous to be considered planets (p106)
nuclear fusion
the process by which hydrogen atoms join together in the sun's core to form helium (p79)
comet
a loose collection of ice, dust and small rocky particles, orbit (p105)
terrestrial planets
the name often given to the four inner planets. Mercury, Venus, Earth, and Mars. (p84)
gas giant
the name often given to the first four outer planets: Jupiter, Saturn, Uranus and Neptune (p95)
2 discoveries Galileo made proving heliocentricity
-jupiter's moons revolved around jupiter not earth
-venus was going through phases like our moon
planets in order
Mercury, venus, earth, mars, jupiter, saturn, uranus, neptune
3 parts of the sun's atmosphere
-photosphere
-chromosphere
-corona
3 things that the inner planets have in common
-small
-dense
-rocky surface
BCR
We live in a heliocentric system, Heliocentric means that the planets revolve around the sun, although Geocentric means that the planets revolve around earth. Copernicus worked out the arrangement of the known planets and how they moved around the sun. Ga