.4
.7
0, 3, 6, 12, 24, 48, 96, 192, 384
1
1 g/cm3
1. planets revolve around the sun in elliptical orbits 2.laws of
1.3
1.6
10
11 billion years old
15 million c
19.6
25
25 days
3 x 10^8
38.8
5
5 billion years old
5.2
6 pm, 6 am, 12 am
6,000 k
a piece of earth that fell off, a captured asteroid, accretion-
aristotle, copernicus
blue
carbon dioxide
carbon dioxide
detect the age of the oldest objects and stars, detect the rate
distant fixed
earth, sun
elliptical, spiral, barred
false
galxies recede from us in all directions and more distant ones r
hydrogen & helium
improved telescope, mapped earth's moons, observed jupiter's moo
mare or maria
mars
nitrogen
nuclear fusion
nuclear fusion, hans bethe
photosphere
retrograde
spectrum
starry messenger / sidereus nuncius
supernovae, parallax, stars whose absolute light output can be m
true
tycho brahe
v= ho*d
v=z*c