physical universe unit 1 Flashcards
age of our solar system
5 billion years
age of the universe
14 billion years
age of galaxies
10 billion years ago
modern man age
400,000 years
AU
astronomical unit, average distance between the sun and earth. describes distance WITHIN our solar system.
lightyear
distance that light travels in one year. used to measure distances OUT of our solar system.
nebula
large cloud of dust and gas, stars are born from here.
star cluster
a grouping of 10-10,000 stars that are in the same neighborhood
galactic cluster
galaxies appear clustered in groups of 20, our galaxy is part of the LOCAL GROUP
-nearest cluster is the Virgo Cluster
nucleus
positive charged
sidereal day
time it takes for earth to do one 360 degree spin (2h 56 mins)
solar day
time it takes for sun to return to the same E/W position above us. (24 hours)
synodic month
time it takes for moon to complete its phases (29.5 days)
spring equinox
march 21, equal day/night, the equator
fall equinox
sept. 21st, equal day/night, the equator
solar calendar
matches with the sun. our year starts 11 days after the winter solstice.
lunisolar calendar.
add a leap month. each month is a lunar month, so 29.5 days. SO they alternate 29/30 etc. new month = a new moon. to account for the 354 days that this lunisolar calendar creates, we add leap month every 2-3 years to make up for lost time.
kiva layout
wooden roofs above the kiva with an alter and benches
cultural significance of pueblo bonito
at the end of the north road form pueblo bonito, there is a lot of broken pottery. meant to help people in their next lives, left because climate became even worse
aristotle’s view of motion
earth material always returns to earth. everything returns to where it came from. heavier things fall faster than light things.
the universe’s layout according to aristotle
-the planets, moon, and sun all revolve around earth
-earth is geocentric (ptolemy believed this too)
-a celestial sphere surrounds the solar system with holes poked into it. light from the heavens shine through the holes and this is why we see stars
Matter is discrete.Or matter is made up of tiny building blocks called atoms.
democritus
Measured the size of the earth
Eratosthenes
Your senses cannot show your truth; only clear, rational thinking can lead you to truth
plato
Objects fall downward because they are made of earth, and earth wants to return to earth
aristotle
The stars lie in the celestial sphere. They are actually the light from the heavens shining through holes in the fabric of the celestial sphere.a
aristotle