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Download test 1 | GEMS 206 - The Night Sky and more Quizzes Mathematics in PDF only on Docsity!
equinoxes what when
when the sun shines equally on both
hemispheresspring/vernal march 21fall/autumnal sept 22
TERM 2
ecliptic plane desc
DEFINITION 2
The apparent path of the Sun's motion on thecelestial sphereas
seen from Earth is called the ecliptic. Theecliptic planeis tilted 23.
with respect to the plane of the celestial equator since the Earth's
spin axis is tilted 23.5 with respect to its orbit around the sun. The
ecliptic plane intersects the celestial equatorial plane along the
line between theequinoxes.
TERM 3
solstices what when
DEFINITION 3
longest and shortest days of the yearsummer:
northernhemisphereis tipped most directlytowardthe sun
june 21winter solstice: shortest day the
southernhemisphereis tipped most directly towards the sun
TERM 4
seasons why
DEFINITION 4
caused by the 23.5 degree tilt of the earths axismore direct
sunlight equals warmer
TERM 5
solar days and sidereal days define and
diff
DEFINITION 5
the time it takes for the sun to appear in the same place in
the skythe time it takes
meridian
imaginary half circle stretching from horizons to zenith
TERM 7
zenith
DEFINITION 7
the point directly overhead straight up 90 degrees
TERM 8
horizon
DEFINITION 8
boundary between earth and sky
TERM 9
why winter and summer constellations
DEFINITION 9
because of the suns orbit we only see the ones away from
the sun
TERM 10
circumpolar
DEFINITION 10
never set because near the north pole
light year
time it takes for light to cross the solar system/dist light
travels in a year 9.46 trill km
TERM 17
parsec
DEFINITION 17
3.62 ly, comes from parallax
TERM 18
nearest star other that
sun
DEFINITION 18
proximus centari
TERM 19
what are angular sizes?
DEFINITION 19
a measure of the angle formed by extending imaginary lines
outward from our eyes to span an object
TERM 20
how many galaxies are there in our universe?
DEFINITION 20
100 billion
How many stars are there in our universe?
10^
TERM 22
milky way
DEFINITION 22
spiral galaxy we are a part of
TERM 23
local clusters
DEFINITION 23
40 in a group of galaxies
TERM 24
virgo cluster
DEFINITION 24
The Virgo Cluster is a cluster of galaxies whose center is 53.
0.3 Mly (16.5 0.1 Mpc)
TERM 25
how old and big is the universe?
DEFINITION 25
13.8 billion
greek model, plato, aristotle, ptolemy
geocentric, the universe revolves around earth
TERM 32
copernicus
DEFINITION 32
died in 1543 and publishes work and paves the way for the
heliocentric model of the universe
TERM 33
tycho
DEFINITION 33
did naked eye observations of planetary positions
TERM 34
kepler
DEFINITION 34
hired by tychoabandoned the idea of perfectly circularlaws of
planetary motion eliptic
TERM 35
galileo
DEFINITION 35
saw sun spots he saw as imperfectvenus goes through
phases orbit sun not earth1633 ordered to recant
heliocentric model
things reHeliocentrism, or heliocentricism, is the
astronomical model in which the Earth and planets revolve
around a stationary Sun at the center of the Solar System.
TERM 37
geocentric model
DEFINITION 37
In astronomy, the geocentric model, is a description of the
cosmos where Earth is at the orbital center of all celestial
bodies.
TERM 38
scientific method
DEFINITION 38
The scientific method is a body of techniques for
investigating phenomena, acquiring new knowledge, or
correcting and integrating previous knowledge. we can prove
things false never true
TERM 39
nebular theory
DEFINITION 39
In cosmogony, the nebular hypothesis is the most widely
accepted model explaining the formation and evolution of the
Solar System.
TERM 40
key elements of the solar system
DEFINITION 40
hydrogen and helium
oort cloud
The Oort cloud , or pik-Oort cloud, is a hypothesized spherical
cloud of predominantly icy planetesimals that may lie roughly
50,000 AU, or nearly a light-year, from the Sun.
TERM 47
circularization, disk, angular momentum
DEFINITION 47
temp of nebula increases as it collapses into a disk as
collisions happen an it shrinks due to angular momentum
TERM 48
age of the solar system
DEFINITION 48
4.5 billion years
TERM 49
size of solar system from one end to the other
DEFINITION 49
AU 40light time 4.3 ly
TERM 50
formation of the moon
DEFINITION 50
result of a collision between earth and a planetoid
winter hexagon
Sirius - Canis MajorProcyon - Canis MinorCapella -
AurigaAldeberan - TaurusRigel - Orion
TERM 52
pollux and castor
DEFINITION 52
Pollux - GeminiCastor - Gemini (this star is sextuple star
system!)winter hexagon
TERM 53
Ursa Minor
DEFINITION 53
is important because it is the Pole Star (find it from the
"pointer" stars Dubhe and Merak in the Big Dipper)
TERM 54
Betelgeuse
DEFINITION 54
orion
TERM 55
regulus
DEFINITION 55
leo
Sirius
- Canis Major
TERM 62
Capella
DEFINITION 62
Auriga
TERM 63
Alberan
DEFINITION 63
Taurus
TERM 64
Rigel
DEFINITION 64
Orion
