Science 9-Unit E

Solstice

Represents the longest and shortest periods of daylight

Summer solstice:June 21

Winter solstice:December 21

Equinox

represents periods of equal day

Vernal Equinox:March 21st

Autumnal Equinox:September 22st

Planetary Motion

Geocentric model:Aristoles Model(Pythagoras and Euclid)Earth was at Centre

Heliocentric model:Copernicus model,(Galileo and Kepler) sun at centre, Brahe added ellipses, which basically is the way planets orbit.

Ellipses:Planet orbits the sun in an elliptical, oval, motion around the sun.

Telescope

Allows us to see details in our neighbouring planets, and discover new ones. Also to see whats beyond our earth

Astronomical Unit(AU)

Measures local distance in our solar system, uses the distance between centre of sun to centre of earth or 149,599,000km

Lightyear

Measures distances between galaxies, uses the distance light travels in one year, or 9.5 trillion km

Asterisms

Grouping of stars, but not an official recognized as a constellation

ex:big dipper is apart of ursa major

Galaxies

Grouping of dust, stars, and gas held together by gravity, 3 types

-Spiral(our galaxy milky way, is a spiral galaxy)

-elliptical

-irregular

Sun

Centre of solar system, surface is 5000 degrees, and centre is 15,000,000 degrees. A million earths could fit into sun

Asteroids

Orbits in narrow belt between jupiter and mars, scientists dont know where they come from

comets

known as dirty snowballs, made up of dust and ice, and when ice melts it creates trail

meteoroids, meteors, meteorites

Meteoroids, traveling in space, outside of earth’s atmosphere, meteors aka known as shooting stars entered earth's atmosphere but hasn’t hit ground, meteorites hit ground.

Azimuth

compass direction, north is 0 degrees, east is 90 degrees, south is 180 degrees, and west is 270 degrees

altitude

how how in the sky 0-90 degrees

zenith

highest point overhead

Microgravity

Condition where forces acted on mass is greatly reduced, bones have less pressure causing them to expand, heart doesn’t need to pump as hard to regulate blood, muscles get weaken, and visual depth is effected.

What is triangulation used for?

Used to measure the distance to a object far away

What does a spectrometer measure and analyze?

composition of a star

Reflecting vs Reflector mirror

Reflecting vs Reflector Mirror

Reflecting mirrors reflect light at an angle equal to the angle of incidence. Reflector mirrors, on the other hand, reflect light back along the same path. Refractors are better for seeing far away

Where is the Hubble space telescope located?

The Hubble Space Telescope is located in low Earth orbit, above the Earth's surface.