HPS Atsonomy (Unit 9)

Hipparchus

First recorded start maps

Ptolemy

Geocentric model of solar system

Copernicus

First heliocentric model of solar system

Brache

Incredible observations

Kepler

Laws of planetary motion

Galileo

First to utilize the refractive telescope

Newton

First reflective telescope

Hubble

Observed redshifts of galaxies (close or far)

Penzias and Wilson

Discovered CMB (Cosmic Microwave Background)

Hipparchus, Ptolemy, Copernicus, Brache, Kepler, Galileo, Newton, Hubble, and Penzias and Wilson

Order of old white male astronomers

Sextant

Instrument that measures angle of stars

Parallax

Apparent motion of star to observers position

Retrograde Motion

When planets appear to move backwards in the sky compared to stars

Reflector Telescope

Mirror based

Refractor Telescope

Lense based telescope

Spectroscope

Breaks down wavelengths of visible light

Space Probes

Robotic spacecraft sent to explore space (no human)

Declination

Celestial Latitude Coordinates (Northern star = 90 degrees)

Right Ascension

Celestial Longitude Coordinates

Ecliptic

The path the sun takes in the sky (rises in east/sets in west)

Zenith

90 degrees above the observer’s head (north pole = north star)

Altitude

How high the star is above the horizon (one first = 10 degrees)

Azimuth

Direction the star is in (N=0 degrees, S = 180 degrees, etc)

Paths of celestial bodies

Very ovally and not round!

Constellations

Groups of stars which appear close together from Earth to form a recognizable shape

S, M, V, E, M, AB, J, S, U, N, KB, and OC

Order of solar system

Keplers Law

All orbits are ellipticsl, equal time = equal area, year is affected by distance from sun

Semi-major Axis

The distance planets are from the sun

Magnitude

how bright a star appears (related to brightness)

Temperature

Average Kinetic Energy

Brightness

Power per unit area (W/m^2)

Luminocity

Power of a star

Composition of a Star

Hydrogen and Helium

Star Sequence

Nebula, Protostar, Main Sequence Star, Red Giant, Super Red Giants (split after that)

Astronomical Distances (smallest to largest)

Astronomical Unit, Lightyear, Parsec, Megaparsec

Steady State Theory

The universe looked the same the whole time and won’t change with time

Hubble’s Constant

As things are farther away, the larger the shift in the color spectrum and faster they move

Redshift

When a galaxy is far away and appears more red

Cosmic Microwave Background

Leftover micro radiation left over from the big bang

Closed Universe

“Big Crunch” and gravity wins

Flat Universe

“Critical Density” and the universe never dies

Open Universe

“Big Freeze” and gravity loses

Inflationary Universe

“Big Rip” and gravity loses

Critical Density

All the forces in the universe stay the perfect ratio and the universe continues forever