Astro final

• Star System : is a star ( or stars) and any object or plants that orbit around it

• Star : Is a large sphere of gas that generates heat and light through nuclear fusion in its core

• Planet : A spherical thing that orbit a star and has clear its orbit of smaller objects

• Dwarf Planet : basically like a planet but hasn't cleared its orbit.

• Moons/Satellites : objects the orbit a planet

• Asteroid : a small rocky object that orbits a star

• Comet : small icy object that orbits a star

• Galaxy : a large collection of millions and billions of stars all orbiting the same center of gravity

• Cluster : group of galaxies

• Galaxy Cluster : is a collection of tens of thousand of galaxies all held together by gravity

• Galaxy Supercluster : is a large collection of tens of thousands of galaxy clusters held together by gravity

• The Universe : is everything that ever was, is, or will be

• Astronomical Unit (AU) : the average distance between the earth and the sun, 149,600,000

• Light Pollution : is scattered, manmade light which outshines dim light from celestial objects

• Asterism : is a pattern formed from brings stars

• Constellation : region of the night sky; every star inside the boundaries belong to the constellation; there are 88 constellation

• The Celestial Sphere : is the imaginary bubble surrounding the earth on which all celestial objects appear

• Ecliptic : is the apparent path of the sun around earth

• The Celestial Equator : the midway b/w the horizon and overhead point in the celestial sphere

• Altitude : is the degree above the horizon

• Direction : is the location in regards to north south east or west

• Zenith : is the point directly above the observer at an altitude of 90 degree

• North Celestial Pole : the path earth rotates around

• Circumpolar Star : stars that are always visible in the sky; they never set

• Right Ascension : Measure degrees east to west of the vernal equinox

• Declination : measures degrees north to south of the celestial equator

• Vernal Equinox : is the point where the path of the sun crosses the celestial equator

• Arcminute : is 1/60th of a degree on the sky

• Arcsecond : is 1/60th of an arcminute

• Solstice : when earth is tilted directly towards or away from the sun

• Equinox : hallway b/w solstices when the earth switches from pointing away to pointing towards the sun

• Speed : how far in a certain amount of time

• Velocity : both the speed and the direction

• Acceleration : change in velocity

• Vacuum Chamber : a chamber where there is no air resistance or friction

• Mass : how much stuff makes up an object

• Weight : the force of gravity pulling on an object

• Momentum : mass times velocity

• Net Force :overall force acting on an object

• Newton’s Second Law of Motion : f=ma

• Momentum : can be exchanged b/w objects but the total amount stays the same

• Angular momentum : can be exchanged b/w objects , but the total amount stays the same if there are no net torques

• Semimajor Axis half the longest length of an ellipse or major axis

• Perihelion : point in a planet's orbit that is closest to the sun

• Aphelion : point in a planet's orbit that is furthest from the sun

• Eccentricity : how squashed the elliptical orbit is, closer to 1 is unbound, closer to 0 is circle

• The Geocentric Model : earth centered model

• Model : is a conceptual representation

• Theory : is a testable explanation for many observations and experiments

• Retrograde Motion : earth is faster than mars in the orbit, when passing mars, it appears to slow down, move backwards then forward

• Epicycles : are circles on circles, the movement in a solar system

• Heliocentric Model : sun centered solar system, but not the center of the universe

• Astronomy : actual science

• Astrology speculation

• Photons : particles of light

• How are wavelength and frequency related? : inversely, wavelength goes up, frequency goes down

• Difference between reflect and refract? : reflecting is the bouncing off

Refracting is passing through

• Particle-wave duality of light : light behaves both as particle and a wave simultaneously

• Lens : curved material that refracts and focuses light

• CCDs : Sensitive detectors od photons

• Angular Resolution : measure of the sharpness and clarity of an image

• Spectrograph : disperses light and records it on a detector

• Spectral Resolution : the sharpness of detail that can be seen in a spectrum

• Light curve :a plot of brightness versus time

• Seeing : a measure of celestial objects blurring due to the atmosphere

• Adaptive optics : corrects the scrambles of incoming light waves

• Spring Tide : moon closest to the earth's orbit in alignment with the sun

• Neap Tide : moon closest to the earth's orbit but not in alignment with the sun

• Tidally locked : the time it takes for the moon to complete 1 full orbit around the earth is = the time it takes for the moon to rotate around itself

• Lunar eclipse : Moon passes into earth's shadow

• Umbra : full shadow

• Penumbra : partial shadow

• Solar Eclipse : moons casts a shadow onto the earth

• Seismology : is the study of seismic waves and how they change to learn about the earth's interior

• Mantle : medium density rock

• Crust : low density rock

• Lithosphere : solid lawyer of rock

• Conduction : heat flows from warm areas to cold areas

• Radiation : heat is released as light

• Erosion : gradual breakdown or transport of rock

• Scarp : crack caused by settling as a worm planetary body cools

• Regolith : fine powder of pulverized rock covering the moon's surface

• Subduction Zone : dense seafloor crust is shoved under lighter continental crust and recycled

• Ridge : seafloor spending pulls apart the crust , allowing material to rise up and cool to form new crust

• Hot spot : plume of hot mantle material

• Great Red Spot : located in Jupiter

• Orbital Resonance : recurring gravitational interaction usually due to orbits related by a ratio

• Shepherd Moons : a pair of moons that keep a ringlet sharp and narrow

• Nebular Theory : solar system is formed in a collapsing gas cloud

• Nebula : region of gas and dust

• Solar Nebula : region of gas and dust out of which the solar system formed

• Planetesimals : planet pieces

• Protoplanetary Disk : partially collapsed region of gas forming a stellar system

• Hydrostatic Equilibrium : the balance of the tow Maine forces of the sun, outward force of radiation, inward force of gravity

• Layers of the Sun (order of them, not specifics)

• Core : energy generated by photons buy fusing hydrogen atoms into helium

• The Radiation Zone : region where energy is transported by the radiative force of photons from the core

• The Convection Zone : region where energy is transported upward by convection

• The Photosphere : the visible surface of the sun

• The Chromosphere : beginning of the sun's atmosphere

• The Corona : outermost layer of the sun's atmosphere

• The Solar Wind : a flow of charged particle from the surface of the sun

• Convection is the process in which cool water sinks down and collects more heat to convert into hot water and then repeat the process

• Fusion : nuclei combine to form a new atom

• Fission : the splitting of nuclei into smaller atoms

• Sunspots : are cooler areas on the sun's surface

• Magnetic Field : a field generated by the movement charged particles that also influences other charged particles

• Solar Flares : are outbursts of x rays and charged particles generated by the sun's magnetic activity

• Solar Prominences : are bands of trapped gas in magnetic field lines anchored to the sun's surface

• CMEs : are huge releases of plasma and charged particles from the sun’s corona

• Asteroids : small rocky objects floating in space

• Comets : small icy objects floating in space

• Hydrogen : is the simplest atom to make, which means its most abundant element in the universe

• Helium : is the second simplest atom to make

• Protons : are particles with positive charges

• Electrons : are particles with negative charges

• Ground State : n = 1, as it requires the least amount of energy to live in

• Excited State : If an electron jumps up an energy level, it is called an

• Spectroscopy : is the science that studies the spectra formed from splitting light from a source into its individual 's

• Spectrum : counts the number of photons at each λ

• Flux : is a measure of the total amount of photons

• Continuous Spectrum : is produced by photons emitted at all wavelengths

• Absorption Spectrum : is produced when another object absorbs continuous light at a certain wavelength

• Emission Spectrum : is light emitted from an object that does not generate its own light, but was heated by something else

• Absorption line : is a decrease in counted photons at a specific λ due to getting absorbed by one or more atoms

• Emission line : is an increase in counted photons at a specific due to getting emitted by one or more atoms

• Redshift : As something is emitting light moves away, the λ’s stretch out. Longer λ = redder color

• Blueshift : As something is emitting light moves towards you, the λ’s compress. shorter λ = blue color

• Red Giant : ▸ H is used up in the core -> it’s all fused to He, As the He core contacts (no fusion in the core now), H starts fusing to He in a shell around the core, Shell fusion increases -> L increases -> star expands from so much radiation pressure, becomes a red giant

• Helium Flash : the rapid increase of He fusion in a He core

• Thermal Pulses : periodic spikes in fusion rate in the shells

• Planetary Nebula : where Double-shell fusion ends with a pulse that ejects the outer layers of the star

• White Dwarf : an extremely dense leftover core of a low-mass star help up by the force of electrons

• Chandrasekhar limit : A white dwarf cannot be more massive than 1.4 times the Sun’s mass

• Nova : sudden H to He Fusion, explosion, white dwarf left intact

• White Dwarf Supernova : fusion on the surface combined with hitting the Chandrasekhar limit causes total explosion, no remnant

• Supernova : the explosion of the outer layers of a massive star

• Neutron Star : If the core is less than ~3 times the Sun's mass, the force of neutrons is enough to hold the core up from gravity

• Pulsar : a neutron star that emits beams of radiation along the axis of its magnetic field