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Horizon's Exploring Universe
Chapters 5-9
69
Astronomy
Undergraduate 1
07/23/2008

Additional Astronomy Flashcards

 


 

Cards

Term
Electromagnetic Radiation
Definition
Changing electric and magnetic fields that travel through space and transfer energy from one place to another.
Term
Wavelength
Definition
The distance between successive peaks or troughs of a wave.
Term
Photon
Definition
a particle of light
Term
nanometer
Definition
nm unit of distance equaling one-billionth of a meter 10-9 meter
Term
Limits of human vision in terms of wavelength
Definition
400nm-700nm
Term
Wavelenght where the human eye is most sensative
Definition
555nm-green
Term
Photopic vision mode
Definition

Day vision with good lighting conditions

cones are used 

Term
Mesotopic vision mode
Definition

tansition vision between light and dark lighting

rods and cones are used 

Term
scotopic vision mode
Definition

night vision dark lighting

rods only used 

Term
Seeing
Definition

atmospheric conditions-how steady the air is

provides detail to vision 

Term
Transparency
Definition
how clear the skies are at a given time provides the sight of fainter things in the sky
Term
Reflector
Definition
a parabolic mirror in a telescope
Term
Reflactor
Definition
a lense in a telescope
Term
Aperature
Definition

how big the lense or mirror is in a telescope

bigger is better 

Term
Resolving power
Definition
Ability of a telescope to see more detail
Term
Magnification
Definition

Ability of a telescope to make something seem larger

least important variable of a telescope 

Term
Radio Telescope
Definition

used to detect radio waves

made up of a dish, antenna, amplifier, and computer 

Term
Interferometry
Definition
taking multiple telescopes to make a much the much higher resolution a large telescope would have
Term
Emission Spectra
Definition
Black with bright emission lines
Term
Continuous Spectra
Definition
Emits black body radiation and is composed of the complete specturm
Term
Absorbtion spectra
Definition
Contains entire spectrum with dark lines
Term
Spectral lines
Definition
a line in a spectrum at a specific wavelenght produced by the absorption or emission of light by certain atoms
Term
Atom
Definition
is a model of the proton, nuetron and electon of a molecule
Term
Ion
Definition
An atom that has lost or gained one electron
Term
Isotope  
Definition
same element with a different number of nuetrons
Term
Molecule
Definition
Two or more atoms bonded together
Term
Excited atom
Definition
when an atom goes to a higher energy level or when atoms collide or absorb a proton
Term
Energy level
Definition
the binding energy state of an electron
Term
Ground State  
Definition
The lowest permitted energy level of an electron in an atom
Term
Two ways an atom can become excited
Definition

When Atoms collide

When atoms absorb a photon 

Term
Rods
Definition

Allow the sight of faint light

120 million 

Term
Cones
Definition

Allow the sight of color

RBG

6-7 million 

Term
Averted Vision
Definition
looking out of a corner of your eye to see more
Term
Weins Law
Definition
The higher the temperature the shorter the wavelength or peak intensity
Term
Stefan-Boltzman Law
Definition
As the temperature goes up emitted energy goes up
Term
Doppler Effect
Definition
Frequency increases coming closer making the wavelength shorter and visa versa
Term
Temperature of the Sun's surface
Definition
5800K
Term
Sunspots
Definition
Relativly dark spots on the sun that contain intense magnetic fields
Term
Convection
Definition
To the sun heating and cooling of gases
Term
Granulation
Definition
The fine structure of bright grains coveringt he suns surface
Term
Photosphere
Definition

The birght visible surface of the sun

500 km deep 

Term
Chromosphere
Definition
Bright gases just above the photosphere of the sun
Term
Corona
Definition
Outer atmosphere of the sun
Term
Solar Winds
Definition
Rapidly moving atomss and ions that escape from the solar corona and blow outward through the solar system
Term
Nuclear fusion in the sun
Definition
Atomic nulei running into each other to make heavier elements
Term
Proton-proton chain
Definition
A series of three nuclear reactions that builds a helium atom by adding together protons. The main energy source is the sun.
Term
Differential Rotation
Definition
the rotation of a body in wich different parts of the body have different periods of rotation, like the sun
Term
parallax
Definition
The apparent change in the position of a object due to a change in the location of the observer. This allows us to mesaure the distance of stars
Term
Intrinsic brightness
Definition
The true amount of energy given off by a star in a given amount of time
Term
Luminosity
Definition
the total amount of energy a star radiates in one second
Term
Binary Star
Definition
Pairs of stars that orbit around their common center of mass. Gravitationally bound
Term
Double Star
Definition
When you can see two stars next to each other
Term
Spectroscopic Binary Star
Definition
Binary stars that can only be proven so by a spectroscopic analysis
Term
Eclipsing Binary Variable Star
Definition
A binary star system in which the stars eclipse each other
Term
Mass Luminosity Relationship
Definition
The more massive a star is the more luminous it is
Term
Interstellar medium
Definition
Gas and dust found between stars
Term
Emission Nebula
Definition
A cloud of glowing gas excited by ultraviolet radiation from hot stars
Term
Reflection Nebula
Definition
A nebula produced by starlight reflecting off dust particals in the interstellar medium
Term
Dark Nebula
Definition
A cloud of gas and dust seen silhoueeted against a brighter nebula
Term
Interstellar Reddening
Definition
The process in which dust scatters blue light out of starlight and makes the stars look redder
Term
Shockwave and three causes
Definition
A sudden charge in pressure that travels as an intense sound wave
Term
Star Clusters
Definition
A group of stars that formed together and orbit a common center of mass
Term
Association
Definition
A group of stars not gravitationally bound into clusters
Term
Protostar
Definition
A collapsing cloud of dust and gas destined to become a star
Term
Pressure temperature thermostat
Definition
When a star produces too much energy and expands to cool the center then contracts again to warm
Term
Conevection (energy)
Definition

The transfer of heat by the movement of a fluid 

Term
Conduction
Definition

Heat transfer in the form of energy being transferred from molecule to molecule within the object 

Term
Radiation  
Definition

The transfer of energy (heat) via electromagnectic radiation 

Term
Lifetime of a star
Definition

Stars with larger masses die quicker

Stars with smaller masses die slower 

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