What are the various types of electromagnetic radiation?
Gamma Rays, X-Rays, Ultraviolet light, visible light, infared radeation, microwaves, and radio waves
What do spectral lines show
Spectral lines identify the elements present and the star's chemical composition
What is the doppler effect used to determine
It is used to determine whether or not a star or other body in space is moving away or towards earth
Electromagnetic spectrum
The arrangment of light waves according to their wavelegnth and frequencies
Photon
Small particles of light that exert force
Spectroscopy
The study of the properties of light that depent on wavelegnth
Continuous Spectrum
An uninterupted band of color
Absorption Spectrum
When visible light is passed through a relativley cool gas under low pressure, where some of teh colors are observed
Emission spectrum
Produced by hot gas under low pressure, series of bright lines of particular wavelegnths. Each element or compond in its gaseous form produces a unique set of spectral lines
Doppler Effect
The perceived change in wavelegnth of a wave taht is emitted from a souce that is moving away or towards an object.
Towards: waves are squished, appearing bluer
Away: waves are stretched, appearing redder
Name the four parts of the sun
The solar interior, the visible surface/photosphere, two atmosphering layers (chromosphere and corona)
Why do sunspots appear dark
They are a lot colder than the surronding solar surface
What are prominences
Promeninces are ionized gases trapped by magnetic fields that extend from regions of intense solar activity, cloudlike
What form of energy do solar flares release
Unltraviolet redio and xray
What happens in nuclear fusion
Elements are fused together. Some energy is released because some matter is converted into energy
Photosphere
Layer that radiates most of the sunlight we see, the "surface"
Chromosphere
Above the photosphere, not visible., produces an emission spectrum reverse of absorption spectrum of photosphere
Corona
The outermost portion of the solar atmosphere, very weak.
Solar Wind
Stream of particles and proton s and electrons taht travel outward through the solar system
Sunspots
Dark regions on the surface of the photosphere
Prominence
Cloudlike structures consisting of chromospheric gases. Ionized gasses trapped by magnetic feilds
Solar flares
breif outbusts of energy at a sunspot clustre releasing unltraviolet radio and xray radiation. Fast moving atomic particles are ejected
What does a prism do
Seperates the visible light into may colors by bending each wavelegnth at a different angle
What color has the longest wavelegnth
Red
Star's spectrum can tell astronomers ..?
the stars chemical composition
Which type of spectrum does the radiation from most stars produce
Emission spectrum
What does the use of doppler effect tell astronomeers about a star
Whether a star is moving away or towards Eart
What spectrum does an incandescent lightbulb producse
Continuous spctrum
What happens at the core of the star
Nuclear fusion
Streams of electrons and protons that shoot out from the sun's corona are the solar....?
wind
Sunspots appear darker on the sun's surfaace because
They are coler than the rest of teh surface
What is the effect of solar flares on earth
Creates auoras
When the sun produces energy, it consoumes hydrogen and produces
Helium
The sun can countinue to exist in its present stable state for another
5.5 billion years
why is an understanding of light importatnt to astronomers
Almost everything we know about the univesre is about light
The arrangment of electromagnetic waves is called the
spectroscopy
THe nature of light
Particles and waves
Particle of lights are called
photons
how are frequency and wavelegnth related
shorter wave higher frequency
Electromagnetic radiation travels at the speed of
light
WHo was the first astronomer to have used telescopes for asttronomical obsercations
Galeleo
The grainy appearance of the sun's surface is due to moving columns of gas called
granuales
the halo like area around the sun's disk that is visible during a solar eclipse is the
corona
ENergy is transmetted inside the sun through
Convection and radiation
The sun's atmospher consists of the corona and the
chromosphere
The number of sunspots increases and decreases in a cycle of
11 years
The sun's energy is created in the area in and around its
core
Spectroscopy is the study of the properties of light taht depend on
waveleghnth
When a wave source ismoving toward or away from an object, the wavelegnth changes, a phenomenon knowh as the
doppler effect
HOw do astronomers determine whether stars are moving towards or wau from earth
Doppler Effect/REd-blue shift
What is nuclear fusion
Nuclear fusion powers stars. It is a process where a nuclear reaction joins two or more nucleus to form one heavier one
What happens when a sound source approaches an observer
The pitch becomes higher
What is the doppler effect and how is it used
The doppler effect is the change in wavelegnth of a wave as it moves towards or away from an object. Away: longer. Closer: shorter. It is used to see if objects in space/stellular bodies are moving to or away from Earth.
What are the parts of the sun and where are they located
Guts
Core
Radiation Zone
ExtiriorConvection Zone
Photosphere
AtmosphereChromosphere
Corona
True or false? Different parts of teh sun rotate at different speeds
True
During nuclear fusion, what is converted into energy
Matter
In what form is most of the energy from nuclear fusion released?
Photons
How did the sun get hot enough to start nuclear fusion
As gas got compressed, the temputare rose.
What does color tell us about a star
Color tells us how hot a star is
What can binary stars be used for
Determining stellar mass
What are parrallax angles
Angle that measures the distance the star has moved
What factors control the apparent brightness of a star
Size, Heat, disatnce
What does a Hertzsprung-Russell DIagram show
The relationshop between the absolute magnitude and temperature of stars
Constellation
patterns of stars
Binary Stars
Stars pulled towards each other by gravety. Use to determine other star's mass. More than 50% of stars in the universe may occour in pairs or multiples
Light-Year
The distance light travels in one year: 9.5 trillion km
Apparent Magnitude
A star's brightness as it appears from Earth
Absolute Magnitude
The absolute brightness of a star, determined by measuring brightness from 32.6 light years away.
Main-Sequence Star
The most common group of stars, a band that runs from upper left to lower right on the diagram
Red Giant
very bright, and large stars. Top right of diagram
SuperGiant
Super large red giants, top center right of diagram
Cepheid Variables
Stars that fluctuate in brightness, get brighter and fantern in a regular pattern. Light Period.
Nova
The sudden brightening of a star, when the outer layer of a star is ejected at a high speed
Nebulae
Clouds of dust and gases in teh vacum of stars. Emission nebulae consist of hydrogen and absorb ultraviolet radiation. UV-> Visible
Reflection nebulae reflect other stars. Composted of dence clouds of large particles called intersteallar dust
How is a star born
A star is born when the core of a protostar reaches at leat 10 million K, starting nuclear fusion
Protostar
A developing star not hot enough to start nuclear fusion
Supernova
The end of life of a huge star, an explosion, millions times brighet than at prenova
White Dwarf
Remains of low mass and medium mass stars. Extremley small, but very very high densities
Neutron Stars
The remains of supernovas, electrons are forced to combined with protons to produce nuetrons. Super dense, pea sized: 100 million tons
Pulsar
A small dying star that radiates short bursts or pulses of radio energy
Black Hole
Remains of suupernova, smailler than neutron stars, very dense with super high gravity, denser than neutron star, nothing, not even light can escape.
THe mass of a star can by determined by studying...?
Binary star systems
What color will a star be with a surface temperature of 5000-6000K
Yellow
Are paralax angles larger smaller if the star is closer to us
Paralax anglesare larger when the star is closer to us
How far is a light year
9.5 trillion kilometers
Is age a factor in apparent brightness
No
Star a is farther away from Earth than star b. Both stars have the same absolute magnitude. Which star will have a larger apparent magnitude?
Star A will have a greater magnitude, it is not as bright from our view, and thus, has a higher magnitude
What relationship does a Hertzsprung-Russell diagram show?
The relationship of temperature and absoulte magnitude/brightness
What percent of stars are main sequence stars?
90%
Before a star is born, the matter that will become the star exists as what
Cool, dark nebula
A star is thought to be born when
A protostar reaches a high enough temperature for nuclear fusion
Into which life cycle stage will the sun enter next
Red giant phase
All stars, regardless of their size, eventually
Run out of fuel and collapse
What remains after a low mass or medium mass stars dies?
A white dwarf
How many light years thick is the Milky way at it's nucleus
10, 000 light years thick
According to the information recieved from radio telescopes, where is our sun positioned in the milky way?
Within one of the spirals
About 60% of all galaxies are of what type
Elliptical Galaxies
Sciencientists know the universe is expanding because of the
Red shift of distant galaxies
According the big bang theroy, the entire universe began as a
Hot, dense, supermassive ball
What is evidence of the big BANG?
Cosmic background raditaions
What are the three properties of stars
Mass, tempature, distance from earth
True or false? A star's color can tell you what it's approximate tempature is.
True
What can binary stars be used for?
Binary stars can be used to determine the mass of a star.
What is the apparent change in position of a star when seen from the oppisite sides of Earth's orbit called?
Parallax Angles
How many stars have parallax angles measured?
Only a few thousand stars are known with certainty.
What are reflection nebulae made of?
Dense clouds of interstellar dust.
In a red giant, what two things are used to produce energy?
Hydrogen and gravitational energy.
What kind of galaxy is the milky way
A spiral galaxy.
What differ galaxies?
Shape, Size, and Age of their stars.
What is the life cycle of low mass stars?
Nebula -> Protostar -> Main sequence -> White dwarf -> Black dwarf
What is the life cycle of a medium mass star?
Nebula -> Protostar -> Main sequcne -> Red giant -> Planetary nebula -> White Dwarf -> Black dwarf
What is a planetary nebula
A planetary nebula are clouds of gases from the outer layers of former medium mass red giant
What is the life cycle of massive stars?
Nebula -> Protostar -> Main sequence -> SuperGiant -> SuperNova -> Neutron star or Black whore
What is the aproximate absolute magintude and surface tempature of a protostar
4000k, Magnitude 0
What is the absouleet magnitude and surface tempature of a giont star
4500 K, Mag -8
What is the absolute magnitude and surface temperature of the planetary nebula?
15,000K, Mag 8
How do we study black holes
They find evidence of matter dissapearing into apparent nothingness.
How can a Hertzspring-Russell diagram be used to show the evolution of a star?
It can shoow the various phses in the evolution of a star.
What phases has the sun gone through?
The sun has gone from dust and gases, into a protostar, and then into a main-sequence star.
