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52 Cards in this Set
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- Back
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What are the parts of an atom Describe the parts How are the parts arranged |
Nucleus – A nucleus has neutrons and protons in it. Neutrons have no charge they are neutral. Protons have a positive charge. Orbitals – This has electrons in the area they are at different distances from the nucleus. Electrons are negative charge. |
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Describe an atom in the ground state Describe an excited atom How are the atom in a gas (such as a star) identified? |
Ground state – and electrons most tightly bound state and lowest permitted energy. Excited atom – energy has been added and the electron has moved to a higher state – can jump up 1, 2, or 3 levels. It cannot stay excited too long it will fall back to ground state and release energy. This allows us to identify elements in a gas using a wavelengths of light sword or emitted from the excited atom. |
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How does heat relate to atom/molecule agitation? Define temperature What is blackbody radiation? |
The hotter the object, the more agitated the Atom/molecules. The heat is the flow of thermal energy. Temperature is the average speed of particles. The intensity of particle agitation. Blackbody radiation – the radiation emitted by a heated object. Objects that glow brightly. At room temperature These perfect emitters and perfect absorbers would look flat, but at higher temps would glow at wavelengths we would see. |
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What color? |
Blue |
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Color? |
Green-blue |
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Color? |
Red-orange |
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Total energy under the curve is proportional to the total _________________ emitted. Hotter objects give off electrons that __________ _________ and more _________ is given off |
Total energy under the curve is proportional to the total energy emitted. Hotter objects give off electrons that travel faster and more energy is given off. |
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What is the relationship tween solar temperature and energy emitted? |
A small temperature difference leads to a large difference in the amount of energy given off. |
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What are three types of spectra and how does it work? |
Three types: 1 Continuous spectrum – no absorption or emission lines. 2 Absorption/dark line spectra – occurs when radiation passes through a cool gas. atoms in the gas absorb photons of certain wavelengths. They are then missing from the spectrum and the position is seen as dark absorption lines. 3 emission or bright line spectra – these are produced as photons are emitted by an excited gas. |
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How does a spectra show? |
The stars have spectra. The light passes outward through the gas is near the surface. |
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What is the spectral classification in order from hot to cool? |
Spectral sequence is determined by the stars mass. (Oh be a fine guy/girl kiss me) O-is the hottest, B, A, F, G, K, and M is the coolest |
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Stellar mass controls what stellar properties? |
1. Stellar mass 2. Surface temperature 3. Absolute magnitude 4. Luminosity or intrinsic brightness 5. Evolutionary stage 6. Core temperature and density 7. Fusion and energy production rate 8. Spectral type (OBAFGKM) 9. Lifetime |
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Describe the Doppler effect? |
The apparent change in the wavelengths of electromagnetic radiation caused by the motion of the source. If a star is moving toward earth, the lines shift towards a shorter wavelength blue. The shift is toward red, the longer wavelength, if it is moving away from earth. These shifts can be seen in the spectrum. |
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Describe stars What must be in balance? |
Stars are great falls of hot gas held together by gravity. The gravity could cause collapse were they not so hot. The hot gas creates a high pressure, that could lead to an explosion, but the gravity will hold it together. Therefore the hot gas pressure and gravity must be in balance. |
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List and describe the parts of the sun. |
1) Core – where nuclear reactions generate energy, hottest area. 2) radiative zone – it is also how energy is carried outward from this layer. 3) convective song – it is also how the flow of energy is in this layer. 4) Photo sphere – visible surface, gives off most of the sunlight we get, appearance is a pattern called granulation. 5)Chromosphere – above the photosphere, very low density, seen during the total eclipse as a pink line, has spicules that are flame like sets of gas. 6) Corona – outer most region and very hot, very dim and low density, can be seen during the solar eclipse, has a magnetic carpet that’s looped magnetic fields through the photosphere. |
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Compare and contrast sunspots, spicules, solar wind, streamers, prominences, filaments, and flares |
1) Sun spots Dash earth size dark blemish on the surface of the sun, it indicates a region of lower temp, has a cycle of 11yrs. 2) spicules – small solar storm that expels jets of hot matter into the suns lower atmosphere. 3) Solar wind – outward flow of fast moving charged particles from the sun. 4)Streamers – decrease convection and prevent surrounding plasma from entering the sun spots. 5) prominences – loop/sheet of glowing gas ejected from an active region on the solar surface into the inner parts of the corona under the influence of the suns magnetic field. 6)Filaments – are forms of prominences is seen from above. 7) flares– explosive events occurring in or near an active region on the sun |
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What causes photosphere granulation? |
By hotter rising centers and the edges are cooler sinking gas |
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Stars of hot temperatures emit what? |
Radiation |
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What is responsible for many of your Sun’s activities? |
Magnetic fields |
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Describe stellar clear fusion What fuses? |
The energy source used by stars. Atomic nuclei are joined. Nuclear fission is the energy source of nuclear power plants here the atom is split. There is a fusion of atomic nuclei. |
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What are the four forces of nature? Describe each. |
1. Gravity– attractive effect that any massive object has on all other massive objects. 2. Electromagnetic force – force electric or magnetic exerted between any two charge particles. 3. Weak force – are involved in radioactive decay of some nuclear particles. 4. Strong force – bind atomic nuclei together. |
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What is the electromagnetic spectrum and what are examples of components? |
Gamma rays, x-rays, infra red light, microwaves, UHF, VHF, FM, AM, radiowaves |
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Are cosmic rays part of the electromagnetic spectrum? |
No |
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What atom has the most tightly bound? What does this mean ? |
Iron No nuclear reaction can begin with iron and release energy |
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What happens on earth when there are few sunspots? |
Cooler temperatures |
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How long is a sunspot cycle |
11 years |
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What does solar wind do to the earth? |
It distorts earths magnetic field, disrupts navigational systems, causes surges in electrical power links, damages earths satellites. |
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How is the distance to a star calculated? |
Triangulation using parallax shifts |
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How far is parsec and what is it? |
The distance to an imaginary star with a parallax of one arc sec. 1pc=2.06x10^5 AU or 3.26 light years. |
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What does earths atmosphere due to observations? |
Blurs and interferes |
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What is stellar proper motion? |
Uses the motion of stars around the galaxy center, this leads to different shapes of constellations |
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Compare and contrast apparent and intrinsic brightness. What determines brightness? |
Apparent brightness of a star is how bright it actually appears to an observer, Intrinsic Brightness or luminosity is the amount of energy the star radiates per second in all directions. Brightness is due to: 1)Amount of light emitted 2) object distance |
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What magnitude of star can be seen with the naked eye? |
6.5/7 is the dimmest visible items |
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What is flux? What is Luminosity? It is affected by what ? |
Flux is the energy in joules per second falling on 1M^2 of the planets surface, luminosity is the total energy the star radiates in one second, it is affected by temp, surface area, and can use the luminosity and temp to determine the stars diameter |
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What is the relationship between magnitude of brightness and luminosity? |
The brightness of a star is proportional to its luminosity divided by its distance from the observer squared |
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What is an HR diagram? |
Organizes stars according to their diameter, separates the effect temp and surface area on luminosity |
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How often does our sun rotate? What stars are on the main sequence? |
Our sun rotates 1 time/month Main sequence: 90% of normal stars |
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Describe the Giants and super Giants. Describe a red dwarf and a white dwarf. |
Are at the top of the HR diagram, 1,000x Our suns diameter Are small and cool, have low luminosity. |
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What is an interferometer? |
Used to determine a stars size and shape |
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Why do large stars have narrow spectral lines? |
Because atoms collide less often |
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List luminosity classification. |
A stars spectrum helps place it on HR diagram, large stores have less dense atmosphere, stellar spectra indicate size: they reveal atmospheric density, luminosity classes: based on stellar size, half of all stars are members of binary system and are visual binary systems, faint stars are the most common type of star, the mass, stars aren’t uniform in density, super giants at the center are dense. |
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What is our Sun’s Spectral type? |
G2V |
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How frequent are binary systems |
More than half of all stars are members |
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What are the most common types of stars? |
Faint stars |
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What is the mass to luminosity ratio for main sequence stars? |
L= M^3.5 |
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What is interstellar medium? Is it hot or cold? What is it made up of? |
The gas and dust between stars. Cold. Hydrogen and helium. The dust is carbon, silicates, iron, ice, and organic compounds |
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Stars are born of what? Dying stars do what? |
Interstellar medium an aging stars return gas and dust back to the interstellar medium. Stars are born in nebula. Return gas and dust back to the interstellar medium |
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What is the most abundant element in the interstellar medium? |
70% hydrogen |
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What is a nebula? |
A cloud of gas and dust |
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List the types of nebula. Describe each. |
1) HII regions - hound of gas ionized by ultraviolet radiation from nearby hot stars (emission nebula) pink color (red+blue+violet) B1 25,000 K or hotter. 2) reflection – occur because nearby stars are not hot enough to ionize hydrogens. Light is scattered by tiny dust specks mixed with gas. They look blue because short wavelengths scatter more easily than long wavelengths. 3)Dark nebula – are dense clouds of gas and dust that obstruct the view of more distant stars. They are visible where dense clouds of gas and dust are silhouetted against background regions filled with stars or bright nebula. |
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What is an HI region? What is an HII region? |
Clouds of gas ionized,HI is neutral hydrogen. Clouds of gas ionize by ultraviolet radiation |
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interstellar medium is made up of cool clouds, intercloud medium, molecule clouds, and coronal gas. Describe each. |
1)cool clouds-give off radio, infrared, ultraviolet or X-ray wavelengths, but no visible light. |
