Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
164 Cards in this Set
- Front
- Back
|
To analyze light in detail, we need to spread the light out according to wavelength into a?
|
Spectrum
|
|
|
What is used to spread light out into a spectrum?
|
A spectrograph
|
|
|
Most modern spectrographs use a grating in place of a?
|
Prism
|
|
|
This is a piece of glass with thousands of microscopic parallel lines scribed onto its surface?
|
Grating
|
|
|
What are the three kinds of spectra?
|
1. Continuous
2. Absorption 3. Emission |
|
|
The spectrum of this spans all visible wavelengths, without interruption?
|
Commin (incandescent) light bulb
|
|
|
What are some examples of things that emit a continuous spectrum?
|
1. Really hot fire pokers
2. US 3. Incandescent Bulb 4. Cats |
|
|
Objects that emit a continuous spectrum are giving off this?
|
Blackbody Radiation
|
|
|
Wein's law states that the hotter an object is, the wavelength of its peak output is?
|
Shorter
|
|
|
273.15 plus degrees celsius equals?
|
Degrees Kelvin (K)
|
|
|
The Stefan-Boltzmann Law states that hotter objects emit more energy than?
|
Cooler objects of the same size.
|
|
|
The area under the blackbody curve equals?
|
Energy
|
|
|
Which is hottest?
a. A blue star b. a red star c. A planet that emits only infrared light |
A blue star
|
|
|
The number of protons in the nucleus equals?
|
Atomic Number
|
|
|
The number of protons plus neutrons equals?:
|
Atomic mass number
|
|
|
These consist of two or more atoms (H2O, CO2)?
|
Molecules
|
|
|
Physicists commonly refer to these as energy levels?
|
Electron Orbits
|
|
|
Photons at a specific energy/wavelength can cause this to move to a higher energy state?
|
An electron
|
|
|
The electron prefers to be where?
|
At the lowest energy state.
|
|
|
A thin or low-density cloud of gas emits light only at specific wavelengths that depend on its composition and temperature, producing a spectrum with this?
|
Bright Emission Lines
|
|
|
A cloud of gas b/w us and a light bulb can absorb light of specific wavelengths, leaving this in the spectrum?
|
Dark Absorption Lines
|
|
|
What is an example of something that emits an absorption line spectrum?
|
The Sun
|
|
|
Each type of atom or ion has a unique set of energy levels, thus, each type absorbs and emits photons with this?
|
A unique set of wavelengths.
|
|
|
Each of these correspond to a unique photon energy, frequency, and wavelength?
|
Transition
|
|
|
Each type of atom has this?
|
A Unique Spectral Fingerprint
|
|
|
Observing the fingerprints in a spectrum tells us this?
|
What kinds of atoms are present
|
|
|
All stars produce this?
|
Dark Line Absorption Spectra
|
|
|
Why are there no green (or purple) stars?
|
1. The blackbody curve of the sun
2. The way our eye works |
|
|
The wavelength which is the location of the PEAK of the black body curve tells us what about a star?
A. Composition B. Energy C. Temperature D. Rotation |
Temperature?
|
|
|
If you have two stars that are the same size but are different temperatures, which one is brighter?
|
The hotter star (blue) is brighter than the red one.
|
|
|
The AREA under the blackbody curve tells us what about a star?
|
Energy?
|
|
|
If you have two stars that are DIFFERENT sizes but are the same temperature which is brighter?
|
The bigger one is brighter than the smaller one.
|
|
|
What type of spectrum do neon signs produce?
|
Emission
|
|
|
We generally measure this from shifts in the wavelengths of spectral ines?
|
The Doppler Effect.
|
|
|
Which one of Kepler's Laws can be used to measure the mass of stars orbiting?
|
3rd Law
|
|
|
How do we determine the temperature of a star?
A. Its apparent magnitude B. Its color or peak of the blackbody curve C. The area under the curve of its blackbody spectrum |
B. Its color or peak of the blackbody curve
|
|
|
For thousands of nearby stars we can find?
|
1. The total luminosity
2. Temperature (color or spectral type) 3. Size (radius) 4. Distance 5. Composition 6. Rotation |
|
|
Stars are classified by their spectra as these spectral types?
|
O, B, A, F, G, K, M
|
|
|
Spectra tells us this about a star?
|
1. Temperature
2. Composition |
|
|
This shows luminosity vs. spectral type?
|
The Hertzsprung Russell (HR) Diagram
|
|
|
This goes from top left (hot and bright) to bottom right (cool and dim) on the HR Diagram?
|
The Main Sequence
|
|
|
90% of stars are in this stage of their lives on the HR Diagram?
|
The Main Sequence
|
|
|
Where is the Sun currently located on the HR Diagram?
|
The Main Sequence
|
|
|
There is a relationship b/w these two things for Main Sequence stars?
|
1. Mass
2. Luminosity |
|
|
These lie at the lower end of the main sequence are not only coll but also small (0.1 times the radius of the sun) and are not visible to the naked eye?
|
The Red Dwarfs
|
|
|
The giant stars are roughly how much larger than the sun?
|
10 to 100 times
|
|
|
The supergiant stars are as large as this?
|
1,000 times the sun's diameter.
|
|
|
These lie in the lower left of the HR Diagram?
|
White Dwarfs
|
|
|
These are among the hottest stars known, yet they are so small they have very little surface area from which to radiate, thus limiting them to low luminosities?
|
White Dwarfs
|
|
|
Although these are rare, they are visible even at great distances?
|
Luminous Stars
|
|
|
These are pairs of stars that orbit each other?
|
Binary Stars
|
|
|
Finding the real masses of stars involves studying these?
|
Binary Stars
|
|
|
Each star in a binary system moves in its own orbit around this, known as the balance point of the system?
|
The System's Center of Mass
|
|
|
What are the three kinds of binary systems?
|
1. Visual Binary System
2. Spectroscopic Binary System 3. Eclipsing Binary System |
|
|
In this type of binary system, two stars are separately visible in the telescope and we can watch the stars orbit each other over years or decades?
|
Visual
|
|
|
This binary system is found using a spectrum with the light from both stars and contains spectral lines from both?
|
Spectroscopic
|
|
|
This is the binary system when one star moves in front of the other, it blocks some of the light, and the star is eclipsed?
|
Eclipsing
|
|
|
The masses of stars range from this to this?
|
0.1 solar masses to nearly 100 solar masses.
|
|
|
This has about the same density as water?
|
Sun
|
|
|
These types of star are ONE THOUSAND times less dense than AIR?
|
Giants
|
|
|
These types of stars are about 1 MILLION times the SUN'S density?
|
Dwarfs
|
|
|
1 teaspoon of a white dwarf equals?
|
5 tons
|
|
|
Stars condense from this that exist throughout the disk of the galaxy?
|
Gas and Dust (aka- Interstellar Medium)
|
|
|
Very hot stars can excite clouds of gas and dust to emit this?
|
Light
|
|
|
Stars form in this?
|
Star Clusters
|
|
|
Because shorter wavelengths are scattered more easily than longer wavelengths, this occurs?
|
Blue light scatters more readily than red light.
|
|
|
O2 in the atmosphere scatters blue light, creating this?
|
A blue sky.
|
|
|
Because there is more atmosphere for light to go through and red light gets scattered, this occurs?
|
Sunsets are red
|
|
|
This is used to show the birth, life, and death of a single star?
|
HR Diagram
|
|
|
What is the first step of a star's birth?
|
Clouds of Gas and Dust Collapse (thought to occur as other stars die via supernova)
|
|
|
What is the second step of a star's birth?
|
Fusion
|
|
|
In Fusion, as the gas cloud collapses due to this, the core becomes hotter and the density inside the core increases?
|
Gravitational Forces
|
|
|
In Fusion, eventually the temperature and density reach a point where this can occur?
|
Nuclear Fusion
|
|
|
This is the combining together of light atoms, into heavier atoms?
|
Fusion
|
|
|
These are never hot enough to fuse hydrogen?
|
Brown Dwarfs
|
|
|
For all main sequence stars, the temp. and density in their cores are so great that Hydrogen atoms combine to make Helium atoms and release energy. This process is known as?
|
Thermonuclear Fusion
|
|
|
The sun converts hydrogen into helium to produce this?
|
Energy (warmth of the sun)
|
|
|
All Main Sequence Stars are in this?
|
Hydrostatic Equilibrium
|
|
|
This produces radiation (light) that creates an outward pressure?
|
Nuclear Fusion
|
|
|
During this, there is a balance b/w the gravitational collapse of the star pushing inward and the outward pressure produced by photons from nuclear fusion in the core?
|
Hydrostatic Equilibrium
|
|
|
It may take a few million years to get there but most stars spend 90% of their lives where?
|
On the Main Sequence
|
|
|
The Sun is how old and is expected to live how much longer?
|
5 billion and 5 billion
|
|
|
These stars last longer and more are produced? These stars burn out quicker?
|
1. M Stars
2. O Stars |
|
|
While stars are on the main sequence they fuse these and then these and other elements in the center of the star?
|
1. Hydrogen
2. Helium 3. CNO (Carbon, Nitrogen, Oxygen) |
|
|
These stars spend less time on the main sequence (aka their MS lifetime)?
|
More massive stars
|
|
|
When the star starts running out of hydrogen in the core, the outward pressure is less than the?
|
Gravitational Collapse
|
|
|
When core hydrogen fusion ceases, a main sequence star becomes this?
|
A Giant
|
|
|
During Giant Star stage, when a star colllapses inwards, this causes the layer just outside the core to become so hot and dense that this will being in the outer layer?
|
Hydrogen Fusion
|
|
|
This begins at the core of a giant star? What does it fuse into?
|
1. Helium Fusion
2. Carbon and Oxygen |
|
|
Life Stages for Stars Like the Sun (<8 M of the sun)?
|
1. Interstellar Cloud (gas and dust)
2. Main Sequence Star 3. Red Giant 4. Planetary Nebula and White Dwarf 5. White Dwarf (Dead Star) |
|
|
This is the dead star that remains in the center of the planetary nebula?
|
White Dwarf
|
|
|
What is the mass of a white dwarf? color? temp?
|
1. 0.98 solar mass
2. Blue-White (hot) 3. 45,000 K |
|
|
What is the brightest star in the sky, which is a visual binary star? What is it's most luminous member?
|
1. Sirius
2. Sirius B |
|
|
The white dwarf Sirius B is how many times fainter than Sirius A?
|
10,000 times
|
|
|
On Earth a teaspoonful of Sirius B would weigh how much?
|
11 tons
|
|
|
There is no fusion in this?
|
A dead core, white dwarf
|
|
|
An aging giant star can expel its outer atmosphere in repeated surges to form this?
|
A planetary nebula
|
|
|
By the time the Sun leaves the main sequence in another 5 billion years, this will occur?
|
It will have twice it's luminosity.
|
|
|
These stars burn fast and die quickly? These stick around forever?
|
1. Blue Stars
2. Red Stars |
|
|
What is the life span of blue stars? white stars? yellow stars? red?
|
1. 10 million years
2. 1 billion years 3. 8 billion years 4. 50 billion years |
|
|
Life Stages for High Mass Stars (>8 M of the sun)
|
1. Interstellar Cloud (gas and dust)
2. Big Main Sequence Star 3. Red Giant 4. Type II Supernova 5. Massive Star (neutron star) or Black Hole (really massive star) |
|
|
For High Mass Stars, gravity wants to do this to a star?
|
Collapse it.
|
|
|
A Supernova is considered this?
|
An implosion
|
|
|
This is caused by the violent, explosive death of a massive star?
|
Supernova
|
|
|
These can be bright as a whole galaxy?
|
Supernovae.
|
|
|
The collapsing outer layers of the star will collapse against and bounce outward off the compact collapse core in an explosive event sending out a shockwave. This is called?
|
Type II Supernova
|
|
|
During the Supernova, heavier elements are created from fusion events, like?
|
1. Magnesium
2. Lead 3. Gold |
|
|
What happens to the core after a supernova?
|
It depends on the mass. The large the mass the more it travels.
|
|
|
This is the remnant of a Supernova that exploded in 1040AD with legs that are filaments of gas that are moving away from the site of the explosion?
|
The Crab Nebula
|
|
|
What is left after some Supernova Explosions?
|
Neutron Stars (the core with remaining mass)
Very small about the size of a large city. |
|
|
One cubic cm of this (like a sugar cube) has the mass of about 10 to the 11th power KG (hundreds of pounds)?
|
Neutron Star
|
|
|
These have one gigantic atomic nucleus, so close together than no electrons exist?
|
Neutron Star
|
|
|
In Nov. 1967, Jocelyn Bell, grad student at Cambridge Univ, found a peculiar pattern in the data from a radio telescrope, this was the discovery of?
|
Pulsars (rotating neutron stars)
|
|
|
These are pulsars that rotate around once every 1,000th of a second and are the size of a large city?
|
Milisecond Pulsars
|
|
|
These are so massive and dense that light cannot escape and are the the remaining core of a star with a mass of more than 3 M of the sun, will continue to collapse into an infinitely small location in space?
|
Black Hole
|
|
|
Black holes can only be detected if this occurs?
|
Has a companion star, and it attracts material in an accretion disk.
|
|
|
This has no dimension but has mass?
|
A black hole
|
|
|
This is the boundary b/w the isolated volume of space-time and the rest of the universe?
|
Event Horizon
|
|
|
The radius of the event horizon is known as?
|
The Schwarzchild Radius (RS)
|
|
|
This is the radius within which an object must shrink to become a black hole and the point of no return for any object falling in later?
|
Schwarzschild Radius
|
|
|
A 3 solar mass black hole with have a Schwarzschild radius of about?
|
9 km (increases times 3, ex: 10 solar mass will be radius of 30 km)
|
|
|
If the sun were replaced by a 1 solar mass black hold what would happen to the planet's orbits?
|
They would not change at all. Black holes do not suck anything in.
|
|
|
Time slows down in curved space time. This is known as?
|
Time Dilation
|
|
|
For any black hole with a mass like a star this would happen to you?
|
Crused laterally and stretched longitudinally long before reaching event horizon.
|
|
|
The first X-ray binary suspected of harboring a black hole was?
|
Cygnus X-1
|
|
|
There are how many black hole candidates?
|
9
|
|
|
If the sun is approaching us, what would it's absorption lines do?
|
Shift toward bluer wavelengths (distance b/w lines does not change).
|
|
|
In an atom, if an electron jumps from energy level 1 to energy level 2, this becomes absorbed by the atom?
|
A photon
|
|
|
What color would categorize a G star?
|
Yellow
|
|
|
Two stars have the same size. If Star A has a larger luminosity than Star B, which is hotter?
|
Star A
|
|
|
The only way astronomers can determine stellar masses is by calculating the orbit of these?
|
Binary Stars
|
|
|
By studying many interstellar clouds and protostars at various stages of development, astronomers are able to determine this?
|
How stars are formed.
|
|
|
Pressure from nuclear fusion has this affect with a star?
|
Outward Force
|
|
|
Gravitational Force has this affect within a star?
|
Inward Force
|
|
|
How do outward and inward forces compare in a star like the Sun?
|
They are equal
|
|
|
A star uses this as an energy source by building larger atoms from smaller atoms?
|
Fusion
|
|
|
The sun is most made of this and it is in this phase?
|
1. Hydrogen
2. Plasma |
|
|
The sun shines because of?
|
Nuclear Fusion
|
|
|
Each second the Sun's mass becomes?
|
Smaller
|
|
|
The CNO cycle compares what kind of temperatures in comparison to the proton-proton chain?
|
High
|
|
|
This is the main energy source for low-mass main-sequence stars?
|
Proton-Proton Chain
|
|
|
What can initiate the collapse of an interstellar cloud and trigger the formation of stars?
|
Collision with another cloud.
|
|
|
As a protostar evolves its radius does this? Its temperature does this?
|
1. Decreases
2. Increases |
|
|
This is a protostar that is ejecting mass into space, exposing the new star for the first time?
|
A T Tauri Star
|
|
|
What is the event horizon of a black hole?
|
The boundary at which nothing, even light can return.
|
|
|
If the Sun is approaching s, what would it's absorption lines do?
|
SHIFT toward bluer wavelengths
|
|
|
This is not a life stage of the SUN?
|
Supernova (the sun will not ever go into a Supernova)
|
|
|
Which type of star is most expected to turn into a black hole?
|
O Dwarf
|
|
|
Which element is being produced the most at the center of the Sun right now?
|
Helium
|
|
|
What astrophysical phenomenon is responsible for producing the heaviest elements in the Universe such as gold and silver?
|
Supernovae
|
|
|
Why does the Sun not collapse from its own gravity?
|
Energy produced from thermonuclear reactions in its center creates pressure to balance the pull of gravity
|
|
|
A planet orbiting another planet is called a?
|
Extrasolar Planet
|
|
|
When were the first confirmed extrasolar planets discovered? How many have been discovered thus far?
|
1993, thousands
|
|
|
The area around a star where liquid water can exist is called the?
|
Habitable Zone
|
|
|
Location within a habitable zone depends on this?
|
The temp. The hotter the star the further out of the zone.
|
|
|
80% of stars in the galaxy are this?
|
Binary Stars
|
|
|
What was the first method used to detect exoplanets? What was the first planet discovered and when?
|
1. Doppler System
2. 51 Pegasi (hot Jupiter) 3. 1995 |
|
|
What was the first transiting planet?
|
HD 209458B
|
|
|
This gives us orbit size?
|
Transit Frequency
|
|
|
What can tell us if a planet is in a habitable zone?
|
Orbit Size and Star Temperature
|
|
|
What method is currently finding the most exoplanets?
|
Transits
|
|
|
Water has been detected on the atmosphere of this?
|
Hot Jupiters
|
|
|
Stars are how many times brighter than planets?
|
A billion times
|
|
|
This can block out stars to help view extrasolar planets?
|
A coronagraph
|
