Save
Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
focusNode
Didn't know it?
click below
 
Knew it?
click below
Don't know
Remaining cards (0)
Know
0:00
share
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Spectra

TermDefinition
Magnitude refers to the apparent brightness of a star and is not a fundamental property of the star. However, the greater the flux, the smaller and more negative the apparent magnitude.
Second law of thermodynamics Heat flows from hot objects to cold objects -or , in other words, hot objects radiate more energy into space than colder ones
Blackbody Radiators Radiate EM ration into space at all wavelengths irrespective of size, shape or composition
Max Planck BB equation His equation describes the energy flux of BB at a specific wavelength for a specified temperature
Temperature temperature is a measure of heat energy
The Kelvin Scale Equation T(Kelvin) = T(Centigrade) + 273
Wiens Law(temperature of any star anywhere in the universe) lamdamaxT = 2.8977 x 10^-3. Where lamdamax in meters, T in Kelvin
3 types of Spectra Continuous(blackbody) spectra, Emission spectra, Absorption Spectra
Continuous(Blackbody) spectra Hot solids, liquids of dense gases. EM radiation produced at all wavelengths
Emission Spectra Hot, low density gas. EM radiation at very specific wavelengths. Hot interstellar gas clouds produce such spectra.
Absorption Spectra Produced when light from a continuous spectrum is viewed through a lower density, lower temperature gas. Absorption lines are seen at very specific wavelengths. Stars produce absorption line spectra.
Spectra type graphs D4
Stellar absorption Lines Absorption line spectra produced by a blackbody radiator surrounded by a lower temperature gas envelope
Photosphere Cool, low density envelope where the absorption lines form.
Emission Lines In general, emission lines are associated with hot low density gases.
Three processes are at work in Emission lines 1.High temperature-many high energy collisions. 2.Collisions between atoms places them in an excited state. 3.Between repeat collisions an excited atom releases a photon which carries away their excitation energy and produces emission line
Photon Burst or packet of EM radiation with energy (E = hf)
Spectral analysis Each species of atom has a unique set of absorption/ emission lines
Spectral Classification Classify stars according to their spectral lines(key idea is to use 'strength' of hydrogen lines)
The spectral classification scheme OB AF G KM
OB >30,000(O) 10-30,000(B) hottest and most luminous stars (Blue)
AF 7500-10,000(A)6000-7500(F) Strongest hydrogen lines(blue-white)
G 5000-6000 (G)Sun = G2 star(yellow)
KM 3500-5000(K) <3500(M)Coolest and least luminous stars (red)
Created by: davidvachon1
 

 



Voices

Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards