Shared Flashcard Set

Details

Physics 1446 Test 2 Ch12
Test 2 Black Holes life of stars
27
Astronomy
Undergraduate 1
10/17/2009

Additional Astronomy Flashcards

 


 

Cards

Term
Interstellar Matter
Definition
the matter between two stars
Term
What is Interstellar main constituents?
Definition
gas and dust
Term
Describe the Shapes of Gas Particles
Definition
Particles are basically spherical
Term
Describe the Shapes of Dust Particles
Definition
Individual particles are elongated, larger scales are very complex
Term
Gas is made up mostly with what particular molecules?
Definition
Hydrogen and Helium
Term
What wavelengths can be used to observed interstellar matter?
Definition
Infrared and Radio
Term
Define: Extinction
Definition
general dimming of starlight by interstellar matter
Term
Define: Reddening
Definition
the dust preferentially absorbs short-wavelength radiation. Because of this, blue part of light from distant stars is obscured more than red. So in addition to being generally diminished in overall brightness, stars also appear redder than they really are. 
Term
Stars form in what kind of cloud?
Definition
GMC Giant Molecule Cloud
Term
What is GMC?
Definition
Giant Molecule Cloud are giant clouds of interstellar gas and dust constituting mainly molecular hydrogen (H).
Term
What is the Diameter of a GMC?
Definition
50-300 light years
Term
What is the temperature range of GMC?
Definition
10-30K
Term
What trigger star formations?
Definition
when GMC collapses under its own gravity
Term
So what is the collapsed of GMC is stimulated by?
Definition
cloud cloud collisions, supernova blast wave,starlight(shockwaves)by type O & B stars
Term
How long does the contraction of GMC usually takes?
Definition
millions of years
Term
GMC contracts and forms dense core of gas & dust called______?
Definition
Bok gobules
Term
As a protostars grows and got hotter it becomes a what?
Definition
pre Main Sequence Star
Term
What is a Reflection Nebula?
Definition
: bluish; mainly due to scattering of light by the dust particles; not necessarily around hot stars.
Term
What is Emission Nebula?
Definition
reddish; mainly due to the gas surrounding the hot O and B type stars.)
Term
Depending on the _____, stars take different time to reach to main sequence.
sequence,
Definition
Mass
Term
What are Brown Dwarfs?
Definition
failed stars that never began burning because they are too small & don't generate enough heat
Term
Define: Wide Binary star
Definition
the separation between the two stars is larger than the largest radius that either star will ever reach
and hence the two stars will go through their entire life
cycles independently.
Term
Closed Binary Star
Definition
have shorter orbital periods, and the two stars are closer than the gravitational pull between them. There is then the possibility that one star may influence the other and completely new
evolutionary pathsare opened up for the two stars.
Term
Roche Lobe
Definition
is the teardrop region or volume around a star in binary system
Term
Langrangian point
Definition
gravitational pull are exactly balancing each other
Term
What are the four types of Binary Stars!
Definition
detached, semi attached, contact and over contact
Supporting users have an ad free experience!