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;
11 Cards in this Set
- Front
- Back
|
evolutionary track
|
represents changes in a star's temperature and luminosity on the H-R diagram; not its motion in space
|
|
|
interstellar medium
|
matter between the stars which contains at least 10% of all the known mass in our Galaxy
|
|
|
reflection nebula
|
bluish haze around certain stars (ex. Pleiades) caused by fine grains of interstellar dust that efficiently scatter and reflect blue light
|
|
|
interstellar extinction
|
when dense interstellar clouds dim or completely block the light from the stars behind them
|
|
|
interstellar reddening
|
when interstellar dust in fron tof a star scatters blue light making the star seem redder than it actually is: different from reddening caused by Doppler shift
|
|
|
Giant Molecular Clouds
|
concentrated vast amounts of interstellar gas and dust
|
|
|
supernova
|
a violent detonationthat ends the life cycle of a massive star
|
|
|
Nebulae, or supernova remnants
|
remains of dead stars scattered across the sky
|
|
|
Jeans instability
|
when a region of a cloud is sufficiently cold and dense, the gravitational attraction of the matter in this region overwhelms the pressure there and pulls the gas together to form a new star
|
|
|
protostar
|
newly formed object before it becomes a star
|
|
|
pre-main-sequence star
|
what a protostar becomes when mass accretion stops--some protostars that are incredibly massive begin fusing so quickly that they go diretly to the main sequence
|
