Astronomy Set 2

Front 1

Open Cluster

Back 1

A few thousand loosely packed stars

Front 2

Globular Cluster

Back 2

Up to a million or more starts in a dense ball bound together by gravity

Front 3

Interstellar Medium

Back 3

the gas between stars

Front 4

Flattening

Back 4

collisions between particles in the cloud cause it to flatten into a disk

Front 5

Fusion will not begin in a contracting cloud if some sort of force stops contractions before the core temperature rises above ____

Back 5

10^7 K

Front 6

_________ cannot stop contraction because the star is constantly losing it through radiation

Back 6

Thermal pressure

Front 7

Main form of pressure in most stars

Back 7

thermal, depends on heat content

Front 8

Degeneracy pressure

Back 8

particles cant be in same state in same place, does not depend on heat content

Front 9

Brown Dwarfs

Back 9

degeneracy pressure halts contraction before core temperature becomes hot enough for fusion, they are not massive enough to start fusion, emit infrared light because of heat left over from contraction, luminosity gradually declines with time as it loses thermal energy

Front 10

____ pressure limits how massive a star can be without blowing itself apart

Back 10

Radiation

Front 11

Maximum radiation pressure thought to be

Back 11

150M Sun

Front 12

Life stages of low mass star

Back 12

11.5 million years. Protostar, yellow main sequence star, reg giant star, helium burning star, double shell burning red giant, planetary nebula, white dwarf

Front 13

Planetary Nebulae

Back 13

Double shell burning ends with pulse that eject the H and He into space, the core left behind becomes a white dwarf

Front 14

Stages of high-mass star

Back 14

5 million years, protostar, blue main sequence, red supergiant, helium burning supergiant, multiple shell burning supergiant, supernova, neutron star of black hole

Front 15

Supernova Explosion

Back 15

Core degeneracy pressure goes away because electrons combine with protons, making neutrons and neutrinos, neutrons collapse to the center, forming a neutron star

Front 16

_________ says that electrons must move faster as they are squeezed into a very small space

Back 16

quantum mechanics

Front 17

White dwarf cannot be more massive than

Back 17

1.4M sun (white dwarf limit)

Front 18

Accretion Disks

Back 18

Mass falling toward white dwarf from its close binary companion and has some angular momentum, the matter therefore orbits the white dwarf. friction between orbiting rings of matter in the disk transfers angular momentum outward and causes the disk to heat up and glow

Front 19

Nova

Back 19

The temp of the accreted matter eventually becomes hot enough for hydrogen fusion, fusion begins suddenly and explosively causing a nova

Front 20

Massive star supernova

Back 20

iron core of massive star reaches white dwarf limit and collapses into a neutron star, causing total explosion

Front 21

White dwarf supernova

Back 21

Carbon fusion suddenly begins as a white dwarf in close binary system reaches white dwarf limit, causing total explosion