Exam 3 Flashcards
Betelgeuse has an apparent magnitude of 0.50. Tau Ceti has an apparent magnitude of 5.68. Which looks brighter in the sky?
a. Betelgeuse
b. Tau Ceti
A. Betelgeuse
You want to see Uranus with your eye. In Jan m=5.6 in Aug m=6.5. When should you watch for Uranus?
A. Jan
B. Aug
A. January
You have two light bulbs 25 Watt and 100 Watt.
A)If you plug them both into the same type of lamp and put them 3 feet away, which looks brighter?
A. 25 W
B. 100 W
B
You have two light bulbs 25 Watt and 100 Watt.
B) Now move the 100 Watt across the street?
A. 25 W
B. 100 W
maybe B
You have two light bulbs 25 Watt and 100 Watt.
C) Now move the 100 W two blocks away?
A. 25 W B. 100 W
probably A
Which Star is Brighter (giving off more light)?
Sirius M = 1.5 OR Betelgeuse M= -5.1
Vega M = 0.6 OR Proxima Centauri M = 15.4
Capella M = -0.5 OR Arcturus M = -0.3
Betelgeuse, Vega, Capells
Apparent Magnitude
Apparent Brightness or Brightness is measured using
devices – watts per square meter
Absolute Magnitude
the apparent magnitude the star would
have at 10 pc and compare to each otherc
Luminosity
the total amount of
energy per second a star emits over the whole surface of the star.
Emission Nebula
is a nebula formed of ionized gases that emit light of various colors.
Reflection Nebula
is a cloud of gas and dust which does not create its own light, but instead shines by reflecting the light from nearby stars.
Dark Nebula
a nonluminous nebula of dust and gas that is observable because it obscures light from other sources.
Reaching end of Main Sequence Life
Core shrinks, increases density and fusion rate, heats the outer layers which then expand
solar prominences
filaments seen on the side
Photosphere
The deepest layer we can see, This area contains the Sunspots
Chromosphere
Literally the Sphere of Color
Spicules
Spikes of chromosphere’s material which stick up into the corona
Sunspots
Irregularly shaped dark regions in Photosphere, They are dark looking because they are cooler portions of the sun
Filaments
dark material arching high up, following the magnetic field lines
Stellar Evolution
Hydrogen depleted in core
He Core shrinks – heats up
H shell fusion– expands atmosphere
Star goes to Red Giant Branch
He core fusion begins by triple alpha process
The outer layer expands, cools off, gets bigger and brighter.
planetary nebula
The hot core emits ultraviolet radiation which excites the gas in the expanding atmosphere - glows
Supernova Remnants
Notice the remnants have no shape, and are less dense then the formation nebula
