Stellar 1 Flashcards
(13 cards)
What are constellations and how many official
Stars grouped together based on patterns and shapes we see in them, 88
Two ways stars can be named and how
Bayer Letters: in order of brightness (greek letters)
Flamsteed Numbers: west to east (1,2,3..)
What is the magnitude to brightness ratio
lower magnitude = brighter star.
Logarithmic scale.
A difference of 5 magnitudes is a brightness ratio of exactly 100
What magnitude of stars are visible to the naked eye
6
Magnitudes of the sun and moon
sun: -26.7
moon: -12.6
What is the inverse square law in general
light from stars spreads out as it travels to us
An easy way to calculate the distance from a star
annual parallax
What is 1 AU in km
100 million
As the Earth orbits the sun, what happens to the position of the stars
close stars appear at a different position in the sky with respect to distant background stars
What is the parallax angle and how do you calculate the distance
The change in the stars position is measured by the parallax angle.
Distance (parsecs) = 1/parallax (arc seconds)
What is proper motion
the change of a stars position due to this relative motion
Would a closer star have a higher or lower proper motion
higher
Which star has the highest proper motion
Barnards star
