Shared Flashcard Set

Details

Assignment 3
Stars
22
Astronomy
Undergraduate 2
02/27/2012

Additional Astronomy Flashcards

 


 

Cards

Term
Which statement about stellar motion is incorrect
Definition
Proper motion is measured in intervals of 6 months
Term
A star has a parallax of 0.01 arc seconds. Its distance is
Definition
100 parsecs
Term
If Vega is apparent magnitute zero and Debeb first magnitude then
Definition
Vega is 2.5x brighter than Deneb
Term
A star's absolute magnitude is its aparent brightness as seen from
Definition
10 parsecs difference
Term
Two stars both have parallaxes of 0.023 inches but star A has an apparent magnitude of 2.3 while star B has a magnitude of 7.3. Which statement is true
Definition
Star A is both 100x brighter and more luminous than star B
Term
What physical property of a star does the spectral type measure?
Definition
temperature
Term
Which star would be the hottest?
Definition
B0
Term
What can be said with certainty about a red star and a blue star?
Definition
The blue star is hotter than the red star
Term
Compared to type A0 star, a type A9 star
Definition
is cooler
Term
The star's color index is a quick way of determining its
Definition
temperature
Term
The H-R diagram can plot
Definition
temperature vs. luminosity
Term
In the H-R diagram, what are the two most important types of data plotted?
Definition
spectral classes and absolute magnitudes
Term
On the H-R diagram, the Sun lies
Definition
about the middle of the main sequence
Term
On the H-R diagram, white dwarfs lie
Definition
at the lower left
Term
On the H-R diagram, red supergiants lie
Definition
at the top right
Term
A star near the lower right of the H-R diagram is likely to be
Definition
red, with low luminosity
Term
The Doppler shift is used to find
Definition
spectroscopic binaries
Term
Which type of binary do we get by information about looking at the intensity of light
Definition
eclipsing
Term
Binary stars separated enough to be resolved in a telescope are called
Definition
visual binaries
Term
The apparent angular movement of a nearby star against the background stars as a consequence of its motion in space is known as
Definition
proper motion
Term
The speed of a star, measured in a direction perpendicular to the line of sight from the Earth to the star, is known as
Definition
tranverse velocity
Term
Suppose that 2 identical stars are located such that star A is at a distance of 5pc ad star B is at a distance of 25pc. How will star B appear to star A
Definition
1/25 as bright
Supporting users have an ad free experience!