An eclipsing binary will
a. be more luminous than a visual binary.
b. also be observed as a spectroscopic binary.
c. give off most of its light in the infrared.
d. show a constant Doppler shift in its spectral lines.
e. show two stars with variable proper motion.
Question 2A total lunar eclipse is
a. visible only from the path of totality.
b. visible only during a new moon.
c. visible to all observers on the side of Earth from which the moon would be visible at that time.
d. an opportunity to study the corona of the sun.
e. none of the above
Question 3Spectroscopic binaries are difficult to analyze because
a. we can't measure the radial velocities of each star in the system.
b. we can't see the shape or tilt of the orbit.
c. we can't find the diameters of the stars.
d. we can't determine the luminosities of the stars.
e. the Doppler shift is not measurable.
Question 4On average the moon's umbral shadow is
a. to bright to produce a total solar eclipse.
b. to faint to produce a total solar eclipse.
c. to wide to produce a total solar eclipse.
d. too long to produce a total solar eclipse.
e. to short to produce a total solar eclipse.