Correct answers for Exam 1, AST 2008, Fall Term, 2007-08

The questions are listed in an order different from that in your exam because question numbers differ from one exam to another.



"An important role of the telescope ...."   form an image, part of which can be sent into the spectrograph


"Planet Saturn, about twice ..."   as accurate as with Jupiter because .....

"According to a Kepler Law ..."   the Sun-planet line in any part of a planet's orbit in a given amount of time

"Suppose sunlight that is reflected ..."   dark line; the Sun is a normal star and ...

"In class we considered the possibility ..."   exactly the same phenomenon because one category can be shifted ...

"Astronomical (visual region) spectra in image ..."   black and white (grayscale); their useful information is in ..., while colors of spectral regions are already known

"A figure on the exam depicts Tycho ..."   up-down and right-left positions of a sky object

"A rock weighs 100 pounds ..."   50 pounds

"An accurate drawing of an ellipse ..."   adding the distances from two foci gives the same ...

"Triangulation (used for distances on landscapes) ..."   parallax needs a background ....

"An ideal radiator (blackbody) has ..."   no bright or dark spectral lines

"The eccentricity of a star's parallactic ellipse depends ..."   sky location with respect to the plane of Earth's orbit

"Dark spectral lines in astronomical spectra ..."   narrow parts of spectra with less light than the immediately surrounding regions

"James Bradley discovered that stars ..."   Earth's changing orbital velocity

"Among astronomical units (AU), light years (LY), ..."   LY and pc

"Possible units for a star's proper motion ..."   degrees per day

"In the 1830's, F.W. Bessell ..."   parallax; has a large proper motion ...

"Figure 1 was used in class to ..."   travel without need of a medium

"Spectral lines formed by a typical astronomical spectrograph ..."   geometrical form as the spectrograph slit

"Which of the following comes closest to representing ..."   92 percent hydrogen, 7 percent helium ...

"A star is running away from an observer ..."   1.0 nanometers toward longer wavelengths

"Suppose an observer measures the sky location ..."   the star's proper motion but not its parallax could be measured

"Although Kepler's laws of planetary motion do not ..."   much closer to the Sun than to Jupiter

"If G. Galilei's experiments on falling bodies ..."   the same on a given planet but differently from planet to planet