Question

Astronomy Ranking Task: Doppler Shift Exercise #4   

Description: An important line in the absorption spectrum of stars occurs at a wavelength of 656nm for stars at rest. Imagine that you study five stars (A-E) from Earth and discover that this absorption line is observed at the wavelength shown in the table below for each of the five stars.



STAR Observed Wavelength of Absorption line A 650 nm B 663 nm C 656 nm D 657 nm E 646 nm



A. Ranking instructions: Rank the size of the Doppler shift (from largest to smallest) observed tonight for the light from each star (A – E).

Ranking Order: Largest 1 ____ 2 ____ 3 ____ 4 _____ 5 _____ Smallest

Or, the Doppler shift of the light from the stars would all be the same. _____ (indicate with a check mark)

Carefully explain your reasoning for ranking this way: ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________


B. Ranking instructions: As observed tonight, rank the speed of the stars (A – E) from moving fastest toward the Earth, through not moving at all, to moving fastest away from Earth.

Ranking Order:   

Moving fastest toward 1 ____ 2 ____ 3 ____ 4 _____ 5 _____ Moving fastest away

Or, all the stars would have the same speed _____ (indicate with a check mark)

Carefully explain your reasoning for ranking this way: ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________

Answer 1

LD 2 ㄩ