Cuesta College, San Luis Obispo, CA
[20 points.] Determine which star (Arcturus or Vega) would be brighter, as seen from Earth, if they were both relocated to a distance of 10 parsecs away. Explain using the properties of apparent magnitude, absolute visual magnitude, and distance. Solution and grading rubric:
- p = 20/20:
Correct. Arcturus is farther away than 10 pcs and is already seen as brighter than Vega, which is closer than 10 pcs. Moving Arcturus closer, and Vega farther away, such that placing both at 10 pcs away would still make Arcturus brighter than Vega as seen from Earth. - r = 16/20:
Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors. - t = 12/20:
Contains right ideas, but discussion is unclear/incomplete or contains major errors. At least understands the difference between apparent (m) and absolute (M_V) magnitudes, and that smaller positive (or more negative) magnitudes are brighter. - v = 8/20:
Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. Garbled definitions/relations between d, m, and M_V. - x = 4/20:
Implementation/application of ideas, but credit given for effort rather than merit. - y = 2/20:
Irrelevant discussion/effectively blank. - z = 0/20:
Blank.
Section 30676
Exam code: midterm02Sys7
p: 33 students
r: 4 students
t: 5 students
v: 3 students
x: 1 student
y: 0 students
z: 0 students
A sample "p" response (from student 4351):
Another sample "p" response (from student 1237):
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