Observations show that elements with atomic mass numbers divisible by 4 (such as oxygen-16, neon-20, and magnesium-24 ) tend to be more abundant in the universe than elements with atomic mass numbers in between. Why do we think this is the case?
A) The apparent pattern is thought to be a random coincidence.
B) Elements with atomic mass numbers divisible by 4 tend to be more stable than elements in between.
C) At the end of a high-mass star's life, it produces new elements through a series of helium capture reactions.
D) This pattern in elemental abundances was apparently determined during the first few minutes after the Big Bang.
Question 2
How will the Kepler mission (scheduled for 2008 launch) look for planets around other stars?
A) It will look for Doppler shifts in stellar spectra.
B) It will be sufficiently powerful to take low-resolution photographs of planets orbiting nearby stars.
C) It will look for slight back and forth shifts in a star's position in our sky.
D) It will look for slight changes in a star's brightness that repeat at regular intervals.
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