Astronomers Observe the Small Magellanic Cloud (SMC), a Not Very

question 16

Multiple Choice

Astronomers observe the Small Magellanic Cloud (SMC) , a not very dense, rather small galaxy near us. They notice that even those stars that formed recently have relatively few heavier elements (when compared to such recent stars in our Milky Way.) What is the likely explanation for this deficiency?

• A) most stars in the SMC don't produce their energy through the process of nuclear fusion
• B) most stars in the SMC finished going through their lives many billions of years ago
• C) because the SMC is small and its stars are widely spaced, the rate of star formation (and star death) is much slower there
• D) in small galaxies, only low-mass stars can form (and these do not produce supernovae)
• E) astronomers cannot come up with any explanation for this puzzling observation

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Definitions:

Shape Constancy

The recognition that an object's shape remains the same even when its orientation to us changes.

Retinal Disparity

This refers to the difference in the visual images that each eye perceives because of the different angles in which each eye views the world, contributing to depth perception.

Place Theory

Theory on how the inner ear registers the frequency of sound, stating that each frequency produces vibrations at a particular spot on the basilar membrane.

Cone Receptors

Photoreceptor cells in the retina of the eye that function best in relatively bright light and enable the perception of colors.