In paragraph 3, what can be inferred from Hartley’s comment “So I thought it might be a comet”?

A.
Hartley needed to get a second opinion about his observations.

B.
Based on his experience, Hartley believed the image was a comet.

C.
Based on his experience, Hartley believed he was looking at an asteroid.

D.
Hartley was unsure what he was looking at because of his unfamiliarity with comets.