Multiple Choice
Protostars, when they first form from the interstellar medium, are usually
A) very bright in ultraviolet light due to numerous flares that are hotter and brighter than solar flares.
B) detected by emission lines in their visible spectra, emitted by gas being blown off their surfaces into space.
C) easily detected because their light ionizes the surrounding interstellar gas, or reflection nebulae.
D) hidden from sight by dust clouds that emit infrared radiation.
Correct Answer:
Verified
Correct Answer:
Verified
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