Fill in the blank: Elements heavier than hydrogen and helium constitute about ________ of the mass of the interstellar medium.
A) 0.002%
B) 2%
C) 70%
D) 98%

Question

Quizplus · Accepted Answer

Elements heavier than hydrogen and helium, often referred to as "metals" in astronomical terms, make up about 2% of the mass of the interstellar medium. The rest is primarily hydrogen and helium.

Fill in the Blank: Elements Heavier Than Hydrogen and Helium