Assertion: radio wave | /r/HasProperty | weak
Facets:
value: very
type: DEGREE
value: by the time
type: TEMPORAL
Source sentences:
text: Although these radio waves are very weak by the time they reach earth, they can be used by astronomers to form a more complete picture of the cosmos than can be seen with the eye alone, even with the aid of a telescope.
text: Since astronomical radio sources such as planets, stars, nebulas and galaxies are very far away, the radio waves coming from them are extremely weak, so radio telescopes require very large antennas to collect enough radio energy to study them, and extremely sensitive receiving equipment.