June 2010 LSAT Section 5 Question 22

The passage states which one of the following?

kassidee on February 20, 2020

example 7

Is E right because the passage is specifically referring to their light? Stating that the objects light can be seen without it existing?

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SamA on February 20, 2020

Hello @kassidee,

Yes, the implication here is that the light from quasars can be seen after the quasar has burned out.

For anything that far away to appear from earth (AFE), it would have to produce more light than 90 billion suns (90B).

AFE - - - - - - - > 90B

Nothing that burns at that rate (90B) can exist for more than 100 million years (100M).

90B - - - - - - - - - - - - > <100M

From this, we know that quasars can't exist for longer than 100 million years. But if their light takes 500 million years to reach earth, then we are only seeing dead quasars.