(UNEB 2019) Interpretação

In January, two astronomers reported new evidence of a massive, shadowy Planet Nine tracing the outer limits of the solar system. It has a mass 10 times that of the Earth, and its orbit takes it 20 times farther from the sun, on avarage, than Neptune. The catch? Konstantin Batygin and Mike Brown of Caltech haven't seen it - they inferred its existence from the behavior of smaller objects nearby that appear to be subject to its gravitational pull. Now the search is on. Brown predicts astronomers will find it by 2018.
According to the text, the only statement that is not true about Planet Nine is that it
01) is a hypothetical planet.
02) repels objects that orbit nearby.
03) is far away in our solar system.
04) has and estimated mass of ten Earths.
05) is expected to be spotted this year.

Alguém pode me dizer por que a 5 está errada? Achava que ela estava correta pelo trecho do texto: Brown predicts astronomers will find it by 2018.

Qual a data dessa matéria? Essa frase que você citou pode ter sido usado no sentido de achar o planeta ATE 2018, um exemplo desse uso:
Mother- Son, please clean your room.
Son- Ok, mom, I will do it by the end of the day.
Mais essa interpretação só vale se a reportagem fosse de 2017, por exemplo.