Sol-based instruments were enough to tell if there was a life-bearing planet, and to learn much of its detail.
Oh, yes, the hopefully life-bearing planet had to possess an atmosphere, too, but that wasn't a serious constraint.
"The hazy moon may hold clues to how the primitive Earth evolved into a life-bearing planet."
So when it turned out to have a life-bearing planet, the discovery seemed to strike at the foundations of astrophysics.
This was a mining colony, with no life-bearing planets.
A life-bearing planet without technology is not what we're looking for.
It is arguably a special case in planetary science, the Earth being the only known life-bearing planet.
Upon arrival there, you will make observations of life-bearing planets.
These are considered poor candidates for hosting life-bearing planets as their unpredictability and energy output changes would negatively impact organisms.
That argument overlooks how similar the environments of life-bearing planets are, sir.