We know that some solar systems in the Universe have planets within them known as the “Goldilocks Zone”, just like Earth. How is it the same technology used to discover these planets is not able to detect if life, especially the intelligent type, also inhabits them?

Question

Scientists are able to observe these planets from vast distances. You would think with technological capability like this that we would also be able to detect if planets in these zones possess life on them. Trying to understand how or why this is the case.

In: Planetary Science

Answer 1

We know rather a lot about stellar physics, so we can look at a distant star and determine fairly accurately how big and bright it is. With this information, we can figure out the range of distances from the star where liquid water would be able to exist on the surface of a planet orbiting the star. This is the “Goldilocks zone” of the star.

However, we do not have anywhere near the capability to see distant planets with any sort of detail. We can often see that a planet is there, and sometimes we’re able to tell how big the planet is and what the atmosphere is like, but unless there’s already an advanced civilization on that planet producing signals, we can’t tell what’s actually going on on the planet’s surface.