Bryson Reading Chapter 2-3

"distant stars they can infer the size and character
and even potential habitability of planets much too remote to be seenplanets
so distant that it would take us half a million years in a spaceship
to get there. With their radio telescopes they can capture wisps of radiation
so preposterously faint that the total amount of energy collected from outside
the solar system by all of them together since collecting began (in
1951) is "less than the energy of a single snowflake striking the ground/' in
the words of Carl Sagan."

This was the most striking to me , simply because it was the opening paragraph of the article so it had to be mind capturing to pull the reader in and thats exactly what happen to me. Im confused as to how they can capture the total amount of energy by collecting it from outside the solar system? it seems like it would be nearly impossible to collect energy from planets from so far away that we wouldnt be able to get there for half a million years traveling in a spaceship.


My question is why can we see and take photos of these planets that are so far away but we will never be able to actually see them up close in person? There is probbly so many things in space that would be benifitual for us to know that could possibly hurt or help our planet in the near future. Like how James Christy discovered pluto had a moon on it , leads us to finding out other things about these planets.

My Other question is how do we know these facts about these planets if weve never actually visited them like in the article it mentions that Jupiter and Saturn are about 4.5 trillion miles away. How could they possible know that from looking at a picture or a radiation telescope?

Bryson Reading

"The average species on earth last for only about four million years so if you wish to be around for billions of years,you must be as frickle as the atoms that ,atoms that made you."

My question is if what the quote above is saying is true does it mean that there wont be human species in four million years?

But don't species Evolve with time so there will be different type of the same species.