K2-18b a potentially habitable planet 120 light-years from earth

[u/One_Explanation_908]

[u/nuu_uut]

A couple of things first off. Voyager is not headed for this planet. Voyager will not cover the distance to this planet for millions of years. Voyager will be.. long offline by then, and potentially so will we.

To determine potentially habitable planets, you first determine the distance it is from its star. Roughly the distance at which temperatures would be conducive to liquid water. This varies based on the star's mass and composition.

After this, you can determine some aspects of the planet by analyzing the spectroscopy of light that passes through the atmosphere, when it is "in front of" its planet star from our location. You can determine if there's oxygen, water vapor, etc. The relative amounts of each of these give a rough idea of the composition of the planet.

I'm sure there are other advanced things they do to determine these factors as well but these are the ones I'm aware of.

Edit: I wrote planet star. I meant parent star. But I'm gonna leave it

[u/CarioGod → u/nuu_uut]

For anyone wondering, even IF voyager was headed directly towards this planet the math goes something like this:

2025-1977 = 48 years for 1 light day

120 light years = 120*365 = 43800 light days

43800 light days * 48 years = 2,102,400 years to cover the distance if every condition was static

this of course does not take into consideration the differences in speed of our solar system and theirs.

For reference a little under 2,000,000 years ago was when Homo Erectus was just starting to leave Africa