We’ve only been emitting radio for around 100 years
We’we been emitting the presence of oxygen in our atmosphere for about 1 billion years. Every nontrivial alien would notice this.
You don’t necessarily spend a bunch of money on sending a contact message to every planet with oxygen.
Why not? Or rather make an expedition there ASAP.
At least. More likely, you have a large colonization plan underway and this planet is in your path anyway.
We’we been emitting the presence of oxygen in our atmosphere for about 1 billion years. Every nontrivial alien would notice this.
You don’t necessarily spend a bunch of money on sending a contact message to every planet with oxygen.
Why not? Or rather make an expedition there ASAP.
At least. More likely, you have a large colonization plan underway and this planet is in your path anyway.