Is there even any general moral imperativ, that every or at least most cultures agree with, which says that we should not contaminate other planets?
No.
Or is there any entity on this planet, that could claim it has legitimate interests (or even ownership) in keeping the atmosphere of Mars clean, which should prevent India from sending people to Mars in a way that we don't like?
Again, im my opinion the answer is no. Why? Because there are enough planets that every human being on earth could have its own.
We could also look at it from the benefits vs risks perspective.
Here I also reach the same conclusion. The risk of having contaminated one planet with organisms is almost non-existent compared to the potential benefits of making another step towards the colonisation of other planets.
Once our technology gets better, and we can reach to more distant places, you can have any amount of pristine and untouched planets you could ever want.
But first we've got to improve our capabilities by actually trying it.
> Because there are enough planets that every human being on earth could have its own.
Bro, we're never reaching those planets, FTL travel is a fantasy. Are you really willing to bet whatever life is on Mars on the hope that humans will someday be able to travel faster than light? What we could learn from extraterrestrial life, even if it's only microbes, could open vast new areas of biology research - potentially curing diseases or teaching us to survive in a much warmer Earth.
If you accept the ability for people to travel to and live on other bodies in the solar system, it's very plausible to assume that people can move between star systems, without any scifi stuff like warp drives or wormholes.
So your argument is basically "don't do it, because what I believe in is more probable than what you believe in" even though there's no way to calculate those probabilities.
No, my argument is that there is no moral standard regarding this issue, that the majority on this planet agrees with, that there is no legitimate interest or ownership that could force anyone from doing otherwise, and that the potential benefits (colonization, resources, space) outweigh the belief in something that might be on Mars.
Meanwhile your argument is based beliefs where you can't even possibly calculate a probability, just like the belief in god.
What we have is our tools and capabilities to try and work with what we can reach at the moment in our solar system.
No.
Or is there any entity on this planet, that could claim it has legitimate interests (or even ownership) in keeping the atmosphere of Mars clean, which should prevent India from sending people to Mars in a way that we don't like?
Again, im my opinion the answer is no. Why? Because there are enough planets that every human being on earth could have its own.
We could also look at it from the benefits vs risks perspective.
Here I also reach the same conclusion. The risk of having contaminated one planet with organisms is almost non-existent compared to the potential benefits of making another step towards the colonisation of other planets.
Once our technology gets better, and we can reach to more distant places, you can have any amount of pristine and untouched planets you could ever want.
But first we've got to improve our capabilities by actually trying it.