Alien Blood

Does anyone have and idea what alien blood chemistry would be like based on science and what we know abot space?

What we know of Space right now tells us that we might actually be alone after all, so... sorry.

it would be impossible to determine without a sample because look at our own earth. we have bacteria that don't even have blood so aliens might not even have blood. and there has been over 400 planet discovered from 1994 and they found almost a planet on every star that they looked at and that is only massive gas giants and a few rocky planets 5 to 10 times ans big as ours. that means that planets are extremely common and that is good for life. just take the numbers into account, there are an estimated 100 billion stars in our galaxy alone, that means if 1% of stars have planets and 1% of those have earth like planets there is still at least 10,000,000 or 10 million planets
and if 1% of those have life that is 100,000 and if !5 of those have intelligent life on them that is 1,000 planets with aliens and that would be such a big diversity of aliens. and the reason why they can't find planets smaller that 5 times ours size is because there gravitational affect is so small that they cant pick it up from earth. go and search on Google to find out how they find planets. and life is likely to be able to live on planets as big as 10 times ours. i think that life might even be able to live on Jupiter if it has a small rocky core the reason i say this is because there is living organism at 11 kilometers under the see, i know that Jupiter has much higher pressure but if the deference between our surface organism and the organism at 11 km can be so big then nothing stops life from living there. they might just not be so advanced they would likely only be single celled.

This would simply depend on what planets gasses the alien would be breathing, Or if the alien is breathing is the same way we do at all.. Our blood cels are blue but turn red because of the hemoglobin that coats the cells when in contact with oxygen
A alien might for instants have a compleatly different type of resperatory system ie breath the gas they need through skin or simply convert a radiation or there worlds energy into a way they can use it for there own use.
Let's just say they live in a similar world as our own and breath in the same way we do and have a chemical similar to hemaglobin that coats there blood cells. Then it would only depend on what colour there blood Is without any oxygen say it was red then when in contact with oxygen would proberly turn blacK, yellow could turn green so on and so on

but I don't think we will find out for along time.

or maybe aliens have already contacted and visited, maybe the governments is just hiding it and working with them to develop technologies.