for my space alien brothers and sisters.

Just as long as they believe in the right to life from conception to birth and don't want same sex marriage.

Back when I lived there, we had a radio comedian (who became quite a local celebrity) who had a regular radio show titled "Space Commander Wack, Space Commander".  He featured a sidekick named Stupid Larry.  The show was very popular, and I still miss it, though its progenitor long ago retired.  Still, Space Commander Wack and Stupid Larry visited multiple star systems with multiple alien races.  I still have fond memories of these characters, along with their pet named Glorph, billed as "the formerly immortal dead Martian dog".

I wonder if the Vatican was tuned in all along?  Publication of this story in L'Osservatore Romano makes me wonder.

not already covered in the homilies of Father Guido Sarducci.

What happens when these space aliens don't have any idea about Jesus. Wouldn't god have sent his only son to every planet with sentient life? What would it say about it if they had never developed the part of their brain that holds religious belief, and the concept of god was as foreign to them as it is to me?

Or, if they do have knowledge of Jesus, will he be portrayed as a little green man with flowing purple locks, a blue beard, and piercing, pink, slitted eyes?

Of course it is.

There have been some great SF stories addressing the points raised in some of the comments - I recommend particularly the anthology (now out of print, no doubt) titled "Perpetual Light", and Mary Doria Russell's novel "The Sparrow".

The setup for The Sparrow is one of the best things about it IMHO: the SETI program discovers alien signals from a relatively nearby star. And while the UN dithers about what kind of expedition to put together, who's going, who's paying, who's in charge, etc and so forth.... the Vatican quietly and quickly sends out a ship staffed with both scientists and theologians, because indeed, the discovery of intelligent space aliens will raise a whole bunch of theologically important questions:

• do they have souls?
• are they fallen creatures in need of a savior?
• Did they get a savior? or was Jesus it?

and so on and so forth.

What if The Space Pope decides that we need to convert to Space Catholicism?

it is impossible for Earth to be home to the only intelligent life in the universe.  http://www.flicklife.com/08b59454a9a...

And I assume, for the RCC, that the temperamental toga-clad super Santa in the sky doesn't count as an alien life form "out there,"