We know that aliens are among us.  The United States wouldn't spend so much time tracking down the illegal ones if that weren't true.  But recent discoveries of nearby Earth-like planets are raising questions about that other kind of alien... aliens from outer space.  Chances are they're out there somewhere.

USA Today reported Wednesday that a planet the size of a 'jumbo Earth' has been found circling a nearby star.  Dully named LHS 1140b, scientists say the planet is exposed to enough light from its star to allow for liquid water, a requirement for life as we know it here on Earth.  The great thing for astronomers is that 1140b is close enough that they may be able to learn more about it, especially after the new James Webb Space Telescope is launched next year.  It may even be able to tell us if there is oxygen there.  But don't expect little green men like Marvin the Martian to arrive on the Earth Express any time soon.

Just because a planet has all the conditions necessary for life to evolve doesn't mean life actually evolves there.  Most of the articles I read about life not on Earth talk about microbes.  If you were wondering why we haven't picked up radio transmissions from our fellow interstellar life forms, one reason might be that microbes can't send radio transmissions.

AliensAt the same time you have to believe that we are not unique, if only because the universe is so big.  So far we have only discovered a handful of planets that may support life as we know it.  Along with 1140b there are the seven planets in the TRAPPIST-1 star system, also relatively nearby.  Proxima b is a planet that orbits around Proxima Centauri that might have water, and it would be convenient if it had fellow life forms, because it's the star closest to our own solar system.

Not that we could just hop on the express star ship and go there for a day trip.  Let's face it, it takes more than nine years to get to the only planet (or former planet) with the same name as a Disney character, so we're not talking about a day trip when we talk about going to Proxima Centauri.

It takes about 54,400 years to get there at 52,000 mph. My Corolla can't even get there that fast.  It would take the Starship Enterprise almost a whole day to get there at Warp 9, 1,516 times the speed of light.  Since we don't have FTL (Faster Than Light) vehicles at the moment, there may be a bit of a wait before you can take that trip.

That's why the four and a quarter light years between the Sun and Proxima Centauri are thought of as only relatively close.  When you consider that all the other star systems are much farther away, the chances of visiting out 'neighbors' is low.  But also consider how many stars there are.  To quote the late Carl Sagan, (doing my best Carl Sagan impression) billions and billions.

That bigness suggests that somewhere there are other planets that has people of one sort or another.  If it happened here why wouldn't it happen on other planets?  And that's just life as we know it.  What about life as we don't know it?  What if they didn't invent radio, but did invent some other form of communications technology that we haven't invented?  What if their language isn't based on sounds?  Surely with so many variables life evolves in different ways on different planets. 

The chances of encountering aliens from outer space are fairly low.  They are probably having as much trouble locating us as we are trying to find them.  It is certainly true that we are not alone, but for all practical purposes we pretty much are.

If aliens ever do make it to Earth I hope we'll treat them better than we are currently treating the Terran variety.  After a trip that long the only polite thing to do is to offer them a drink.  And maybe a doughnut.  Because deporting someone back to their home planet 54,000 years away is just plain rude.