The 20 Possibly Habitable Exoplanets Where We Might Find Alien Life
Image Credit: NASA
The search for extraterrestrial life is one of our most enduring mysteries, but how do we know the aliens we find will be anything like us?
With scientists speculating about the possibility of aliens all living deep underwater on frozen planets, there comes the question: If there is intelligent life out there in the universe, how comfortable would we be if we decided to visit their home planets?
Star Trek and Star Wars, as well as plenty of other pulp sci-fi stories, have sold us the idea of all alien worlds being relatively comfortable and warm – we can just beam down to visit our intergalactic neighbors without the need for a spacesuit, let alone an air conditioning unit.
In spite of this, we haven't actually seen all that many planets thus far that exist in a comfortable climate, where humans can exist without either freezing or boiling to death in a matter of minutes.
Thankfully, that's now changed, thanks to an analysis of existing data from the Kepler telescope.
Scientists taking another look at data collected by the Kepler space telescope between 2009 and 2013 think they might have spotted several Earth-like planets that are hiding off in another solar system. We won't be going there anytime soon, but we can at least speculate about the kinds of worlds they must be.
A team from SETI (ever-eager to spot aliens wherever they may lie), led by astronomer Susan Thompson, have identified 20 potential planets that were overlooked at first.
These worlds orbit their stars at a far enough distance to ensure that they're not too hot, but should also be nice and snug, as they're not far enough away to make things uncomfortably cool for any colonist who might end up in the area.
The reason these planets weren't spotted sooner comes down to the way that astronomers have been looking for orbiting bodies when observing stars from a distance.
Planets don't glow bright on the telescope's display, so the only way to identify them is to watch for their shadows moving in front of the sun - if they're spotted several times, astronomers are willing to believe that they're actually in orbit.
In order to spot a planet that similarly exists in the Goldilocks zone, we must train the telescope on a single star for several years in order to spot the planet whenever it reaches the same point in its orbit. Because of the enormous hassle involved in such planet detection methods, most planets that have been categorically confirmed up to this point have been ones that orbit their stars very closely, completing a full cycle in just a few days.
Thompson's team has taken a second, closer look at the initial data, and has decided that, while about 20-30 percent of the shadows spotted may be anomalies or errors in the data, there could well be some genuine planets out there that have a similar rotation period to Earth.
The most intriguing of these worlds is an exoplanet KOI-7923.01, which has an orbit of 365 Earth days, and which is just fractionally smaller than our own planet.
It's entirely possible that this world is a solid doppelganger for Earth, and if so, it could have local temperatures and gravity that would be very similar to our own.
We're not exactly going to get a good look at this far off planet any time in the near future, but it's nice to know that we're not the only world that's hanging out in the Goldilocks zone.
Who knows? Maybe in decades or centuries to come, this planet could become the perfect place for Earthlings to migrate to once our own planet has been completely and thoroughly trashed.