Relative sizes of Kepler habitable zone planets discovered as of April 18, 2013. Left to right: Kepler-22b, Kepler-69c, Kepler-62e, Kepler-62f, and Earth.
Every day, astronomers, with the help of NASA's Kepler telescope, get closer and closer to finding more planets like our Earth that circle stars like our sun.
On Thursday, researchers announced the discovery of two new planetary systems, each which contain planets that circle a star similar to our sun, and within a distance that would allow that planet to support liquid water, also known as the "habitable zone." 
"With all of these discoveries we're finding, Earth is looking less and less like a special place and more like there's Earth-like things everywhere," said Tom Barclay, Kepler scientist at the Bay Area Environmental Research Institute in Sonoma, California, according to CNN's Elizabeth Landau. 
The "habitable" zone means that a planet is not too close to its host star that liquid water would boil away, and not too far that liquid water would freeze. It is in the perfect spot between fire and ice, William Borucki, Kepler's principal science investigator, said at a news conference on Thursday.
Kepler-62e and Kepler-62f were found in a five-planet system, all of which circle a star called Kepler-62. Kepler-62 is about 1,200 light years away from us.
Kepler-62e and Kepler-62f are somewhat bigger than Earth (they are known as super-Earths), but scientists say they are the best planet candidates for habitability found yet because of their size. Past candidates have been much bigger than Earth. 
Another newly discovered two planet-system, which circles a sun-like star called Kepler-69, includes one planet that orbits in the habitable zone. Kepler-69c is even bigger than Kepler-62e and Kepler-62f, however. 
Scientists don't know what kind of life is on these planets or even their exact composition — they could be rocky and Mars-like — but it does mean that we are well on the way to finding more planets like our own. 
These planets could hold alien species, or be habitable for colonies of humans. It's too early to tell.