Scientists are closer than ever to finding extraterrestrial life. Here's how they hope to do it.
Alien life has gone from science fiction to a real possibility
Step 1: Survey our solar system's ocean worlds
Step 2: Explore nearby ocean worlds with follow-up probes
Step 3: Bring ocean samples back to Earth
Step 4: Find planets in other solar systems
There are a few other methods
Step 5: Narrow down the list to planets suitable for life
The good news is that there are definitely some exoplanets out there that meet this criteria. Scientists have already spotted about a dozen planets that are relatively close in size to Earth and which may lie in their stars’ habitable zones. In July, for instance, astronomers discovered Kepler-452b, which is just 60 percent bigger than our planet and considered Earth’s closest twin yet.
The catch is that our current telescopes aren’t optimized to analyze these planets and look for signs of life. (Ironically, the Kepler telescope scientists currently use is too powerful — it was built to observe distant portions of the Milky Way, not to look for planets relatively nearby.) So scientists are building more suitable telescopes. NASA’s Transiting Exoplanet Survey Satellite (TESS), set to launch in 2017, will be the first space telescope specifically designed to analyze exoplanets.
Step 6: Scrutinize the atmospheres of the most promising exoplanets
Step 7: Search for signs of life in these atmospheres