Can life exist on the 7 Earth-like planets recently revealed by NASA? Using the James Webb Space Telescope, astronomers will attempt to find out. Meanwhile, Spitzer, Hubble, and Kepler aim at collecting more information of the worlds beyond ours.
Humans have been curious about alien life for long now. Maybe, some distant Earth-like planet has flourishing life on its surface, and we just need to find it? This has been the aspiration for centuries and centuries. However, we have only recently found a set of planets resembling ours in size that are within our reach to explore the life prospects there.
NASA recently revealed that a star named TRAPPIST-1 located 40 light years away from us had 7 Earth-sized planets revolving around it. Given their similarity to our own planet, scientists have wondered whether these 7 worlds can support life. Perhaps, they have atmospheres? One of the researchers, NASA’s Exoplanet Program Scientist Doug Hudgins, explains that the James Webb Space Telescope, to be launched in 2018, will be used to answer the latter question. The newly-discovered heavenly bodies are the “best Earth-sized planets” to be characterised by the telescope, according to Hannah Wakeford Goddard Space Flight Center of NASA.
Webb will be using spectroscopy to examine light of different wavelengths in order to detect the presence of any chemical through their unique wavelengths, as compounds like water, methane, oxygen, and carbon dioxide (in the right proportions) are indicative of an atmosphere that can support life.
Scientists are currently testing the Webb Telescope to observe the planets in the infrared. The next step will be to determine the proportions of the compounds—if they are indeed in the atmospheres of these planets.
Webb will also be focusing on chemical biomarkers such as ozone: it is (possibly) indicative of life as its formation is dependent upon the existence of living (photosynthetic) organisms as it is produced through the interaction of light with oxygen released by the latter. The telescope will also scan for compound methane to retrace a biological source for the oxygen.
The planets in the TRAPPIST-1 system that are potential candidates for life are three, named e, f, and g. These three are located in the habitable zone, and will, therefore, be the main focus of study of Webb.
“This is the first and only system to have seven earth-sized planets, where three are in the habitable zone of the star,” says Wakeford. “It is also the first system bright enough, and small enough, to make it possible for us to look at each of these planets’ atmospheres. The more we can learn about exoplanets, the more we can understand how our own solar system came to be the way it is. With all seven planets Earth-sized, we can look at the different characteristics that make each of them unique and determine critical connections between a planet’s conditions and origins.”