Most scientists today believe we are not the only beings in the universe. In fact it is often theorized that life may have originated on many of the billions of planets which are thought to exist within the galaxy in a similar manner as life began here on Earth. The question however which has dawned or minds for centuries on end and can only be answered by way of scientific investigation is; What is the next step for mankind in discovering another life form in the galaxy?
Can you picture yourself sometime in the near future pointing to a distant star and saying "that star has an orbiting planet filled with lifelike beings just like Earth"?
Many astronomers believe that almost ever star found within the galaxy known as the Milky Way has at least one celestial body much like Earth.
Mankind's quest to study the stars and the planetary systems around them have led to the development of several ground-based as well as spaced-based research facilities such as the Spitzer Telescope, the Hubble Space Telescope and the Kepler Space telescope by NASA. Many of these telescopes today have the ability to not only look at the stars within the Solar System but can also tell if there are any orbiting planets. Furthermore astronomers today by using these telescopes can determine whether the observed planets orbiting a star are at the ideal distance to sustain water which would indicate the strong possibility of life on that planet
This quest to find alternate life on another planet by NASA will continues in 2107 with the launch of the Transiting Exoplanet Surveying Satellite followed by the scheduled launch of the James Webb Space Telescope in 2018 as well as the planned Wide Field Infrared Survey Telescope. It is hoped that the launch of these upcoming telescopes will pave the way and lead to the new discovery and characterization of possible planets orbiting the distant stars and lay the foundation for future space missions in the search to find a new planet similar to Earth.
Since NASA's launch of the Kepler Space Telescope in 2009 and the discovery of over 5,000 possible exoplanets 1700 of which have been confirmed, the knowledge previously held by astronomers about exoplanets has changed so considerably that today scientists estimate that there are billions of planets existing within our galaxy. Further discoveries have additionally shown that most planets within at least one astronomical unit are at least three times smaller than the diameter of the planet Earth. Astronomers using the Kepler Space Telescope for the first time ever were able to discover an Earth-size planet in orbit in what is characterized as the "habitable zone" of a star, often referred to as an area where water can be formed on a planet's surface.
Over the last decade mankind has discovered several rocky Earth-like planets which are considerably much larger than Earth. However finding smaller planets such as the Earth twins, is much more of a difficult challenge due to the faint signals which are produced by those planets to allow imaging. Due to this the limitation, new technology used to detect and image these Earth-like planets is constantly being developed for use on future space telescopes such seen in the planned James Webb Space Telescope. And although mankind's ability to discover an alien life form may still be quite a few years away, the quest is nonetheless underway.
Searching for a new planer like Earth is much like looking for a needle within a universe based haystack. And yet astronomers today have discovered a planet roughly about the size of the planet Earth which might actually be habitable.
This newly discovered planet which has been appointed Kepler-186f, is more than four-hundred light years away. And although this distance is considerably a far way off, when you look at the facts surrounding mankind's space exploration, nothing has ever come this close.
Kepler-186f is the first conclusive Earth-sized planet discovered within the habitable zone of another star and as such is considered as a fulfillment of one of the primary goals for the Kepler Space Telescope since it's launch in 2009. As not only does this discovery corroborate the existence of a new planet much like Earth, but this discovery will undoubtedly shape the future for further space exploration of exoplanets which may contain sublunary surface environments much like the planet Earth.
Shortly after discovering Kepler-186f NASA scientists began immediately looking for possible signs of emissions which could suggest existence of ETs, but to date no such emissions have been recognized. The planet Kepler-186f is estimated as at about 10% larger than the planet Earth orbiting its nearest star at an unknown distance. Nonetheless astronomers firmly believe that the planet may offer some hope in the quest to find a planet which is able to sustain life as we know it.
Of the almost 1,700 confirmed exoplanets, about 20 have been found to orbit stars within "habitable zones". Following the launch of the Kepler Space Telescope in 2009 NASA in 2011 announced that Kepler had observed five planets which are approximately the same size of Earth, all located within the habitable zone. However these planets are much larger than the planet Earth and to date their true characteristics whether they are gaseous or rocky is still unknown. Based on the Kepler Space Telescope observation of the nebulous light from Kepler-186f scientists estimate that the planet is about the same size as the planet Earth and using hypothetically based models on the planet scientists have theorized that Kepler-186f may be composed of ice, iron and water much like the planet Earth.
Some astronomers have concluded that regardless of the possibility of Kepler-186f consisting of a rocky surface, is by no means a confirmation that the planet is in fact habitable, as that fact would be dependent on the atmospheric conditions existing on the planet, and the truth of it is; our current technology does not allow us to know what those conditions are. However the James Webb Space Telescope which is scheduled for launch in 2018 will likely be able to observe and collect the necessary data about the planet's atmosphere, the M-dwarf star orbited as well as other planets to determine Kepler-186f as a hospitable planet.
Astronomers today are even more committed to observing dwarf stars due to their habitable planets being more easily detectable, as well as to the fact that they are the most abundant type of stars found within our galaxy.
Undoubtedly for astronomers, the discovery of the planet Kepler-186f is much like the beginning of a whole new era in space exploration and although considered as a first, it is a record which begs to be surpassed as scientists strive to discover new planets much like planet Earth where one day we will be able to call our new home.