Astronomers have confirmed and are closing the tally of alien planets into 1,000 just two decades following the discovery of the first world beyond the ones found in our solar system.
According to four of the five databases that document exoplanet discoveries, there are 900 confirmed alien planets, and two of them peg that the total number as of Sept. 26 is 986. But the rest of the planets including the 1,000th exoplanet will be announced in a matter of days or weeks.
Space.com reported that this progression on otherworldly discovery, which began in 1992, is undeniable. Back then, researchers have only detected two exoplanets orbiting a rotating neutron star (pulsar) about 1,000 light-years from the Earth. Nevertheless, it was three years after, in 1995, when the presence of an alien world orbiting a "normal" star similar to the sun, was confirmed.
Based on several studies, NASA's Kepler space telescope is projected to be the medium that will help identify and determine more alien planets in the future. As a matter of fact, the said telescope paved the way to the discovery of many exoplanets before it was hobbled in May of this year, after the second facet of its four orientation-maintaining reaction wheels failed.
As of late, Kepler was able to identify 3,588 planet candidates, but only 151 has been confirmed thus far. Nonetheless, space scientists firmly believe that at least 90 percent of the figure presented will soon enough be confirmed as real exoplanets.
But the said figures are only a tip of the Milky Way galaxy's mysterious planetary iceberg. Many other planets remain undetected, and a team of researchers estimated that the Milky Way star hosts roughly 1.6 worlds. This simply means that in our galaxy alone there might be 160 billion planets, and this only account to worlds with parent stars.
In 2011, a different team proposed that "rogue planets" (those that do not encircle a star) may possibly outnumber "normal" exoplanets by 50 percent more or less.
Throughout the years, diverse planets have been identified. Scientists have identified exoplanets that are light and airy as though they are Styrofoam, and there are others that are as dense as iron. They have also discovered exoplanets that, similar to the planet Earth, are at a right habitable zone or distance from their own suns. These are perceived to be capable of supporting liquid water and perhaps even life as we know it.
According to the Planetary Habitability Lab that keeps track of all the databases, here are the five chief exoplanet-discovery databases and their respective tallies as of recent: "the Extrasolar Planets Encyclopedia (986); the Exoplanets Catalog, run by the University of Puerto Rico at Arecibo's Planetary Habitability Laboratory (986); the NASA Exoplanet Archive (905); the Exoplanet Orbit Database (732); and the Open Exoplanet Catalog (948)."
