In June, exoplanet science reached a milestone with an astounding 4,000 planets discovered beyond our solar system. That’s a big leap forward considering the first confirmed detection of a world beyond our own star system only occurred in 1992.
1992 First Exoplanet Discovery
On January 9, 1992, the Arecibo Observatory in Puerto Rico located two exoplanets orbiting a pulsar (PSR B1257+12) in the Virgo constellation roughly 2,300 light-years distant from Earth. A pulsar is basically a rapidly rotating neutron star, with the planets in its orbit likely lit up with light from auroras similar to our own Northern Lights.
An exoplanet (51 Pegasi b) orbiting a main-sequence star (51 Pegasi) similar to our own sun was subsequently discovered in 1995, located around 50 light-years away in the Pegasus constellation. Since then, alien worlds have kept popping up with great regularity as we refine our view of the Universe.
4,000+ Exoplanets Discovered
The four thousandth exoplanet milestone was reached in June. NASA marked the occasion by releasing a video depicting all the exoplanets discovered within the entire night sky. Check out the video below, with the giant U shape seen representing the central band of our Milky Way galaxy. The experience is a moving one, watching these new previously undiscovered celestial worlds blinking into our observed existence.
Kepler and Other Space Telescope
The Kepler Space Telescope is credited with the discovery of most of these exoplanets. In March 7, 2009, the telescope was launched in Earth’s orbit, and over its nine and a half years of operation subsequently detected 2,662 exoplanets.
Kepler has since been decommissioned, but other projects have been filling Kepler’s shoes. This includes NASA’s Transiting Exoplanet Survey Satellite (TESS), which has found over 700 new exoplanets. Future projects also include the European Characterizing Exoplanets Satellite (CHEOPS) set to launch this year, and NASA’s James Webb Space Telescope which has a blast off date set for 2021. Furthermore, both space telescopes will also have the capability to determine if any exoplanets found have the necessary conditions to support extraterrestrial life.
More Exoplanets Discovered
According to the NASA, 4,016 exoplanets have now been discovered as of July 13. That includes an additional seven exoplanets being added to the archive on July 11th. You can keep abreast of the all the latest exoplanet news and discoveries by checking out the NASA Exoplanet Archive. There should be plenty to keep track of, too.
After all, the Milky Way has an estimated 200 billion stars, meaning there are potentially more than 11 billion habitable Earth-sized planets waiting to be discovered in our galaxy alone. That figure could rise to more than 40 billion exoplanets if alien worlds orbiting red dwarfs, the most common type of star in our Milky Way, are included.