Number of exoplanetary systems discovered
Pro Research Analysisby 
Searched over 200M research papers
Growth in the Number of Discovered Exoplanetary Systems
Over the past few decades, the number of discovered exoplanetary systems has grown rapidly. As of early 2023, more than 3,800 exoplanetary systems have been identified, marking a significant milestone in the search for worlds beyond our solar system . Earlier in the field, over 100 exoplanets had been catalogued by 2018, showing the exponential increase in discoveries as detection methods improved . By 2019, the number of confirmed exoplanets was approaching 4,000, with most of these planets found orbiting stars of spectral classes F, G, K, and M .
Exoplanet Discovery Methods and Catalogs
The majority of exoplanets have been discovered using the Radial Velocity and Transit methods, with missions like NASA’s Kepler playing a crucial role. The Kepler Mission alone identified over 3,500 transiting exoplanets in its first three years, including about 100 in the habitable zone . The mission also revealed that planets are common in our galaxy, especially small planets . In the first two years of Kepler data, more than 2,500 exoplanet candidates were found, with about 40% in multi-planet systems. This led to the validation of 340 planetary systems containing 851 planets, nearly doubling the number of verified exoplanets at that time .
Multiple and Complex Exoplanetary Systems
A significant portion of exoplanets are found in systems with multiple planets. Studies show that about 80% of close-in, low-mass exoplanets are part of multi-planet systems . Some systems are even more complex, with catalogs identifying around 30 triple-star systems and up to three quadruple-star systems hosting exoplanets, totaling close to 40 planets in these higher-order systems as of July 2022 . The most populated exoplanetary system known to date contains at least seven planets, demonstrating the diversity and complexity of planetary system architectures .
Statistical Patterns and Predictions
Statistical analyses reveal that most exoplanetary systems are found around G-type stars, and many systems exhibit regular spacing between planets, sometimes following patterns similar to the Titius–Bode law 7810. In a study of 229 multi-planetary systems, it was found that about 53% adhere to a logarithmic spacing relation better than our own solar system, and predictions suggest the presence of hundreds of additional, yet-undiscovered exoplanets in these systems .
Conclusion
The number of discovered exoplanetary systems has surged to several thousand, with ongoing missions and improved detection methods continually expanding our catalog. Most exoplanets are found in multi-planet systems, and complex arrangements such as triple and quadruple star systems have also been identified. As technology advances, the number and diversity of known exoplanetary systems are expected to grow, deepening our understanding of planetary formation and the potential for habitable worlds beyond our solar system 1246+3 MORE.
Sources and full results
Most relevant research papers on this topic