In a true milestone for the history of space exploration, the National Aeronautics and Space Administration (NASA) confirmed the discovery of 6000 exoplanets.
This achievement, the result of three decades of global scientific work, marks a significant advance in our understanding of the universe. All of them are outside our galaxy.
What are exoplanets?
According to NASA, exoplanets are planets that are outside of our Solar System. The first of them, orbiting a star similar to our Sun, was discovered in 1995.
Since then, the pace of discoveries has accelerated notably. In fact, just in the last two years, the number increased from 5000 to 6000.
Most of these planets are discovered using the transit method, which detects the slight decrease in brightness of a star when a planet passes in front of it. On the other hand, only a small fraction of exoplanets have been able to be directly photographed.
How discoveries are validated
The validation process is rigorous. For an exoplanet to be officially confirmed, astronomers conduct follow-up observations with specialized telescopes. NASA, through its Exoplanet Science Institute (NExScI), maintains constant monitoring.
This process is crucial to rule out false positives, which is why there are more than 8000 possible exoplanets waiting for a definitive confirmation.
Key instruments like the Kepler Space Telescope and the TESS satellite (Transiting Exoplanet Survey Satellite) were fundamental for these discoveries. The space agency has already announced that future missions, such as those of the Nancy Grace Roman Space Telescope, will continue to provide vital data.
The importance of this discovery
According to Dawn Gelino from NASA’s Exoplanet Exploration Program, the great diversity of planets found offers crucial information about the necessary conditions for planetary formation.
This helps scientists estimate how common similar planets to Earth could be. The findings exceed initial expectations, with worlds ranging from giant gas giants orbiting very close to their star, to planets that move around dead stars.
Now, as they suggest, one of the core challenges identified by NASA lies in the study of exoplanet atmospheres.
The James Webb Space Telescope has already analyzed the chemical composition of over a hundred exoplanets, although the direct and detailed observation of atmospheres in worlds of the size and temperature of Earth still depends on the development of new technologies.
It is necessary to more efficiently block the brightness of the host star to distinguish the signals of interest in distant and faint planets.
