Illustration of brown dwarf OGLE-2015-BLG-1319. Brown dwarfs weigh somewhere between our solar system's most massive planet (Jupiter) and the least-massive-known star. Brown dwarfs are not massive enough to sustain nuclear fusion of hydrogen to helium in their cores. This brown dwarf interests astronomers because it may fall in the desert of brown dwarfs. It has been found that, for stars roughly the mass of our Sun, less than 1 per cent have a brown dwarf orbiting within 3 AU (astronomical units, 1 AU is the distance between Earth and the Sun). This brown dwarf was discovered when it and its star passed between Earth and a much more distant star in our galaxy. This created a microlensing event, where the gravity of the system amplified the light of the background star over the course of several weeks. This microlensing was the first to be seen by two space-based telescopes: NASA's Spitzer and Swift missions. | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / R. Hurt (Caltech-IPAC) / JPL-Caltech / NASA |
Taille de l’image : | 5573 px × 3135 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |