Cosmic Collisions: How to Witness the Birth of Planets ⚡ экспресс
Giant impacts — collisions of planet-sized bodies — were modeled using the SWIFT hydrodynamic code for colliding masses from 0.2 to 4 Earth masses. After the impact, the position of the photosphere was determined, allowing the initial luminosity of the remnants to be calculated, ranging from 5×10⁻⁵ to 10⁻¹ solar luminosities. The luminosity decay was approximately exponential with a characteristic time from 1 to 2000 days. Based on these results and estimates of the frequency of giant impacts, it is established that in the full photometric release of Gaia DR4, between 0 and 14 such events are expected to be registered, and no fewer will be detectable by LSST. Direct observation of collision remnants will allow reliable constraints to be placed on the prevalence of giant impacts in the Galaxy and their role in planet formation.
The birth of planets resembles the workings of a cosmic forge. Rocky blocks collide and fuse together. A powerful impact strikes a spark—material heats to white-hot and glows like cooling metal. Computer simulations show: the flash is visible from days to years, peaking at a tenth of the sun's light. Modern telescopes monitoring millions of stars can catch it. New sky surveys like Gaia and LSST will gather precise brightness data of stars. Scientists anticipate up to 14 such events—they will reveal how often worlds collide in the Milky Way.
🎯 The temperature at the impact site skyrockets to thousands of degrees in minutes—debris glows like a blacksmith's workpiece.
🎬 In Lars von Trier’s film ‘Melancholia,’ Earth collides with a rogue planet, producing a blinding flash akin to this effect.