The force per unit area equals the ambient mass-density of air times the square of the object’s speed. When a supersonic meteor moves through air, it is subject to a friction force on its frontal surface area. Its measured direction of motion can then be used to calculate the altitude of the three flashes in the explosion and the ambient density of air where they occurred. Given the observed meteor speed of 44 kilometers per second and the explosion energy, one can infer that it was about half a meter in size. The interstellar object disintegrated into a fireball at an altitude of 18.7 kilometers off the coast of Papua New Guinea, resulting in an unusual light curve with three flashes separated from each other by about a tenth of a second. The total energy released was about two percent of the energy in the atomic bomb that exploded over Hiroshima. Given its estimated radiative efficiency of 7%, the total explosion power peaked at 4 terawatt, about a quarter of the global consumption by the world’s population. The meteor fireball produced 31 billion Joules of light with a peak luminosity of nearly 0.3 terawatt. The recent bolide agreement also grants NASA access to light curve data.Ĭonsequently, the letter was supplemented by data on the light curve of CNEOS. NASA acknowledged that it had fallen behind in its asteroid-tracking efforts and would need Pentagon resources to carry out its planetary defense mission. In 2020 a new agreement was signed between the Space Command and NASA, stemming from NASA’s congressional mandate from 2005 to detect nearly all asteroids that could threaten the earth. They constitute a missile warning system that monitors objects in the Earth’s atmosphere for national security purposes. In order to reach such definitive conclusions, the government employs a wide range of classified sensors both on the ground and in space. With the release of the confirmation letter, the government advances scientific knowledge by confirming the interstellar origin of this so-called CNEOS- meteor at the 99.999% confidence. The meteor paper was initially doubted because the uncertainties in the velocity measurements were classified. The meteor detection on Janupredated the first reported interstellar object, `Oumuamua, by almost four years and should be recognized as the first massive interstellar object ever discovered. On April 6, 2022, the United States Space Command tweeted a formal letter to NASA confirming that a meteor identifiedin the CNEOS catalog by my student Amir Siraj and me in 2019 as originating from outside the Solar system based on its high speed, is indeed interstellar.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |