----------------------------------- valy 18 Aug 2020 13:17 2020 QG a trecut la 3000km de Pamant ----------------------------------- A car-size asteroid flew within 1,830 miles of Earth over the weekend — the closest pass ever — and we didn't see it coming: https://www.businessinsider.com/car-size-asteroid-2020qg-missed-earth-by-2000-miles-2020-8 ----------------------------------- GunDALF 18 Aug 2020 13:19 ----------------------------------- Parca p-ala de la Celiabinsk l-au detectat. Si a fost mult mai mare. ----------------------------------- valy 18 Aug 2020 13:23 ----------------------------------- Au spus ca a venit dinspre soare: "The asteroid approached undetected from the direction of the sun," Paul Chodas, the director of NASA's Center for Near Earth Object Studies, told Business Insider. "We didn't see it coming." ----------------------------------- GunDALF 18 Aug 2020 13:32 ----------------------------------- Detecteaza ei ocultatii ale stelelor de la (mii de) ani lumina, descoperind exoplanete si n-au putut detecta ocultatia Soarelui? :lol: ----------------------------------- valy 18 Aug 2020 13:38 ----------------------------------- Nu zice ca a fost ocultatie. Acum nu stiu cum ii urmaresc, doar vizual sau si radio (radar?). Insa a fost descoperit vizual de https://www.ztf.caltech.edu/ ----------------------------------- MariusP 18 Aug 2020 14:20 ----------------------------------- Parca p-ala de la Celiabinsk l-au detectat. Si a fost mult mai mare.Detecteaza ei ocultatii ale stelelor de la (mii de) ani lumina, descoperind exoplanete si n-au putut detecta ocultatia Soarelui? :lol: Poate din cauza :Detectability Asteroids as small as 2020 QG are difficult to detect because the are small and dim. Between 2010–2019, the asteroid was not brighter than about apparent magnitude 31 making it about 10 thousand times fainter than a more common discovery magnitude of 21. The Hubble Space Telescope needs 3 weeks of exposure time to reach magnitude 31. During the 2020 approach, by the time the asteroid was brighter than magnitude 24, it had a solar elongation of only 60 degrees. After closest approach the asteroid quickly had a solar elongation of 124 degrees. ----------------------------------- GunDALF 18 Aug 2020 14:40 ----------------------------------- E cert ca exista destui nedetectabili. Mai ales de pe Pamant. Probabil ca un observator extern (in spatiu, pe Luna sau combinate) ar avea alta perspectiva asupra vizualizarii lor. Dar cred ca mai e pana atunci. ----------------------------------- valy 18 Aug 2020 15:37 ----------------------------------- Radar: https://www.nasa.gov/vision/universe/solarsystem/asteroid-20061219.html