the cassini spacecraft arrived at saturn on september 15, 2017.
the cassini spacecraft arrived at saturn on september 15, 2017.
when did the cassini spacecraft arrived at saturn?
september 15, 2017
launched aboard a titan ivb/centaur on october 15, 1997, "cassini" was active in space for nearly 20 years, with 13 years spent orbiting saturn and studying the planet and its system after entering orbit on july 1, 2004. the voyage to saturn included flybys of venus (april 1998 and july 1999), earth (august 1999), the asteroid 2685 masursky, and jupiter (december 2000). the mission ended on september 15, 2017, when "cassini's" trajectory took it into saturn's upper atmosphere and it burned up in order to prevent any risk of contaminating saturn's moons, which might have offered habitable environments to stowaway terrestrial microbes on the spacecraft. the mission is widely perceived to have been successful beyond expectations. nasa's planetary science division director, jim green, described "cassini-huygens" as a "mission of firsts", that has revolutionized human understanding of the saturn system, including its moons and rings, and our understanding of where life might be found in the solar system.
cassini–huygens
lightning activity has been optically detected on jupiter. existence of lightning activity on that planet was predicted by bar-nun [1975] and it is now supported by data from galileo, voyagers 1 and 2, pioneers 10 and 11, and cassini. saturn is also confirmed to have lightning activity. though three visiting spacecraft (pioneer 11 in 1979, voyager 1 in 1980, and voyager 2 in 1981) failed to provide any convincing evidence from optical observations, in july 2012 the cassini spacecraft detected visible lightning flashes, and electromagnetic sensors aboard the spacecraft detected signatures that are characteristic of lightning. little is known about the electrical parameters of the interior of jupiter or saturn. even the question of what should serve as the lower waveguide boundary is a non-trivial one in case of the gaseous planets. there seem to be no works dedicated to schumann resonances on saturn. to date there has been only one attempt to model schumann resonances on jupiter. here, the electrical conductivity profile within the gaseous atmosphere of jupiter was calculated using methods similar to those used to model stellar interiors, and it was pointed out that the same methods could be easily extended to the other gas giants saturn, uranus and neptune. given the intense lightning activity at jupiter, the schumann resonances should be easily detectable with a sensor suitably positioned within the planetary-ionospheric cavity.
schumann resonances