article_snippet: The first paper, published this week in the journal Nature, relates to microscopic grains of rock detected by Cassini in the Saturn system.
article_snippet: Cassini's cosmic dust analyzer (CDA) instrument repeatedly detected miniscule rock particles rich in silicon, even before Cassini entered Saturn's orbit in 2004.
article_snippet: The consistent size of the grains observed by Cassini, the largest of which were 6 to 9 nanometers, was the clue that told the researchers a specific process likely was responsible.
article_snippet: We methodically searched for alternate explanations for the nanosilica grains, but every new result pointed to a single, most likely origin,' said co-author Frank Postberg, a Cassini CDA team scientist at Heidelberg University in Germany.
article_snippet: The Japanese team, led by Yasuhito Sekine, verified the conditions under which silica grains form at the same size Cassini detected.
article_snippet: The researchers think the conditions under which silica grains form at the same size Cassini detected may exist on the seafloor of Enceladus, where hot water from the interior meets the relatively cold water at the ocean bottom.
article_snippet: Bouquet worked with co-author Hunter Waite, who leads Cassini.
highlights_snippet: Cassini team last year said Cassini team could be bigger than Lake Superior .