NASA's Cassini spacecraft has captured pictures in which scientists have found 101 geysers connected to a subsurface ocean on Saturn's moon Enceladus. Scientists believe that it is possible for these geysers to bring liquid water to the moon's icy surface. This is significant, because the presence of liquid water is one of the things scientists look for when identifying planets that might be suited for carbon-based life forms.
Two new articles that go over these findings were published online in the Astronomical Journal.
The Cassini-Huygens spacecraft reached Saturn and its moons in 2004. According to the NASA website, it is one of the most ambitious missions ever launched into space. The Cassini spacecraft spent seven years watching the moon Enceladus. From the pictures, scientists have been able to identify 101 geysers. They also have discovered that every geyser is located on a hot spot on the moon. From that data, scientists extrapolated that all of the geysers are connected to the same subterranean ocean.
Scientists have been aware of the geysers since 2005, but have struggled to understand their behavior patterns. One theory was that friction created by fractures in the surface of Enceladus created the heat necessary to form the geysers and melt the ice into liquid water.
Now, scientists have used triangulation to locate the surface locations of the geysers. They found that the moon was hottest underneath the geysers. However, they still didn't know which had caused which: if the geysers had created the heat, or if something hot had created the geysers.
In 2010, scientists had the answer. They found using data collected by Cassini that small geysers were found on top of small hot spots, which were too small to have been created by the frictional heat that was earlier theorized.
Carolyn Porco, the leader of the Cassini imaging team from the Space Science Institute in Boulder, Colorado, who was the lead author of the first research paper, said, "Once we had these results in hand, we knew right away heat was not causing the geysers, but vice versa. It also told us the geysers are not a near-surface phenomenon, but have much deeper roots."
Because of this data, the authors of the research paper believe that the only explanation for the formation of the geysers was a sea beneath the icy surface of the moon. The research also showed paths through the icy exterior of Enceladus that could bring liquid water to the surface if filled with water.
