A 6.7 meter Cassini probe which has been exploring Saturn for 13 years found a vast void between the planet's iconic rings as it became the first spacecraft to venture between Saturn and its rings.
The 20-year-old joint mission of NASA, the European Space Agency, and the Italian Space Agency made the first pass to explore what lies between the rings in late April and the second one on May 2.
The unmanned Cassini spacecraft, after completing two passes in the vast, unexplored area between Saturn's rings has discovered not much else there, researchers at NASA said.
"The region between the rings and Saturn is 'the big empty' apparently," said Cassini Project Manager Earl Maize of NASA's Jet Propulsion Laboratory in Pasadena, California, after the probe's first pass.
Scientists have been surprised to find that not all that much, not even space dust, lies between Saturn's rings.
The rings themselves are made of fast-moving particles of ice and space debris.
The gap between the rings and the top of Saturn's atmosphere is about 2,400 kilometers.
Cassini is expected to make a total of 22 dives between the rings and the planet before making a death plunge into the gas giant in September.
The spacecraft launched in 1997 and began orbiting Saturn in 2004.