The spacecraft embarked on the first orbit on Sunday evening, marking a turning point in planetary exploration as Saturn's upper atmosphere has never previously been explored.

The probe's instruments are expected to collect rich scientific data as it makes the dives, potentially revealing how the planet is arranged internally and how much material is contained in its icy rings.

With the first pass still in progress, Cassini will go where no craft has gone before -- reaching as close as 1,010 and 1,060 miles (1,630 and 1,710 kilometers) above the planet's cloud tops.

"It's long been a goal in planetary exploration to send a dedicated probe into the atmosphere of Saturn, and we're laying the groundwork for future exploration with this first foray," Spilker said.

Launched in 1997, Cassini reached Saturn in 2004. The craft revolutionized scientists' knowledge of Saturn, with its first close-up survey of the gas giant.

The craft is now locked into a terminal collision course with the atmosphere of the planet, where it is expected to burn up like a meteor on September 15 at 9:45 a.m. GMT (6:45 a.m. ET).

At this point, contact will be permanently lost and the spacecraft will burn up.

Experts say that allowing Cassini to be destroyed reduces the risk of the probe damaging one of Saturn's moons and impacting future scientific work.

Follow this link:

NASA's Cassini probe dives into Saturn's atmosphere - CNN