The Cassini spacecraft has carried out one of its closest ever flybys of the gas giant Saturn marking the start of the probe’s final mission.
The NASA probe is nearing the end of its life around Saturn, but before it makes its fatal journey into the planet’s atmosphere it will conduct five of these incredibly close flybys giving the scientific community a never-before-seen glimpse at the planet.
According to the BBC Cassini’s first flyby took place on Monday where it skimmed over the planet’s cloud tops at a distance of just 1,000km.
This ultra-close pass allowed the probe’s detectors to directly sample the gasses found in the planet’s upper atmosphere.
The team should then receive the data in around a week’s time when the probe is scheduled to get back in contact.
If all goes well with the mission the team will be able to push the boundaries even further and take Cassini directly into the planet’s atmosphere.
It is at this point that the mission will enter the realms of the unknown. Cassini will need to fire its thrusters in order to stop itself from getting pulled down. While they know that turbulence will be a problem Cassini’s currently flight plan should be able to cope with it.
One of the big mysteries the team is hoping to solve is the simple question of just how long a day is on Saturn.
That might sounds easy enough but so far a definitive answer has eluded scientists.
In an earlier dive past the planet researchers were able to establish that Saturn’s magnetic field has almost no tilt, a fact that is at odds with our current understanding of how a planet’s magnetic field is generated in the first place.
“The tilt seems to be much smaller than we had previously estimated and quite challenging to explain,” said Michele Dougherty, Cassini magnetometer investigation lead at Imperial College, London. “We have not been able to resolve the length of day at Saturn so far, but we’re still working on it.”
Even a slight tilt would have helped make the daily wobble of the planet’s interior visible to researchers, thus allowing them to create a precise measurement for a single day.
With no tilt there comes no measurement so the hope is that these subsequent deeper dives will be able to provide some answers once and for all.
Cassini, launched in 1997, will continue making these ultra-close flybys of the planet until 15 September upon which the spacecraft will make its final, fatal descent down into the planet’s atmosphere.