SPACE | NASA's Cassini spacecraft to face fiery end

Posted September 15, 2017

NASA/JPL-Caltech/Space Science Institute The Cassini space probe took this image of geysers on the Saturn moon Enceladus shooting 50 miles into space. "To go to Saturn and come away having discovered what we think might be the best place in the solar system to go to search for life".

Another gem from Cassini was the series of observations that led to this iconic moving portrait of Saturn's great hexagonal polar storm. The mission team behind Cassini has planned to send the spacecraft into Saturn for many years now, in order to protect the planetary system the vehicle has been exploring.

The download of Cassini's last pictures, which began around 5:45 p.m. EDT on Thursday, should take about 11 hours to finish.

As Cassini hurtles on towards its death, the program head at NASA - Curt Niebur - is philosophical about the probe's final fate.

The mission's planners knew Cassini would eventually run so low on fuel it would be impossible to control the ship.

Other potential discoveries will require researchers to put together all of Cassini's data sets from all of its instruments over its entire 13-year study of Saturn. But "the propellant tanks will explode eventually as the temperatures get high enough", he says.

Cassini also gave us our closest-ever views of Saturn's most interesting features, like its northern polar hexagon, its incredibly thin rings and its atmosphere. About two minutes later, Cassini will burn and disintegrate completely - any traces of it will melt due to the heat and high pressure of the giant planet's hostile atmosphere, she added. This time will be considered the end of his mission, although it really is going to happen 86 minutes earlier, so much needs to signal from ship reached Land.

Maize said there was the option to send Cassini out of orbit around Saturn entirely, but the scientific return promised by a final plunge into the planet was too good to refuse. Once they are firing at full capacity, the thrusters can do no more to keep Cassini stably pointed, and the spacecraft will begin to tumble.

In all, Cassini collected more than 453,000 images and traveled 4.9 billion miles (7.9 billion kilometres).

Intrigued by Cassini's discoveries, scientists have submitted concepts for future "spacecraft to drift on the methane seas of Titan and fly through the Enceladus plume to collect and analyze samples for signs of biology" that are under consideration, according to NASA. Just a few hours before it entered Saturn's atmosphere, the mission team made Cassini roll a bit, positioning the vehicle's instruments toward the planet while pointing its radio antenna at Earth.

APL built one of MIMI's three sensors-the Ion and Neutral Camera, or INCA-which produced the first-ever images of a planet's magnetosphere using an APL-developed technique known as energetic neutral atom imaging. Objective since it was of major scientific discoveries on our understanding of Saturn as the solar system, and since it was still in great shape, it has been extended to nine years.

Enceladus is Saturn's sixth-largest moon and is mostly covered by fresh water ice.

"We didn't have any choice", Maize said in an interview shortly before the end of the mission, when asked why the mission ended with a plunge into the atmosphere.

Scientists found deep, liquid-filled canyons on Saturns moon Titan for the first time. The communications link with the spacecraft is continuous from now through the end of mission.