Cassini’s final image of Saturn’s ‘yin and yang’ moon

The Cassini spacecraft may be gone, but the remarkable observations gathered over the craft’s 13-year mission will continue to reveal new insights on Saturn and the mysterious worlds orbiting it for some time to come.

Just days after the dramatic conclusion to the craft’s mission, NASA has released a stunning new observation of the planet’s ‘yin-and-yang moon,’ Iapetus.

The photo is one of Cassini’s last looks at the 914-mile-wide moon, revealing the striking dichotomy of its surface, long known to be bright on one side and dark on the other.

The strange moon is Saturn’s third-largest satellite.

This false-color ‘farewell’ view combines individual frames captured with filters sensitive to ultraviolet, green, and infrared light, according to NASA, and looks toward the Saturn-facing hemisphere of Iapetus.

For centuries, scientists have questioned Iapetus’ unusual ‘yin-yang’ appearance.

But, thanks to Cassini, they may have solved the mystery of its contrasted surface.

‘Cassini observations of Iapetus support the prevailing theory that led to the understanding that the dichotomy of the surface is due to a combination of infalling dust from outside of the moon followed by a migration of water ice from the darker (therefore warmer) areas to the cold, brighter surfaces,’ NASA explains.

Cassini captured this last look at Iapetus on May 30, from roughly 1.5 million miles away. 

NASA’s Cassini mission came to a ‘bittersweet’ conclusion early Friday morning, as the historic spacecraft plunged into Saturn’s atmosphere to become one with the gas giant planet it had studied for 13 years.

As mission scientists said their farewells to the craft and prepare to examine its final observations, footage emerged of the dramatic moment Cassini first lifted off 20 years ago, to embark on its ‘billion mile trek to Saturn.’

The breathtaking footage takes us back to the Cape Canaveral launchpad on October 15, 1997, as mission control counts down to the start of a journey that brought an ‘incredible wealth of discoveries.’ 

As mission scientists say their farewells to the craft and prepare to examine its final observations, footage has emerged of the dramatic moment Cassini first lifted off 20 years ago, to embark on its ‘billion mile trek to Saturn’

Cassini launched in 1997 from Cape Canaveral Air Force Station in Florida, bringing it past Venus (twice), Earth, and Jupiter on its way to Saturn.

But, it would be many years – and a billion miles – before it reached its target.

‘We have cleared the tower, and the Cassini spacecraft is on its way to Saturn,’ mission control can be heard saying in the 20-year-old footage, as the rocket breaks through the clouds.

The spacecraft arrived to Saturn in 2004, marking the start of its historic 13-year mission studying the planet and its moons.

‘This is the final chapter of an amazing mission, but it’s also a new beginning,’ Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate at NASA Headquarters in Washington, said as the space agency marked the end of Cassini’s mission.

‘Cassini’s discovery of ocean worlds at Titan and Enceladus changed everything, shaking our views to the core about surprising places to search for potential life beyond Earth.’

After 20 years in space, Cassini spacecraft finally completed its suicide mission at 7:56 a.m. (ET) Friday, plunging into Saturn’s atmosphere.

While we were unable to see Cassini’s dying moments, an animation released by NASA reconstructs the probe’s last few minutes as it tumbled through Saturn’s atmosphere at 77,000mph

Cassini launched in 1997 from Cape Canaveral Air Force Station in Florida, bringing it past Venus (twice), Earth, and Jupiter on its way to Saturn. But, it would be many years – and a billion miles – before it reached its target

‘We have cleared the tower, and the Cassini spacecraft is on its way to Saturn,’ mission control can be heard saying in the 20-year-old footage, as the rocket breaks through the clouds

‘The Cassini operations team did an absolutely stellar job guiding the spacecraft to its noble end,’ said Earl Maize, Cassini project manager at JPL.

‘From designing the trajectory seven years ago, to navigating through the 22 nail-biting plunges between Saturn and its rings, this is a crack shot group of scientists and engineers that scripted a fitting end to a great mission.

‘What a way to go. Truly a blaze of glory.’

The confirmation of the mission was received at Nasa’s Jet Propulsion unit at 07:56 EST (12:56 BST).

Upon receiving the news, Earl Maize, program manager for Cassini, announced: ‘The signal from the spacecraft has gone. Congratulations, this has been an incredible mission and incredible spacecraft.’  

After 20 years in space, Nasa’s Cassini spacecraft has finally completed its suicide mission, plunging into Saturn’s atmosphere. The confirmation of the mission was received at Nasa’s Jet Propulsion unit at 07:56 EST (12:56 BST)

In its thirteen years at Saturn and two decades in space, the $4 billion (£3 billion) Cassini probe has transformed our understanding of the ringed planet and its moons.

It has watched giant storms on the gas giant, recorded its ring system in stunning detail, and revealed incredible new insights on the potential habitability of Saturn’s moons.

The decision to kill off Cassini was taken because the craft would soon run out of fuel and become impossible to steer. Scientists feared a collision with Titan or Enceladus – two of Saturn’s moons that in the past 10 years have shown a potential to host simple life.  

Nasa’s animation imagine what the ‘death dive’ would have looked like 

First, they expect the probe to have shed layers of insulating material. 

 Nasa’s animation imagines what the ‘death dive’ would have looked like. First, they expect the probe to have shed layers of insulating material

Then its large external structures, including the 11ft wide dish antenna and 30ft long magnetometer boom will have weakened and broken apart, followed by other body-mounted components, and eventually the leading face of the space craft itself.

It is also possible that propellant left in Cassini’s fuel tanks may have exploded.

Meanwhile, atmospheric friction will have sent temperatures soaring. 

By the time what was left of Cassini reached the cloud tops it would have been transformed into a glowing fragmenting meteor, hotter than the surface of the sun.

Finally, intense heat and pressure would have caused every part of the space craft to melt and dissociate, scattering its atoms to the winds of Saturn.

Then its large external structures, including the 11ft wide dish antenna and 30ft long magnetometer boom, will have weakened and broken apart

 This would be followed by other body-mounted components, and eventually the leading face of the space craft itself

Meanwhile, atmospheric friction will have sent temperatures soaring.

By the time what was left of Cassini reached the cloud tops it would have been transformed into a glowing fragmenting meteor, hotter than the surface of the sun.

Finally, intense heat and pressure would have caused every part of the space craft to melt and dissociate, scattering its atoms to the winds of Saturn.

Cassini’s death plunge was the climax of a ‘grand finale’ that saw the probe slip between Saturn and its rings in 22 daring orbits.

Fifteen minutes before the end, the voice of Dr Maize could be heard in a live stream from mission control telling his team: ‘This might be a good time to pass out the farewell peanuts.’

Earlier Jet Propulsion Laboratory director Mike Watkins told a Nasa interviewer: ‘It’s kind of a bitter-sweet event for all of us.

‘For me personally, it’s more sweet than bitter, because Cassini has been such a fantastic mission.

During the live feed, experts from Nasa described the event as ‘the last hour of the last chapter of Cassini’s Grand Finale.’  

The confirmation of Cassini’s death was at 07:56 EST (12:56 BST), when Mr Maize said: ‘The signal from the spacecraft has gone. Congratulations, this has been an incredible mission and incredible spacecraft’

Project manager Earl Maize, centre, shakes hands with Bill Heventhal (left) head of Uplink Operations in mission control at Nasa’s Jet Propulsion Lab

Cassini science team members Nora Alonge (R), Scott Edgington (C) and Jo Pitesky (L) hug as the final loss of signal from the Cassini spacecraft is confirmed

With just 10 minutes to go before the expected loss of signal, the live feed turned its attention to the control room, where it could be seen that Cassini was travelling at around 75,000 mph.

At this point, Cassini only had one per cent of its fuel sources left. But the radio loss depended on how much of a fight Cassini’s thrusters put up against Saturn’s atmosphere

Cassini burned up like a meteor 83 minutes before the signal died as it dove through Saturn’s atmosphere, becoming one with the giant gas planet it set out in 1997 to explore.

But it took that long for the news to arrive at Earth a billion miles away.

The only spacecraft to ever orbit Saturn, Cassini showed us the planet, its rings and moons up close in all their glory. 

Perhaps most tantalizing, ocean worlds were unveiled by Cassini and its hitchhiking companion, the Huygens lander, on the moons Enceladus and Titan, which could possibly harbor life.

Cassini snapped its ‘last memento photos’ of the Saturn system Thursday. 

Dutiful to the end, the spacecraft sampled Saturn’s atmosphere Friday morning as it made its final plunge. 

Flight controllers wearing matching purple shirts stood and embraced and shook hands.

More than 1,500 people, many of them past and present team members, had gathered at California’s Jet Propulsion Laboratory for what was described as both a vigil and celebration. 

Even more congregated at nearby California Institute of Technology, which runs the lab for NASA.

Project scientist Linda Spilker noted Cassini has been running ‘a marathon of scientific discovery’ for 13 years at Saturn. 

Saturn’s active, ocean-bearing moon Enceladus sinks behind the giant planet in a farewell animation from NASA’s Cassini spacecraft

Members of staff who have worked on the project were very tearful upon hearing the news that Cassini had completed its suicide mission

With just 10 minutes to go before the expected loss of signal, the live feed turned its attention to the control room, where it could be seen that Cassini was travelling at around 75,000 miles/hour

Engineer Mar Vaquero monitored the status of Cassini spacecraft as it entered the atmosphere of Saturn in mission control at JPL

IO manager Luis Morales monitors the status of Cassini in its final moments

When asked about Cassini’s fate, Earl Maize, program manager for Cassini, said: ‘Cassini’s fate has been sealed. There’s absolutely nothing else we can do. At 4:55am [12:55 BST], we’ll be entering Saturn’s atmosphere. Cassini won’t notice Saturn until the last 90 seconds. Then it will lose the battle, and become totally vapourised’ 

‘So we’re here today to cheer as Cassini finishes that race,’ she said.

The spacecraft tumbled out of control while plummeting into Saturn’s atmosphere.

Project officials invited ground telescopes to look for Cassini’s last-gasp flash, but weren’t hopeful it would be spotted from a billion miles away.

Cassini has begun transmitting the final images of its mission, revealing a last look at Saturn and its rings before the spacecraft plunges into the planet’s atmosphere. This image was captured on September 13

This is believed to be the final image taken by Cassini. The camera was pointing towards Saturn, and the image was taken using the CL1 and CL2 filters. It was taken at 12:59 EST (19:59 BST) yesterday, and recieved by Nasa at 02:03 EST (07:03 BST) this morning

At around 07:54 EST (11:54 BST) , Cassini will dive into Saturn’s atmosphere travelling at a speed of roughly 70,000 miles per hour, before sending out a final signal that will radiate across the solar system ‘like an echo.’ The image above is one of its last ever, taken on September 13

This Grand Finale, as NASA calls it, came about as Cassini’s fuel tank started getting low after 13 years exploring the planet. 

Scientists wanted to prevent Cassini from crashing into Enceladus or Titan – and contaminating those pristine worlds. 

And so in April, Cassini was directed into the previously unexplored gap between Saturn’s cloud tops and the rings. Twenty-two times, Cassini entered the gap and came out again. The last time was last week.

The leader of Cassini’s imaging team, Carolyn Porco, a visiting scholar at the University of California, Berkeley, was so involved with the mission for so long that now, ‘I consider it the start of life, part two.’

Cassini departed Earth in 1997 and arrived at the solar system’s second largest planet in 2004. The European Huygens landed on big moon Titan in 2005. Nothing from Earth has landed farther.

In all, Cassini collected more than 453,000 images and traveled 4.9 billion miles. It was an international endeavor, with 27 nations taking part. The final price tag was $3.9 billion.

Talking about seeing the first images that were received from Cassini it 2004, Dr Maize said: ‘Thinking about them still gives me goosebumps now.’

According to NASA, Cassini used its visual and infrared mapping spectrometer (VIMS) to observe the impact site, which was, at the time, on Saturn’s night side. Then, it was lit only by light reflected from the planet’s massive rings. This image shows a last look at the icy moon Enceladus, thought to contain the ingredients to support microbial life

If all is according to schedule, the spacecraft captured its final image of the mission at 12:58 EST (17:58 BST) yesterday, revealing the location at which it will make its fateful entry

TIMELINE FOR THE DEATH OF CASSINI

September 12, 21:19 ET (02:19 BST), Earth started receiving Cassini’s last data on Titan.

September 14, 15:58 ET (20:58 BST), Cassini’s cameras took their last pictures.

September 14, 16:22 ET (21:22 BST), Cassini’s last batch of data—including those last pictures—began streaming back to Earth. 

At 7:55 a.m. EDT (4:55 a.m. PDT) on Friday, it will lose contact with mission operators following its entry into Saturn’s harsh atmosphere. The graphic above shows the relative altitudes of Cassini’s final five passes through Saturn’s upper atmosphere, compared to the depth it reaches upon loss of communication with Earth

September 15, 03:14 ET (08:14 BST), The spacecraft rolled into position to collect atmospheric data during the descent.

September 15, 06:31 ET (11:31 BST), Cassini entered Saturn’s atmosphere.

September 15, 06:32 ET (11:32 BST), Cassini’s antenna pointed away from Earth, leading to a loss of signal. Shortly afterwards, the spacecraft vaporized.

September 15, 07:00-08:30 ET (11:00-12:30 BST), NASA livestreamed the scene at mission control at NASA JPL, with live commentary about the end of the mission.

September 15, 07:55 ET (11:55 BST), Earth will register the loss of signal, indicating the end of Cassini.

NASA’s Cassini probe is counting its final hours before one last plunge into Saturn that will cap a fruitful 13-year mission that greatly expanded knowledge about the gas giant. The spacecraft is on its last approach to the gas giant planet after mission navigators confirmed that it’s on course for its ‘death dive’

The spacecraft is now just hours away from its planned demise, after 13 years of groundbreaking discoveries at the ringed planet

The space agency has begun releasing the raw, unprocessed images as Cassini prepares for its ‘death dive.’ The images have finally started to arrive to Earth

The spacecraft began its final approach to Saturn on Wednesday, after mission navigators confirmed it was on course for its entry into the planet’s atmosphere. This image shows one of its last looks at the moon Titan, captured on Sept 13

Cassini has begun transmitting the final images of its mission, revealing a last look at Saturn and its rings before the spacecraft plunges into the planet’s atmosphere. This photo was captured on Sept 13

In 13 years studying Saturn, Cassini has made countless groundbreaking observations. Here, it looks at Saturn’s rings one last time before diving into the atmosphere

Cassini flew by Titan one last time on Tuesday before transmitting images and scientific data from the flight. This unprocessed image of Titan was taken by NASA’s Cassini spacecraft during the mission’s final, distant flyby on Sept. 11, 2017