Nasa’s Cassini spacecraft has met its demise as it plunged into Saturn’s atmosphere this morning where it was vaporised within minutes in a meteoric blaze.
The dramatic end of one the space agency’s most successful missions was confirmed at just before 1pm UK time, as the signal from Cassini fell silent for the first time in 13 years.
In its final week, the spacecraft looped between the rings and the planet one last time, past Titan, Saturn’s giant moon, for a farewell fly-by, before diving into Saturn’s atmosphere at 120,000km/h (76,000mph).
As the gases began rushing over the surface of the spacecraft, the craft would have started to tumble uncontrollably, cutting the spacecraft’s radio link with the Earth. Within a minute, the aluminium body of the craft, which is around the size of a removal van, would have melted. The last bits to go would probably have been the iridium and graphite casings that contain the probe’s 72 plutonium fuel pellets.
From the Nasa control room, these violent last moments could only be imagined; the end was indicated 83 minutes after the actual event as the signal faltered and then fell silent.
As the confirmation came in, Earl Maize, Cassini program manager, told the control room: “This has been an incredible mission, an incredible spacecraft and you’re all an incredible team. I’m going to call this end of mission.”
The news was met with subdued applause in the control room and some scientists hugged.
The dramatic end to the $4bn (£3bn) mission was partly designed to rule out the possibility of Cassini contaminating the pristine environment on Saturn’s moons Titan or Enceladus, both of which feature some of the necessary conditions for life as we know it to thrive. Cassini was also able to capture the closest images yet of Saturn’s rings during its final sequence, in which it became the first manmade object to pass between Saturn and its rings.
Prof John Zarnecki, president of the Royal Astronomical Society, who worked on Cassini for more than 20 years, said: “Of course I feel slightly sad. But it’s given me the most wonderful ride and it delivered my instrument to the surface of Titan where it’s still sitting! It has shown Titan to be even more wonderful than we had ever imagined – we’ve seen seas and lakes and rivers and dune fields and clouds and rain and more.”
Prof Martin Rees, Astronomer Royal, described the mission as one of the greatest scientific and engineering achievements in space exploration. “Cassini has given us a cornucopia of information about Saturn, its rings and its moons,” he said. “Moreover, it carried in its cargo bay a smaller robotic probe, Huygens, built by the European Space Agency, which achieved a ‘soft landing’ on Saturn’s giant moon Titan, revealing lakes and rivers of liquid methane on that exotic world. Close flybys of a smaller moon, Enceladus, confirmed that there was an ocean under the ice – perhaps the most likely location in our solar system for life.”
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