NASA’s Juno spacecraft has sent back the first-ever images of Jupiter’s north pole, which show storm systems and weather activity unlike anything previously seen on any of our solar system’s gas-giant planets.
The images were taken during the solar powered spacecraft’s first flyby of the planet with its instruments switched on.
Juno successfully executed the first of 36 orbital flybys on August 27 when the spacecraft came about 4,200 kilometres above Jupiter’s swirling clouds.
"First glimpse of Jupiter’s north pole, and it looks like nothing we have seen or imagined before," said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in the US.
"It’s bluer in colour up there than other parts of the planet, and there are a lot of storms. There is no sign of the latitudinal bands or zone and belts that we are used to – this image is hardly recognisable as Jupiter.
"We’re seeing signs that the clouds have shadows, possibly indicating that the clouds are at a higher altitude than other features," said Bolton.
One of the most notable findings of these first-ever pictures of Jupiter’s north and south poles is something that the JunoCam imager did not see, NASA said.
"Saturn has a hexagon at the north pole. There is nothing on Jupiter that anywhere near resembles that. The largest planet in our solar system is truly unique. We have 36 more flybys to study just how unique it really is," said Bolton.
The Jovian Infrared Auroral Mapper (JIRAM), supplied by the Italian Space Agency, acquired some remarkable images of Jupiter at its north and south polar regions in infrared wavelengths.
"JIRAM is getting under Jupiter’s skin, giving us our first infrared close-ups of the planet," said Alberto Adriani, JIRAM co-investigator from Istituto di Astrofisica e Planetologia Spaziali, Rome.
"These first infrared views of Jupiter’s north and south poles are revealing warm and hot spots that have never been seen before.
"And while we knew that the first-ever infrared views of Jupiter’s south pole could reveal the planet’s southern aurora, we were amazed to see it for the first time. No other instruments, both from Earth or space, have been able to see the southern aurora," said Adriani.
"Now, with JIRAM, we see that it appears to be very bright and well-structured. The high level of detail in the images will tell us more about the aurora’s morphology and dynamics," Adriani said.
Among the more unique data sets collected by Juno during its first scientific sweep by Jupiter was that acquired by the mission’s Radio/Plasma Wave Experiment (Waves), which recorded ghostly-sounding transmissions emanating from above the planet.
These radio emissions from Jupiter have been known about since the 1950s but had never been analysed from such a close vantage point.