Cassini

• In fact, icy moons and dwarf planets in the outer Solar System appear to have liquid oceans below layers of thick ice.
• Recent research suggests there could even be oceans inside bodies beyond Pluto.

Tidal heating

• Io therefore overtakes Europa after every two orbits, receiving a regularly repeated tidal tug from Europa that prevents Io’s orbit from becoming circular.
• Peale’s prediction of tidal heating was vindicated only a week after publication when Voyager-1, the the first sophisticated flyby of Jupiter, sent back images of volcanoes erupting on Io.
• This isn’t likely to be due to tidal heating but instead possibly down to heat given off by decay of radioactive elements.
• Saturn has a relatively small (504km radius) icy moon called Enceladus, which has an internal ocean thanks to tidal heating from interaction with the larger moon called Dione.

Other oceans

• Puzzlingly, even for moons that should have no tidal heating, and for bodies that aren’t moons at all, evidence for internal oceans keeps mounting up.
• The authors suggest that heat from the decay of radioactive elements in the rock is sufficient to explain how these internal oceans have been kept warm enough to avoid freezing.
• It is possible that other underground oceans could be similarly inhospitable.

• David Rothery is co-leader of the European Space Agency's Mercury Surface and Composition Working Group, and a Co-Investigator on MIXS (Mercury Imaging X-ray Spectrometer) that is now on its way to Mercury on board the European Space Agency's Mercury orbiter BepiColombo.
• He is author of Planet Mercury - from Pale Pink Dot to Dynamic World, Moons: A Very Short Introduction and Planets: A Very Short Introduction.

• WASHINGTON, Oct. 12, 2023 /PRNewswire/ -- A team of scientists has produced the first complete and comprehensive global topographic map of Saturn's active icy moon Enceladus, revealing that it is even more distorted than previously thought.
• In 2009, the authors published a preliminary topographic map of less than half the surface of Enceladus that showed several of these depressions.
• The new topographic map of Enceladus is derived from almost 100 stereo image pairs of the surface acquired during the NASA Cassini mission, which were used to create topographic maps that were then integrated to produce the global topographic map product.
• These distortions in Enceladus' shape provide unique new insights into the ongoing internal dynamics of this ocean world, which will be the subject of future investigation.

• Saturn’s rings are one of the jewels of the solar system, but it seems that their time is short and their existence fleeting.
• A new study suggests the rings are between 400 million and 100 million years old – a fraction of the age of the solar system.
• This means we are just lucky to be living in an age when the giant planet has its magnificent rings.
• The rings are visible to anyone with a decent pair of binoculars or a modest back garden telescope.

Collision course

• When in-falling dust passes through, it can collide with icy particles in the rings.
• Over time, the dust gradually darkens the rings and adds to their mass.
• These may seem like lengthy time scales, but they are less than one-tenth of the 4.5 billion-year age of the solar system.

Death Star

• One in particular, the little moon Mimas, which is nicknamed the Death Star, has a 130km-wide impact crater called Herschel on its surface.
• However, Mimas is only about 400km across, so this impact would not have needed much more energy to obliterate the moon.

Ring rain

• Ultra-violet light from the Sun causes these fragments to become electrically charged via the photo-electric effect.
• Like the Earth, Saturn has a magnetic field, and once charged, these tiny icy fragments are released from the ring system and trapped by the planet’s magnetic field.
• This study demonstrated that about one Olympic-sized swimming pool of mass from the rings is lost into Saturn’s atmosphere every half-hour.

• This project, based on solutions developed by Telecom Infra Project (TIP), is the largest Open Optical and Packet Transport (OOPT) project to date.
• Multinet’s expansive upgrade incorporates Cassini, TIP’s disaggregated coherent switch and open packet transponder built by Edgecore Networks , and IP Infusion’s OcNOS, the industry’s first full-featured network OS for white box disaggregated network solutions that provides the scalable transition from traditional networks to open networks.
• “IP Infusion’s OcNOS was the clear choice to future-proof our network,” said Adnan Zaidi, Chief Operating Officer of Multinet.
• This is the largest Open Optical and Packet Transport project to date, and would not be possible without the cooperation of these market leading vendors."