2009 · Outer edge of Saturn's B ring
Towers at the edge of Saturn's B ring (2009 equinox)
Vertical structures up to about 2.5 km tall rise from the edge of Saturn's B ring and cast long shadows, two weeks before the August 2009 equinox (Cassini, PIA11668). · NASA/JPL/Space Science Institute
WhenAugust 2009 (equinox)
WhereOuter edge of Saturn's B ring
When the Sun lit Saturn's rings edge-on at the 2009 equinox, Cassini caught shadows from vertical structures up to 2.5 to 3.5 km tall rising from the outer edge of the B ring, on rings that are normally about ten metres thick. They are attributed to kilometre-sized bodies embedded in the ring, or to particle pile-ups; neither is demonstrated.
How plausible · Very high
The towers are in Cassini's own images and peer-reviewed papers; only their cause is open.
- ●●Access Measured by NASA/JPL's Cassini.
- ●●No gain sought Published science; nobody is selling it.
- ●●Consistent over time The observation itself is not disputed.
- ●●Restraint Causes are labelled as proposed, not demonstrated.
- ●●Character record Peer-reviewed teams.
- ●●Independent convergence Spitale and Porco (2010) and a 2023 study both measure them, differing only on cause.
Plausibility weighs how well an account fits where secrecy hides the documents by design, so missing records never count against it. Strength measures what is documented. Assessed 2026-10-23.
Claims
At equinox Cassini saw vertical structures casting shadows at the B-ring edge, up to about 2.5 km high, on rings normally about 10 m thick.firsthandOn the recordNASA/JPL (PIA11668)
Structures up to about 3.5 km, attributed to kilometre-sized bodies embedded in the ring. Cause proposed, not demonstrated.analysisOn the recordSpitale and Porco (2010, Astronomical Journal)
Particle pile-ups rather than embedded bodies.analysisSourced, unconfirmed2023 DPS abstract
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