Iapetus, Charon Look Young for Their Age
Hard bodies in the solar system are supposed to be billions of years old. Why, then, do so many look smooth and young-looking? Two examples made news today:
- Charon So Smooth: Pluto has a moon named Charon (KAR-on) that apparently leaks beauty cream out of its interior. Live Science and Space.com report about a study of Charon’s spectrum in the July 10 Astrophysical Journal that indicates it is being resurfaced by cryovolcanism. They detected crystalline ice that would normally become amorphous in tens of thousands of years. Though the paper claims water leakage is recoating the surface at a snail’s pace, it is remarkable that a body this small, this far from the sun, in the cold outer regions of the solar system, would be active at all.
A press release from Gemini Observatory describes how astronomers detected the ice coating using spectra obtained through adaptive optics. It says, “This action could be occurring on timescales as short as a few hours or days, and at levels that would recoat Charon to a depth of one millimeter every 100,000 years.” These estimates, of course, were inferred from spectra without actually being able to see the eruptions. Cryovolcanism, where water erupts outward through cracks in the surface (as on Enceladus), was proposed as the only mechanism to explain the presence of crystalline ice. For this to occur, a large portion of the interior must consist of liquid water, and it must be able to propagate through cracks. As water approaches the freezing point and expands, the article says it could propagate up half a kilometer to the surface in a matter of hours.
But how could this small moon retain water? The astronomers detected the signature of ammonia hydrates, which depress the freezing point of water and presumably allow the interior to remain liquid. Ammonia hydrates have also been detected on Quaoar and at least one other KBO (Kuiper Belt Object). Signs of active cryovolcanism have also been seen on Ariel, a moon of Uranus. Ariel may have been subject to tidal flexing in the past, the article says. “By contrast, Kuiper Belt Objects (KBOs) such as Charon, Quaoar, Orcus, and others are not tidally squeezed,” the press release states. “Yet, they seem to show evidence of cryovolcanism.” The only other source of heat they suggested was internal radioactivity. Other KBOs larger than 500 km across also show crystalline ice on their surfaces, suggesting that cryovolcanism may be a common feature of these icy bodies in the outer solar system.
An artist’s conception of Charon accompanying the press release shows eruptive plumes spraying crystalline snow onto the surface. Close-up observations of Charon may be obtained when the New Horizons spacecraft flies by in 2015.
- Iapetus Youthful Figure: That’s JPL’s headline: “Saturn’s Old Moon Iapetus Retains its Youthful Figure.” A press release claims that “The moon has retained the youthful figure and bulging waistline it sported more than three billion years ago,” leaving the question unanswered why it stands alone in that respect. “Unlike any other moon in the solar system, Iapetus is the same shape today as it was when it was just a few hundred million years old; a well-preserved relic from the time when the solar system was young.”
The model published in Icarus requires large amounts of short-lived radionuclides to heat the interior, and a rapid spin that created the equatorial bulge. But then what happened? “The challenge in developing a model of how Iapetus came to be ‘frozen in time’ has been in deducing how it ever became warm enough to form a bulge in the first place, and figuring out what caused the heat source to turn off, leaving Iapetus to freeze.” Despite these challenges, the scientists feel it tells them Iapetus must be “roughly 4.564 billion years old.”
National Geographic claimed the mystery of Iapetus’ shape is “solved,” but this represents just one competing model and does not answer all the questions, such as the origin of its equatorial mountain range, the source of the dark material that coats half the moon, and the reasons this particular moon would have had such different initial conditions from its neighbors. Extreme close-up images of Iapetus are hoped for when Cassini flies by on September 10 at less than 1,000 miles above the surface.
These announcements should be considered in the context of other recent announcements about age anomalies, such as Enceladus and its geysers (05/21/2007 and 04/20/2007), Titan’s low crater count (03/28/2007), lunar transients on our moon (07/12/2007, activity on Saturn’s Tethys and Dione (06/16/2007), Mercury’s magnetic field (05/04/2007) and indications of activity in Kuiper Belt objects (03/31/2007).
You never see these planetary scientists proving the solar system is billions of years old. You only see them assuming it. Then, because that parameter cannot be altered, you see them squirm and wriggle the models to fit young-looking phenomena into old ages. Proposing an ad hoc set of conditions that might fit the data is not the same as proving this is what happened, so National Geographic was way out of line to claim the mystery of Iapetus has been “solved.”
As to the “roughly 4.652 billion years” figure, that is ridiculous. What did they expect, the exact month and year? There’s no way the evidence from Iapetus can yield a date to four significant figures without assuming the very thing they ought to be proving. Dates are inextricably linked to the assumptions made. Those assumptions should have been stated up front. They have blindly accepted a consensus date from uniformitarian, evolutionary theories, and molded their data to fit it. Yet they spoke of these dates as facts.
Good thing the planets don’t talk back, because that wouldn’t go over too well on a date. Imagine a college student telling his sweetheart, “Your figure is so youthful, and your skin so smooth; you look mighty young for a 4500-year-old.”