Hidden depths
Slight modifications within the orbit of Saturn’s moon Mimas trace on the presence of an unlimited, younger ocean beneath the satellite tv for pc’s icy floor that will have shaped between 5 million and 50 million years in the past, Adam Mann reported in “This Saturn moon might harbor water” (SN: 3/9/24, p. 8).
Reader Bobby Baum requested how the ocean shaped so lately and whether or not an ocean might have shaped a number of occasions up to now.
Saturn’s moons gravitationally work together with each other and with their ringed mum or dad planet as they orbit. This complicated dance causes tidal stresses on the moons, producing warmth that may soften a satellite tv for pc’s icy inside.
The putative ocean beneath Mimas’ floor most likely shaped due to such an interplay with a minimum of one of many different Saturnian moons within the current previous, says Valéry Lainey, an astronomer on the Paris Observatory. “We have no idea but which [other] moon is chargeable for this, however such interactions are quite common in celestial mechanics,” Lainey says.
The subsurface ocean most likely didn’t exist earlier in Mimas’ historical past, Lainey and colleagues suspect. That’s as a result of the crew has not seen any proof of floor deformations {that a} thick, liquid ocean would have brought on.
Youngsters’ creations?
Radiocarbon relationship means that historical cave work in Argentina are practically 8,200 years outdated. That age implies that the area’s rock artwork custom, which most likely preserved cultural information shared by hunter-gatherers, is a number of millennia older than earlier proof suggests, Bruce Bower reported in “Patagonian cave saved tradition alive” (SN: 3/9/24, p. 16).
Reader Joan questioned if kids, reasonably than adults, might have created the traditional artwork. “I typically had my kids draw and paint after they couldn’t play outdoors. If I used to be caught in a cave with my kids, they’d have been portray on the partitions,” Joan wrote.
“There isn’t a method to know for positive who made these cave work,” Bower says. Some researchers have lengthy suspected that Stone Age kids and youngsters used their fingers to impress line patterns on cave partitions, in addition to go away behind kid- and teen-sized hand stencils inside caves (SN: 4/28/07, p. 264). “If younger folks made some or the entire cave work in Argentina, they participated in what might have been a system for transmitting cultural information that lasted over 3,000 years,” Bower says.
