The latest Pluto finding is evidence of features called "penitentes" — if confirmed this would be the first time these icy formations have been found beyond Earth. On our home planet, we know these icy spikes can grow up to several feet tall. They form in high-altitude environments, where the atmosphere is thinner and melting ice moves directly to vapor without a liquid phase in between. This sublimation (as the process is called) leaves bowl-shaped depressions behind.
But that's not all. John Moores, the lead author of the discovery paper in the journal Nature, says these features may well be in other locations across the solar system. Jupiter's Europa, for example, is a prime suspect given that radar signatures from the Galileo spacecraft suggest they could be there. But he says penitentes may even lurk in more familiar realms — even on Mars.
"We want to investigate other places in the solar system, or perhaps other solar systems, where you expect these features to show up," said Moores, who is with Canada's York University. He pointed out that penitentes may even lurk below the resolution of photos we took at planets and moons in the past. "If they were to be small, they may be in places we feel we already understand."
|This is "bladed terrain" on Pluto seen by the New Horizons Ralph/Multispectral Visual Imaging Camera. Images of the dwarf planet appear to show terrain consistent with a feature called penitentes|
What's more, the penitentes suggest that Pluto had calm atmospheric conditions over long periods of time, perhaps tens of millions of years. Regularly spaced and shaped penitentes, like what we see on Pluto, require an atmosphere; irregularly ones could develop where no substantial atmosphere is present, like Europa. Pluto's atmosphere expands and collapses as it gets further and closer from the sun in its nearly 248-year orbit. From numerical models, the team suggests that the penitentes could start growing (and continue developing) given warm enough atmospheric conditions for just a few years at a time.
Read more at Discovery News