That's what some astronomers and planetary scientists hope to see, anyhow, when the New Horizons spacecraft makes its flyby of the mysterious dwarf planet in July.
The evidence of lurking Plutonian spiders has come from some remarkable observations made over many years with ground telescopes and the Hubble Space Telescope, which can't resolve any details of Pluto's surface, but can confirm that unprecedented color and lighting changes have been underway in the last four years.
"We are pretty certain there is some kind of movement of frost," said Bonnie Buratti of NASA's Jet Propulsion Laboratory. The evidence is light curves collected by telescopes which show how the planet reflects light as it spins on its axis.
Those curves were compared to simulated light curves which assume there is no frost rising from polar ice caps and depositing in other places – darkening some places while lightening others. The modeled light curves do not match what astronomers have been seeing in recent years on the real Pluto.
"We compared it and for the last four years we've had substantial changes," Buratti told DNews.
The changes are happening at a time when Pluto is moving further from the sun, but it's also at a time when the north pole of the tilted planet is being turned towards the Sun. That creates a northern summer in the same way that summers happen on Earth. Buratti is the lead author on a paper about Pluto's discovery which has been accepted for publication by Astrophysical Journal Letters.
"We are pretty close to polar summer – so there is a lot of frost there to sublimate," she said, referring to the process where solid ice turns directly into gas, skipping the liquid phase.
The sun's rays – even at Pluto's current position 32 times further from the sun than Earth – should be enough to penetrate the nitrogen ice that's likely covering Pluto's polar cap. The ice could trap enough energy to covert some of the ice into pockets of gas. That gas would build up pressure until it blasts through the surface, spraying crystals of nitrogen ice all about in a sometimes spidery looking pattern.
This spider-making process would seem far-fetched, except that researchers have seen it before on other worlds.
Vast amounts of carbon dioxide sublimate from martian polar caps when they are warmed by the sun, not only leaving telltale patterns on the surface, but also seasonally ramping up the atmospheric pressure of the entire Red Planet.
An even better analogue, however, is Triton, Neptune's giant moon. Triton is much colder and further from the sun than Mars, and it's thought to be a veritable twin of Pluto. Like Pluto, the primary gas at work on Triton is nitrogen (on Mars it's carbon dioxide). Two gas eruptions on Triton were witnessed by the Voyager 2 spacecraft way back in 1989.
Read more at Discovery News
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