It turns out there’s way more water on Pluto than we thought

29 Jan 2016

A view from the Mission Operations Center (MOC) a few hours before New Horizons began returning images to NASA. Image via NASA/Bill Ingalls

Just when we thought that we were going to struggle to find evidence of water on Pluto, new scans of the dwarf planet have revealed that the initial small find is actually just a drop in the ocean.

The discovery that there is more water than we previously thought on the dwarf planet comes following new readings obtained from the New Horizons spacecraft, which absorbed huge quantities of data following its flyby last year using its Ralph/Linear Etalon Imaging Spectral Array (LEISA) instrument.

The two scans were taken by the LEISA instrument 15 minutes apart approximately 108,000km from Pluto and clearly show significantly greater quantities of water than initial scans suggested by combing the two new scans into a three-dimensional array at each of the LEISA-sensitive wavelengths.

However, the initial scan has created an image based off the water that was visible on a pure water ice template spectrum, which is not capable of piercing Pluto’s ice, which is particularly rich in methane, hence the more accurate image shown in the new image revealed by New Horizons.

No sign of water in Pluto’s ‘heart’

While this new model is not perfect either, it gives us an important insight into the amount of exposed water ice actually on the surface of the dwarf planet.

Despite this progress, NASA appears to be a little disappointed with the findings, which show little, if any, water ice in the giant plains of Sputnik Planum, commonly known as the giant ‘heart’ on the planet’s surface, or in the Lowell Region to the far north on the hemisphere visible to the spacecraft.

NASA has suggested that this indicates that Pluto’s vast, icy bedrock is well hidden beneath a thick blanket of other ices, such as methane, nitrogen and carbon monoxide.

Pluto scans

The old scan (left) versus the new scan (right) shows the greatly-increased level of water. Image via NASA/JHUIAPL/SwRI

Colm Gorey was a senior journalist with Silicon Republic

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