Carl Sagan’s book Pale Blue Dot was inspired by a photograph (below) taken as the Voyager 1 spacecraft left for the edge of the solar system on February 14, 1990. The portrait of our world—taken from 4 billion miles away—reveals the vastness of the cosmos relative to Earth’s pixel-sized fleck of blue.
I learned recently that hydrogen is the most common element in the universe—in fact, 75% of all atoms in our galaxy are hydrogen. Oxygen is the third most common element. So it seems no mystery that water should exist in abundance in our cosmos.
Scientists have long understood that four large planets—Jupiter, Saturn, Uranus and Neptune—contain significant quantities of water. But a recent surge of research has revealed new information about water’s presence elsewhere in our planetary system. In April, NASA revealed new details about oceans beneath the surface of both Saturn’s and Jupiter’s moons, while images from the Hubble Space Telescope provide powerful evidence that Enceladus has icy geysers and that Ganymede has a sub-surface ocean, likely sandwiched between two layers of ice.
“Water enables so many things,” Bill Larson, the NASA scientist told Space.com. “If we’re going to go out into the solar system, we’re going to have to use the resources we find at the destination.” Mined water could be used during space expeditions for drinking, growing plants, or creating fuel, he explained.
Photo by NASA (NASA) [Public domain], via Wikimedia Commons
But is extraction and in-situ utilization in space even possible? NASA engineers and scientists acknowledge that subterranean oceans would make water difficult to access. In fact, to simply locate and withdraw it would require specialized landers and equipment to drill through ice and surface materials.
One method for water extraction on Mars proposed by Edwin Ethridge, a senior In-Situ Resource Utilization scientist and retired NASA consultant, and William Kaukler of the University of Alabama in Huntsville, is to dig up the frozen soil and heat it using microwave beams until the water vaporizes.
In a lunar experiment, Ethridge and Kaukler used a conventional microwave oven to heat simulated lunar regolith, the layer of loose soil and rocks found on the moon’s surface. The heat vaporized the frozen water, which was then collected and condensed on a chilled plate. Kaukler explained that water absorbs microwaves well, while ice does not. The microwave beams heated up the rock, which melted the ice.
It makes us wonder: In the future will interstellar outposts feature Martian water?
Water’s presence elsewhere in the cosmos not only inspires optimism from a scientific and resource discovery standpoint, it has vast implications. For while the Earth is currently the only pale blue dot that we know of, where there’s water, there may be life.
