Water in the Solar System:
Water, Water, Everywhere!
Water, Water, Everywhere!
Ice geysers erupt on Enceladus, a bright and shiny inner moon of Saturn.
(Image Credit: NASA/JPL/Space Science Institute)
Planetary scientists once thought Earth was an oasis in a dry solar system, as early missions to our neighbors revealed desert-like conditions on the Moon, Mars, and Mercury. In contrast, our Earth is literally covered with water.
Missions in recent years have overturned our view of a dry solar system, returning mounting evidence of ample water from a vast array of locations.
The Moon, once thought dry-as-a-bone, has a water cycle -- with small amounts of water moving across its surface -- and millions of tons of water ice locked into frozen crater floors at its poles. Rings of ice orbit the gas giants, and several moons of these distant worlds have immense oceans of liquid water beneath their frozen crusts.
Even Mercury has ice in the dark craters at its poles, as investigated by the ongoing MESSENGER mission.
Water is critical to life and to future human forays into space. While we now know that Earth is not the only place with water, it is the only oasis that contains life [as far as we are aware - MS]. We should remember to take care of our water resources on our home planet, even as we are discovering water almost everywhere in our solar system!
Scientists Say Life Is Likely On Enceladus, Saturn’s Icy Moon
Scientists have turned their attention to yet another celestial body in our solar system – Enceladus – as a potential site for life outside of the Earth.
Scientists announced in a new study published in Nature that the icy moon of Saturn likely has an active hydrothermal system. That means that there is warm running water under the icy, cracked, cratered surface of this moon.
Enceladus first indicated itself a candidate for life outside of our planet when Cassini saw plumes of water vapor bursting from its south pole in 2005. It was unclear up until now where those plumes were coming from and why.
A team of researchers led by the University of Colorado’s Laboratory for Atmospheric Space Physics found small grains of rock with the Cassini spacecraft that they believed were formed by the hydrothermal vents in the hidden ocean of Enceladus. The grains are rich in silicon, much like sand and quartz here on Earth, which are commonly formed in a hydrothermal process.
The paper’s authors spent four years studying the data from the Cassini spacecraft and performing computer simulations. Their conclusion?
“We methodically searched for alternative explanations for the nanosilica grains, but every new result pointed to a single, most likely origin.” says Frank Postberg in the ESA’s release on the study. Postberg is a scientist who works with Cassini’s dust analyzer data at the University of Heidelberg in Germany and is a co-author on the paper.
This news is exciting because it means Enceladus could realistically harbor life under the icy tomb of its surface. Warm water is one of the basic ingredients for life as we know it. These are exciting times.
NASA Confirms The Presence Of An Ocean On Ganymede, Jupiter's Largest Moon : Life Might Exist
NASA has announced the presence of an ocean under the surface of Ganymede, Jupiter’s largest moon and the largest moon in the solar system. Aurorae spotted by the Hubble Space Telescope confirmed the theory and the finding was announced in a teleconference.
Scientists have speculated since the 1970s that Ganymede could have an ocean under its surface, but until now there was little evidence to support the theory.
Hubble was able to collect seven hours worth of data studying the aurorae in the moon’s thin atmosphere. An aurora itself doesn’t prove that an ocean exists, but when an ocean is present, the behavior of aurorae change. If there wasn’t an ocean on Ganymede, the aurorae would rock back and forth across six degrees of the moon’s circumference as it orbited Jupiter, the nearby gas giant.
But a salty, electrically conductive ocean locks the aurorae in a much more stable position. Ganymede’s aurorae could only move about two degrees. While Hubble pictured the aurorae as blue, they would appear red from the moon’s surface.
Ganymede, the solar system’s largest moon – nearly as big as mars – is a fascinating one. It’s the only moon in the solar system with its own magnetic field generated by a molten iron core, similar to Earth’s. The thin atmosphere is also rich in oxygen. But the discovery of an ocean on Ganymede doesn’t necessarily make the moon a good place to look for life. The ocean is likely 100 miles below the surface, making it nearly impossible to study. Even if we were to drill to the ocean, scientists think the ocean is likely locked in ice, making it improbable life would evolve there. It likely lacks the hydrothermal system found on Enceladus.
The European Space Agency is planning a mission back to the Jupiter system in the 2020s that will look more closely at moons like Callisto, Ganymede and Europa – all three being candidates for water.
“As far as we can tell, almost everywhere we look there’s water,” Heidi Hammel said during the conference, who is the executive vice president of the Association of Universities for Research in Astronomy. “Water, water, everywhere in our solar system.”
Thanks to NASA and Higher Perspective for the above information.