NASA picks tools for voyage to possibly LIFE-SUPPORTING moon Europa
NASA plans mission to probe warm alien globe
NASA has today announced the nine scientific instruments which will ride on a Europa-bound probe to examine the icy moon for signs of life.
NASA's Galileo mission provided strong evidence that Europa – which is about the size of Earth's moon – contains a liquid ocean beneath its frozen crust. If proven to exist, this global ocean could contain more than twice as much water than is present on Earth.
Astroboffins reckon Europa may be the best place in the solar system to look for life beyond our own planet. The moon has an abundance of salt water and a rocky sea floor, both of which are thought to be necessary for life. However, Europa does not receive the same solar warmth that Earth does as it is much further from the Sun – 483,800,000 miles away, in fact.
This would normally make the moon a cold, dead place, but the energy and chemistry provided by a process known as tidal flexing sees orbital and rotational energy dissipated as heat in the interior of the satellite. This could make Europa the best place in the solar system to look for present-day life.
“Europa has tantalized us with its enigmatic icy surface and evidence of a vast ocean, following the amazing data from 11 fly-bys of the Galileo spacecraft over a decade ago and recent Hubble observations suggesting plumes of water shooting out from the moon,” said John Grunsfeld, associate administrator for NASA's Science Mission Directorate in Washington. “We're excited about the potential of this new mission and these instruments to unravel the mysteries of Europa in our quest to find evidence of life beyond Earth.”
Wikimedia animation showing Laplace resonance of Galilean moons.
NASA's budget for 2016 includes a $30m request to formulate a mission to Europa. The mission would send a solar-powered spacecraft into a long, looping orbit around the gas giant Jupiter to perform repeated close fly-bys of Europa over a three-year period. In total, the mission would perform 45 fly-bys at altitudes ranging from 16 to 1,700 miles.
The nine selected science instruments will allow the astroboffins to study Europa, from cameras and spectrometers which will produce high-resolution images of Europa's surface and determine its composition, to an ice-penetrating radar which will determine the thickness of the moon's icy shell.
The radar will also search for sub-surface lakes similar to those beneath Antarctica. The mission also will carry a magnetometer to measure strength and direction of the moon's magnetic field, which will allow scientists to determine the depth and salinity of its ocean.
A thermal instrument will scour Europa's frozen surface in search of recent eruptions of warmer water, while additional instruments will search for evidence of water and tiny particles in the moon's thin atmosphere. NASA's Hubble Space Telescope observed water vapour above the south polar region of Europa in 2012, providing the first strong evidence of water plumes. If the plumes' existence is confirmed – and they're linked to a sub-surface ocean – it will help scientists investigate the chemical make-up of Europa's potentially habitable environment while minimising the need to drill through layers of ice.