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.
You should imagine Vivian Stanshall reading this list
Last year, NASA invited researchers to submit proposals for instruments to study Europa. Thirty-three were reviewed and, of those, nine were selected for a mission that will launch in the 2020s.
“This is a giant step in our search for oases that could support life in our own celestial backyard,” said Curt Niebur, Europa programme scientist at NASA Headquarters in Washington. “We're confident that this versatile set of science instruments will produce exciting discoveries on a much-anticipated mission.”
The nine selectees are:
- Plasma Instrument for Magnetic Sounding (PIMS) – Principal investigator Dr Joseph Westlake of Johns Hopkins Applied Physics Laboratory (APL), Laurel, Maryland – This instrument works in conjunction with a magnetometer and is key to determining Europa's ice shell thickness, ocean depth and salinity by correcting the magnetic induction signal for plasma currents around Europa.
- Interior Characterization of Europa using Magnetometry (ICEMAG) – Principal investigator Dr Carol Raymond of NASA's Jet Propulsion Laboratory (JPL), Pasadena, California – This magnetometer will measure the magnetic field near Europa and, in conjunction with the PIMS instrument, infer the location, thickness and salinity of Europa's subsurface ocean using multi-frequency electromagnetic sounding.
- Mapping Imaging Spectrometer for Europa (MISE) – Principal investigator Dr Diana Blaney of JPL – This instrument will probe the composition of Europa, identifying and mapping the distributions of organics, salts, acid hydrates, water ice phases and other materials to determine the habitability of Europa's ocean.
- Europa Imaging System (EIS) – Principal investigator Dr Elizabeth Turtle of APL – The wide and narrow angle cameras on this instrument will map most of Europa at 50 metre (164 foot) resolution, and will provide images of areas of Europa's surface at up to 100 times higher resolution.
- Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON) – Principal investigator Dr Donald Blankenship of the University of Texas, Austin – This dual-frequency ice-penetrating radar instrument is designed to characterise and sound Europa's icy crust from the near-surface to the ocean, revealing the hidden structure of Europa's ice shell and potential water within.
- Europa Thermal Emission Imaging System (E-THEMIS) – Principal investigator Dr Philip Christensen of Arizona State University, Tempe – This "heat detector" will provide high spatial resolution, multi-spectral thermal imaging of Europa to help detect active sites, such as potential vents erupting plumes of water into space.
- Mass Spectrometer for Planetary Exploration/Europa (MASPEX) – Principal investigator Dr Jack (Hunter) Waite of the Southwest Research Institute (SwRI), San Antonio – This instrument will determine the composition of the surface and subsurface ocean by measuring Europa's extremely tenuous atmosphere and any surface material ejected into space.
- Ultraviolet Spectrograph/Europa (UVS) – Principal investigator Dr Kurt Retherford of SwRI – This instrument will adopt the same technique used by the Hubble Space Telescope to detect the likely presence of water plumes erupting from Europa's surface. UVS will be able to detect small plumes and will provide valuable data about the composition and dynamics of the moon's rarefied atmosphere.
- Surface Dust Mass Analyzer (SUDA) – Principal investigator Dr Sascha Kempf of the University of Colorado, Boulder – This instrument will measure the composition of small, solid particles ejected from Europa, providing the opportunity to directly sample the surface and potential plumes on low-altitude fly-bys.
More information is available about NASA's Europa Mission here. ®