Saturday, May 13, 2017

Phys.org Heralds a Planetary Stethoscope for Europa - Science

The headline is overstated since this is not about a stethoscope but it shows interesting technology for further discovery about distant planets.

Europa has been a fascination for years because we know something is living there but we haven't found it yet.  Europa and Enceladus were announced as the NASA favorites for further exploration and the Rockhouse loves that move.

However, there is not currently any planetary stethoscope.

Phys.org:   'Planetary stethoscope' could determine what lies in Europa's global ocean

NASA:  what do you mean we know?  We don't know!

Oh, yes; we know.  We just need to go there to find it, don't we.



Europa's surface is a shell of ice covering a global ocean and displaying amazing features. Long, linear cracks and ridges crisscross the surface, broken by regions of disrupted terrain where the surface ice crust has cracked and refrozen into new patterns. The colors seen in this image from the Galileo mission in the late 1990s are approximately what the human eye would see. 

Credit: NASA/JPL-Caltech

- PO

When there's that much water, the chances of something living in it are high and NASA is determined to find out what's there.


Scientists have speculated for decades what lies within that ocean. It is larger in volume than all the oceans of Earth put together.

A NASA-funded seismometer under development at Arizona State University holds the promise of landing on Europa's ice shell—and listening to it.

The seismometer would use Europa's natural tides and other movements to discover the shell's thickness, see whether it holds pockets of water—subsurface lakes—within the ice, and determine how easily, and how often, ocean water could rise and spill out on the surface.

"We want to hear what Europa has to tell us," said Hongyu Yu, of ASU's School of Earth and Space Exploration. "And that means putting a sensitive 'ear' on Europa's surface."

- PO

The technology is cool and, technically, it does penetrate the surface but we want a stethoscope which can go down there and look.  We need water samples to detect the presence of amino acids; we want the big bang ... is there life or isn't there.


It seems we must take the baby steps and Arizona does want the same thing.

Europa can be glimpsed in binoculars from the backyard as it circles Jupiter once every 85 hours. But it's just a point of light, looking no different from what Galileo saw when he discovered it.

The Europa that scientists study today, however, is more properly considered an ocean world. This is because of two flyby spacecraft (NASA's Voyager 1 and 2) and an orbiter (NASA's Galileo) that spent eight years at Jupiter. Long-distance observations of Europa also have come from the Hubble Space Telescope orbiting Earth, which detected plumes of water vapor erupting from the shell in 2012 and 2016.

"At Europa, we're trying to use seismometers to determine where the liquid water lies within the ice shell," team member Rhoden said. "We want to know how active the ice shell is."

The answers to these questions are important to the future exploration of this moon and its habitability, she said. "An active shell with pockets of water creates more niches for life and more ways to transport nutrients from the ocean to the surface."

Locating these pockets on Europa would allow future lander missions to possibly sample ocean water brought up through the ice shell.

- PO

There's much more in the original article for the interested junior astronaut.

No comments: