UNDER-ICE SUBMARINER: NASA's Environmentally Non-Disturbing Under-ice Robotic Antarctic Explorer (ENDURANCE) is designed to operate autonomously in frigid water. Posted on 02/16/2008 1:34:43 PM PST by BGHater
If successful at mapping lake terrain Wisconsin and Antarctica, it could be used to search for life in the ocean on Jupiter's moon
Researchers from NASA and the University of Illinois at Chicago atop the frozen surface of Wisconsin's Lake Mendota this week are preparing for interplanetary exploration. Below them, under a sheet of ice more than a foot (30 centimeters) thick, the space agency's new Environmentally Non-Disturbing Under-Ice Robotic Antarctic Explorer (ENDURANCE) maps the lake's underwater terrain. If this and subsequent voyages are successful, a similar vessel could be sent to navigate the suspected liquid water under the frozen surface of the ocean on Jupiter's moon Europa by the year 2028.
ENDURANCE, a $2.3-million project funded by NASA's Astrobiology Science and Technology for Exploring Planets (ASTEP) program, is an autonomous vehicle designed to operate underwater below the ice. Its mission: to gather environmental data (such as samples of microbial life) and create three-dimensional maps of undersea topography.
The Lake Mendota effort is a practice run for a month-long mission it is set to undertake later this year in Antarctica's permanently frozen Lake Bonney, which is coated with up to 15 feet (4.5 meters) of ice. The lake, which is about 2.5 miles (four kilometers) long, one mile (1.6 kilometers) wide, 130 feet (40 meters) deep and located in the continent's McMurdo Dry Valleys, was chosen because its extreme conditions are about as close as it gets on Earth to those ENDURANCE might encounter on Europa. If this trip to Antarctica is successful, ENDURANCE will do a second mapping next year.
All data gathered from these expeditions will be sent to the University of Illinois's Electronic Visualization Laboratory, where researchers will create 3-D images, maps and data renderings of the lake. ENDURANCE begins mapping from the melt hole through which it enters the water. Using the GPS coordinates of the opening, the vehicle's positions are determined data gleaned from sensors that measure temperature, light and the water's chemistry. During its eight-hour missions, gathered information is stored on board using flash disk memory for later recovery and analysis on the surface.
Workers cut a 10-foot (3.1-meter) by 14-foot (4.3-meter) rectangular dive hole with a chainsaw to prepare an entry point for ENDURANCE in Lake Mendota's icy surface. Because ENDURANCE enters and leaves its underwater habitats via ice holes, it is designed to be a compact vehicle—about 4.7 feet (1.4 meters) long, 3.5 feet (1.1 meters) wide, and 2.6 feet (0.8 meter) high and weighing about 176 pounds (80 kilograms) on land. The propulsion chassis uses commercial components along with custom-designed flight electronics and thrust vector controllers. Maximum vehicle speed is anticipated to be as much as five feet (1.5 meters) per second.
Most of the onboard scientific instrumentation is fiber-optic-based and mounted along the wall of a flow-through tube that runs the entire interior length of the vehicle. Chloride and conductivity probes sense the same flow stream at the rear of the vehicle. A digital camera with lighting sits on the starboard bow (located on the right, if you are facing the sub's front) for capturing visible spectrum images within each volume pixel (voxel) as well as for taking bottom sediment images. Three-dimensional images are composed of voxels in the same way that two-dimensional ones are built from pixels.
ENDURANCE, which runs on two lithium ion batteries, detects and avoids obstacles using sonar arrays mounted on the bow, port (left) and starboard sides that can alert the vessel about an object up to 328 feet (100 meters) away. The sonar's detection range is expected to give ENDURANCE at least a minute before it reaches any obstacle.
An ultrashort baseline transceiver is lowered into the water once ENDURANCE submerges and emits signals that give the autonomous vessel a point of reference. This aids the vessel's mapping mission and also helps the researchers retrieve their robot sub. A malfunction that might cause ENDURANCE to get lost or be unable to make its way back to the entry hole would be disastrous due to the harsh conditions in which it operates. "When you put something in a lake in Antarctica, you don't want to lose it," says John Rummel, a NASA senior scientist for astrobiology.
ENDURANCE is a follow-up to the Deep Phreatic Thermal explorer (DEPTHX) , a NASA-funded project led by StoneAerospace, Inc., a Del Valle, Tex.based maker of technology used to explore the ocean depths as well as deep space. DEPTHX last year underwent extensive underwater field tests in Mexico, and its success has paved the way for ENDURANCE's missions.
Whereas the DEPTHX was tested in waters that were a balmy 86 degrees Fahrenheit (30 degrees Celsius), ENDURANCE will encounter 32-degree F (0-degree C) conditions in Lake Bonney, whose stratified waters contain both fresh- and salt- water. Nearest its surface, Bonney has a layer of about 16 feet (five meters) of freshwater atop about 110 feet (33.5 meters) of saltwater, the latter of which is three times as saline as normal seawater, Rummel says. This increased saltiness will cause ENDURANCE's sonar waves to behave differently, bouncing upward more than they would in fresh or less briny water.
NASA's otherworldly aspirations for ENDURANCE include a trip to Europa, which Rummel says the agency hopes to pull off within in two decades. ENDURANCE has to prove its mettle on Earth, however, before it is ready to dive under Europa's ocean, which features up to 12 miles (20 kilometers) of ice atop water that could be around 62 miles (100 kilometers) deep. Once there, ENDURANCE could play a very special role in space exploration, Rummel says, adding, "It could very well be the first vehicle to find extraterrestrial life."
UNDER-ICE SUBMARINER: NASA's Environmentally Non-Disturbing Under-ice Robotic Antarctic Explorer (ENDURANCE) is designed to operate autonomously in frigid water.
ENDURANCE'S top shell resembles a crab, but its underbelly has a variety of sensors that measure temperature, light and water chemistry during its eight-hour missions.
FROZEN FRONTIER: ENDURANCE entered Wisconsin's Lake Mendota via a 10-foot (3.1 m) by 14-foot (4.3 m) rectangular dive hole cut using chainsaws.
ICY RECEPTION: Rather than diving right in (literally) ENDURANCE was initially suspended just below Lake Mendota's surface to see how its controls and its two lithium ion batteries would function in the cold.
DIVING IN: Prior to ENDURANCE's descent, a triangular hole was cut so a diver could check to see there were no ice formations that might damage the robotic sub.
All these worlds are yours, except Europa. Attempt no landing there.
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ALL THESE WORLDS ARE YOURS EXCEPT EUROPA ATTEMPT NO LANDING THERE |
Yeah, but Roy Scheider died last week so it’s ok.
Very cool
Great minds think alike :-)
Great. He'll be going to Europa too, I'm guessing.
I guess we’ll find out if the crust on Europa is “thick” or “thin” and answer that debate, but I didn’t see any notation as to the method for breaking through the granite-like icy crust. Endurance has to reach the liquid below the surface before it will be of use. Has anyone kept up with NASA’s design for the equipment to accompany Endurance?
I would think the equipment to melt through Europa’s ice would be more complex, heavier and consume far more power than the probe itself.
Making a probe/submarine is child’s play compared to the rest.
Testing this in Wisconsin, they just HAD to make it look like it’s covered in cheese.
I see how it is....
Requiring an ice hole is a mistake. The probe should be equipped with a shell that will change the ionic structure of the ice to melt it.
Much like how salt melts ice, a coating of some material that melts the *type* of ice, not necessarily water ice, that the probe will land on.
For example, if it was ordinary water ice on Earth, and you had a shell around a ball which contained a half foot thick crust of crystallized hard salt, with gaps in the shell so that the ice would touch the salt. That much salt could melt through a LOT of ice, by changing its ionic structure, *not* by warming it.
Can’t imagine them pulling this off. The pressure’s got to be horrendous, even though gravity’s only one seventh or one eighth that of earth. I mean, the pressure under 12 miles of ice would be like being under 1.6 miles of ice on earth. Then the idea that you could go very deep into this 60 mile deep ocean on top of that... It just ain’t gonna happen; i.e., we definitely won’t be looking at any hydrothermal vents, imo.
But I’m rooting for them though! It’s absolute genius. Best case: It survives and roams the upper layers of Europa’s ocean(s) for years, suffering no breakdowns, reporting back periodically to earth, sending pics of it frolicking with mile-long ice whales, etc.
It’s going to have a hot nuclear mass of fuel ... (plutonium?) that allows it to melt through the ice and at the same time provide the sub with power.
</sarc> or link please? It runs on lithium batteries, I didn’t see any mention of your suggestion.
The model runs on lithium batteries. They are not going to put plutonium in a pristine Arctic or Antarctic lake. I’ll try to find a link but no guarantees; I saw it on the Science Channel.
Haven't seen this particular cryobot mentioned before and think it's probably just one of many designs they're looking at. Gonna keep looking...
LOL, absolutely series! It’s fascinating stuff, huh? I’m very excited about it.
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