Some blind people develop the ability to echolocate. A paper in Royal Society Open Science probes further (outside their paywall)
Normally sighted people were blindfolded and taught how to produced high-frequency clicks with their tongues. They were led into a narrow, long hall and practiced echolocation. Within a few weeks most of them became good at it. Then a virtual version of the corridor was created. It was noted that being able to move the torso and head was critically important to successful navigation.
Perhaps a variation of the apparatus could be used to teach the blind how to hone their echolocation skills.
Self-motion facilitates echo-acoustic orientation in humans
Ludwig Wallmeier1,2 and Lutz Wiegrebe1,2
1 Division of Neurobiology, Department Biologie II, and 2 Graduate School of Systemic Neurosciences, Ludwig-Maximilians-Universität München, Großhadernerstr. 2, 82152 Planegg-Martinsried, Germany
The ability of blind humans to navigate complex environments through echolocation has received rapidly increasing scientific interest. However, technical limitations have precluded a formal quantification of the interplay between echolocation and self-motion. Here, we use a novel virtual echo-acoustic space technique to formally quantify the influence of self-motion on echo-acoustic orientation. We show that both the vestibular and proprioceptive components of self-motion contribute significantly to successful echo-acoustic orientation in humans: specifically, our results show that vestibular input induced by whole-body self-motion resolves orientation-dependent biases in echo-acoustic cues. Fast head motions, relative to the body, provide additional proprioceptive cues which allow subjects to effectively assess echo-acoustic space referenced against the body orientation. These psychophysical findings clearly demonstrate that human echolocation is well suited to drive precise locomotor adjustments. Our data shed new light on the sensory–motor interactions, and on possible optimization strategies underlying echolocation in humans.
Unmanned space exploration tends to be much more interesting than the manned variety - after all, it can go to more interesting places and is much less expensive.
An attempt to land on a comet is amazing. Rosetta is currently orbiting comet 67P and its module Philae is about a day away from an attemted landing. Here's a timeline for the landing and a bit on Philae's instrument package.
A few interesting factoids --
° the comet is currently shedding about 5 liters of water a second - that will increase dramatically as it approaches the Sun
° the landing team needs to know the relative velocity of the comet and Philae to better than one cm/s
° 67/P is a small object - two lobes (it looks roughly like a bathtub duck) and a total mass of about 1013 kg.
° the gravitational force on the comet's surface is about a millionth that of Earth. Escape velocity is about a meter per second - a very slow walking speed. You could easily jump into space from its surface.
° a lot of intersting science is being done. My candidate for the most intersting is CONSERT - radio tomograpy on a comet nucleus