Friday, April 27, 2007

Bionic eyes

Anyone of a respectable age remembers the six million dollar man. A man who was "rebuilt" using bionic parts that gave him super strength, hearing, and eyesight amongst other things. These days bionic parts are called neural prosthetics, they are devices that directly stimulate parts of the central nervous system or even the brain itself. The best known example is the cochlear implant that can restore hearing to the deaf by directly stimulating auditory nerves inside the ear.

There has also been some very limited success in restoring sight by implanting devices into the retina. Images from a camera are converted into electrical signals which are then used to stimulate nerve cells in the retina.

Researchers at Harvard Medical School have found another possible way to restore sight. Instead of implanting a device into the retina, they suggest implanting a device directly into the visual cortex. They have recently done this with monkeys who could "see" points of light when none were there. As the researchers sent signals into the monkey's brain the monkey would turn to look at the light that they "saw" but that wasn't in reality there.

Neuroprosthetics, though currently primitive (when compared to sci-fi standards), hold hope for many people and not just the hard of hearing or the visually impaired. For example, work is underway that has the goal of developing bionic limbs for amputees. There have already been several people who have received bionic arms which they control by thought (c.f. Luke Skywalker's arm). Other researcher are working on ways to connect brains directly to computers and even other brains, creating artificial telepathy or techlapathy as it has become known.

There is even a society of generally healthy people (transhumanists) who want implants to make themselves "better." They want x-ray vision, super strength, artificially enhanced intelligence and memory, etc. In other words they want to be rebuilt as bionic men and women. And if their brains are all connected to each, can anyone say "Borg collective?"

Here's the abstract of the research article on bionic eyes.

Wednesday, April 25, 2007

Planet discovered in star's Goldilocks zone

There has been a third planet discovered orbiting the star Gliese 581 in the constellation Libra. The planet is approximately 5 times as massive as the earth and is closer to its star than Mercury is to the Sun.

There have been over 200 exoplanets discovered so far, but most of them have been hot gas giants which are unlikely to support life, at least as we know it. However, Gliese 581 is a red dwarf type star, which means it is a lot cooler than the Sun, and this new planet is orbiting in the stars Goldilocks zone, not too hot - not too cold - but just right for water to exist in its liquid phase.

So if the planet is of the rocky-type, has water, and if its atmosphere is of the right composition, not too thick and not too thin, then it may be habitable. Those are pretty big ifs and planets like these are not thought to be rare but what is significant is that this planet is only 20.5 light years away from the Earth. This distance is large but not insurmountable.

Wednesday, April 18, 2007

Raise shields

Once outside Earth's protective magnetic field astronauts become exposed to dangerous radiation from the Sun. The Apollo astronauts were exposed to this radiation, called solar wind, on their short trips to the Moon and back. Fortunately for them, there were no major solar storms recorded during their missions. Until recently, not much had been done to tackle the problem of exposure to solar radiation. For example, current astronauts on the international space station have to retreat to a thick-walled room during times of increased solar radiation.

Looking towards the future, British scientists have announced plans to build a magnetic shield that would protect astronauts by deflecting dangerous radiation from the sun. The technology is similar to that currently used in experimental nuclear fusion reactors where a magnetic field is used to contain plasma. The proposed deflector shield would use the same magnetic field technology to keep solar radiation out. Such a shield could be deployed on spacecraft or on planets, and could be turned off when not needed.

This technology will be important to future space exploration, such as NASA's planned moon base or a NASA's planned trip to Mars. In both these missions, unprotected exposure to solar radiation could cause serious problems for the astronauts.

Deflector Shield (Star Trek Wiki)
BBC News Story