Giant telescope opens both eyes

The world's most powerful optical telescope has opened both of its eyes.

Astronomers at the Large Binocular Telescope (LBT) in Arizona have released the first images taken using its two giant 8m diameter mirrors.

The detailed pictures show a spiral galaxy located 102 million light-years away from the Milky Way.

LBT has been 20 years in the making but promises to allow astronomers to probe the Universe further back in time and in more detail than ever before.

"The amount of time and work that was put into this project to reach the point where we are today is immense,"

said LBT Director Richard Green.

"To see the telescope operational with both mirrors is a great feeling."

The $120m (£60m) telescope uses two mirrors in tandem to maximise the amount of light it gathers, which allows astronomers to look deep into the Universe.

Using two 8.4 m (27ft) mirrors will give LBT the equivalent light-gathering capacity of a single 11.8m (39ft) instrument and the resolution of a 22.8m (75ft) telescope.

Impressive detail

The resolution is 10 times greater than the space-based Hubble telescope, which has a 2.4m (8ft) mirror.

"The images that this telescope will produce will be like none seen before,"

said Professor Peter Strittmatter of the University of Arizona.

The first pictures are false-colour images of the spiral galaxy NGC 2770. The pictures show what is a flat disc of stars and glowing gas.

The images - which take advantage of the telescope's ability to view the same point in space with multiple wavelengths of light - emphasise different features of the galaxy.

Combining ultraviolet and green light shows up clumpy regions of newly formed hot stars in the spiral arms, whilst a combination of red wavelengths highlights older, cooler stars.

The images were taken on 11 and 12 January but have only just now been released.

The LBT is located on Mount Graham in southeastern Arizona. It achieved "first light" with one mirror on 12 October 2005 when it imaged a spiral galaxy in the constellation of Andromeda.

Sea slug inspires brain implant

The response of a startled sea cucumber has inspired a new material that could one day be used to build brain implants for patients with Parkinson's disease.

The material can rapidly switch from being rigid to flexible and vice versa.

Writing in the journal Science, US researchers describe how species of the sea creatures "tense" when threatened.

The new material mimics this ability, and could be used to make advanced brain electrodes which are stiff when implanted, yet supple inside the body.

Adding water changes the state of the material.

"The water acts as a chemical switch,"

Dr Christoph Weder, one of the team who developed the material, told the BBC News website.

This is important as the brain is around 75% water.

Chemical change

The material consists of naturally occurring nanofibres, or "whiskers", carefully embedded in a polymer.

The cellulose fibres, each just 25 nanometres (billionths of a metre) in diameter, are taken from a different sessile sea creature known as a tunicate or sea squirt.

"There are many sources of nanofibres such as cotton or wood,"

said Dr Weder.

The structure of the un-named material mimics the skin of sea cucumbers which have collagen nanofibres embedded in a soft connective tissue.

"These creatures can reversibly and quickly change the stiffness of their skin,"

explained Dr Jeffrey Capadona, another member of the team.

"Normally it is very soft; but for example in response to a threat, the animal can activate its 'body armour' by hardening its dermis."

Changes to the stiffness of the sea cucumber's skin are thought to be triggered by chemicals secreted by the animal's nervous system that rearrange the collagen threads.

"Our architecture is the same, but the chemistry is different,"

explained Dr Weder.

In the absence of water, the nanofibres are held together by chemical links known as hydrogen bonds. This gives the material its rigidity.

When exposed to water, the water molecules "competitively bond" with the fibres.

"The water also likes to stick to the cellulose,"

said Dr Weder.

This has an effect of "ungluing" the fibre-to-fibre bonds, and the material becomes about 1,000 times softer, with the consistency of rubber.

When the water evaporates, a network of cross-linked whiskers reforms, stiffening the material.

Brain aid

This ability to morph could help build therapeutic devices to be implanted into the brains of patients who suffer from Parkinson's disease, stroke or spinal cord injuries.

At present, there are a number of research teams hoping to develop "artificial nervous systems" that aim to treat these disorders.

These systems need to "plug" into nerve cells within the brain - known as cortical neurons - to record electrical activity.

But animal studies have shown that the quality of the brain signals recorded by implanted electrodes often degrades after a few months.

One hypothesis is that stiff electrodes damage the surrounding brain tissue.

"There is a mechanical mismatch - the electrode is rigid but the brain is more like jello,"

said Dr Weder.

The team believes that an implant built on a substrate of the new material could overcome this problem, by being rigid during implantation, and softening once in the body.

Dr Weder also has his eye on other applications for the material. Potentially, electricity rather than water could be used to switch its state.

"Smart bullet proof vests, prosthetics - the list goes on and on,"

he said.

Pentagon bans Google map-makers

The US defence department has banned the giant internet search engine Google from filming inside and making detailed studies of US military bases.

Close-up, ground-level imagery of US military sites posed a "potential threat" to security, it said.

The move follows the discovery of images of the Fort Sam Houston army base in Texas on Google Maps.

A Google spokesman said that where the US military had expressed concerns, images had been removed.

Google has now been barred from filming and conducting detailed studies of bases, following the discovery of detailed, three-dimensional panoramas online - and in particular, views of the Texan base.

"Images include 360-degree views of the covered area to include access control points, barriers, headquarters, facilities and community areas,"

said the defence department in a statement quoted by AFP news agency.

It said such detailed mapping could pose a threat.

Google spokesman Larry Yu said the decision by a Google team to enter the Texas base and undertake a detailed survey, had been "a mistake".

He told the BBC that it was "not our policy to request access to military installations, but in this instance the operator of the vehicle with the camera on top - which is how we go about capturing imagery for Street-View - requested permission to access a military installation, was given access, and after learning of the incident we quickly removed the imagery".

Individuals and governments

Military officials are currently looking into exactly what imagery is available - though it may not be able to order its removal if images are taken from public streets.

Among the popular mapping services offered by Google are Street View, which allows web users to "drive" along virtual US landscapes with ground-level views, and Google Earth, which offers detailed satellite and 3D images of locations around the world.

In this case, it was imagery offered on Street View that caused the concern.

But both have provoked complaints - from individuals depicted in the images and from governments concerned that satellite images could compromise security.

Gary Ross, a spokesman for the US Northern Command, told AFP that although such services could be useful, "there has to be a balance".

But Mr Yu said Google would listen to concerns about privacy and security.

"We try to have a compliant image removal policy - not only relative to the military but to consumers also,"

said Mr Yu.

"If people have concerns, they should contact us."