Optics

A record two-hour observation of Jupiter using a new technique to remove atmospheric blur has produced the sharpest whole-planet picture ever taken from the ground. The series of 265 snapshots reveal changes in Jupiter's smog-like haze, probably in response to a planet-wide upheaval more than a year ago.

Being able to correct wide field images for atmospheric distortions has been a goal for decades. The new images of Jupiter prove the value of the advanced technology used by the Multi-Conjugate Adaptive Optics Demonstrator (MAD) prototype instrument mounted on ESO's Very Large Telescope (VLT), which uses two or more guide stars instead of one as references to remove the blur caused by atmospheric turbulence over a field of view thirty times larger than existing techniques.

Telescopes on the ground suffer from a blurring effect introduced by atmospheric turbulence. This turbulence causes the stars to twinkle in a way that delights the poets but frustrates the astronomers, since it smears out the fine details of the images. However, with Adaptive Optics (AO) techniques, this major drawback can be overcome so that the telescope produces images that are as sharp as theoretically possible, i.e., approaching conditions in space.


Prof. Leonid Yaroslavsky from Tel Aviv University believes that humans may have an ability to "see" colors and shapes - with their skin.

He outlines his 'optic-less imaging model' in a chapter of a new book, "Advances in Information Optics and Photonics", and even says it could lead to a new form of optical imaging technology that beats the limitations of today's lens-based imaging devices. This model, he says, may also explain how a controversial primordial instinct might have evolved over millions of years.

Astronomical instruments needed to answer crucial questions, such as the search for Earth-like planets or the way the Universe expands, have come a step closer with the first demonstration at the telescope of a new calibration system for precise spectrographs. The method uses a Nobel Prize-winning technology called a 'laser frequency comb', and is published in this week's issue of Science.

"It looks as if we are on the way to fulfil one of astronomers' dreams," says team member Theodor Hänsch, director at the Max Planck Institute for Quantum Optics (MPQ) in Germany. Hänsch, together with John Hall, was awarded the 2005 Nobel Prize in Physics for work including the frequency comb technique.


Scientists at Tufts University's School of Engineering have demonstrated for the first time that it is possible to design an edible optical sensor that can be placed in produce bags to detect harmful levels of bacteria and consumed right along with the veggies. This same technology could mean an implantable device that would monitor glucose in your blood for a year, then dissolve.

Such "living" optical elements that could enable an entirely new class of sensors. These sensors would combine sophisticated nanoscale optics with biological readout functions, be biocompatible and biodegradable, and be manufactured and stored at room temperatures without use of toxic chemicals. The Tufts team used fibers from silkworms to develop the platform devices.

We have long been fascinated by the concept of absolute zero, the temperature at which everything comes to a complete stop, but physics tells us absolute zero cannot be reached but only approached - and the closer you get, the more interesting phenomena you find.

Three scientists from ESF's EUROCORES Programme EuroQUAM gave insight into this 'cool' matter at the event "The Amazing Quantum World of Ultra Cold Matter", held at this year's ESOF (Euroscience Open Forum) in Barcelona. It was co-organized by the European Science Foundation (ESF) and The Institute of Photonic Sciences (ICFO) within the collaborative research programme "Cold Quantum Matter" (EuroQUAM).

Maciej Lewenstein leads the quantum optics theory group at ICFO and is a Humboldt Research Prize Awardee.

Engineers working in optical communications bear more than a passing resemblance to dreamers chasing rainbows.

They may not wish literally to capture all the colors of the spectrum, but they do seek to control the rate at which light from across the spectrum moves through optical circuits.

This pursuit is daunting when those circuits contain dimensions measured in nanometers.

At the nanoscale, says Qiaoqiang Gan, a Ph.D. candidate in electrical engineering at Lehigh University in Bethlehem, Pa., engineers hoping to integrate optical structures with electronic chips face a dilemma.

An international team has reached a milestone in the construction of one of the largest ever cameras to detect the mysterious Dark Energy component of the Universe. The pieces of glass for the five unique lenses of the camera have been shipped from the US to France to be shaped and polished into their final form. The largest of the five lenses is one metre in diameter, making it one of the largest in the world.

Each milestone in the completion of this sophisticated camera brings us closer to detecting the mysterious and invisible matter that cosmologists estimate makes up around three quarters of our Universe and is driving its accelerating expansion. Observations suggest that roughly 4% of the Universe is made up from ordinary matter and 22% from Dark Matter; this leaves 74% unaccounted for - the so-called Dark Energy.

The Dark Energy Survey (DES) camera will map 300 million galaxies using the Blanco 4-meter telescope - a large telescope with new advanced optics at Chile’s Cerro Tololo Inter-American Observatory.


Researchers at the Fraunhofer Institute have taken a page from sports physiology and developed a low-cost optical sensor to measure the force with which tiny, migrating somatic cells push themselves away from an underlying surface. Force analysis devices like these could help to identify specific cell types more reliably than using a microscope or other conventional methods.

The sensor consists of a smooth surface that is studded with 250,000 tiny plastic columns measuring only five microns in diameter, rather like a fakir’s bed of nails. These columns are made of elastic polyurethane plastic. When a cell glides across them, it bends them very slightly sideways. This deflection is registered by a digital camera and analyzed by a special software program.

The researchers working with project manager Dr. Norbert Danz of the Fraunhofer Institute for Applied Optics and Precision Engineering IOF in Jena have already shown that their ‘Cellforce’ sensor works. It will be the task of initial biological tests to show how different cell types behave.


Astronomers have discovered an extrasolar planet only three times more massive than our own, the smallest yet observed orbiting a normal star. The star itself is not large, perhaps as little as one twentieth the mass of our Sun, suggesting to the research team that relatively common low-mass stars may present good candidates for hosting Earth-like planets.

The astronomers used a technique called gravitational microlensing (1) to find the planet, a method that can potentially find planets one-tenth the mass of our own.

The gravitational microlensing technique, which came from Einstein's General Theory of Relativity, relies upon observations of stars that brighten when an object such as another star passes directly in front of them (relative to an observer, in this case on Earth). The gravity of the passing star acts as a lens, much like a giant magnifying glass. If a planet is orbiting the passing star, its presence is revealed in the way the background star brightens. A full explanation of the technique follows this release.


The world's first optical pacemaker is described in an article published today in Optics Express. A team of scientists at Osaka University in Japan show that powerful, but very short, laser pulses can help control the beating of heart muscle cells.

"If you put a large amount of laser power through these cells over a very short time period, you get a huge response," says Nicholas Smith, who led the research. The laser pulses cause the release of calcium ions within the cells, Smith explains, and this action forces the cells to contract.

This technique provides a tool for controlling heart muscle cells in the laboratory, a breakthrough that may help scientists better understand the mechanism of heart muscle contraction.