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Researchers go from heaven to Earth in ‘lifeguard’ test

Back in 2002, Stanford University engineers Kevin Montgomery, PhD, and Carsten Mundt, PhD, found themselves bored at a conference in Las Vegas. So they did what you’d expect from any researchers stuck in Sin City with frequent thoughts about life in outer space: They headed to a casino, downed a few cocktails and drew up a plan for the ideal physiological monitor for astronauts.

Weighing Ultra-Cool Stars

Even though astronomers have found several hundreds of very low mass stars and brown dwarfs, the fundamental properties of these extreme objects, such as masses and surface temperatures, are still not well known. Within the cosmic zoo, these ultra-cool stars represent a class of ”intermediate” objects between giant planets – like Jupiter – and ”normal” stars less massive than our Sun, and to understand them well is therefore crucial to the field of stellar astrophysics.

Hottest body outside the sun? It’s Io

The hottest spot in the solar system is neither Mercury, Venus, nor St. Louis in the summer. Io, one of the four satellites that the Italian astronomer Galileo discovered orbiting Jupiter almost 400 years ago, takes that prize. The Voyager spacecraft discovered volcanic activity on Io over 20 years ago and subsequent observations show that Io is the most volcanically active body in the solar system. The Galileo spacecraft, named in honor of the astronomer Galileo, found volcanic hot spots with temperatures as high as 2,910 Fahrenheit (1,610 Celsius).

First direct measurement of the mass of ultra-cool brown dwarf binary

An international team of astronomers using the world’s biggest telescopes have directly measured the mass of an ultra-cool brown dwarf star and its companion dwarf star for the first time. Barely the size of the planet Jupiter, the dwarf star weighs in at just 8.5 percent of the mass of our Sun. This is the first ever mass measurement of a dwarf star belonging to a new stellar class of very low mass ultra-cool dwarf stars. The observation is a major step towards our understanding of the types of objects that occupy the gap between the lightest stars and the heaviest planets.

Quantum dots see in the dark

Researchers have built and tested a device based on nanostructures called quantum dots that can sensitively detect infrared radiation in a crucial wavelength range. The atmosphere is opaque to most infrared, but it is transparent for a narrow ”window” between 8 and 12 microns. Night vision goggles, military target tracking devices and environmental monitors utilize this range of wavelengths.

Pumping energy to nanocrystals from a quantum well

University of California scientists working at Los Alamos National Laboratory with a colleague from Sandia National Laboratories have developed a new method for exciting light emission from nanocrystal quantum dots. The discovery provides a way to supply energy to quantum dots without wires, and paves the way for a potentially wider use of tunable nanocrystalline materials in a variety of novel light-emitting technologies ranging from electronic displays to solid-state lighting and electrically pumped nanoscale lasers.

Studies on electric polarization open potential for tinier devices

Researchers from the U.S. Department of Energy’s Argonne National Laboratory and Northern Illinois University have shown that very thin materials can still retain an electric polarization, opening the potential for a wide range of tiny devices. The researchers found that the ferroelectric phase ? the ability to hold a switchable electric polarization ? is stable for thicknesses as small as 1.2 nanometers, one-billionth of a meter, or a size several hundred thousand times smaller than the period at the end of this sentence.

Fermilab Results Change Higgs Mass Estimate

Scientists have announced new results that change the best estimate of the mass of the postulated Higgs boson from approximately 96 GeV/c2 to 117 GeV/c2. Compared to the previous value, the new value is in better agreement with direct searches – such as those conducted by CERN experiments – that excluded a mass below 114 GeV/c2. In a paper to appear in the June 10 issue of Nature magazine, physicists of Fermilab’s DZero experiment report on results obtained by applying a new analysis technique to data obtained from 1992 to 1996 during Collider Run I at the Fermilab Tevatron, the world’s highest-energy particle accelerator.

Top quark measurements give ‘God particle’ new lease on life

Researchers from the University of Rochester have helped measure the elusive top quark with unparalleled precision, and the surprising results affect everything from the Higgs boson, nicknamed the ”God particle,” to the makeup of the dark matter that comprises 90 percent of the universe. The scientists developed a new method to analyze data from particle accelerator collisions at Fermilab National Accelerator Laboratory, which is far more accurate than previous methods and has the potential to change the dynamics of the Standard Model of particle physics. Details of the research are in today’s issue of the journal Nature.

Gemini Mirror is First with Silver Lining

A silver coating newly applied to the 8-metre mirror of the Gemini South telescope is set to make it the most powerful infrared telescope on the Earth, allowing UK astronomers and their international partners to study in detail the formation of stars and planets. A key measure of a telescopes performance in the infrared is its emissivity (how much heat it actually emits compared to the total amount it can theoretically emit) in the thermal or mid-infrared part of the spectrum. These emissions result in a background noise against which astronomical sources must be measured. Gemini has the lowest total thermal emissivity of any large astronomical telescope on the ground, with values under 4% prior to receiving its silver coating.

Researchers learn to precisely control nanoparticle spacing

Another puzzle solved: Researchers are now able to control precisely the spacing between nanoparticles, a key advance in the genesis of a new class of nanoscale electronics and optics. ”We care about the spacing between the particles because the interactions between them are distance-dependent,” said a lead scientist.. ”If they’re too far apart, the interaction will be weaker, preventing the particles from passing electrons from one to another.”