Scientists have developed a novel method to calculate the distances to stars, and it could be useful in helping map the size of galaxies. The study is published in the Monthly Notices of the Royal Astronomical Society.
The researchers from the University of Cambridge examined what are known as “stellar twins.” These are stars that are identical, with exactly the same chemical composition, which can be worked out from their spectra – the type of light they emit. If they were both placed at the same distance from Earth, they would shine with equal brightness.
So the team realized that if the distance to just one of the stars was known, the other could be calculated relatively easily based on how brightly it was shining. The dimmer it is, the further away it is, and vice versa. The method can be used to accurately measure the distance.
“It’s a remarkably simple idea – so simple that it’s hard to believe no one thought of it before,” said lead author Dr Paula Jofre Pfeil, from Cambridge’s Institute of Astronomy, in a statement. “The further away a star is, the fainter it appears in the sky, and so if two stars have identical spectra, we can use the difference in brightness to calculate the distance.”
Read more ~ IFL Science
Photo credit: RealCG Animation Studio. Shutterstock.
Ever see an antacid dissolve in water…in space? Read more via io9.
First imaged in 1989, red sprites are a ghostly phenomenon that occur at high altitudes above thunderstorms. Photographed here by ESO Photo Ambassador Petr Horálek, the unmistakable tendrils of multiple red sprites are spotted approximately 600 kilometres away from ESO’s Paranal Observatory above distant thunderclouds.
To capture multiple sprites in one image, two exposures were combined. The upper sprite occurred nearly 21 minutes before the lower one.
In the foreground sits a lone 1.8-metre Auxiliary Telescope, part of ESO’s Very Large Telescope (VLT).
Credit: P. Horálek/ESO
Researchers at Duke University have developed a light-emitting device that can be switched on and off up to 90 billion times per second. This 90 GHz is roughly twice the speed of the fastest laser diodes in existence, potentially offering a whole new level of optoelectronic computing. Central to the technology are the infinitesimal crystal beads known as quantum dots.
The computing devices we’re used to are based on shuttling electrons around via wires and switches. This has worked out pretty well through the history of computing, but electronics have limits, both in speed and in scale. Optoelectronics swap out electrons for pure light: photons. A computer based on information carried via photon is just by definition optimal, offering the literal fastest thing in the universe. Other advantages over electronic systems: less heat, less power, less noise, less information loss, less wear.
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Reid Wiseman Vines: That’s not the Sun, it’s the Moon setting on a gorgeous night.
Associated Press
GENEVA — Physicists on the team that measured particles traveling faster than light said Friday they were as surprised as their skeptics about the results, which appear to violate the laws of nature as we know them.
Hundreds of scientists packed an auditorium at one of the world’s foremost laboratories on the Swiss-French border to hear how a subatomic particle, the neutrino, was found to have outrun light and confounded the theories of Albert Einstein.
“To our great surprise we found an anomaly,” said Antonio Ereditato, who participated in the experiment and speaks on behalf of the team.
An anomaly is a mild way of putting it.
Going faster than light is something that is just not supposed to happen, according to Einstein’s 1905 special theory of relativity. The speed of light — 186,282 miles per second (299,792 kilometers per second) — has long been considered a cosmic speed limit.
The team — a collaboration between France’s National Institute for Nuclear and Particle Physics Research and Italy’s Gran Sasso National Laboratory — fired a neutrino beam 454 miles (730 kilometers) underground from Geneva to Italy.
They found it traveled 60 nanoseconds faster than light. That’s sixty billionth of a second, a time no human brain could register.
“You could say it’s peanuts, but it’s not. It’s something that we can measure rather accurately with a small uncertainty,” Ereditato told The Associated Press.
If the experiment is independently repeated — most likely by teams in the United States or Japan — then it would require a fundamental rethink of modern physics.
“Everybody knows that the speed limit is c, the speed of light. And if you find some matter particle such as the neutrino going faster than light, this is something which immediately shocks everybody, including us,” said Ereditato, a researcher at the University of Bern, Switzerland.
Physicists not involved in the experiment have been understandably skeptical.
Alvaro De Rujula, a theoretical physicist at CERN, the European Organization for Nuclear Research outside Geneva from where the neutron beam was fired, said he blamed the readings on a so-far undetected human error.
If not, and it’s a big if, the door would be opened to some wild possibilities.
The average person, said De Rujula, “could, in principle, travel to the past and kill their mother before they were born.”
But Ereditato and his team are wary of letting such science fiction story lines keep them up at night.
“We will continue our studies and we will wait patiently for the confirmation,” he told the AP. “Everybody is free to do what they want: to think, to claim, to dream.”
He added: “I’m not going to tell you my dreams.”
One sheet, 15 centimetres in diameter and a few tenths of a millimetre thick can store as much as 1 F, which is similar to the supercapacitors currently on the market. The material can be recharged hundreds of times and each charge only takes a few seconds.
It’s a dream product in a world where the increased use of renewable energy requires new methods for energy storage – from summer to winter, from a windy day to a calm one, from a sunny day to one with heavy cloud cover.
”Thin films that function as capacitors have existed for some time. What we have done is to produce the material in three dimensions. We can produce thick sheets,” says Xavier Crispin, professor of organic electronics and co-author to the article just published in Advanced Science.
Other co-authors are researchers from KTH Royal Institute of Technology, Innventia, Technical University of Denmark and the University of Kentucky.
The material, power paper, looks and feels like a slightly plasticky paper and the researchers have amused themselves by using one piece to make an origami swan – which gives an indication of its strength.
The structural foundation of the material is nanocellulose, which is cellulose fibres which, using high-pressure water, are broken down into fibres as thin as 20 nm in diameter. With the cellulose fibres in a solution of water, an electrically charged polymer (PEDOT:PSS), also in a water solution, is added. The polymer then forms a thin coating around the fibres.
”The covered fibres are in tangles, where the liquid in the spaces between them functions as an electrolyte,” explains Jesper Edberg, doctoral student, who conducted the experiments together with Abdellah Malti, who recently completed his doctorate.
The new cellulose-polymer material has set a new world record in simultaneous conductivity for ions and electrons, which explains its exceptional capacity for energy storage. It also opens the door to continued development toward even higher capacity. Unlike the batteries and capacitors currently on the market, power paper is produced from simple materials – renewable cellulose and an easily available polymer. It is light in weight, it requires no dangerous chemicals or heavy metals and it is waterproof.
The Power Papers project has been financed by the Knut and Alice Wallenberg Foundation since 2012.
”They leave us to our research, without demanding lengthy reports, and they trust us. We have a lot of pressure on us to deliver, but it’s ok if it takes time, and we’re grateful for that,” says Professor Magnus Berggren, director of the Laboratory of Organic Electronics at Linköping University.
The new power paper is just like regular pulp, which has to be dehydrated when making paper. The challenge is to develop an industrial-scale process for this.
”Together with KTH, Acreo and Innventia we just received SEK 34 million from the Swedish Foundation for Strategic Research to continue our efforts to develop a rational production method, a paper machine for power paper,” says Professor Berggren.
Power paper – Four world records
Highest charge and capacitance in organic electronics, 1 C and 2 F (Coulomb and Farad).
Highest measured current in an organic conductor, 1 A (Ampere).
Highest capacity to simultaneously conduct ions and electrons.
Highest transconductance in a transistor, 1 S (Siemens)
Publication:
An Organic Mixed Ion-Electron Conductor for Power Electronics, Abdellah Malti, Jesper Edberg, Hjalmar Granberg, Zia Ullah Khan, Jens W Andreasen, Xianjie Liu, Dan Zhao, Hao Zhang, Yulong Yao, Joseph W Brill, Isak Engquist, Mats Fahlman, Lars Wågberg, Xavier Crispin and Magnus Berggren. Advanced Science, DOI 10.1002/advs.201500305
Linköping University
* (You look inside...) * (Inside the joke book is a quantum physics book.)
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