Fire news from Mt. Wilson Observatory

Mt. Wilson Observatory: US Forest Servie Fire Dispatch has informed Hal McAlister, director of the Mt Wilson Observatory that as of 9:40 PDT this morning, ground crews were back at the Observatory. As of 8:00 am, air tankers were back in operation.

The dispatcher expressed his opinion that as long as the fire continues to press the mountain from one direction “you are going to make it.”

Furthermore, there is some light rain developing in places in the Los Angeles basin, and there is a possibility for some thunderstorm activity that could lead to dry lightning. The humidity is up and the temperature is a bit lower, so, all in all, things are looking more promising than they have in the last few days.

View from the observatory as of noon (PDT), Tuesday 1 September.

The latest news can be found here.

Meanwhile, the LA Times takes a look back at the history of the Mt. Wilson observatory. Astronomer Edwin Hubble for example, used the then-groundbreaking 100-inch Hooker telescope, to make two of the most surprising scientific discoveries of the 20th century: The universe was far larger than anyone imagined and that it was expanding.

Caltech solar labs

latimes.com: In a lab in Caltech, Harry Atwater holds up a plastic panel, a fraction of a millimeter thick. Even in the bright room, the surface’s panel remains jet-dark—absorbing all the light that hits it.

The high-tech material is 10 times more efficient at absorbing light than the regular silicon cells that some homeowners install on their roofs to harvest the energy of the sun.

It is one of several projects that Atwater’s team at Caltech is pursuing in a push to design the next generation of solar cells—ones that are cheap, long-lasting and flexible enough to be practical for homeowners and businesses.

The rush to develop tiny lasers

NPR: Researchers in several laboratories are vying for the claim that they have produced the world’s smallest lasers. The lasers are a thousand times smaller than the diameter of a human hair. Scientists hope they can be used to create even smaller and faster electronics, to study diseases, or possibly even to treat cancer from inside human cells.

Smoothing the way to superior OLED displays

Nanowerk: Electrospray-deposited polymer films can be used to make organic light-emitting diodes (OLEDs) with better characteristics than those made from spin-coated films, according to Yutaka Yamagata of the RIKEN Center for Intellectual Property Strategies, Wako, and colleagues. These researchers have used a novel dual-solvent concept to make the electrospray-deposited films smoother than before, thereby enabling the superior devices to be built.

Related Link
Thin-Film Fabrication Method for Organic Light-Emitting Diodes Using Electrospray Deposition

Why Antarctica is the best stargazing site on Earth

physics theory Today: The search for the best observatory site in the world has lead to the discovery of what is thought to be the coldest, driest, calmest place on Earth. “The astronomical images taken at the site should be at least three times sharper than at the best sites currently used by astronomers,” Will Saunders, of the Anglo-Australian Observatory (AAO) and visiting professor to University of New South Wales (UNSW), who led the study.

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The joint US-Australian research team combined data from satellites, ground stations and climate models in a study to assess the many factors that affect astronomy: cloud cover, temperature, sky-brightness, water vapour, wind speeds and atmospheric turbulence.

The researchers pinpointed a site, known simply as Ridge A, that is 4,053m high up on the Antarctic Plateau. Located within the Australian Antarctic Territory (81.5° S 73.5° E), the site (see picture above) is not the highest point on the Plateau but 144km away from it.

The highest point, called Dome A, is the site of an international robotic observatory and the proposed new Chinese ‘Kunlun‘ base (80.37° S 77.53° E).

Last year, the AAO completed the first detailed study into the practical problems of building and running the proposed optical/infra-red PILOT telescope project in Antarctica. The 2.5-metre telescope will cost over AUD$10million and is planned for construction at the French/Italian Concordia Station at Dome C by 2012.

Ridge A is not only particularly remote but extremely cold and dry. The study revealed that the site has an average winter temperature of − 70°C.

It is also a site that is “so calm that there’s almost no wind or weather there at all,” says Saunders. “Because the sky there is so much darker and drier, it means that a modestly-sized telescope there would equal or be far superior to the best existing observatories on high mountain tops in Hawaii and Chile,” he adds.

Interest in Antarctica as a site for astronomical and space observatories has accelerated since 2004 when UNSW astronomers published a paper in the journal Nature confirming that a ground-based telescope at Dome C, another Antarctic plateau site, could take images nearly as good as those from the space-based Hubble telescope.

Making use of this Antarctic sites will give Australian astronomers a chance to become major partners with Chinese or European efforts to build the first major Antarctic observatory says Saunders.

Related Links
Where Is the Best Site on Earth? Domes A, B, C, and F, and Ridges A and B
Exceptional astronomical seeing conditions above Dome C in Antarctica Nature

More Tests On Local Lorentz Invariance

Any theory of violation of Lorentz invariance now has an even more stringent limit to overcome. A new report published in PRL has tested this to an even greater accuracy[1].

Abstract: We report on the results of a strongly improved test of local Lorentz invariance, consisting of a search for an anisotropy of the resonance frequencies of electromagnetic cavities. The apparatus comprises two orthogonal standing-wave mechanics optical cavities interrogated by a laser, which were rotated approximately 175 000 times over the duration of 13 months. The measurements are interpreted as a search for an anisotropy of the speed of light, within the Robertson-Mansouri-Sexl (RMS) and the standard model extension (SME) photon sector test theories. We find no evidence for an isotropy violation at a 1sigma uncertainty level of 0.6 parts in 10^17 (RMS) and 2 parts in 1017 for seven of eight coefficients of the SME.

We have yet to see such violations.

Zz.

[1] Ch. Eisele et al., Phys. Rev. Lett. v.103, p.090401 (2009).