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The Known Universe Scientifically Rendered For All to See

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The Known Universe Scientifically Rendered For All to See

After hovering over Mount Everest and the gorges that plunge to the Ganges, you are pulled through the Earth’s atmosphere to glimpse the inky black of space over Tibet’s high desert. So begins The Known Universe, a new film produced by the American Museum of Natural History that is part of a new exhibition, Visions of the Cosmos: From the Milky Ocean to an Evolving Universe, at the Rubin Museum of Art in New York City. 

Total solar eclipse on 22 July 2009

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 The research team of the Institute of Astronomy, Bulgarian Academy of Sciences realized observations of the total solar eclipse on 22 July 2009 form Tianhungping, China.

Unfortunately, the weather condition was not perfect time for observations and was impossible to receive good photographically information.

 

JET STREAM

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Jet_Str3.JPG

Jet streams are fast flowing, narrow air currents found at the tropopause, the transition between the troposphere (where temperature decreases with height) and the stratosphere (where temperature increases with height),[1] and are located at 10-15 kilometers above the surface of the Earth. They form near boundaries of adjacent air masses with significant differences in temperature, such as the polar region and the warmer air to the south.[2] The path of the jet typically has a meandering shape, and these meanders are one manifestation of Rossby waves. Rossby waves propagate westward with respect to the flow in which they are embedded, which translates to a slower eastward migration across the globe than smaller scale short wave troughs.

How are we calculating sunrise/sunset times

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Sunrise/sunset times are calculated using embedded PHP 5 functions. The almanac module implements the low resolution method for calculating moonrise and moonset outlined in Montenbruck and Pfleger's Astronomy on the Personal Computer (1989). The time displayed in the sunrise/sunset box is the time at which sunrise/sunset were calculated.

proton-proton chain

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p-p 01.jpg

The core makes about 2% of the Sun’s volume (core’s radius is ~1/4 Rסּ) but contains nearly half of its mass. The highest temperature is in the center ~1.55x107 and decreases outwards to 9.42x106 K. The high temperatures and densities provide conditions for the nuclear fusions that power the Sun. Most energy is provided from the three step process of hydrogen to helium conversion (proton-proton chain). A single proton-proton chain yields 26.73 MeV in gamma rays and ~0.5 MeV in two neutrinos.

Solar Structure

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Cross-section of the Sun (SOB)

 
This diagram shows main layers of a solar-type star. Using a neutral filter we can see from the Earth one perfect disk and this is the solar photosphere. Layers under the photosphere are invisible for us. With special instruments and filters there are possibilities to observe some phenomenon from the chromosphere (spicules, filaments, etc.). During total solar eclipses is possible to observe the solar corona.

Comments system is active

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We've enabled the posibility to post comments on blogs, publications and images. Anonymous comments are allowed, but moderated (you can comment, but an administrator must approve your comments). Commenting is posible only for content posted from now on. Old content will be enabled somewhere in time :)

Full circle halo

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Circle rainbow during the dayExtraordinary halo around the Sun was observed on 24 Apr 2009 from the Observatory Rozhen.
This full circle halo was visible during the day. I've never saw it before.
The phenomenon was visible for quiet some time – more than 1 hour.

Site design changes

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Due to user demand we are back to the black/red design, separate Blogs page added.

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