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Partial blue Moon eclipse on 31 Dec 2009

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Just before the end of 2009 we ware witness of the second full Moon of December named a Blue Moon. But only 3 hours before the New Year the Nature was present a follow phenomenon for us as a partial lunar eclipse. If we believe of superstitions or myths now is the moment to expect a lot of surprises from 2010.
 Partial Blue moon  eclipse

Merry Christmas and Happy New Year

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Wish you all a Merry Christmas and a Happy New Year

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.


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.

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.

Stellar classification

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In astronomy, stellar classification is a classification of stars based on its spectral characteristics

IDL Power Visualization and Analysis Ver. 7.0.6

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 On 12 Apr 2009 we have installed IDL Power Visualization and Analysis Ver. 7.0.6 at the National Astronomical Observatory Rozhen.

The software licensing was funded by BG NSF grant NIK – 05

Total solar eclipse 2009

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Next total solar eclipse will be on 22 July 2009.

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