... Discussion of Declination Drive Design . ... It is held in my personal stock of parts to replace a drive that might go out of service for some reason on one of the two LX200 telescopes that I am responsible for keeping in good repair.  ... The photocells detect light from a pair of small lights through the encoder mask and encoder wheel encased in the gear box housing. ... In one case of declination drive runaway, the cause was breaking of one of the leads to one of the photocells.  ... All fixed!! ...

The results of a search for ultrarapid variability of galactic water maser sources at the wavelength 1.35 cm on a timescale of several minutes to 1 h are reported. A special observational technique was developed. ... Among those, several sources that have shown such variability were found. ... Clear evidence for such a variability type was found in at least two sources: W49N and W33B. Variability of this kind displays itself only in certain states of the water masers. ...

... We are from Siberia, city Krasnoyarsk. ... We don't know the meaning of the word "Siberia" in our time. ... But we believe that this word comes from the tatarian language and means "sleeping . ... One of the streets is named after voivode Andrey Dubenski who put ashore a detachment of 300 cossaks in spring of 1628 right where the little but rough Kacha river falls into the Yenisei. ... This word of Tungus origin "ionessi" means "high water".Some windows of our school face at the Yenisei. ...

... ARTICLE: Ein aussergewЖhnlicher Abend mit John Dobson in Saarlouis . ... John L. Dobson, der Erfinder des weltbekannten Dobsonteleskops und BegrЭnder der „Sidewalk Astronomers“ zu Beginn der 60er Jahre in San Francisco Эberraschte sein Publikum am vergangenen 14.September 2006 bei einem Vortrag in Saarlouis mit seinem direkten und unverblЭmten Stil. ... Hierzu braucht man Oeffnung, was Anfang der 60er Jahre im Amateurbereich fehlte. ... Ein aussergewЖhnlicher Abend mit John Dobson in Saarlouis . ...

The new view on the population of Galactic open clusters A.E.Piskunov1, N.V.Kharchenko2, S.RЖser3, E.Schilbach3, R.-D.Scholz4 1 2 3 4 Institute of Astronomy, Moscow, Russia Main Astronomical ... Observatory, Kiev, Ukraine Astronomisches Rechen-Institut, Heidelberg, Germany Astrophysikalisches Institut Potsdam, Germany What are open clusters and what do they teach us Groups of Population I ... Cluster complexes: OCC-1 = Gould's Belt cluster complex? ...

DISCLAIMER: The larger the aperture, the more light a telescope will gather and the fainter the object you can see. Here is a range of magnitudes you might expect to see. Given excellent sky conditions and good optics, a well trained eye can sometimes add up to 0.8 magnitude to these values. Limiting Magnitude depends on much more than the instruments aperture. ... One formula is for aperture in inches the other is for aperture in millimeters. ... Aperture (inches) . ... 15.2 . ...