... Spherical aberration, coma, and astigmatism are also easily observed using the star test. ... Off-axis images are complex. ... Fig. ... Diffraction by a circular aperture as a function of defocus for no aberration Airy Disk 1 wave defocus Less than 1 wave defocus Fig. ... Diffraction by a circular aperture as a function of defocus for third-order spherical aberration Paraxial Focus Small distance inside paraxial focus Moderate distance from marginal focus Immediate neighborhood of marginal focus Fig...

... Regional planning meeting for the Balkan and Black Sea | ... Proposals for a web site of the Regional Network - Information on regional and global activities - Proceedings of this Meeting - Space Weather Alerts for the public - Form for submitting research and observational proposals - Database of scientific data publicly available - Greece provides solar telescope data - Romania provides data on active regions studied with helioseismis holography - Armenia provides access to...

... Precisely one month ago, on 11 July 2009, the last active area of the new solar cycle disappeared from the surface of the Sun. Over the 30 days following this, neither observers on Earth nor devices in space have been able to detect the emergence of any sunspots. ... Therefore, it seems that our star has once again returned to a state of deep solar "winter", following several sparks of activity in May-June 2009. ... To date, this period has lasted 30 days. ...

Клуб Скептиков . ... Имя: надежда, E-Mail: darelvc@gmail.com , Город: Винница . Home Page URL: http://ktonavkusnenkoe.ru . Комментарии: немножко надо поработать над сайтом, как то скучновато. ... Home Page URL: http://www.rosstro-velox.ru/ . ... Home Page URL: http://www.arenda.rosstro-group.ru/ . ... Home Page URL: http://www.vkusnodiet.ru/ . ... Home Page URL: http://cameramania.ru . ... Имя: Твоя мамка . ... Комментарии: Вот такое новое сообщение здесь на сайте скептиков в книге гостей . ...

... Oleg V. Verkhodanov . ... The last few years have changed our view on the evolution of galaxies: the most distant galaxies (i.e. systems having stellar population) have been found at redshift z=6.68 (Chen H.-W., Lanzetta, K. M., Pascarelle, S. 1999, Nature, 398 , 586) and radio galaxy at z=5.19 (van Breugel W., De Breuck C., Stanford S. A., Stern D., Rottgering H., Miley G. 1999. astro-ph/9904272 ). ... Redshifts and age of stellar systems of distant radio galaxies from multicolour photometry data. ...

... The aerospaceplane project dated 29 June 1966 provided for the development of a 115-t orbital system consisting of three winged VTOL reusable aircraft: the 52-t HLA reusable hypersonic air-breathing launch aircraft, designated '50-50'; the RB expendable two stage rocket booster; and the OS manned orbital aerospaceplane, designated '50'. ... ORBITAL AEROSPACEPLANE DIMENSIONS . ... Instead, he came out with an initiative to start up the Buran programme in the USSR as a response to the US Shuttle. ...

... A non-linear relationship is observed between the sky brightness on clear and overcast nights, with a change in behavior near the rural to urban landuse transition. ... The great variation in skyglow radiance observed from site-to-site and with changing meteorological conditions underlines the need for a long-term international monitoring program. he introduction of artificial light has caused an unprecedented disruption to the nighttime environment over large areas of the Earth. ... Data processing...

Please enter the lightcurve file name and period search parameters: . Lightcurve file: . ... Apply the Heliocentric correction and convert all dates to Terrestrial Time (TT)? ... Phase range for plots: -0.5 to 1.0 0.0 to 2.0 0.0 to 1.0 . ... Also, the Heliocentric correction cannot be applied to such lightcurves. ... Two period search methods are currently implemented. ... This period search service is also available at the mirror sites: Mirror 1 , Mirror 2 , Mirror 3 , Mirror 4 . ...