... Credit: STS-82 Crew , NASA Explanation: In low Earth orbit there is not enough atmosphere to diffuse and scatter sunlight, so shadows are black and the sky is dark - even when the Sun shines. The harsh lighting produced this dramatic effect as mission specialist Gregory Harbaugh photographed colleague Joseph Tanner during their second spacewalk to service the Hubble Space Telescope in February 1997. ... February . ... Publications with keywords: Sun - space shuttle - astronaut - dark - sky . ...

Authors: V.A. Marsakov , Yu.G. Shevelev , . Journal: 1988, Astron Zh. ... Absolute magnitudes, metallicities, effective temperatures, surface gravities, distances, and tangential velocities are calculated for 5498 F stars with homogeneous data on uvby photometry and proper motion, and placed within 80 pc from the Sun. Components of space velocities, eccentricities of galactic orbits, perigalactic and apogalactic distances, and maximal remotness from galactic plane are presented for 1787 stars. ...

... The main field of my investigations is stellar spectrophotometry. As a result of scientific activity of our group spectrophotometric catalog was created including energy distribution data on 900 stars in the range 3200-7600AA and 250 stars in the range 6000-10800AA (Voloshina et al., Spectrophotometry of Bright Stars, ed. I.N.Glushneva, 1982, Moscow, Nauka, in Russian). ...

New reduction of minor planets photographic plates obtained with Pulkovo Normal Astrograph A.A. Berezhnoy Pulkovo Observatory of RAS, Saint-Petersburg, Russia Minor Planet observations at Pulkovo Periodical observations of 14 bright asteroids named Selected Minor Planets (SMP) were performed at Pulkovo since 1948 within the international framework started by works of B.V. Numerov and D. Brouwer. ... 108 133 113 74 124 67 97 88 14 84 64 5 20 19 Epochs (YYYY.MM) 1200 Mean values of total obs. ...

... Radio astronomical tests of the engineering model of the space radio telescope (SRT) were completed in Pushchino - see Results . ... Monitoring of the development of the upgrade on-board 1.35-cm receiver (R-SRT-1.35 cm): . ... EM Engineering Model . ... OHCFS-SRT Space Radio Telescope On-board Heterodyne and Clock Frequency Synthesizer set . OHFS-SRT Space Radio Telescope On-board Hydrogen Frequency Standard . ORFS-SRT Space Radio Telescope On-board Rubidium Frequency Standard . ...

... We have measured this "redshift" for the pink black holes, and allowed for it in our calculations. ... We see this effect in the emission from gas around these pink black holes, but it is far too small an effect to account for the pinkness. Thus the swirling motions of gas around or into the black holes cannot produc the colour. ... At first we thought that these things were normal blue black holes hidden behind clouds of interstellar dust, that absorbed the blue light and made them appear pink. ...

To main of Laboratory . The research work and design of optical and optical-electronic devices are carries out by laboratory staff: . ... Lens: . ... In the layout 1 prism systems perform functions of dispersive element, corrector of aberrations, optical reducer. ... Spectral range 200 - 400 nm; . ... Back Forward . ... The main corrector's function are compensation of field aberrations of the main spherical mirror of a telescope (diameter of 600 mm, f'=1200 mm) and increase aperture ratio. ...

... 8 February , 2014 SAI seminar (Ryde et al 2010) 5 Thermal emission from GRB jet progenitor observer photon jet Photosphere (=1) · · · · Photons are not produced at the photosphere We have to calculate radiative transfer We need to know where the photons are produced We construct the expression for effective optical depth in relativistic flow considering random walk process in relativistic flow SAI seminar 6 8 ... 8 February, 2014 SAI seminar 28 ...

You Can't Make Stellar Images Brighter . Articles | ... Did you know that when you look at a non-stellar object through a telescope that it's usually dimmer than looking at it with your naked eye? ... The light enters the eye through the cornea and passes through the pupil which is the opening of the iris. ... Our own pupil effectively stops this large telescope to 700mm, so the image is not any brighter than in the 27.6" telescope and no brighter than the naked eye view!! ... www.astronomy.net . ...

... Bad Astronomy . ... Bitesize Astronomy . ... Keep Bad Astronomy close to your heart, and help make me filthy rich. ... When Venus is on the far side of the Sun, we see the entire near side lit by the Sun. ... When it is on the near side of the Sun, it shows a beautiful thin crescent, because it is between us and the Sun and we see the mostly unlit dark half. ... To see this for yourself, draw a circle one centimeter across, then, next to it, draw a circle 6 centimeters across. ... 2008 Phil Plait. ...

... This program was created for correlating chosen regions in the series of fts images. ... Chosen regions' . ... In this section the program counts the integral for each region of the grid for each image. ... As a matter of fact, the integral is total brightness of the region and it is counted by 'int_tabulated' IDL function. ... In addition, the program will show the count of the regions which correlate with the corresponding region (the brighter region means the bigger count) and its contour. ...

... Fitting the observed dependence includes calculations of the polarization cross-sections averaged over particles orientation and size distribution, their normalization and the comparison of obtained dependencies with Serkowski's curve representing observational data for a chosen star. ... Variations of the polarization factors with wavelength are shown in Fig. 16 for homogeneous spheroidal particles with PF orientation. ... The distinction between prolate and oblate spheroids is also clearly seen. ...

... Reflection nebulae, like the one seen around the Pleiades star cluster, provide natural laboratories for the study of this scattering phenomenon through the measurement of nebular brightness at various wavelengths. ... In the Pleiades this is accomplished with the aid of 21cm neutral Hydrogen emission maps and interstellar absorption spectra toward stars in the region, which together constrain the scattering geometry. ...

... Tonight's Sky . ... The Magazine . ... Observing . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... Bright planets meet at dusk . ... Astronomy magazine subscribers can read the full article for free. ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter....

... 8, ``Celestial Mechanics'', 2002 Earth penumbra effects on AES motion taking into account the refraction and the extinction of the light in the atmosphere A. M. Fominov Institute of Applied Astronomy, St. Petersburg, Russia The perturbing acceleration F of the Artificial Earth Satellite (AES) due to the solar ... In step 1, the table of the shadow function values with the angle distances d between the solar disk and the earth disk edge may be calculated. ...

November 2006 Astronotes 1 Candles in the Dark Image Credit: Wikipedia.org By Colin Johnston, Science Communicator Since the mid-ninteenth century astronomers have used the principle of parallax to measure the distance to other stars. ... How then can we tell, for example, that M31, the galaxy in Andromeda, is 2.2 million light years away? It would be straight-forward to tell how far away a star was if it was exactly the same brightness as our own Sun. ...

On April 14, 2000 UT a series of Shack-Hartmann measurements were made at varying altitudes. ... The tilts and sags shown are those given by the normal Shack-Hartmann analysis. ... Without this feedback, off-telescope tests showed positioning errors on the order of 10 arcseconds in the secondary mirror position. ... Tilt M2 Bk by X" . ... The coefficients m1 through m3 need to be added to those that are currently in the TCC to correct for the secondary translation with respect to the primary. ...

Processing the Viking Orbiter Images . ... Contrast Enhancement . ... Image Processing of Images of the "Face on Mars": A Cautionary Tale . ... In the figures below, the general flow of processing for Viking Orbiter data is outlined, illustrated with the best two images of the "Face"(Figure 1). ... Figure 1: Raw (top) and contrast-enhanced raw (bottom) enlargements of 035A72 (left) and 070A13 (right). ... Figure 3: Increasing the contrast of the "face" images (035A72 (left) and 070A13 (right)). ...

... Развивающая игрушка Лягушка Bright Starts привлечет ребенка красочным видом, подарит новые ощущения и вскоре станет любимой игрушкой, приятной и веселой. ... Цвет: розовый . ... Цвет: Коричневый . ... Цвет: натуральный . ... Кружка имеет силиконовую крышку оранжевого цвета с прорезью для питья. ... Цвет: синий . ...

QED calculations of H2 molecule Vladimir A. Yerokhin St. Petersburg State Polytechnical University in collaboration with Krzysztof Pachucki Warsaw University FFK 2013, Pulkovo, St. Petersburg, October 7-11 Do we need QED for H2? ... 150, 51 (2011) An order of magnitude in precision every 14 years QED : -0.1964 (9) 5, 3039 (2009) Theory: J. Chem. ... Wave function is represented by a linear combination of basis functions Choice of the basis functions: · · Explicitly correlated basis set. ...