... Credit: NASA , JPL , Space Sciences Institute Explanation: What's causing unusual jagged shadows on Saturn's rings? ... As a result, Saturn's moons now commonly ca s t long shadows onto the rings . ... Now Saturn's rings have been known to be made of particles for hundreds of years , but these particles have so far escaped direct imaging. ... Publications with keywords: Saturn - saturn rings . Publications with words: Saturn - saturn rings . ... Prometheus Creating Saturn Ring Streamers . ...

... The first task assumes the searching for chemical composition and sizes of particles which give the wavelength dependence of the extinction efficiencies close to the observed dependence of . Figure 7: Wavelength dependence of the extinction efficiency factors for homogeneous spherical particles of different sizes consisting of astronomical silicate and amorphous carbon. The dashed segment shows the approximate wavelength dependence of the mean galactic extinction curve at optical wavelengths. ...

... Ah ha~ Once I questioned, ?what is systematic error?? (see [Q] systematic error. Thanks to L. Lyons? work discussed in [ArXiv] Particle Physics , I found this paper, titled Systematic Errors describing the concept and statistical inference related to systematic errors in the field of particle physics. ... Tags: coverage , Heinrich , likelihood , Lyons , nuisance parameter , objective priors , p-value , particle physics , statistical error , subjective priors , systematic error . ...

... The TRACE images may be used without restrictions in publications of any kind. ... These two images, taken on 18 November 2000 at 15:54UT and 16:11UT, respectively, show such an event: the red circle in the image to the left shows a region where many loops are cooling, with bright loop tops (the intensity scales with the square root of the image to reduce the dynamic range). ... See also a collection of images related to the Sun, other cool stars, and solar-terrestrial effects . ... Images | ...

... We proposed that information retrieved from the local surface photometric behavior of the Moon could be used for guiding the remote sensing analyses of specific geological targets. ... The value of the difference of intensities mentioned above may be used as a photometric parameter I of the local surface roughness. ... 7] Apollo 11 Prelim. ... Figure 5 represents the diagram of relationship between photometric roughness parameter and local thorium content in different lunar regions. ...

Lectures . ... Home Lectures Lecture Series 2010-2011 Lecture Series 2010-2011 ? Particle Physics at the LHC and Cosmology? by Michael Tuts . ... Lecture Series 2010-2011 . ... Beyond New York City . ... Observing Resources for Amateur Astronomers - Part 1: Beginning Observers . ... A History of the First Forty Years of the Amateur Astronomers Association . ... Amateur Astronomers Medal . ... 2016 Amateur Astronomers Association of New York Designed by Press Customizr Powered by . ...

... Before the modern era of technological astronomy, to know anything about the Universe beyond our planet we relied on light. ... Historically the two rival ideas were that light was either a stream of tiny bullet-like particles or a wave wobbling its way through space. ... The light we see (visible light which is not the tautology it sounds) is only part of the electromagnetic spectrum, a great sweep of radiations which also includes radio, infra-red, ultra-violet, x-rays and gamma rays. ...

... Mars . ... Mars rover Opportunity examines clay clues in rock . ... The pale rock in the upper center of this image, about the size of a human forearm, includes a target called "Esperance," which was inspected by NASA's Mars Exploration Rover Opportunity. Data from the rover's alpha particle X-ray spectrometer (APXS) indicate that Esperance's composition is higher in aluminum and silica, and lower in calcium and iron, than other rocks Opportunity has examined in more than nine years on Mars. ...

... We present an analysis of an optical blue spectrum of the pulsating helium star V652 Her (=BD+13 3224$) in order to determine its effective temperature, surface gravity and chemical composition. ... The surface composition is characterised by abundances of nH=0.009, He=0.988, nC~0.000040, nN=0.0025 and nO=0.00010 (number fractions). ... If V652 Her was formed by the merger of two white dwarfs, its surface composition demands that they should both be helium white dwarfs. ...

... IS gas + dust = cosmic abundance [X/H]g + [X/H]d = [X/H]cosmic 5 elements: C, O, Mg, Si, Fe Gas: absorption lines Dust : IS extinction curves Abundances : Reference, cosmic, interstellar , solar COSMIC Sun 06.08.2008 , 12-30 ISM-SAO 5 Interstellar dust grains consist of five the most «important» elements: C, O ­ primary Units: Mg, Si, Fe ­ major ... ApJ 641, 327, 2006 (STIS) + Fitting () 06.08.2008, 12-30 ISM-SAO 62 c2 c3 c4 06.08.2008, 12-30 ISM-SAO 63 06.08.2008, 12-30 ISM-SAO 64 ...

... GCR and SCR are primary cosmic rays. 10-15 years after the discovery of cosmic radiation (1919) there emerged two main avenues of investigation in the physics of cosmic rays (CR): 1) nuclear - elucidation of the origin of elementary particles and nuclear interactions; and 2) astrophysical (space physics) - solution of the problem related to the origin and variations (changes in intensity) of CR. ... Besides, the CR flux in interplanetary space is, strictly speaking, not isotropic. ...