In ancient times the solar system was thought to be the whole Universe, so the study of planetary motions was cosmology. ... The planets other than the Moon and Sun generally move West to East through the stars, but occasionally stop and move in the opposite direction ( retrograde motion). In order to explain the retrograde motion of the planets, the geocentric model of the Solar System shown above puts the planets on small circles called epicycles . ...

... 142,800 Mean density (kg/m^3) .. ... 5.203 Rotation period (length of day in Earth hours).. 9.8 Revolution period (length of year) (in Earth years). 11.86 Obliquity (tilt of axis) (degrees).. 3.08 Orbit inclination (degrees).. 1.3 Orbit eccentricity.. 0.048 Mean surface temperature (K)........................ 120 (cloud tops) Visual geometric albedo.. 0.44 Atmospheric components.............................. 90% hydrogen, 10% helium, .07% methane Rings.. ...

... ARTICLE: The Adventurous Search For The Astronomical Unit . ... Kepler himself had suggested to use the rare occasions of Venus transiting (crossing) the solar disk to measure our distance to the planet. ... Due to the orbital inclination of Venus against the ecliptic of 3.5°, a Venus transit is so rare that it happens only at intervals of 121.5 years, 8 years, 105.5 years, 8 years and so on. ... Crabtree witnessing the transit of Venus 1639 . ... Transits of Venus - The Quest for the Solar Parallax...

... HST . ... Hubble Heritage Project . ... Science Blog . ... Meetings/Workshops . ... 2016 Spring Symposium . ... HST Calibration Workshops | ... March 31 - April 1, 2009 . ... 2010 Hubble Fellows Symposium . ... 2010 HST Calibration Workshop . ... 2005 HST Calibration Workshop ( Proceedings ) . ... 2002 HST Calibration Workshop ( Proceedings ) . ... Hubble's Science Legacy: Future Optical-Ultraviolet Astronomy from Space Workshop . ... STScI/ST-ECF Workshop: Science with HST II (Proceedings only.) ...

. Solar System Radar Research . Proposal on Georing Radar Survey . 4179 Toutatis . 6189 Golevka . 33342 (1998 WT24) . Radar Investigations of Comets . Interior Planets . Don P. Mitchell (JPL, USA). Radio Science and Venus . Main-Belt Asteroids . Planetary Satellites and Rings . Dedicated Radar Telescope . Asteroid's Moons: Discovery by Radar . European Near-Earth Object Radar . USSR – United Solar System Radar . © IRE RAS 1996-200 8

... Contents . ... Sidereal time . ... Mean longitude of the Moon, mean elements of the Moon's orbit and equator . ... Ephemeris for physical observations of the Sun . ... Ephemeris for physical observations of the Moon . ... Matrix elements for conversion to CIRS . ... Conversion of mean time to sidereal time (with accuracy 0.01 s ) . ... Conversion of sidereal time to mean time (with accuracy 0.01 s ) . ... Conversion of mean time to sidereal time (with accuracy 0.001 s and 0.0001 s ) . ...

Hello from Japanese crews. ... Earth . ... My first name is Earth. What is your name? I will help Japanese - English translation from The Earth.) ... My name is Moon. ... I am a boy. Are you a boy or a girl? I am 7 years old. How old are you? My hobby is swimming. What is your hobby? Bye. ... My name is Mercury . I am a girl. ... My hobby is ride a wheel bicycle. ... My name is Jupiter. ... My hobby is playing dodge ball. ... My name is Venus. ... Bye, Kae . ...

... 3 ­ Sternberg State Astronomical Institute, Moscow, :jeanna@sai.msu.ru The graphic method of the analysis of an arrangement of linear structural elements on geographical and geological maps of continents (A.V.Dolitsky, [1]) has allowed to find out global stress fields of the past and among them one which directions (the main normal and maximal tangents) describe more than 80 % of all linear elements of a relief. ... The found poles share program way on density of an arrangement on 3-4 groups. ...

... StarCity, Moscow Region. The Star City situated near Moscow hosted the solemn event devoted to meeting with the crew of the 11th Expedition to the International Space Station (ISS-11): Russian cosmonaut Sergei Krikalev and NASA astronaut John Phillips, as well as Gregory Olsen, US citizen, another participant of this space flight, who had returned with them to Earth and worked on the ISS under the 9th Visiting Crew (VC-9) Program. ... Official WEB-site of S.P.Korolev RSC Energia . ...

Michele Bannister . Other research . ... The mutual events of Haumea . The dwarf planet Haumea is the parent of a collisional family that includes its two moons, Hi'iaka and Namaka. ... The arid and windswept McMurdo Dry Valleys of Antarctica are carpeted with the polygons of patterned ground , a geological formation that is also seen on the northern plains of the planet Mars. ... I worked to understand the influence that buried masses of ice have on the development of patterned ground. ...

Planetary Illumination, and Its effect on Climate Models of Earth-like Exomoons Duncan Forgan1,2 , Vergil Yotov1 1 2 SUPA, Institute for Astronomy ... Compared to an Earth-like planet, there are several extra sources and sinks of energy available to an Earth-like exomoon, including: Tidal Heating Planetary Illumination (thermal flux and reflected starlight) Eclipses of the star by the planet (acts as a sink) Circumstellar HZ - Zero Moon ...

... Pre-university education . ... Samara region . ... A small spacecraft Aist-2D , developed by the scientists of Samara State Aerospace University (SSAU) and the experts of the Rocket and Space Centre Progress will see from outer space what is hidden under the thick top of trees and below the Earth's surface. The radar equipment was installed on Aist-2D , which was delivered to the space launcher complex Vostochniy on January 22. ... Tomography of the Earth's ionosphere will also be carried out. ...

... Main . ... April 2016 . ... December 2015 . November 2015 . October 2015 . September 2015 . August 2015 . July 2015 . June 2015 . May 2015 . April 2015 . March 2015 . February 2015 . January 2015 . December 2014 . November 2014 . October 2014 . September 2014 . August 2014 . July 2014 . June 2014 . May 2014 . April 2014 . March 2014 . ... December 2013 . ... April 2013 . ... December 2012 . ... April 2012 . ...

The following activities are included in the Universe at Your Fingertips guide. ... Clicking on each activity will take you to a "reviews" page where you can post a review, or read reviews posted by others who have used the activity. ... Activity Online . ... MOON AND PHASES . ... Observing Phases and Features . ... Modeling Moon Phases . ... SUN AND SEASONS . ... Observing the Sun Safely . ... Observing Where the Sun Sets . ... Making Pictures of Motion . ... Morning Star and Evening Star . ...

IV International Astronomy Olympiad . ... Text of these problems is available also . ... To solve every problem you may use constants and well-known values you know by heart. ... The apparent diameter of the Moon, as seen from the Earth, is 31'. ... Can you observe a star with magnitude . ... Consider the stars as black bodies. ... Estimate the diameter of a black hole constructed using this patent from a ship with the mass of 5000 tn (1 tn = 1000 kg). ... What stars would you observe this nigth? ...

... 2006 . ... Comparison of total ozone distribution in the high latitudes of both hemispheres SCAR XXIX Open Science Conference, 2006, 12-14 July, Hobart, Australia - Abstract Volume. ... Analyses of spectra, stability and eigenmode transverse small-scale oscillations in the inner Earth magnetosphere. 6th Open Conference of Space Projects Evpatoriya, September 2006, Abstracts . ... Ps6 pulsations in the Earth magnetosphere. 5th Open Conference of Space Projects Evpatoriya, September 2005, Abstracts . ...

... Prof. N.N. Kiselev . ... Dr. V.K. Rosenbush . ... Kiselev N.N., Velichko F.P. (1998) Polarimetry and photometry of comet C/1996 B2 Hyakutake. ... PDF file ] . Kiselev N.N., K. Jockers, V.K. Rosenbush et al. ... Kiselev N.N., Jockers K., Rosenbush V.K. (2002) Comparative study of the dust polarimetric properties in split and normal comets. ... Rosenbush V.K., Kiselev N.N., Velichko S.F. (2002) Polarimetric and photometric observations of split comet C/2001 A2 (LINEAR). ...

... Конференц?я "Р?внодення 2016". ... Киевский клуб любителей астрономии "Астрополис" > . ... Астрософт (Модератор: tlgleonid ) > . Moon in Google Earth . ... Бердянское общество любителей астрономии "ОРИОН" . ... Астрогоризонт - новости NASA на русском языке . ... NASA . ... предыдущая тема следующая тема . ... Видимо NASA и Google решили к юбилею полета человека на Луну сделать подарок пользователям Google Earth добавив в сервис спутник нашей планеты, со всевозможными фотографиями и 3D моделями . ...

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... ST-ECF . ABOUT ST-ECF . ... After an initial agreement between NASA and ESA in 1977 and following Hubble's more than twenty years in space and 110,000 orbits of the Earth, the aim of this conference is to celebrate the huge contributions made by the Hubble observatory to our knowledge and understanding of the Universe. ... David Southwood . ... Robert O'Connell . ... Robert O'Dell . ... Questions and information: HST3@stecf.org . ... Maintained by HST 3 Webmaster <HST3@stecf.org> . ...