... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Risks Comparable to NEOs . ... The Increasing Rate of Discovery of Asteroids . ... Comet and Asteroid Collision Probabilities . ... Extreme albedo comets and the impact hazard (PDF Format) . ... Asteroid Impact Animations . ... Workshop on Scientific Requirements for Mitigation of Hazardous Comets and Asteroids - 2002 . ... The Spaceguard Survey Report, 1992 (PDF) . Tsunami from Asteroid/Comet Impacts . ...

Astronomy Picture of the Day . ... 14.05.2007 . ... Credit: NASA , JPL , Doug Ellison Explanation: When passing Earth on your way to Jupiter, what should you look for? ... During Galileo's first Earth flyby in late 1990, it made a majestically silent home movie of our big blue marble rotating by taking images almost every minute during a 25-hour period. ... U. Based on Astronomy Picture Of the Day . Publications with keywords: Earth - Galileo . Publications with words: Earth - Galileo . ...

... Kepler's 3rd Law . 21a.Applying 3rd Law . 21b. Fly to Mars! (1) . 21c. Fly to Mars! (2) . ... For circular orbits around Earth, we found . ... The distance of a satellite from the center of Earth in meters is an inconveniently big number, even before we raise it to the 3rd power. ... The ratio r' = (r / R E ) is the orbital distance measured in units of the Earth's radius. ... 25 638 838) = 5063.5 From this . ... This is the practical form of Kepler's 3rd law for Earth satellites. ...

... 2007 May 14 . Rotating Earth from Galileo . ... Explanation: When passing Earth on your way to Jupiter, what should you look for? That question arose for the robotic Galileo spacecraft that soundlessly coasted past the Solar System's most photographed orb almost two decades ago. ... During Galileo's first Earth flyby in late 1990, it made a majestically silent home movie of our big blue marble rotating by taking images almost every minute during a 25-hour period. ... About APOD | ...

For circular orbits around Earth, we found . ... The distance of a satellite from the center of Earth in meters is an inconveniently big number, even before we raise it to the 3rd power. ... SQRT (25 638 838) = 5063.5 From this . ... T= 5063.5 seconds SQRT(r') 3 = 5063 sec r'SQRT=(r') . This is the practical form of Kepler's 3rd law for Earth satellites. ... International communication satellites are in the equatorial plane of the Earth and have orbits with a 24-hour period. ...

... Comments, Opinions Publications Dnepr Program . Dnepr launch record 17 August 2011. Cluster Launch of Dnepr LV 22 August 2013 KOMPSAT-5 Launch 21 November 2013. Dnepr Cluster Mission 2013 19 June 2014. ... ISC Kosmotras announces signing of a launch contract with T B?TAK Space Technologies Research Institute (T B?TAK UZAY) for injection of RASAT spacecraft - the first Earth observation satellite designed and manufactured in Turkey by Dnepr LV in 2010. ... Dnepr LV Performance . ...

How Precise is the Orbit of (99942) Apophis and how Probable is its Collision with the Earth in 2036? ... At present the orbit of asteroid (99942) Apophis and the forces acting on it are not known with sufficient accuracy to predict with certainty its motion after the close approach to the Earth in April of 2029. As a result of this approach the current heliocentric orbit of the asteroid will be changed by Earth's gravity. ...

... Tonight's Sky . ... Sky this Month . ... space physics . ... The Sky This Week: April 1 - 10 . ... Sky this Week . ... Sky Events . Get to Know the Night Sky . Tour the Deep Sky . Sky Guide . ... Observing springtime deep-sky objects with a large telescope . ... Johns Hopkins University Applied Physics Lab, Laurel, Maryland . ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ...

... Jay Apt (Ph.D.) . NASA Astronaut (Former) . ... PUBLICATIONS: Dr. Apt shared his images and knowledge in the publication Earth in Orbit : NASA Astronauts Photograph the Earth , written in conjunction with NASA scientists Michael Helfert and Justin Wilkinson and published by the National Geographic Society. ... From 1976 to 1980 he was a staff member of the Center for Earth & Planetary Physics, Harvard University, supporting NASA s Pioneer Venus Mission by making temperature maps of Venus from Mt. ...

... xmmtrack . ... xmmtrack is an interactive IDL application that visualizes the orbit and attitude data in an ODF in the form of a 3-D animation sequence. The presented scenery includes an astronomically accurate simulation of the Earth-Sun system plus the actual and predicted trajectory of the XMM satellite on its path around the Earth. ... Please note: XMM's orbit is highly time variable and the predicted orbit will significantly deviate from the actual trajectory if the reference epochs differ. ...

... ATNF Home . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . ... Parkes | ... Cosmic engine for senior students . ... The Sun . The Sun is vital for life on Earth. ... The Sun is a typical star, emitting electromagnetic radiation and particles that influence the Earth . ... In the meantime you can view material on the Sun and its influence on Earth written for the first version of the new syllabus here . ...

... Galileo Probe . The Galileo spacecraft was designed to study Jupiter's atmosphere, satellites, and surrounding magnetosphere for two years. ... From there, Galileo will spend more than five years traveling to Jupiter, where it will become the first spacecraft to make direct measurements from an instrumented probe within Jupiter's atmosphere. ... This image, taken by the Hubble Space Telescope, shows the predicted site at which the Galileo Probe will enter Jupiter's atmosphere on December 7, 1995. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Armagh Planetarium . ... Solar System . ... Moon . ... Space Flight . ... Earth Satellites . ... Concept Spacecraft . ... Monthly Sky Notes . ... This image of Earth (left) and the Moon (right) was taken by the Juno space probe's JunoCam, three weeks after its 5 August launch. (image credit:: NASA / JPL / MSSS) . ... Earth and the Moon form a тАЬdouble planetтАЭ unique in the Solar System. ... Subscribe to Astronotes . ...

... Bad Astronomy . Misconceptions . ... Bad Astronomy : The Moon only shows one face to us because it is not rotating. Better astronomy : The Moon only shows one face because it is rotating, once every time it revolves around the Earth. ... Place the Moon model on the table about 30 centimeters (one foot) away with the X facing the Earth model. ... You'll see that to keep the X facing the Earth model, you have to rotate the Moon model as it goes around the Earth model . ... 2008 Phil Plait. ...

... Our restless globe and its companion. ... A Look at the Motions of the Earth in Space and How They Are Changing . ... Earth's rotation as viewed from above the north and south geographic poles. ... The Earth revolves around the Sun-also counterclockwise viewed from above the North Pole, clockwise viewed from the South Pole-to give us our years (see Figure 2 ). The plane of the Earth's orbit is called the ecliptic (where eclipses happen). ... Earth's orbit as viewed from the north ecliptic pole. ...

... The barycentric corrections computed in 8.7.1 are applied to the event times in a time-sorted QPOE file. ... output files: rp90_out.qp ti apply_bary input qpoe file name: rp90_sti.qp[ time =(1606720.0:1612809.8)] # see Note 1 2 input correction table filename: rp110590_cor.tab output qpoe file name: rp90_out event definition: medium SCC- UTC conversion table is calibrated to SCC 110883482.0000 first qpoe gti time = J.D. 2448062.97604379, SCC 1606720.00000000 last qpoe gti ...

Image credit: Michael Nolan, Arecibo Observatory. These radar images of near-Earth asteroid 2001 SN263 were obtained on 2008 Feb 12 and 13. ... Image from Feb 12 . ... First near-Earth triple asteroid discovered by Arecibo Observatory . ... was discovered this week by astronomers at the sensitive radar telescope at Cornell University?s Arecibo Observatory in Puerto Rico. ... For example, Arecibo has discovered more than half of the near-Earth binary asteroid systems discovered since 1999. ...

Russian SHAREABLE DATA CENTER Institute of Solar-Terrestial Physics SB RAS . ... A most promising problem is to investigate the interaction of two VHF powerful radiowave beams in the ionosphere, whose difference frequency is equal to the plasma frequency in some ionospheric area (that is, the difference frequency is taken in the range 1-8 MHz). ... Two-frequency interaction effects are based on radiowave non-linear mixing, which is rather complicated when describing and modelling the experiment. ...

... 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.. ...

... Pre-university education . ... Samara region . SSAU History . SSAU roadmap . ... Scientists of Samara University (joined SSAU and SSU) began to develop a unified manoeuvring unit for CubeSat-type nanosatellites for the first time in Russia. ... During one of his latest visits to SSAU he proposed to extend capability of the nanosatellites created in Samara University by making a manoeuvring unit and allocated funding to begin work on this topic. ... Nanosatellites of Samara University . ...