... 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 . ...

... Hurricane Paths on Planet Earth . ... The above Earth map shows the path of every hurricane reported since 1851, Although striking, a growing incompleteness exists in the data the further one looks back in time. ... The map also shows that hurricanes never cross -- or even occur very near -- the Earth's equator , since the Coriolis effect goes to zero there, and hurricanes need the Coriolis force to circulate. The Coriolis force also causes hurricane paths to arc away from the equator. ...

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... 2012 May 30 . Looking Back at an Eclipsed Earth . Image Credit: PHL @ UPR Arecibo, NASA , EUMETSAT , NERC Satellite Receiving Station, U. Dundee . Explanation: What's that dark spot on planet Earth? ... The above image of Earth was taken last week by MTSAT during an annular eclipse of the Sun. ... The spot moved across the Earth at nearly 2,000 kilometers per hour, giving many viewers less than two hours to see a partially eclipsed Sun . ... About APOD | ...

Besides the Moon, Earth now has many artificial satellites, put up by us earthlings for a variety of purposes. ... In principle, a satellite could then orbit just above its surface. ... Dividing both sides by m shows that the mass of the satellite does not matter, and leaves . ... Any slower and it loses altitude and hits the Earth ("2"), any faster and it rises to greater distance ("3"). ... This is Kepler's 3rd law , for the special case of circular orbits around Earth. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Armagh Planetarium . ... Alien Life . ... Space Flight . Human Exploration . ... Earth Satellites . ... Science Fiction . ... 4 Comments There are cosmic threats to life on Earth.Hiding in the depths of space are things lethal beyond imagining.One day the End will be nigh for real.A forthcoming conference, part of [ ] . ... Here you will find the latest news and views from the fascinating worlds of astronomy and space exploration. ...

... 22.Reference Frames . ... Inertial Forces . 23a. The Centrifugal Force . ... When calculating the motions of the oceans and the atmosphere, it is much easier to use reference points on the rotating Earth and add a centrifugal force to all equations. ... The rest arises because the Earth is not a perfect sphere: the centrifugal force of its rotation causes its equator to bulge out , making the surface there more distant from the Earth s center and thus weakening the gravitational pull. ...

... Bad Astronomy . ... Every few months, one of a series of questions comes up on the USENET group sci.astro involving tides, or the rotation of the Moon, or the recession of the Moon from the Earth. ... Why the Moon's rotation period is the same as the length of time it takes to orbit the Earth (same as number 1, but phrased differently). ... But when this happens, the time it takes for the Earth to rotate once will be slowed to exactly the same time it takes for the Moon to go around the Earth once! ...

... Tonight's Sky . ... The Magazine . ... Star Atlas . ... An artificial comet holds secrets to Earths life . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... The planet has extreme temperature swings and perhaps active lava flows. ... A digital supplement to Astronomy magazine. ... Join TravelQuest International with Astronomy and Discover magazines on one of three great tour options surrounding this celestial spectacle . ... Astronomy Magazine . ...

The Earth. ... The middle raiding of the Earth is 6371,032 km, the pole 6356,777 km equatorial - 6378,160 km. The Earth surface area is 510,2 mln km^2, 70,8% of which is the World ocean. ... According to the modern cosmogonical views the Earth was formed 4,6 - 4,7 billions years ago from the protoplanet cloud captured by the Sun. ... The Earth is conditionally divided into 3 parts: a bark a cloak and a core (in the centre). The external layer - the bark is 35 km thick. ... Above the Earth. ...

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... Click on this icon if you would like to see a collection of snapshots of actual pages from the "Other Worlds from Earth" Electronic PictureBook. ... The Other Worlds from Earth Electronic PictureBook is a HyperCardЁ stack designed to run on a color MacintoshЁ computer with at least 2.5 megabytes of available RAM, sufficient hard disk space to contain the Electronic Picturebook, System 7.0, and HyperCard 2.1 or HyperCard Player 2.1. ...

Mars has long captured our imaginations and remains a serious target for human exploration. With evidence of water once being plentiful on this planet, we take the maximum precautions when exploring this world. ... Europa is a moon of Jupiter. ... Water and heat make it another candidate for a possible abode of life. ... Eros, was the first asteroid to have a spacecraft put in orbit around it. Given its size and location, it is not a likely candidate to have life on it. ...

Back To The Astronomy Cafe" Book Review . Articles | ... Astronomy Net . ... A review of "Back to the Astronomy Cafe" . ... Pretty much near the Genesis of the modern Internet, Sten Odenwald has set out to help folks with questions about Astronomy by actually answering them. This book is the next in a series of common questions he has taken the time to answer in years past. ... www.astronomy.net . About Astronomy Net | ... dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

Jupiter is the largest of the nine planets, more than 10 times the diameter of Earth and more than 300 times its mass. ... The mean density of Earth is 5.245 times that of water. The pull of gravity on Jupiter at the top of the clouds at the equator is 2.4 times as great as gravity's pull at the surface of Earth at the equator. ... It is tipped about 11њ to Jupiter's axis of rotation, similar to Earth's, but it is also offset from the center of Jupiter by about 10,000 kilometers (6,200 miles). ...

... 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. ...

... Gravity is responsible for keeping your feet on the ground and keeping the Earth and all other planets in our Solar System in their orbits around the Sun. ... Einstein's theory of gravity, known as the theory of General Relativity. This suggested that gravity is actually the curving of the fabric of the Universe, known as 'spacetime', around objects. For instance, a very heavy star warps the space around it, causing a deep well in the fabric, and pulling in anything that comes too close. ...

... The first powerful active areas of the new solar cycle have now come into view from Earth ( video, 4.0 MB ). ... Back on 7 May, two space observatories, STEREO (USA) and TESIS/Coronas-Photon (Russia), simultaneously registered a sharp rise in activity on the eastern edge of the solar disk. ... At the present time, TESIS telescopes are tracking these active areas. ... The TESIS observatory ї TESIS: www.tesis.lebedev.ru . ... The First Powerful Areas of the New Solar Cycle (WMV movie, 4.0 MB) . ...

... The greenhouse effect . ... The Earth receives short-wave radiation from the sun, one-third of which is reflected back out to space. The remaining radiation is absorbed by the surface and heats up the planet. Then the Earth emits infra-red radiation because of the greenhouse gases contained in the atmosphere. ... Problems arise when greenhouse gases such as carbon dioxide and methane increase due to human activities and the Earth gets hotter. ...

... Peter J.K. "Jeff" Wisoff (Ph.D) . NASA Astronaut (former) . ... A veteran of four space flights, STS-57 in 1993, STS-68 in 1994, STS-81 in 1997 and STS-92 in 2000, Dr. Wisoff has logged a total of 42 days, 56 hours, 1 minute and 48 seconds in space, including , 19 hours and 53 minutes of EVA time in three space walks. ... Following 183 orbits of the Earth in 269 hours and 46 minutes, the eleven-day mission ended with Space Shuttle Endeavour landing at Edwards Air Force Base, California. ...