... 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 . ...

... Listed below are questions submitted by users of "The Great Magnet, the Earth" and the answers given to them. ... In "The Exploration of the Earth's magnetosphere" on the magnetic environment of the Earth in space (a few Q duplicated here) . ... 11) Magnetic Shielding . ... 51) Can electricity be generated from the Earth's magnetic field? ... 9) Measuring Earth's magnetic field . ... 6) Reversals of the Earth's field (4 queries) . ... 42) Could generated electricity affect Earth's magnetic field? ...

... Listed below are questions submitted by users of "The Great Magnet, the Earth" and the answers given to them. ... In "The Exploration of the Earth's magnetosphere" on the magnetic environment of the Earth in space (a few Q duplicated here) . ... 11) Magnetic Shielding . ... 51) Can electricity be generated from the Earth's magnetic field? ... 9) Measuring Earth's magnetic field . ... 6) Reversals of the Earth's field (4 queries) . ... 42) Could generated electricity affect Earth's magnetic field? ...

... Two years ago, the Clementine space probe snatched this picture of the Moon as lit not by direct sunlight, but by reflected sunlight from Earth. ... Out With the Tide . ... Tides occur because the gravitational force between two bodies decreases with distance. ... The imbalanced gravitational pull of the Moon causes the oceans to be slightly non-spherical, creating two high tides and two low tides. ... In return, the Moon exerts a gravitational force on the high tide, causing Earth to rotate slower....

... This appartus will drop a mass from different heights. When the mass strikes the ground, some percentage of its original energy will be absorbed by the ground. ... The percentage of the energy which is absorbed by the surface on each "bounce" (EAS) . ... The impact velocity of the object will also be given at each bounce. ... Start= Drop the ball after Energy, Mass and EAS have been set; resume after step or pause has been selected . ... Reset = Reset experiment to intial values . ...

... 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! ...

... 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. ...

... Bringing news from across the Universe to children all around the world . ... In answer to that, one of the main ingredients of the Universe is dark matter, perhaps one of the biggest mysteries of all. Dark matter is a mysterious and peculiar material that got its name because doesn?t give off any light - it?s totally invisible. ... In fact, almost every galaxy with the same shape as the Milky Way (which has a spiral shape) is surrounded by an envelope of dark matter. ... Cool Fact . ...

... How much brighter is the Sun as viewed from the planet Mercury as compared to Earth ? ... Actually, all of these questions can be answered through a very simple mathematical relationship known as the inverse square law. ... As the distance from the Sun increases the surface area of the sphere grows by the square of the distance. ... Common sense tells us that the Sun will be brighter and the inverse square law tells us how much brighter. ... gr = 0.912 G or 91.2% gravity felt at Earth's surface. ...

Russian SHAREABLE DATA CENTER Institute of Solar-Terrestial Physics SB RAS . ... Here we present the ionospheric parameters variations for quiet conditions. ...

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. ...

God Science Forum Message . ... God and Science ћ SETI ћ Software ћ UFO ћ XEphem . ... God and Science | ... God Darwin Can Co-exist . ... One Earth day is the time it takes the planet to revolve one complete time around its axis. ... The bible says in the beginning there was darkness and god created light. ... www.astronomy.net . About Astronomy Net | ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... Planets . ... Earth Satellites . ... The newly discovered ?mega-Earth? ... Its sibling, the lava world Kepler-10b, is in the background (the two planets? proximity is grossly exaggerated) .€а Kepler-10c has a diameter of about 29 000 km, 2.3 times as large as Earth, and weighs 17 times as much. ... The first mega-earth to be discovered is Kepler-10c which orbits a star lying about 560 light years from the Sun in the constellation Draco. ... Astronomers Find a New Type of Planet: The ?Mega-Earth? ...

... Editor's choices for the most educational Astronomy Pictures of the Day about Earth: . APOD: 2005 January 2 - Welcome to Planet Earth . Explanation: Earth , the third planet from a star named the Sun . ... Over 70 percent of the Earth's surface is water . ... Earth is the only planet in the Solar System where the present surface temperature and pressure allow the three forms of water, solid (ice) , liquid (ocean) , and gas ( water vapor condensing in clouds ) to exist simultaneously . ...

otherwise stated, constants are denoted by the following symbols and may be taken to have the values below Elementary charge Speed of light in vacuum Planck constant Permeability of vacuum Permittivity of vacuum Unified atomic mass constant Rest mass of proton Rest mass of electron Boltzmann constant Avogadro constant Gravitational ... A pulse of light of frequency f is emitted from the space station towards the ship at exactly the time the ship passes the Earth in the Earth frame. ...

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. ...

... The QBO period is equal to a linear combination of the frequencies corresponding to the doubled periods: of the tidal year (0.97 year ), of the regression of nodes (18.6 years ), and of the motion of perigee ( 8.85 years ) of the Earth's monthly orbit : 1 2 1 1 1 0.97 18.61 8.85 1 2.3 yr (1) In other words, the quasi-biennial oscillation of the wind direction in the equatorial stratosphere is a combined oscillation ...

... Moon Phase below . ... ARTICLE: Why the moon always shows us the same face . ... Before you continue reading, you should know that this was not always the case, i.e. the Moon once was rotating with respect to the Earth, so that on every night a terrestrial observer (if there was one, because this was long, long before mankind appeared on our planet, and even before any major animals had appeared) saw another face of the Moon. ... Figure 1 (not to scale) shows how we can imagine the system Earth-Moon...

Trudy GAISH, vol. LXV, 1996 . Abstracts . The global distribution of average (5 O x 5 O ) depths . of Mohorovicic discontinuity on the Earth . ... Such analysis allows detecting whether the sources of the largest anomalies reside within the Earth's core. This is possible if the limit depths of the sources exceed the depths of the core-mantle boundary. ... by Pasinok S.L. Influence of the Earth’s cover on the polar free oscillation of the Earth’s inner core is considered. ...

... As you may know, I'm writing a book for Prentice-Hall, due in January, called Peer Instruction for Astronomy. ... I'm looking for a colleague or two willing to review/critique some of the ConcepTest questions that will be included in the book. See http://hea-www.harvard.edu/~pgreen/educ/ConcepTests.html I suspect that a significant contribution would only take you 2-3 hours. ... ConcepTests are multiple choice questions which the students pose to each other in small groups, during class. ...