... 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 . ... 15.08.2003 . ... Credit: Malin Space Science Systems , MGS , JPL , NASA Explanation: High-resolution imaging of an area in the Schiaparelli Basin of Mars on June 3 by the MGS Mars Orbiter camera produced this stunning example of layered formations within an old impact crater. ... August . ... August 2003 . ... Publications with keywords: Mars - crater - sedimentary rock . Publications with words: Mars - crater - sedimentary rock . ... Victoria Crater on Mars . ...

... 2003 August 15 . Sedimentary Mars . Credit: Malin Space Science Systems , MGS , JPL , NASA . Explanation: High-resolution imaging of an area in the Schiaparelli Basin of Mars on June 3 by the MGS Mars Orbiter camera produced this stunning example of layered formations within an old impact crater. ... The crater could well have been filled with water in Mars' distant past, perhaps resting at the bottom of a lake filling the Schiaparelli impact basin. ... About APOD | ...

Educator's Guide to Impact Craters . ... Just about all craters have deep central depressions, raised rims, and a blanket of ejected material surrounding them. ... Look for classical cratering features: basin, raised rim, ejecta blanket (material excavated from the crater and dumped around it, visible as white flour on the colored powder), and rays (material shot out at high velocity forming lines pointing directly away from the impact site). ... The material lies like a blanket around the crater. ...

... Carefully measure the diameter of the craters formed by the impact without disturbing the sand. ... Crater diameter increases with increasing mass. ... Without disturbing the sand, carefully measure the crater diameter. ... Did you measure any difference in the diameters of the craters? Yes, as velocity increases, so does crater diameter. ... Impact cratering. ... Impact craters can be demonstrated with younger or less advanced students using mud instead of sand and ball bearings. ...

Opportunity snapped this false-color picture November 22, 2006, which shows layered details in the rock promontory called Cape Verde. This view combines several exposures taken by the rover's panoramic camera. The upper portion of the crater wall contains a jumble of material tossed outward by the impact that excavated Victoria Crater. ... Below the jumbled material in the upper part of the wall are layers that survive relatively intact from before the crater-creating impact. ...

... Sternberg State Astronomical Institute, 119899, Moscow, Russia . ... 50_Kozlova_Shevchenko.pdf - 212KB . A.A. Berezhnoy (1), O.R. Baransky (2), K.I. Churyumov (2), V.V. Kleshchenok (2), E.A. Kozlova (1), V. Mangano (3), V.O. Ponomarenko (2), Yu.V. Pakhomov (4), V.V. Shevchenko (1), yu. ... Berezhnoy A.A., Kozlova E.A., Shevchenko V.V. в сборнике 36th Annual Lunar and Planetary Science Conference, серия Lunar and Planetary Institute Science Conference Abstracts, том 36, с. 1061 тезисы . ...

A team of scientists believes they have discovered a chain of impact craters in the central African country of Chad that suggests ancient Earth may have been hit by a large, fragmented comet or asteroid similar to the Shoemaker-Levy 9 comet that slammed into Jupiter in 1994. The craters were discovered in radar images of the Earth taken by the Spaceborne Imaging Radar C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) that flew on the Space Shuttle Endeavour in April and October of 1994. ...

... Bad Astronomy . ... Bitesize Astronomy . ... Bad Astro Store . ... Site Info . ... It is from from Voyager 1 and shows a whopping big impact crater dominating the profile of the moon. Note that Mimas is about 400 kilometers across (about 250 miles). ... The wall around the crater is 5 kilometers high, and that central peak rises 6 kilometers above the surface (many impact craters have a large central peak which is caused by a pressure rebound from the impact). ... 2008 Phil Plait. ...

The rates of build-up in the atmosphere of human-made compounds that deplete the ozone layer (e.g., chlorofluorocarbons (CFCs) and halons) have slowed in recent years as a direct result of reductions in global emissions of these compounds. ... The peak global ozone depletions are expected to occur during the next several years. ... Methyl bromide continues to be viewed as a significant ozone- depleting chemical. ...

... View from a killer asteroid (W. Hartmann) . Asteroid Ida . ... Asteroids are made of rock and/or iron - much higher strength material, so a larger fraction survives to impact. ... Meteor Crater, Arizona: 1200 m x 70 m : 20 Megatons, D~10 metres? ... We may even have found a piece of the killer asteroid. expected frequency - once per 100 million years . ... Nearer to home, Clearwater Lakes, in Quebec, form a pair of impact craters, 32 km and 22 km in diameter respectively, aged ~290 million years . ...

... About meteorites . ... Meteoritic data . Impact Crater Smerdyachee . ... Based on Smerdyachee's depth, near circularity, and its mounded wall, and analysis by N.A. Fillin of nearby Roshal, Russia, the Estonian scientists Yu.V. Krestlane and K.H. Mella proposed in 1987 that Smerdyachee Lake is a meteorite crater. ... In 2002, the Laboratory of Meteoritics of the Vernadsky Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences explored this mysterious lake. ...

The AstroGuide . ... AstroGuide | ... AstroGuide Listing . ... See many more Astronomy Listings by: Category or Alphabet . Information on impact craters here on Earth. ... Listed Since July 15, 1998 . ... Web Site . ... Additional Information . Web . www.astronomy.net . About Astronomy Net | ... Unless otherwise specified, web site content Copyright 1994-2016 John Huggins All Rights Reserved . dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . are trademarks of John Huggins ...

... Gallery . ... Comet Shoemaker-Levy 9 Impact Images . Sidebar Left . Sidebar Top . ... Title: Comet Shoemaker-Levy 9 Impact Images . Description: Comet Shoemaker-Levy 9 meets Jupiter - July 1994 . ... Owner: Gallery Administrator . ... 3.09, 3.28, 3.42 micron image after fragmentтАж . Views: 2399 . By: Gallery Administrator . 2.34 micron images imact sequence for fragmenтАж . ... 2.34 micron image of fragment D impact . ... Composite 3.42, 3.59, 3.99 micron image of poтАж . ...

Astronotes Armagh Planetarium's Stellar Blog! ... Question:What do you need to protect an expensive state-of-the-art robotic vehicle that is far from human reach and about to crash at high speed on a rocky alien surface?Answer:Retrograde rockets, parachutes, airbags, and an aeroshell.These are found in the makeup of a lander module that was used to bring rovers Spirit and Opportunity described by the missionтАЩs director as тАЬrobotic field geologistsтАЭ safely to the Martian surface in 2004. ...

... R2241 Date Received: 2006-Jun-01 10:36:19 Technical Page Proposal Type: General Category: Sub-Category: Observation Category: Total Time Requested: Minimum Useful Time: Prop osal Title: ABSTRACT: Regular Planetary Radar Radar Solar System 12 Hours High-Resolution Radar Studies of the Moon's Mega-Regolith The Moon's surface is exposed to constant bombardment by meteorites, and over time these impacts create a mixed layer of pulverized dust and rock fragments called the regolith. ...

... Future seminars . P a s t seminars . ... Deep Impact: Excaving Comet Tempel 1 " . ... On 4 July 2005 Deep Impact collided with comet Tempel 1, excaving a crater. Deep Impact consisted of two fully functional spacecraft: an impacting spacecraft weighting 364 kg and a flyby spacecraft for observing the impact and relaying data from the impactor. ... The impact was also observed by over 80 ground-based observatories and by several spacecraft (Rosetta, Hubble Space Telescope, Chandra, Spitzer). ...

... The ejecta cone will detach. ... Mission Trajectory Launch Ja n 2, 200 4 Earth Flyby D ec 31, 2004 SUN S/C S/C Ea r th Orbit · · · Tempel 1 Orbit (5.5 year Period) Impact July 4, 2005 dsun = 1.51 AU dearth = 0.895 AU Earth at Encounter Perihelion July 5, 2005 dsun = 1.51 AU dearth = 0.900 AU Approach: E-2 mo to E-24 hr (E = impact event) · Images and spectra of coma to study rotation Impactor release: E-24 hr to E · Color images of coma and nucleus · Spectra of coma and nucleus ...

... the radiative transfer equation (RTE) for the randomly-irregular magnetized plasma has been derived on the base of general grounds of the multiple scattering theory . ... Solutions of several absolute tasks of the scattering theory have been obtained (on the optical depth of the ionospheric plasma layer, on the value of radio wave anomalous attenuation, on anomalous refraction, on the backscattered signal intensity for the source being placed within a plasma layer). ...

XMM­Newton CCF Release Note XMM­CCF­REL­71 RGS2 CCD2 Thickness of SiO 2 Layer C. Erd April 11, 2001 1 CCF components Name of CCF VALDATE List of Blocks changed CAL VERSION XSCS flag RGS2 QUANTUMEF 0007 1998­01­01T00:00:00 CCD DESC --- NO 2 Changes For CCD2 the thickness of the in­active layer of SiO 2 is increased from = 0 to 40 nm. ... The accuracy with this CCF is estimated to ё 5%. 1 XMM­Newton CCF Release XMM­CCF­REL­71 Page: 2 References [1] C. de Vries. Comparing RGS1/RGS2 and CCD2 RGS2. ...