Exploze Na Měsíci

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Č Měsíc byl zasažen také. Ale na rozdíl od Zem ě, M ěsíc nemá žádnou atmosféru, Zákrytová a astrometrická sekce AS která by meteoroidy zbrzdila a zm ěnila je v neškodné padající hv ězdy. Na M ěsíci, meteoroidy ude ří do povrchu a dojde k explozi. "Záblesk, který jsme vid ěli, " říká Suggs, "m ěl jasnost p řibližn ě 7. hv ězdné velikosti." To je dva a p ůlkrát mén ě, než je jas nejslabší hv ězdy, kterou člov ěk může vid ět neozbrojenýma o čima, ale pro skupinu 25 cm dalekohled ů je to pom ěrn ě snadný cíl. Cooke odhaduje, že spat řený dopad by mohl odpovídat kráteru o pr ůměru kolem 3 metr ů a hloubce p řibližn ě 0.4 metru. K hledání takového kráteru jsou jeho rozm ěry p říliš malé. Dokonce ani HST by jej nebyl schopen odhalit. Je nutné si únor 2006 (2) uv ědomit, že M ěsíc je ve vzdálenosti 384,400 km a v té i kosmický teleskop nerozliší podrobnosti menší než 60 metr ů. Zajímavosti: Popsaný p řípad není prvním, kdy byl na povrchu M ěsíce zaznamenán dopad meteoroidu. B ěhem meteorických bou ří roje Leonid v letech 1999 a 2001 astronomové amaté ři i profesionálové zaznamenali p řinejmenším p ůl tuctu ě podobných záblesk ů v rozp ětí jasností od 7. až do 3. mag. Potvrzením reálnosti Exploze na M síci těchto úkaz ů je skute čnost, že byly sou časn ě zachyceny dostate čně vzdálenými pozorovateli. Také jste si mysleli, že na M ěsíci se nic zajímavého nem ůže stát? 23. Prosince 2005: V ědci z NASA sledovali explozi na Měsíci. Výbuch, který svou intenzitou odpovídal p řibližn ě Záblesk vyvolaný dopadem m ěsí ční Tauridy rozložený do šesti časov ě na sebe energii uvoln ěné explozí 70 kg navazujících snímk ů. TNT, se odehrál blízko okraje ě ř ťů Od maxima roje Leonid v roce 2001, astronomové nev nují této problematice Mare Imbrium (Mo e deš ) příliš mnoho času. "Záblesky na M ěsíci vyšly z módy, " říká Suggs. Ale NASA 7. listopadu 2005, když se plánuje návrat astronaut ů na M ěsíc v roce 2018 a je čas za čít op ět se s povrchem našeho souputníka systematickým sledováním t ěchto úkaz ů. srazil rychlostí 27 km/s ř č ě č ů ě Stojí p ed námi mnoho otázek, které ekají na svoji odpov d: "Jak asto meteoroid o pr m ru kolem dochází k mohutným srážkám M ěsíce s velkými meteoroidy? Jedná se jen o 12 cm. ů ťů č č č pr vodní jev silných meteorických deš jako jsou Leonidy i Tauridy? Nebo Te ka ozna uje místo dopadu meteoroidu ze 7. 11. 2005. můžeme o čekávat srážky se sporadickými meteory?'" vyslovil jen n ěkteré Suggs. "Jaké bylo naše p řekvapení," říká výzkumný pracovník Marshall Space Flight Ale odpov ědi se musíme dozv ědět v čas. Center (MSFC) Rob Suggs, který byl jedním z dvojice, která záblesk zaznamenala. "Pravd ěpodobnost, že by byl astronaut p římo zasažen velkým meteoroidem, je On a jeho kolega Wes Swift práv ě testovali nový dalekohled a videokameru, naprosto zanedbatelná, " říká Cooke. Ale na druhé stran ě uznává, že skute čnou kterou sestavili práv ě pro sledování záblesk ů zp ůsobovaných dopady meteoroid ů pravd ěpodobnost nejsme schopni ur čit, "protože nemáme k dispozici dostatek na M ěsíc. Hned v první zkušební noci, „jsme jeden takový záblesk zachytili," říká pozorovacích podklad ů, abychom ji byli schopni spo čítat." Navíc, i když Suggs. připustíme, že pravd ěpodobnost p římého zásahu astronauta se blíží nule, ur čité „Objekt, který ude řil do M ěsíce, byla pravd ěpodobn ě Taurida," říká nebezpe čí m ůže p ředstavovat takováto hrozba pro celou m ěsí ční základnu. meteorický expert MSFC Bill Cooke. Jinými slovy, byla to část stejného „Ješt ě v ětší obavy než samotná srážka m ůže vyvolávat rozst řik sekundárních meteorického dešt ě, který zasypal zemi ohnivými záblesky meteor ů v pozdním meteoroid ů vyvolaný pimárním výbuchem“, upozor ňuje Suggs. Nikdo dnes neví, říjnu a za čátkem listopadu 2005. jak daleko taková sprška m ůže dolet ět a nakolik nebezpe čná m ůže být. Ot řes m ěsí ční p ůdy v oblasti srážky by trosek, který by se nalézal v pravý čas a na pravém míst ě tak, aby mohl zp ůsobit mohl také zví řit všudyp řítomný prach a to pozorovaný záblesk." možná v překvapiv ě rozsáhlé oblasti. Nemohlo to být ani kosmické zá ření. "Zachytili jsme m ěsí ční explozi na p ěti po Měsí ční prach je elektrostaticky nabitý a sob ě následujících snímcích ( čož odpovídá časovému rozp ětí 150 msec). neoby čejn ě p řilnavý. Proto i jeho Kosmický paprsek by m ěl zp ůsobit záblesk pouze na jediném záb ěru," vysv ětluje sebemenší množství m ůže zp ůsobit velké Suggs. nep říjemnosti: m ůže se dostat do „kloub ů“ A kone čně, nemohl to tém ěř jist ě být ani meteor v zemské atmosfé ře. "Aby se skafandru, m ůže ulp ět na pr ůzoru měsí ční dopad mohl vydávat za meteor v zemské atmosfé ře, muselo by se jednat o skafandru a dokonce m ůže i zne čistit případ tzv. stacionárního meteoru. Tedy takového, který by m ěl sm ěr p řesn ě na vzduch pro astronauty, kdyby se dostal po Marshall Space Flight Center, aby vypadal jako bod a ne pruh sv ětla, " říká Suggs. příchodu z procházky po povrchu do "Meteoroid dopadající na M ěsíc je ale jako vysv ětlení sledovaného úkazu obytných prostor astronaut ů. Není pravd ěpodobn ější. Navíc sv ětelná k řivka našeho impaktu má stejný tvar jako vylou čeno, že dopady meteoroid ů jsou sv ětelné k řivky p ředchozích lunárních Leonid z let 1999 a 2001 a sou časn ě zdrojem lunárních „prašných bou ří. Takové otázky stojí p řed námi! neodpovídá starším sv ětelným k řivkám stacionárních meteor ů.“ Suggs a jeho tým proto plánují ud ělat více pozorování. "P řemýšlíme o dlouhodobém programu ne pouze b ěhem vysoké aktivity hlavních meteorických roj ů, ale také v čase mezi nimi. Sou časn ě pot řebujeme vyvinout software, který odhalí záblesky na získaných záznamech automaticky. Zírat čty ři by ješt ě více Transneptun z blízka, hodin na záznamy a hledat záblesky trvající zlomky sekund m ůže za čít nudit; toto je práce pro po číta č." ale až za více než S takovýmto zlepšením techniky a rozší řením pozorovacího času, je systém dev ět let připraven zachytit mnohem více m ěsí čních meteor ů než se to da řilo dosud. Suggs k tomu dodává, "Jsem p řipraven na mnoho p řekvapení." K nejvzdálen ější (stále ješt ě) Více informací planet ě slune ční soustavy – Plutu – Pokud je dnes známo, Suggs a Swift byli jediní, kdo zaznamenali dopad ze 7. se vydala americká meziplanetární listopadu 2005. „Ale to je dáno tím, že jsme byli jediní, kdo se dívali," říká Suggs. sonda New Horizons. Po dvou Tak se stalo, že na rozdíl od lunárních Leonid z let 1999 a 2001, nebyla srážka odkladech startu zahájila svoji s Tauridou z roku 2005 potvrzena žádným dalším pozorovatelem. dlouhou cestu 19. ledna 2006 ve čer ř č ě ě ř P esto, "jsme si na 99% jisti, že to byl skute n úkaz na M síci," íká Suggs. našeho času. Ale jsou i jiné možnosti vysv ětlení, nap ř. • satelit procházející p řed M ěsícem a pableskující v slune čním sv ětle; Sonda velice rychle protnula dráhu M ěsíce (p řibližn ě 9 hodin po startu) a • kosmický paprsek kosmického vydala se do meziplanetárního prostoru. Již v dubnu letošního roku se dostane do zá ření, který práv ě narazil do vzdálenosti Marsu a v únoru 2007 prolétne kolem Jupitera. Práv ě nejv ětší planeta ji CCD čipu videokamery; svou gravitací dodá ješt ě v ětší rychlost a navede ji na optimální trajektorii k Plutu. • meteor v zemské atmosfé ře, Jupiter také poslouží ke kalibraci v ědeckých p řístroj ů. přímo mezi Zemí (pozorovacím New Horizons se nedostane na ob ěžnou dráhu kolem cílového objektu, ale stanovišt ěm) a M ěsícem. pouze kolem Pluta proletí. Výzkum soustavy Pluto – Charón (a jejího okolí, kde "Nev ěř íme, že to byl satelit, " nyní víme o dvou dalších objektech) bude zahájen 14. 2. 2015. Do nejt ěsn ější říká Cooke poté, co spolu s leteckou blízkosti se sonda dostane 14. července 2015 (cca 10000 km od Pluta a 27000 km inženýrkou Heather McNamarovou, od m ěsíce Charón). Ukon čení této fáze práce sondy je plánováno na 11. 8. 2015. prohledal NORAD ův katalog Ani to však nebude konec projektu. V letech 2016 až 2020 se bude New obsahující 8363 objekt ů Horizons v ěnovat výzkumu vybraných t ěles Kuiperova pásu, o nichž nám, jak pohybujících se po zemské orbit ě. doufají v ědci, podá naprosto nové a unikátní informace. "Nebyl tam žádný satelit nebo kus č. těleso průměr chyba č. těleso průměr chyba č km +/-km km +/-km Slune ní soustava podle velikosti 235 388 Charybdis 119 278 233 Asterope 108 236 909 Ulla 119 279 240 Vanadis 108 leden 2005 (2) 237 1093 Freda 119 280 Portia U12 106 238 596 Scheila 118 281 42 Isis 106 Pokra čování z čísla 1/2006 239 34 Circe 118 282 175 Andromache 106 240 481 Emita 116 283 181 Eucharis 106 č. těleso průměr chyba č. těleso průměr chyba 241 683 Lanzia 116 284 393 Lampetia 106 km +/-km km +/-km 242 56 Melete 116 285 570 Kythera 106 145 49 Pales 153 190 200 Dynamene 132 243 814 Taurus 116 286 748 Simesia 106 146 51 Nemausa 153 191 92 Undina 132 244 57 Mnemosyne 116 287 791 Ani 106 147 1172 Aneas 151 192 419 Aurelia 132 245 505 Cava 114 288 192 Nausikaa 106 148 20 Massalia 150 193 654 Zelinda 132 246 230 Athamantis 114 289 162 Laurentia 105 149 283 Emma 150 194 712 Boliviana 132 247 659 Nestor 114 290 191 Kolga 105 150 137 Meliboea 150 195 159 Aemilia 130 248 91 Aegina 114 291 2223 Sarpedon 105 151 1998 WW31B 150 196 602 Mariana 130 249 545 Messalina 114 292 3451 Mentor 105 152 361 Bononia 148 197 46 Hestia 130 250 140 Siwa 114 293 30 Urania 103 153 308 Polyxo 148 198 27 Euterpe 130 251 751 Faina 114 294 114 Kassandra 103 154 18 Melpomene 148 199 1867 Deiphobus 130 252 275 Sapienta 114 295 148 Gallia 103 155 209 Dido 148 200 405 Thia 129 253 595 Polyxene 114 296 303 Josephina 103 156 211 Isolda 148 201 276 Adelheid
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  • Mineralogies and Source Regions of Near-Earth Asteroids ⇑ Tasha L

    Mineralogies and Source Regions of Near-Earth Asteroids ⇑ Tasha L

    Icarus 222 (2013) 273–282 Contents lists available at SciVerse ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Mineralogies and source regions of near-Earth asteroids ⇑ Tasha L. Dunn a, , Thomas H. Burbine b, William F. Bottke Jr. c, John P. Clark a a Department of Geography-Geology, Illinois State University, Normal, IL 61790, United States b Department of Astronomy, Mount Holyoke College, South Hadley, MA 01075, United States c Southwest Research Institute, Boulder, CO 80302, United States article info abstract Article history: Near-Earth Asteroids (NEAs) offer insight into a size range of objects that are not easily observed in the Received 8 October 2012 main asteroid belt. Previous studies on the diversity of the NEA population have relied primarily on mod- Revised 8 November 2012 eling and statistical analysis to determine asteroid compositions. Olivine and pyroxene, the dominant Accepted 8 November 2012 minerals in most asteroids, have characteristic absorption features in the visible and near-infrared Available online 21 November 2012 (VISNIR) wavelengths that can be used to determine their compositions and abundances. However, formulas previously used for deriving compositions do not work very well for ordinary chondrite Keywords: assemblages. Because two-thirds of NEAs have ordinary chondrite-like spectral parameters, it is essential Asteroids, Composition to determine accurate mineralogies. Here we determine the band area ratios and Band I centers of 72 Meteorites Spectroscopy NEAs with visible and near-infrared spectra and use new calibrations to derive the mineralogies 47 of these NEAs with ordinary chondrite-like spectral parameters. Our results indicate that the majority of NEAs have LL-chondrite mineralogies.
  • The Minor Planet Bulletin

    The Minor Planet Bulletin

    THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 38, NUMBER 2, A.D. 2011 APRIL-JUNE 71. LIGHTCURVES OF 10452 ZUEV, (14657) 1998 YU27, AND (15700) 1987 QD Gary A. Vander Haagen Stonegate Observatory, 825 Stonegate Road Ann Arbor, MI 48103 [email protected] (Received: 28 October) Lightcurve observations and analysis revealed the following periods and amplitudes for three asteroids: 10452 Zuev, 9.724 ± 0.002 h, 0.38 ± 0.03 mag; (14657) 1998 YU27, 15.43 ± 0.03 h, 0.21 ± 0.05 mag; and (15700) 1987 QD, 9.71 ± 0.02 h, 0.16 ± 0.05 mag. Photometric data of three asteroids were collected using a 0.43- meter PlaneWave f/6.8 corrected Dall-Kirkham astrograph, a SBIG ST-10XME camera, and V-filter at Stonegate Observatory. The camera was binned 2x2 with a resulting image scale of 0.95 arc- seconds per pixel. Image exposures were 120 seconds at –15C. Candidates for analysis were selected using the MPO2011 Asteroid Viewing Guide and all photometric data were obtained and analyzed using MPO Canopus (Bdw Publishing, 2010). Published asteroid lightcurve data were reviewed in the Asteroid Lightcurve Database (LCDB; Warner et al., 2009). The magnitudes in the plots (Y-axis) are not sky (catalog) values but differentials from the average sky magnitude of the set of comparisons. The value in the Y-axis label, “alpha”, is the solar phase angle at the time of the first set of observations. All data were corrected to this phase angle using G = 0.15, unless otherwise stated.
  • (2000) Forging Asteroid-Meteorite Relationships Through Reflectance

    (2000) Forging Asteroid-Meteorite Relationships Through Reflectance

    Forging Asteroid-Meteorite Relationships through Reflectance Spectroscopy by Thomas H. Burbine Jr. B.S. Physics Rensselaer Polytechnic Institute, 1988 M.S. Geology and Planetary Science University of Pittsburgh, 1991 SUBMITTED TO THE DEPARTMENT OF EARTH, ATMOSPHERIC, AND PLANETARY SCIENCES IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN PLANETARY SCIENCES AT THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY FEBRUARY 2000 © 2000 Massachusetts Institute of Technology. All rights reserved. Signature of Author: Department of Earth, Atmospheric, and Planetary Sciences December 30, 1999 Certified by: Richard P. Binzel Professor of Earth, Atmospheric, and Planetary Sciences Thesis Supervisor Accepted by: Ronald G. Prinn MASSACHUSES INSTMUTE Professor of Earth, Atmospheric, and Planetary Sciences Department Head JA N 0 1 2000 ARCHIVES LIBRARIES I 3 Forging Asteroid-Meteorite Relationships through Reflectance Spectroscopy by Thomas H. Burbine Jr. Submitted to the Department of Earth, Atmospheric, and Planetary Sciences on December 30, 1999 in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Planetary Sciences ABSTRACT Near-infrared spectra (-0.90 to ~1.65 microns) were obtained for 196 main-belt and near-Earth asteroids to determine plausible meteorite parent bodies. These spectra, when coupled with previously obtained visible data, allow for a better determination of asteroid mineralogies. Over half of the observed objects have estimated diameters less than 20 k-m. Many important results were obtained concerning the compositional structure of the asteroid belt. A number of small objects near asteroid 4 Vesta were found to have near-infrared spectra similar to the eucrite and howardite meteorites, which are believed to be derived from Vesta.
  • The Minor Planet Bulletin, It Is a Pleasure to Announce the Appointment of Brian D

    The Minor Planet Bulletin, It Is a Pleasure to Announce the Appointment of Brian D

    THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 33, NUMBER 1, A.D. 2006 JANUARY-MARCH 1. LIGHTCURVE AND ROTATION PERIOD Observatory (Observatory code 926) near Nogales, Arizona. The DETERMINATION FOR MINOR PLANET 4006 SANDLER observatory is located at an altitude of 1312 meters and features a 0.81 m F7 Ritchey-Chrétien telescope and a SITe 1024 x 1024 x Matthew T. Vonk 24 micron CCD. Observations were conducted on (UT dates) Daniel J. Kopchinski January 29, February 7, 8, 2005. A total of 37 unfiltered images Amanda R. Pittman with exposure times of 120 seconds were analyzed using Canopus. Stephen Taubel The lightcurve, shown in the figure below, indicates a period of Department of Physics 3.40 ± 0.01 hours and an amplitude of 0.16 magnitude. University of Wisconsin – River Falls 410 South Third Street Acknowledgements River Falls, WI 54022 [email protected] Thanks to Michael Schwartz and Paulo Halvorcem for their great work at Tenagra Observatory. (Received: 25 July) References Minor planet 4006 Sandler was observed during January Schmadel, L. D. (1999). Dictionary of Minor Planet Names. and February of 2005. The synodic period was Springer: Berlin, Germany. 4th Edition. measured and determined to be 3.40 ± 0.01 hours with an amplitude of 0.16 magnitude. Warner, B. D. and Alan Harris, A. (2004) “Potential Lightcurve Targets 2005 January – March”, www.minorplanetobserver.com/ astlc/targets_1q_2005.htm Minor planet 4006 Sandler was discovered by the Russian astronomer Tamara Mikhailovna Smirnova in 1972. (Schmadel, 1999) It orbits the sun with an orbit that varies between 2.058 AU and 2.975 AU which locates it in the heart of the main asteroid belt.