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Zvaigžņotā Debess ZVAIGÞÒOTÂ ZVAIGÞÒOTÂ DEBESS 2003 DEBESS VASARA 28. AUGUSTÂ MARSS LIELAJÂ OPOZÎCIJÂ PAVADOÒU LÂZERLOKÂCIJA LATVIJAS UNIVERSITÂTÇ “COLUMBIA” BOJÂEJA. Kas un kâpçc? Plâna Zemes horizonta ðíçle, kas redzama no SAULES APTUMSUMI RÎGÂ kosmoplâna “Space Shut- tle Columbia” 2003. gada kopð PILSÇTAS DIBINÂÐANAS 18. janvârî. NASA/“Shuttle” attçls Sk. J. Jaunberga rakstu “Pârdomas pçc “Columbia” bojâejas”. JAUNS ZVAIGZNÂJS LATVIJAS AVÎÞZIÒÂ! Pielikumâ – MARSA TOPOGRÂFISKÂ KARTE Ðo saulrietu virs Sahâras tuksneða fotografçjuði STS-111 apkalpes locekïi no kosmoplâna “Space Shuttle Endeavour” (2002. gada 5.–19. jûnijs). Fotografçðanas laikâ “Shuttle” atradâs virs Sudânas Sarkanâs jûras krasta tuvumâ. NASA/“Shuttle” attçls Sk. J. Jaunberga rakstu “Pârdomas pçc “Columbia” bojâejas”. LU Astronomijas institûta satelîtu dienesta darba grupa pie LS-105 lâzerteleskopa 2002. gada vasarâ. No kreisâs: dienesta vadîtâjs vad. pçtnieks Dr. phys. K. Lapuðka, pçtnieki Mc. sc. I. Abakumovs un Mc. sc. V. Lapoðka. K. Salmiòa foto Sk. I. Abakumova rakstu “Satelîtu lâzerlokâcija Latvijâ”. Vâku 1. lpp.: “Mars Smart Lander” nolaiðanâs beigu posms. JPL zîmçjums Sk. J. Jaunberga rakstu “Neizbraucamais Marss”. SATURS Pirms 40 gadiem Zvaigþòotajâ Debesî ZVAIGÞÒOTÂ Ðmidta teleskopi un Galaktikas pçtîjumi. Bulîðu meteorîtam 100 gadu..................................................2 Zinâtnes ritums DEBESS Meklçjot neredzamo. Dmitrijs Docenko................................3 Jaunumi Iespçjams kosmoloìisko gamma staru uzliesmojumu modelis. Arturs Balklavs.....................................................9 LATVIJAS ZINÂTÒU AKADÇMIJAS, Pieaug melno caurumu kandidâtu pulks. LATVIJAS UNIVERSITÂTES Arturs Balklavs.....................................................................11 ASTRONOMIJAS INSTITÛTA Z Ursae Minoris un RCB fenomens. Arturs Barzdis..........14 Kosmosa pçtniecîba un apgûðana POPULÂRZINÂTNISKS Pârdomas pçc Columbia bojâejas. Jânis Jaunbergs.........18 GADALAIKU IZDEVUMS Columbia traìçdija. Kas un kâpçc notika? Mârtiòð Sudârs....................................................................22 IZNÂK KOPÐ 1958. GADA RUDENS Satelîtu lâzerlokâcija Latvijâ. Igors Abakumovs...................25 ÈETRAS REIZES GADÂ Latvijas zinâtnieki Zenta Alksne jubilâre.........................................................29 Mans mûþs astronomijâ. Zenta Alksne...............................30 Latvijas Universitâtes mâcîbu spçki 2003. GADA VASARA (180) LU Astronomiskâs observatorijas dibinâtâjam profesoram Alfrçdam Þageram 125. Jânis Klçtnieks........37 Astronomam Matîsam Dîriíim 80...................................43 Atceroties Matîsu Dîriíi. I. Daube, I. Platais, N. un L. Èernihi, B. Mârsdens, D. Draviòð, J. Balodis, J. Kauliòð...........................................................45 Konferences un sanâksmes Astronomija LU 61. konferencç. Arturs Balklavs.................61 Atziòu ceïi Daþi Universa tâlâs nâkotnes jeb eshatologijas jautâjumi. Imants Vilks........................................................64 Skolâ Redakcijas kolçìija: Latvijas 53. matemâtikas olimpiâde. Agnis Andþâns...........67 Jauns zvaigznâjs RCW 38. Andrejs Alksnis.......................69 A. Alksnis, A. Andþâns (atbild. red. Marss tuvplânâ vietn.), A. Balklavs (atbild. redaktors), Neizbraucamais Marss. Jânis Jaunbergs..............................71 Lielâkâ no lielajâm Marsa opozîcijâm! Juris Kauliòð............76 K. Bçrziòð, M. Gills, R. Kûlis, Amatieriem I. Pundure (atbild. sekretâre), Sudrabainie mâkoòi. Jânis Blûms.....................................78 T. Romanovskis, L. Roze, I. Vilks Jaunas grâmatas Grâmata par dzîvîbas meklçjumiem Visumâ. Tâlrunis 7034580 Arturs Balklavs.....................................................................82 E-pasts: [email protected] Kosmosa tçma mâkslâ http://www.astr.lu.lv/zvd Oïega Visocka gleznas Pçterbaznîcâ. Natâlija Cimahovièa.........................................................85 Hipotçþu lokâ Dainâs slçptâ informâcija. Natâlija Cimahovièa...............86 Hronika Astronomijas institûts 2002. gadâ. Arturs Balklavs............88 Ierosina lasîtâjs Rîga, 2003 Saules aptumsumi Rîgâ (12012200). Kazimirs Lapuðka, Igors Abakumovs................................90 Iespiests LatvijasSomijas SIA Jautâ lasîtâjs Par plançtu X jeb 15. maija saulrietu. Arturs Balklavs.....94 Madonas poligrâfists, Madonâ, Zvaigþòotâ debess 2003. gada vasarâ. Juris Kauliòð.........96 Saieta laukumâ 2a, LV-4801 Pielikumâ: Marsa topogrâfiskâ karte 1 PIRMS 40 GADIEM ZVAIGÞÒOTAJÂ DEBESÎ ÐMIDTA TELESKOPI UN GALAKTIKAS PÇTÎJUMI Divdesmito gadu beigâs Bernhards Ðmidts jau bija pazîstams kâ labs astronomisko spoguïu un lçcu slîpçtâjs. Kad Hamburgas observatorijas direktors profesors R. Ðors (R. Schorr) viòu toreiz ierosinâja izgatavot spoguïteleskopu ar lielu gaismas spçju un lielu redzes lauku fotogrâfiskiem debess novçro- jumiem, viòð diez vai cerçja, ka optikas meistara pûles bûs tik veiksmîgas. 1930. gadâ izgatavotajam pirmajam Ðmidta sistçmas teleskopam relatîvais atvçrums (d:f) ir 1:1,74, bet derîgais redzes lauks uz izliektas filmas ir 16o diametrâ. Ðâds rezultâts pârsteidza visas pasaules speciâlistus: tas, pçc kâ daudzus gadus bija centuðies optiíi apvienot vienâ teleskopâ refraktoru jeb lçcu teleskopu un reflektoru jeb spoguïteleskopu vçrtîgâkâs îpaðîbas , bija panâkts. Ar B. Ðmidta izgudrojumu radâs îstais instruments debess spîdekïu masveida novçrojumiem. Galvenais uzdevums, ko veic ar Ðmidta teleskopiem, ir mûsu Galaktikas uzbûves pçtîðana. Galaktikâ ir ap 150 miljardiem zvaigþòu, katrai no tâm ir savas individuâlâs îpaðîbas, un pçc to îpaðîbâm vairâkumu zvaigþòu var iedalît vienâ no daþiem desmitiem galveno tipu. Jau 20 gadu Vornera un Sveizija observatorijas (Klîvlenda, ASV) Ðmidta teleskops (61/91/213) kombinâcijâ ar 4o objektîva prizmu tiek izmantots zvaigþòu spektru uzòemðanai tuvâ infrasarkanajâ spektra daïâ viïòa garums 68008800 À. Lielais redzes lauks ar skaidriem zvaigþòu attçliem ðîs Ðmidta teleskopa izcilâs îpaðîbas varçtu tikt sekmîgi izmantotas arî zvaigþòu koordinâtu precîzai noteikðanai. Hamburgas observatorijas lielais Ðmidta teleskops ir izrâdîjies noderîgs arî astrometrijâ. Jâsecina, ka ar Ðmidta teleskopiem var veikt vispusîgus mûsu zvaigþòu sistçmas uzbûves pçtîjumiem nepiecieðamos mçrîjumus un novçrojumus. Apskatîtâ teleskopa tipa iespçjas zîmîgi raksturojis Ham- burgas observatorijas lîdzstrâdnieks H. Hafners (H. Haffner): Ðmidta teleskops ir tik spçcîgs instruments, ka pat viduvçjâ klimatâ tas spçj dot milzîgu materiâla bagâtîbu. Vienâ naktî uzòemtas divdesmit plates ar tajâs ietilpstoðâs informâcijas pârpilnîbu spçj nodarbinât astronomu vairâkus mçneðus vai pat gadus. (Saîsinâti pçc A. Alkðòa raksta, 10.18. lpp.) BULÎÐU METEORÎTAM 100 GADU 1863. gada 2. jûnijâ ap pusastoòiem no rîta meteorîts nokrita Augðzemç, apmçram 3 km uz dienvidiem no Jçkabpils, Bulîðu meþniecîbas teritorijâ. Debesis bijuðas klâtas augstiem spalvugubu mâkoòiem (aitiòâm). Pçkðòi dienvidaustrumu virzienâ apmçram 40o augstumâ virs horizonta bijis dzirdams neparasts troksnis, it kâ bungu rîboòa. Pçc tam gandrîz 30 s turpinâjies it kâ pçrkona grâviens. Ðajâ laikâ 11 gadus vecais ganu zçns Mârtiòð Gçrings redzçjis nokrîtam paðu meteorîtu. Tas bija nokritis uzartâ un noecçtâ laukâ. Izsistâ bedre nebija perpendikulâra attiecîbâ pret zemes virsmu, bet gan slîpa rietumuaustrumu virzienâ, ap 1,5 pçdas (ap 0,5 m) dziïa. Daïa no ðî meteorîta (59,750 g) nokïuva Jelgavas muzejâ, bet pârçjais gabals (4365,425 g) Tartu Universitâtes mineraloìiskajâ kabinetâ. Pçc íîmiskâ sastâva Bulîðu meteorîts ir tipisks akmens meteorîts. To veido galvenokârt (88%) olivîns un ðepardîts. Ðajâ masâ nevienmçrîgi izkaisîti mazi, apmçram 1 mm diametrâ, spîdoði meteorîtu dzelzs graudiòi. Meteorîta vidçjais îpatnçjais svars vienlîdzîgs 3,532. (Saîsinâti pçc I. Daubes raksta, 40.41. lpp.) 2 ZVAIGÞÒOTÂ DEBESS: 2003. GADA VASARA ZINÂTNES RITUMS DMITRIJS DOCENKO MEKLÇJOT NEREDZAMO 1. IEVADS iegûst informâciju par masas sadalîjumu ga- laktikâ. Punktveida centrâlajai masai ðî âtruma Cilvçces vçsturç ir bijuði daudzi gadîjumi, kad atkarîba no attâluma (t. s. rotâcijas lîkne) ir acîmredzamie atzinumi izrâdîjuðies nepareizi. dilstoða, bet viendabîgam vielas blîvumam Jautâjums par to, no kâ sastâv Visums, ir viens lineâri augoða atkarîbâ no attâluma. Tâpçc no ðiem piemçriem. Senie cilvçki, ar Visumu sa- reâlas galaktikas rotâcijas lîkne maziem attâ- protot Zemi, domâja, ka tas sastâv no viòiem lumiem (kur zvaigþòu blîvums ir liels) ir au- pierastajâm vielâm un priekðmetiem. Pçc tam, kad goða, bet lieliem attâlumiem tai ir jâbût dilsto- tika noskaidrots Saules un citu zvaigþòu sastâvs, ðai (jo visa galaktika pievelk tâlo zvaigzni kâ zinâtnieki pieòçma viedokli, ka gandrîz visa viela viena punktveida masa). ir ûdeòradis un hçlijs, bet mums pierastie elementi No daudzu spirâlo galaktiku novçrojumiem dzelzs, ogleklis, skâbeklis, slâpeklis veido tikai ir zinâms, ka lieliem attâlumiem lîdz galaktiku niecîgu Visuma masas daïu. Mûsdienâs tika atklâts, centram zvaigþòu kustîbas âtrumi praktiski ka arî ðis viedoklis ir aplams. Izrâdîjâs, ka domi- nesamazinâs (sk. 1. zîm.). Tas liecina, ka bez nçjoðo masas daïu veido tâda viela, ko mçs pat redzamâs vielas galaktikâs pastâv arî tumðâ nevaram ieraudzît. matçrija, kas veido ap tâm halo. Saskaòâ ar eksperimentâliem datiem kopçjo Galaktiku iekðienç tumðâ matçrija visdrîzâk Metagalaktikas matçrijas un enerìijas blîvumu sastâv no ïoti blâvâm zvaigznçm, tâdâm kâ veido parastâ matçrija (barionu viela), nezinâmâ baltie vai pat melnie punduri. Par balto punduri tumðâ
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