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Objekti Globoko V Vesolju Oktobra Je Posnel Hubblov Teleskop

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Objekti Globoko V Vesolju Oktobra Je Posnel Hubblov Teleskop Interno glasilo Astronomskega druˇstva Javornik Stevilkaˇ 152, Letnik XIII, September 2012 www: http://www.adj.si, email: [email protected] ISSN 1581-1379 Objekti globoko v vesolju oktobra je posnel Hubblov teleskop. V resnici smo videli nekaj, ˇcesarHubble ne pokaˇze: tam, kjer je Hubblova slika V zaˇcetkuoktobra nastopi astronomska tema ob 20:21 preˇzgana,smo videli, kako se jedro boˇcinad ozadjem in traja 9:01 ur, na koncu se zaˇcneob 18:30 in traja starih zvezd na prehodu iz jedra v spiralna kraka, po skoraj deset ur in pol. Astronomski mrak v tem mesecu krakih pa so bile zelo lepo videti kopice pravkar rojenih traja 35 minut. Ko se znoˇci,so poletna ozvezdja ˇse zvezd safirne barve in seveda ˇstevilne porodniˇsnice vedno na nebu, do jutra pa vzidejo zimska. zvezd, ki so bile videti kot rubini, rjavkasti oblaki Oktobra opolnoˇcikulminirajo ozvezdja Kasiopeja medzveznega prahu pa so se z ukrivljenimi koniˇcastimi z razsutimi kopicami NGC 129*, NGC 457*, NGC jeziki zajedali daleˇcv jedro. 205, M 103 (NGC 581), NGC 663*, Collinder 463*, Stock 2*, Markarian 6*, Melotte 15*, Trumpler 3*, M 52 (NGC 7654) in NGC 7789*, Andromeda z galak- Trikotnik sijo M 31* (NGC 224) s spremljevalkama M 32* (NGC 221) in M 110 (NGC 205), razsuto kopico NGC 752* in Tudi M33 je ˇclanicalokalne jate, oddaljena tri mili- planetarno meglico NGC 7662*, Trikotniku z galak- jone svetlobnih let. Je najmanjˇsamed tremi velikimi, sijo M33 (NGC 598), Ribi z galaksijo M74 (NGC 628), vidimo jo zvrha, a ker je blizu, jo s temnega opa- Kit z galaksijo M77* (NGC 1068) in Kipar z galaksijo zovaliˇsˇcaopazimo tudi s prostimi oˇcmi,ˇceprav njen NGC 253. Rimska cesta se boˇciˇceznebo od vzhoda povrˇsinskisij ni velik. Binokular in manjˇsiteleskop ˇze do zahoda in je ˇsevedno v ugodni legi za opazovanje z pokaˇzetanjen obris, dober ogled nudi teleskop z ob- binokularjem. Zvezdica oznaˇcujeobjekte, ki se jih da jektivom 25 cm ali veˇc.Pri emisijski meglici NGC 604 opazovati z opazovaliˇsˇc,kjer nebo ni temno. na vrhu njenega severnega kraka si lahko pomagamo s filtrom za meglice, ki bo poveˇcalkontrast s tem, da bo Kasiopeja priduˇsilsvetlobo zvezd. NGC 129, razsuta kopica, je s temnega opazovaliˇsˇca opazna celo sprostimi oˇcmi,v binokularju je videti kot Ribi majhen trikotnik zvezd, v teleskopu pa se prikaˇzeprecej ˇsibkejˇsih,ki iz trikotnika uhajajo proti severu. NGC Galaksija M74 (NGC 628) ima na videz zelo ma- 457 se je splaˇcapogledati skozi teleskop: ovalna je in jhno jedro: v majhnih daljnogledih ga komaj loˇcimo dve svetli zvezdi, ki sicer nista ˇclanicirazsute kopice, od zvezde, a ˇze objektiv premera 10 cm v ugod- svetita kot oˇcisove, zato jo Anglosasi imenujejo Kopica nih razmerah daje slutiti spiralno zgradbo, s 40 cm sova. pa v jasno vidnih spiralnih krakih lepo loˇcimo vozle svetlejˇsihsvezd in zvezdne oblake v tej galaksiji. V Andromeda resnici je 55 milijonov svetlobnih let daleˇcin ima pre- mer 95 tisoˇcsvetlobnih let. Jedro je majhno, a svetlo, Najsvetlejˇsagalaksija (ˇcene ˇstejemonaˇseGalaksije), sama galaksija pa je lepo simetriˇcna. kar jih vidimo, je Andromedina meglica, ˇclanicalokalne jate, ki je oddaljena 2,5 milijona svetlobnih let. Ni jasno, ali je veˇcjaod naˇseGalaksije ali ne, in tudi ne, Kit ali ima tako kot naˇsa preˇcko ali ne, ima pa dvojno jedro, kar je najbrˇzposledica tega, da okoli njene ˇcrne Spiralna galaksija M77 (NGC 1068) je 60 milijonov luknje kroˇziprecjˇsnjaskupina zvezd v nasprotni smeri, svetlobnih let daleˇc,svetlejˇsidel, bogat z mladimi zvez- kot ostale. Je pa ˇzejasno, da je verjetnost 41%, da dami, ima premer 120, ˇsibkejˇsi,v katerem moˇcno pre- bosta ti dve galaksiji ˇcelnotrˇciliˇcez 4 miljarde let in vladujejo starejˇsezvezde, pa 170 tisoˇcsvetlobnih let. bosta 2 miljardi let kasneje ˇzezliti v veliko eliptiˇcno Svetlejˇsidel ima maso 27 milijard sonc, celotna galak- galaksijo. Verjetnost, da se zgreˇsitaje 7%, malo veˇcja, sija pa bilijon. Iz jedra beˇzijoplini s hitrostjo nekaj sto 9%, pa je, da bo z naˇsogalaksijo prej trˇcilaM 33. kilometrov na sekundo in oddajajo spekter, ki spom- A do takrat, kadar je ozraˇcjeres izjemo prozorno, inja na tistega, ki ga oddajajo planetarne meglice, kar nam nudi pogled, ki smo ga doˇziveli vsi udeleˇzenci to galaksijo uvrˇsˇcamed Seifertove galaksije. Jedro je tabora Kavka 2005: v binokularju 20×100 slika ni za- moˇcanvir radijskega in infrardeˇcegasevanja, kar si ostajala ne po barvah, ne po podrobnostih za tisto, ki jo lahko razlagamo s tem, da tam deluje majhen kvazar. VABILO Vabimo vas na meseˇcnisestanek, ki bo v torek 18. 09. 2012 ob 18h v predavalnici F4 Fakultete za matematiko in fiziko, Jadranska 19, v Ljubljani. Na meseˇcnemsestanku nam bo Rok Vidmar predstavil zanimivosti noˇcneganeba v tekoˇcemin prihodnjem mesecu. Nato se bomo dogovorili za meseˇcnodruˇstveno opazovanje, ki ga bomo izvedli v okolici Ljubljane. Vsi ˇclanidruˇstva ste vabljeni, da se nam pridruˇzite.V kolikor bi se radi udeleˇziliopazovanja, pa vas ne bo na sestanku, mi to prosim sporoˇcitepo e-poˇstina naslov [email protected]. Vabljeni! Bernard Kipar ? Uran je v zaˇcetkuoktobra na nebu vso noˇc,nato pa zahaja vse bolj zgodaj in konec meseca zaide Galaksija NGC 253 sodi med najsvetlejˇsena naˇsem okoli petih zjutraj. Nahaja se v ozvezdju Rib. nebu. Od nas je, skupaj z ostalimi ˇclanicami jate v tem ozvezdju, oddaljena 8 milijonov svetlobnih let, v Ostalo: njej je izjemno veliko medzvezdnega prahu in zvezde v ? V noˇcis 27. na 28. oktober premaknemo ure za njej nastajajo s tako vrtoglavo hitrostjo, da se v njenem eno uro nazaj. centru utegne narediti dovolj velika ˇcrnaluknja, da bo UrˇskaPajer sproˇzilakvazar. Rok Vidmar E-poˇstni seznam slo-astro Efemeride oktober 2012 Slovenski amaterski astronomi komuniciramo tudi preko poˇstnegaseznama (\mailing liste") slo-astro, (Efemeride si lahko ogledate tudi v reviji Zivljenjeˇ in tehnika.) kjer si izmenjujemo prispevke vseh vrst: opozo- Sonce Luna rila o zanimivih astronomskih dogodkih in prired- datum vzhod zahod vzhod zahod ˇcas itvah, vabila na opazovanja, poroˇcila o opazovan- 01.10. 07:01 18:42 19:01 08:21 CEST jih, vpraˇsanja, ponudbo rabljene opreme itd. Pri- 05.10. 07:06 18:34 21:27 12:15 CEST javi se lahko vsak, dodatne informacije in prijava na 10.10. 07:12 18:25 01:15 15:32 CEST http://www.adj.si/slo-astro. Trenutno ima lista 15.10. 07:19 18:15 07:12 18:00 CEST 114 ˇclanov. 20.10. 07:26 18:07 12:58 22:24 CEST Aram Karaliˇc 25.10. 07:33 17:58 15:46 02:59 CEST 30.10. 06:40 16:50 17:05 07:14 CET Planeti: ? Merkur oktobra ni viden. Objavite prispevek! ? Venera sprva vzhaja okoli pol ˇstirihzjutraj, nato Meseˇcnik potrebuje prispevke. Zato pozivam vse, pa vse kasneje in konec meseca vzide ob pol petih. ki ˇzelite kaj objaviti, da mi po elektronski poˇsti Sredi meseca se iz ozvezdja Leva preseli v ozvezdje poˇsljetesvoj prispevek. Prispevki so lahko raznovrstni: Device. poroˇciloo opazovanju, slika, risba, zanimiva astronom- ? Mars je viden zveˇcer,ko zahaja slabi dve uri za ska novica, predstavitev domaˇcega observatorija ali Soncem. V zaˇcetkumeseca se iz ozvezdja Tehtnice teleskopa, skratka { karkoli astronomskega. ˇ preseli v ozvezdje Skorpijona. Aram Karaliˇc ? Jupiter v ozvezdju Bika sprva vzhaja okoli pol desetih, nato pa vse bolj zgodaj in je konec meseca JavorniˇskiMeseˇcnikizdaja Astronomsko druˇstvo Javornik, Ljubl- na nebu ˇzeob pol osmih. jana / ISSN 1581-1379 / urednik Aram Karaliˇc / izhaja v prvi ? Saturn morda v ozvezdju Device ˇseujamemo v polovici meseca / prejemajo ga brezplaˇcno vsi ˇclaniAstronomskega druˇstva Javornik / prispevke poˇsljitena naslov [email protected] / ROK zaˇcetkumeseca, ko zahaja slabo uro za Soncem, ZA ODDAJO PRISPEVKOV JE 7. DAN V MESECU / potem pa ni veˇcviden. prispevkov praviloma ne lektoriramo / stavljeno v LATEXu.
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