Free Astronomy Magazine May-June 2025 ARABIC VERSION

ionizedsiliconatoms,specificallysil- is unprecedented,” says Tom Geballe, NOIRLab emeritus as- tronomer and co-author of thepaper appearing in the Monthly No- tices of the Royal Astronomical So- ciety. “And while this signal is shocking, it’s also shocking what’s not there.” Novae found in the Milky Way typi- cally emit numerous near-infrared signatures from highly-excited ele- ments, but LMC68’s spectra con- tained only the ionized silicon feature. “Wewould’veexpectedto also see signatures of highly ener- gized sulfur, phosphorus, calcium andaluminum,” saysGeballe. “This surprising absence, combined with thepresenceandgreatstrengthof the silicon signature, implied an un- usually high gas temperature, which ourmodelingconfirmed,” addsco- author Sumner Starrfield, Regents ProfessorofAstrophysicsatArizona StateUniversity.Theteamestimates that, during the nova’s early post- explosionphase,thetemperatureof the expelled gas reached 3 million degreesCelsius(5.4milliondegrees Fahrenheit), making it one of the hottest novae ever recorded. This extreme temperature suggests a highlyviolenteruption,whichthe teamtheorizesisduetothecondi- tions of the nova’s environment. The Large Magellanic Cloud and its stars have a lower metallicity than theMilkyWay,meaningitcontains a lower abundance of elements heavier than hydrogen and helium, referred to as metals by as- tronomers. In high-metallicity sys- tems,heavyelementstrapheaton thewhitedwarf’ssurfacesuchthat eruptions occur early in the accre- tion process. But without these heavy elements, more matter builds uponthewhitedwarf’ssurfacebe- fore it gets hot enough to ignite, causingtheexplosiontoeruptwith far greater violence. Additionally, the expelled gas collides with the atmosphere of the companion red subgiant,causingahugeshockthat elevatesthetemperaturesinthe collision. Prior to collecting their data, Starrfield predicted that the accretionoflow-metallicitymaterial onto a white dwarf would result in amoreviolentnovaexplosion.The observationsandanalysispresented herearebroadlyinagreementwith that prediction. “With only a small number of recur- rent novae detected within our own galaxy, understanding of these ob- jects has progressed episodically,” says Martin Still, NSF program di- rector for the International Gemini Observatory. “By broadening our range to other galaxies using the largest astronomical telescopes available, like Gemini South, as- tronomers will increase the rate of progress and critically measure the behavior of these objects in differ- entchemicalenvironments.”     ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 39 رﺻــﺪ ﻓﺮ ــﻖ ﻣــﻦ ﻋﻠﻤــﺎء اﻟﻔﻠــﻚﻷول ﻣــﺮة ﻣﺴــﺘﻌﺮ اً اً ﻣﺘﺠــﺪد ﺧــﺎرج ﻣﺠــﺮة در اﻟﺘ ﺎﻧــﺔ ﻓــﻲ ﻧﻄــﺎق اﻟﻄــﻮل اﻟﻤـــﻮﺟﻲ اﻟﻘﺮ ـــﺐ ﻣـــﻦ اﻷﺷـــ ﻌﺔ ﺗﺤـــﺖ اﻟــــ ﻤﺮاء . ﻘـــﻊ ﻫـــﺬا اﻟﻤﺴـــﺘﻌﺮ اﻟﻤﺴـــﻤﻰ LMC 1968-12 ﻓـــﻲ ﺳﺤﺎ ﺔ ﻣﺎﺟﻼن اﻟﻜ ى وﻫﻲﻣﺠﺮة ﺗﺎ ﻌﺔ ﻟﻤﺠﺮ ة در اﻟﺘ ﺎ . ﻧﺔ ـﺎً ـﻞ أرـﻊﺳـﻨﻮات ﺗﻘﺮ ﻨﻔﺠـﺮ وﻫـﻮ ﺛﺎﻟـﺚ ﻟﺘﻜــــﺮارأيﻣﺴــــﺘ أﻗﺼــــﺮﻧﻄــــﺎق زﻣــــ ﻌﺮ و ﻘــــﺪراﻟﻔﺮ ــــﻖ أﻧــــﮫ ﺧــــﻼل اﻟﻤﺮﺣﻠــــﺔ ﺗﻠــــﻲ اﻧﻔﺠــــﺎر اﻟﻤ ﻜــــﺮة اﻟــــ اﻟﻤﺴﺘﻌﺮ وﺻﻠﺖ درﺟﺔ ﺣﺮارة اﻟﻐﺎزاﻟﻤﻨ ﻌﺚ إﻟﻰ 3 درﺟﺔ ﻣﻼﻳ ) ﻣﺌﻮ ﺔ 5.4 ﻣﻠﻴﻮن درﺟﺔ ﻓﻬﺮﻬﺎ ﺖ ( ﻣﻤﺎ ﻳﺠﻌﻠﮫ أﺣﺪ أﻛ اﻟﻤﺴﺘﻌﺮاتﺳﺨﻮ ﻧﺔ ﻋﻠﻰ اﻹﻃﻼق . ﻠﺨﺺﻫﺬا اﻟﻔ ﺪﻳﻮ اﻻﻛﺘﺸﺎف . Im ges and V deos:International Gemini Observatory /NOIRLab/NSF/AURA/M.Garlick,M.Za- mani, ESO/L.Calçada ,M.Kornmesser, P.Horálek (Institute of Physics in Opava), N.Bartmann (NSFNOIRLab) − Music:Stellardrone-Airglow ﻣﻦ إﻟﻜﱰوﻧﺎﺗﻬﺎ اﻷرﺑﻌﺔ ﻋﴩـ اﻷﻣـﺮ اﻟـﺬي ﻳﺘﻄﻠﺐ ﻛﻤﻴﺎت ﻫﺎﺋﻠﺔ ﻣﻦ اﻟﻄﺎﻗﺔ ﻋﲆ ﺷﻜﻞ إﺷﻌﺎع أو ﺗﺼﺎدﻣﺎت ﻋﻨﻴﻔﺔ . ﰲ اﻟﻄﻴﻒ اﻟﺴﺎﺑﻖ ﻣﻦ ﺗﻠﺴﻜﻮب ﻣﺎﺟﻼن ﻛﺎن ﺿﻮء اﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤـﺮاء اﻟﻘﺮﻳﺒـﺔ ﻣـﻦ ا ﻟﺴﻴﻠﻴﻜﻮن ا ﺘﺄﻳﻦ وﺣﺪه أﻛﺜﺮ ﺳـﻄﻮﻋ ﺎً ﺑــ 95 ﻣﺮة ﻣﻦ اﻟﻀﻮء ا ﻨﺒﻌـﺚ ﻣـﻦ اﻟﺸـﻤﺲ ﻣُﺠﻤﱠ ﻌًﺎ ﻋﱪ ﺟﻤ ﻴﻊ أﻃﻮال ﻣﻮﺟﺎﺗﻪ ) اﻷﺷﻌﺔ اﻟﺴﻴﻨﻴﺔ واﻷﺷﻌﺔ ﻓﻮق اﻟﺒﻨﻔﺴﺠﻴﺔ واﻷﺷﻌﺔ ا ﺮﺋﻴﺔ واﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤـﺮاء واﻟﺮادﻳـﻮ .( ﻣﺎ ﻋﻨﺪ رﺻﺪ ﺟﻴﻤﻴﻨﻲ اﻟﺨﻂ ﺑﻌﺪ ﻋـﺪة أﻳـﺎم ﺗﻼﺷﺖ اﻹﺷﺎرة ﻟﻜﻦ اﻧﺒﻌﺎث اﻟﺴـﻴﻠﻴﻜﻮن ﻻ ﻳﺰال ﻳﻬﻴﻤﻦ ﻋﲆ اﻟﻄﻴﻒ . ﻳﻘﻮل ﺗﻮم ﺟﻴﺒﺎل ﻋـﺎﻟﻢ اﻟﻔﻠـﻚ اﻟﻔﺨـﺮي ﰲ ﻣﺨﺘﱪ ﻧﻮﻳﺮﻻب وا ﺆﻟـﻒ ا ﺸـﺎرك ﻟﻠﻮرﻗـﺔ اﻟﺒﺤﺜﻴﺔ اﻟﺘﻲ ﻧُﴩت ﰲ اﻹﺷﻌﺎرات اﻟﺸﻬﺮﻳﺔ ﻟﻠﺠﻤﻌﻴــﺔ اﻟﻔﻠﻜﻴــﺔ ا ﻠﻜﻴــﺔ " : إن ﺗــﺄﻟﻖ اﻟﺴﻴﻠﻴﻜﻮن ا ﺘﺄﻳﻦ ﺑﻤﺎ ﻳﻘﺮب ﻣﻦ 100 ﻣـﺮة أﻛﺜ ـﺮ ﺳـﻄﻮﻋًﺎ ﻣ ـﻦ اﻟﺸـﻤﺲ أﻣ ـﺮ ﻏ ـ . "" ﻣﺴﺒﻮق ورﻏﻢ أن ﻫﺬه اﻹﺷﺎرة ﺻـﺎدﻣﺔ إﻻ أن ﻣﺎ ﻫﻮ ﻏ ﻣﻮﺟﻮد ﻫﻮ ﺻﺎدم أﻳﻀًﺎ ". ﻋﺎدةً ﻣﺎ ﺗﺼﺪر ا ﺴﺘﻌﺮات اﻟﺠﺪﻳﺪة ا ﻮﺟﻮدة ﰲ ﻣﺠﺮة درب اﻟﺘﺒﺎﻧﺔ اﻟﻌﺪﻳﺪ ﻣﻦ اﻟﺘﻮﻗﻴﻌﺎت اﻟﻘﺮﻳﺒﺔ ﻣﻦ اﻷﺷـﻌﺔ ﺗﺤـﺖ ا ﻟﺤﻤـﺮاء ﻣـﻦ اﻟﻌﻨﺎﴏﺷﺪﻳﺪة اﻹ ﺛﺎرة ﻟﻜﻦ أﻃﻴﺎف ا ﺴﺘﻌﺮ LMC68 اﺣﺘــﻮت ﻓﻘــﻂ ﻋــﲆ ﺧﺎﺻــﻴﺔ اﻟﺴﻴﻠﻴﻜﻮن ا ﺆﻳﻦ . ﻳﻘـﻮل ﺟﻴﺒـﺎل " : ﻛﻨـﺎ ﻧﺘﻮﻗـﻊ أﻳﻀًـﺎ رؤﻳـﺔ ﺗﻮﻗﻴﻌﺎت ﻟﻠﻜﱪﻳﺖ واﻟﻔﻮﺳﻔﻮر واﻟﻜﺎ ﻟﺴﻴﻮم واﻷﻟﻮﻣﻨﻴﻮم ﻋﺎﻟﻴﺔ اﻟﻄﺎﻗﺔ " وﻳﻀﻴﻒ ا ﺆﻟﻒ ا ﺸﺎرك ﺳﻮﻣﻨﺮ ﺳﺘﺎرﻓﻴﻠﺪ، أﺳﺘﺎذ اﻟﻔﻴﺰﻳـﺎء اﻟﻔﻠﻜﻴﺔ ﰲ ﺟﺎﻣﻌـﺔ وﻻ ﻳـﺔ أرﻳﺰوﻧـﺎ " : ﻫـﺬا اﻟ ﻐﻴﺎب ا ﻔﺎﺟﺊ إﱃ ﺟﺎﻧﺐ و ﺟﻮد وﻗﻮة ﻛﺒ ة ﻟﺘﻮﻗﻴﻊ اﻟﺴﻴﻠﻴﻜﻮن ﻳﻌﻨﻲ درﺟ ﺔ ﺣﺮارة ﻏـﺎز ﻋﺎﻟﻴﺔ ﺑﺸﻜﻞ ﻏ ﻋـﺎدي وﻫـﻮ ﻣـﺎ أﻛﺪﺗـﻪ ﻧﻤﺬﺟﺘﻨﺎ ." ﻳﻘﺪر اﻟﻔﺮﻳﻖ أﻧﻪ ﺧﻼل ﻣﺮﺣﻠﺔ ﻣﺎ ﺑﻌﺪ اﻧﻔﺠﺎر ا ﺴﺘﻌﺮات ا ﺒﻜﺮة وﺻﻠﺖ درﺟﺔ ﺣﺮارة اﻟﻐﺎز ا ﻘـﺬوف إﱃ 3 ﻣﻼﻳـ درﺟـﺔ ) ﻣﺌﻮﻳﺔ 5.4 ﻣﻠﻴﻮن درﺟﺔ ﻓﻬﺮﻧﻬﺎﻳﺖ ( ﻣﻤـﺎ ﻳﺠﻌﻠﻪ أﺣﺪ أﻛﺜﺮ ا ﺴـﺘﻌﺮات ﺳـﺨﻮﻧﺔ ﻋـﲆ اﻹﻃﻼق . ﺗﺸ ﻫـﺬه اﻟﺤـﺮارة اﻟﺸـﺪ ﻳﺪة إﱃ ﺛﻮران ﺑﺮﻛﺎﻧﻲ ﺷﺪﻳﺪ اﻟﻌﻨﻒ واﻟﺬي ﻳُﻔـﱰض أن ﻳﻜﻮن ﻧﺘﻴﺠﺔً ﻟﻈﺮوف ﺑﻴﺌﺔ اﻟﻨﺠﻢ اﻟﺠﺪﻳ .ﺪ ﺗﺘﻤﻴﺰ ﺳﺤﺎﺑﺔ ﻣـﺎﺟﻼن اﻟﻜـﱪى وﻧﺠﻮﻣﻬـﺎ ﺗﺘﻤﻴﺰ ﺳﺤﺎﺑﺔ ﻣـﺎﺟﻼن اﻟﻜـﱪى وﻧﺠﻮﻣﻬـﺎ ﺑﱰﻛﻴﺒﺔ ﻣﻌﺪﻧﻴﺔ أﻗﻞ ﻣﻦ ﻣﺠﺮة درب اﻟﺘﺒﺎﻧﺔ ﻣﻤﺎ ﻳﻌﻨﻲ أﻧﻬﺎ ﺗﺤﺘﻮي ﻋﲆ وﻓﺮة أﻗـﻞ ﻣـﻦ اﻟﻌﻨﺎﴏ اﻷﺛﻘﻞ ﻣﻦ اﻟﻬﻴﺪروﺟ واﻟﻬﻴﻠﻴﻮم، واﻟ ﺘـﻲ ﻳُﻄﻠـﻖ ﻋﻠﻴﻬـﺎ ﻋﻠﻤـﺎء اﻟﻔﻠـﻚ اﺳـﻢ ا ﻌﺎدن . ﰲ اﻷﻧﻈﻤﺔ ﻋﺎﻟﻴﺔ اﻟﱰﻛﻴﺐ ا ﻌـﺪﻧﻲ ﺗﺴﺨﻦ اﻟﻌﻨﺎ ﴏ اﻟﺜﻘﻴﻠﺔ ﻋﲆ ﺳﻄﺢ اﻟﻘـﺰم اﻷﺑﻴﺾ ﻣﻤﺎ ﻳﺆدي إﱃ ﺣﺪوث ﺛﻮر ات ﰲ وﻗﺖ ﻣﺒﻜﺮ ﻣﻦ ﻋﻤﻠﻴﺔ اﻟﱰاﻛﻢ وﻟﻜﻦ ﺑـﺪون ﻫـﺬه اﻟﻌﻨﺎﴏ اﻟﺜﻘﻴﻠﺔ ﻳ ﱰاﻛﻢ ا ﺰﻳﺪ ﻣﻦ ا ﺎ دة ﻋﲆ ﺳﻄﺢ اﻟﻘﺰم اﻷﺑﻴﺾ ﻗﺒـﻞ أن ﻳﺴـ ﺨﻦ ﺑﻤـﺎ ﻳﻜﻔﻲ ﻟﻼﺷﺘﻌﺎل ﻣﻤﺎ ﻳﺘﺴﺒﺐ ﰲ اﻧﻔ ﺠﺎر أﺷﺪ . ﻋﻨﻔًﺎ ﺑﺎﻹﺿـﺎﻓﺔ إﱃ ذﻟـﻚ ﻳﺼـﻄﺪم اﻟﻐـﺎز ا ﻨﺒﻌﺚ ﺑﺎﻟﻐﻼف اﻟﺠﻮي ﻟ ﻠﻨﺠﻢ ﺷﺒﻪ اﻟﻌﻤﻼق اﻷﺣﻤﺮ ا ﺮاﻓﻖ ﻣﻤﺎ ﻳُﺴـﺒﺐ ﺻـﺪﻣﺔ ﻫﺎﺋﻠـﺔ ﺗﺮﻓﻊ درﺟﺎت اﻟﺤﺮارة أ ﺛﻨﺎء اﻻﺻﻄﺪام . ﻗﺒﻞ ﺟﻤﻊ ﺑﻴﺎﻧﺎﺗﻬﻢ ﺗﻮﻗـﻊ ﺳـﺘﺎرﻓﻴﻠﺪ أن ﺗـﺮاﻛﻢ ا ﻮاد ا ﻌﺪﻧﻴﺔ ا ﺘﺪﻓﻘـﺔ ﻋـﲆ ﻗـﺰم أﺑـﻴﺾ ﺳﻴﺆدي إﱃ اﻧﻔﺠﺎر ﻧﺠﻢ ﺟﺪﻳﺪ أﻛﺜـﺮ ﻋﻨﻔًـﺎ . ﺳﻴﺆدي إﱃ اﻧﻔﺠﺎر ﻧﺠﻢ ﺟﺪﻳﺪ أﻛﺜـﺮ ﻋﻨﻔًـﺎ . وﺗﺘﻔﻖ ا ﻼﺣﻈﺎت واﻟﺘﺤﻠﻴﻼت ا ﻘﺪﻣﺔ ﻫﻨـﺎ ﺑﺸﻜﻞ ﻋﺎم ﻣﻊ ﻫﺬا اﻟﺘﻮﻗﻊ . ﻳﻘﻮل ﻣﺎرﺗﻦ ﺳﺘﻴﻞ، ا ﺪﻳﺮ ا ـﻮﻗﺮ ﻟﱪﻧـﺎﻣﺞ ﻣﺆﺳﺴﺔ اﻟﻌﻠﻮم اﻟﻮﻃﻨﻴﺔ ﰲ ﻣﺮﺻﺪ ﺟﻴﻤﻴﻨﻲ اﻟﺪوﱄ، ﻣﻌﱪاً ﻋﻦ أﻫﻤﻴﺔ اﻻﻛﺘﺸـﺎف " : ﻣـﻊ اﻛﺘﺸـﺎف ﻋـﺪد ﻗﻠﻴـﻞ ﻓﻘـﻂ ﻣـﻦ اﻟﻨﺠـﻮ م اﻟﺠﺪﻳﺪة ا ﺘﻜﺮرة اﻟﺘﻲ ﺗـﻢ ﺗﺤﺪﻳـﺪﻫﺎ ﺑﺪﻗـﺔ داﺧﻞ ﻣﺠﺮﺗﻨﺎ ﻓﻘﺪ ﺷﻬﺪ ﻓﻬﻤﻨﺎ اﻟﻌﻤﻴﻖ ﻟﻬﺬه اﻷﺟﺮام اﻟﺴﻤﺎوﻳﺔ اﻟﻐﺎﻣﻀﺔ ﺗﻘﺪﻣﺎً ﻣﻠﺤﻮﻇﺎً ﻳﻀـﻴﻒ ﻗـﺎﺋﻼً ﺑﺘﻔـﺎؤل " : ﺑﺘﻮﺳـﻴﻊ ﻧﻄــﺎق اﺳﺘﻜﺸﺎﻓﻨﺎ ﻟﻴﺸﻤﻞ ﻣﺠﺮات أﺧـﺮى ﺑﻌﻴـﺪة ﺑﺎﺳﺘﺨﺪام أﻗﻮى وأﻛﱪ اﻟﺘﻠﺴﻜﻮﺑﺎت اﻟﻔﻠﻜﻴﺔ ا ﺘﺎﺣـﺔ ﺣﺎﻟﻴـﺎً، ﻣﺜـﻞ ﺗﻠﺴـﻜﻮب ﺟﻴﻤﻴﻨـﻲ ﺳﺎوث اﻟﻌﻤﻼق ﺳﻨﺘﻤﻜﻦ ﺑﻼ ﺷﻚ ﻣﻦ زﻳﺎدة ﻣﻌﺪل ﻫﺬا اﻟﺘﻘﺪم اﻟﻌﻠﻤـﻲ ﺑ ﻘﻴـﺎس ﺳـﻠﻮك اﻷﺟﺮام ﻫﺬه اﻟ ﺴﻤﺎوﻳﺔ ﰲ ﺑﻴﺌـﺎت ﻛﻴﻤﻴﺎﺋﻴـﺔ ﻣﺨﺘﻠﻔﺔ وﻣﺘﻨﻮﻋﺔ ﺑﺸﻜﻞ ﻣﻠﺤﻮظ ." ﻣﺎﻳﻮ - ﻳﻮﻧﻴﻮ 2 0 2 5