Free Astronomy Magazine July-August 2024 ARABIC VERSION

in a violent manner, creating a mag- netic star and throwing out some material, which created the nebula. The more distant star formed a new orbit with the newly merged, now- magnetic star, creating the binary we see today at the centre of the nebula.” “The merger scenario was already in my head back in 2017 when I stud- ied nebula observations obtained with the European Space Agency’s Herschel Space Telescope,” adds co- author Laurent Mahy, currently a senior researcher at the Royal Ob- servatory of Belgium. “Finding an age discrepancy between the stars suggests that this scenario is the most plausible one and it was only possible to show it with the new ESO data.” This scenario also explains why one of the stars in the system is mag- netic and the other is not — an- other peculiar feature of HD 148937 spotted in the VLTI data. At the same time, it helps solve a long- standing mystery in astronomy: how massive stars get their magnetic fields. While magnetic fields are a common feature of low-mass stars like our Sun, more massive stars can- not sustain magnetic fields in the same way. Yet some massive stars are indeed magnetic. Astronomers had suspected for some time that massive stars could acquire magnetic fields when two stars merge. But this is the first time researchers find such direct evi- dence of this happening. In the case of HD 148937, the merger must have happened recently. “Magnet- ism in massive stars isn’t expected to last very long compared to the life- time of the star, so it seems we have observed this rare event very soon after it happened,” Frost adds. ESO’s Extremely Large Telescope (ELT), currently under construction in the Chilean Atacama Desert, will enable researchers to work out what happened in the system in more detail, and perhaps reveal even more surprises.     36 ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ ﺗﻈﻬـــــﺮ اﻟﻠ ﻮﺣــــــﺎت اﻟــــــﺜﻼث اﻷوﻟــــــﻰ ﺗﺼــــــﻮر اُ ــــــ ـﻠــــــ ﻟ ﺎً ﺧ ﺎﻟ ﻏــــــّ ﻣﺼــــــ اﻟﻨﻈــــــﺎم اﻟﻨ ﻤــــــﻲ ــــــﻒ اﻟــــــﺬ ﺤﺪث اﻟﻌﻨ HD 148937 ــــﺔ ﻓـــــﻲ اﻟﻠﻮﺣــــﺔ اﻷﺧـــــ ة ــــﺔ ﺣﻘ ﻘ ؛ ﺗﻈﻬــــﺮﺻـــــﻮرة ﻓﻠﻜ . ـــــﺎن اﻟﻨﻈــــﺎم ﻳﺤﺘـــــﻮي ﻓــــﻲ اﻷﺻــــﻞ ﻋﻠــــــــﻰ ﺛﻼﺛــــــــﺔ ﻧﺠــــــــﻮم ﻋﻠــــــــﻰ اﻷﻗــــــــﻞ ) ــــــــﺔ اﻟ ﺴــــــــﺮى اﻟﻠﻮﺣــــــــﺔ اﻟﻌﻠﻮ ( ــــــــﺎن ﻣــــــــﻦ ﻌﻀــــــــﻬﻤﺎ ، اﺛﻨــــــــﺎن ﻣــــــــﻨﻬﻢ ﻗﺮ ذات ﻳــــــــﻮ اﻟــــــــ ﻌﺾوآﺧــــــــﺮ أ ﻌــــــــﺪ ﻜﺜــــــــ ﺣــــــــ م اﺻــــــــﻄﺪم اﻟﻨ ﻤــــــــﺎن اﻟــــــــﺪاﺧﻠ ﺎن واﻧــــــــﺪﻣﺠﺎ ) اﻟﻠﻮﺣــــــــﺔ اﻟ ﻤــــــــ ـــــــﺔ اﻟﻌﻠﻮ ( ﺧﻠـــــــﻖ ﻫــــــــﺬا اﻟـــــــ ـ ــــــــﻒ ﻧ ﻤـــــــﺎً ﺤﺪث اﻟﻌﻨ ــــــــﺪاً ﺟﺪ أﻛـــــــ وﻣﻐﻨﺎﻃ ﺴــــــــ ﺎً وﻫـــــــﻮ اﻵن ﻓــــــــﻲ ﺛﻨـــــــﺎﺋﻲ ﻣــــــــﻊ اﻟـــــﻨ ﻢ اﻷ ﻌـــــﺪ ) اﻟﻠﻮﺣـــــﺔ اﻟﺴـــــﻔﻠ ﺔ اﻟ ﺴـــــﺮى ( ﺧﻠﻘـــــﺖ اﻻﻧـــــﺪﻣﺎج أ ﻀـــــﺎ إﻟـــــﻰ إﻃـــــﻼق اﻟﻤـــــﻮاد اﻟـــــ ﻤـــــﺎ أد ﻳﺤ ﻂ ﺎﻟﻨﺠﻮم اﻵن اﻟﺴﺪ ﻢ اﻟﺬ ) اﻟﻠﻮﺣﺔ ا اﻟﺴﻔﻠ ﺔ ﻟ ﻤ .( ] ESO/L. Calçada, VPHAS+ team. Acknowledgement: CASU [ اﻧﺪﻣﺞ " اﻟﻨﺠﻤﺎن اﻟﺪاﺧﻠﻴﺎن ﺑﻄﺮﻳﻘﺔ ﻋﻨﻴﻔﺔ ﻣﻤﺎ أدى إﱃ ﺗﻜﻮ ﻳﻦ ﻧﺠﻢ ﻣﻐﻨﺎﻃﻴﴘ وﻗـﺬف ﺑﻌﺾ ا ـﻮاد ﻣﻤـﺎ أدى إﱃ ﺗﻜـﻮﻳﻦ اﻟﺴـﺪﻳﻢ وﺷﻜﻞ اﻟﻨﺠﻢ اﻷﺑﻌﺪ ﻣﺪار اً اً ﺟﺪﻳﺪ ﻣﻊ اﻟـﻨﺠﻢ ا ﻨ ــﺪﻣﺞ ﺣ ــﺪﻳﺜ ﺎً واﻟ ــﺬي أﺻ ــﺒﺢ اﻵن ﻣﻐﻨﺎﻃﻴﺴﻴ ﺎً ﻣﻤﺎ أدى إﱃ إﻧﺸﺎء اﻟﺜﻨﺎﺋﻲ اﻟﺬ ي ﻧﺮاه اﻟﻴﻮم ﰲ ﻣﺮﻛﺰ اﻟﺴﺪﻳﻢ . ﻳﻀﻴﻒ ا ﺆﻟﻒ ا ﺸﺎرك ﻟﻮران ﻣـﺎﻫﻲ وﻫـﻮ ﺣﺎﻟﻴ ﺎ أﺣﺪ ﻛﺒﺎر اﻟﺒﺎﺣﺜ ﰲ ا ﺮﺻـﺪ ا ﻠﻜـﻲ اﻟﺒﻠﺠﻴﻜﻲ " : ﻛﺎن ﺳﻴﻨﺎرﻳﻮ اﻻﻧﺪﻣﺎج ﻳﺪور ﰲ ذﻫﻨﻲ ﺑﺎﻟﻔﻌﻞ ﰲ ﻋـﺎم 2017 ﻋﻨـﺪﻣﺎ ﻗﻤـﺖ ﺑﺪراﺳﺔ أرﺻﺎد اﻟﺴﺪم اﻟﺘـﻲ ﺗـﻢ اﻟﺤﺼـﻮل ﻋﻠﻴﻬــﺎ ﺑﺎﺳــﺘﺨﺪام ﺗﻠﺴــﻜﻮب ﻫ ﺷــﻞ اﻟﻔﻀﺎﺋﻲ اﻟﺘﺎﺑﻊ ﻟﻮﻛﺎﻟﺔ اﻟﻔﻀﺎء اﻷوروﺑﻴﺔ ". إن اﻟﻌﺜﻮر ﻋﲆ ﺗﻨﺎﻗﺾ ﰲ اﻟﻌﻤﺮ ﺑ اﻟﻨﺠﻮم ﻳﺸـ إﱃ أن ﻫـﺬا اﻟﺴـﻴﻨﺎرﻳﻮ ﻫـﻮ اﻷﻛﺜـﺮ ﻣﻨﻄﻘﻴﺔ وﻟﻢ ﻳﻜﻦ ﻣﻦ ا ﻤﻜﻦ إﻇﻬﺎره إﻻ ﻣﻦ ﺧﻼل ﺑﻴﺎﻧﺎت ا ﺮﺻـﺪ اﻷوروﺑـﻲ اﻟﺠﻨـﻮﺑﻲ اﻟﺠﺪﻳﺪة . ﻳﴩح ﻫﺬا اﻟﺴﻴﻨﺎرﻳﻮ أﻳﻀ ﺎ ﺳﺒﺐ ﻛﻮن أﺣﺪ اﻟﻨﺠـﻮم ﰲ اﻟﻨﻈـﺎ م ﻣﻐﻨﺎﻃﻴﺴـﻴﺎ واﻵﺧﺮ ﻟﻴﺲ ﻛﺬﻟﻚ وﻫﻲ ﻣﻴﺰة ﻏﺮﻳﺒﺔ أﺧﺮى أﺧﺮى ﻟـ HD 148937 ﻟـــ HD 148937 رﺻــﺪت ﰲ ﺑﻴﺎﻧــﺎت ﺗﻠﺴـﻜﻮب ا ﺴـﺢ ) ( ﰲ إل ﺗ ـﻲ وﰲ اﻟﻮﻗ ـﺖ ﻧﻔﺴﻪ ﻳﺴﺎﻋﺪ ﰲ ﺣﻞ ﻟﻐﺰ ﻃﻮﻳﻞ اﻷﻣﺪ ﰲ ﻋﻠﻢ اﻟﻔﻠﻚ : ﻛﻴﻒ ﺗﺤﺼﻞ اﻟﻨﺠﻮم اﻟﻀـﺨﻤﺔ ﻋـﲆ ﻣﺠﺎﻻﺗﻬﺎ ا ﻐﻨﺎﻃﻴﺴﻴﺔ . ﰲ ﺣ أن ا ﺠـﺎﻻت ا ﻐﻨﺎﻃﻴﺴﻴﺔ ﻫﻲ ﺳـﻤﺔ ﻣﺸـﱰﻛﺔ ﻟﻠﻨﺠـﻮم ﻣﻨ ﺨﻔﻀﺔ اﻟﻜﺘﻠﺔ ﻣﺜ ﻞ ﺷﻤﺴﻨﺎ إﻻ أن اﻟﻨﺠﻮم اﻷﻛﺜﺮ ﺿـﺨﺎﻣﺔ ﻻ ﻳﻤﻜﻨﻬـﺎ اﻟﺤﻔـﺎظ ﻋـﲆ ا ﺠﺎﻻت ا ﻐﻨﺎﻃﻴﺴﻴﺔ ﺑﻨﻔﺲ اﻟﻄﺮﻳﻘﺔ . ﻣـﻊ ذﻟـﻚ ﻓـﺈن ﺑﻌـﺾ اﻟﻨﺠـﻮم اﻟﻀـﺨﻤﺔ ﻣﻐﻨﺎﻃﻴﺴﻴﺔ ﺑﺎﻟﻔﻌﻞ . ﻟﻘﺪ ﻛﺎن ﻋﻠﻤﺎء اﻟﻔﻠﻚ ﻳﺸﺘﺒﻬﻮن ﰲ أن اﻟﻨﺠﻮم اﻟﻀﺨﻤﺔ ﻳﻤﻜـﻦ أ ن ﺗﻜﺘﺴﺐ ﻣﺠﺎﻻت ﻣﻐﻨﺎﻃﻴﺴﻴﺔ ﻋﻨﺪﻣﺎ ﺗ ﻨﺪﻣﺞ ﻟﻜﻦ ﻫﺬه ﻫﻲ ا ﺮة اﻷوﱃ اﻟﺘـﻲ ﻳﺠـﺪ ﻓﻴﻬـﺎ اﻟﺒﺎﺣﺜﻮن ﻣﺜـﻞ ﻫـ ﺬا اﻟـﺪﻟﻴﻞ ا ﺒـﺎﴍ ﻋـﲆ ﺣﺪوث ذﻟﻚ ، و ﰲ ﺣﺎﻟـﺔ HD 148937 ﻳﺠـﺐ أ ن ﻳﻜﻮن اﻻﻧﺪﻣﺎج ﻗﺪ ﺣﺪث ﻣﺆﺧﺮا . ﻳﻀـﻴﻒ ﻓﺮوﺳـﺖ " : ﻻ ﻳﺘﻮﻗـﻊ أن ﺗﺴــﺘﻤﺮ ا ﻐﻨ ﺎﻃﻴﺴﻴﺔ ﰲ اﻟﻨﺠﻮم اﻟﻀﺨﻤﺔ ﺪة ﻃﻮﻳﻠﺔ ﻣﻘﺎرﻧﺔ ﺑﻌﻤﺮ اﻟﻨﺠﻢ ﻟﺬﻟﻚ ﻳﺒﺪو أﻧﻨﺎ رﺻـﺪﻧﺎ ﻫﺬا اﻟﺤﺪث اﻟﻨ ﺎدر ﺑﻌﺪ وﻗﺖ ﻗﺼ ﺟﺪا ﻣـﻦ ﺣﺪوﺛﻪ وﺳﻴﻤﻜﻦ اﻟﺘﻠﺴﻜﻮب اﻟﻜﺒ ﻟﻠﻐﺎﻳـﺔ ﻳﺘﻢ واﻟﺬي إﻧﺸﺎؤه ﺣ ﺎﻟﻴﺎ ﰲ ﺻﺤﺮاء أﺗﺎﻛﺎﻣـﺎ اﻟﺘﺸﻴﻠﻴﺔ اﻟﺒﺎﺣﺜ ﻣﻦ ﻣﻌﺮﻓﺔ ﻣـﺎ ﺣـﺪث ﰲ اﻟﻨﻈﺎم ﺑﻤﺰﻳﺪ ﻣﻦ اﻟﺘﻔﺼﻴﻞ، ور ﺑﻤﺎ ﻳ ﻜﺸـﻒ ﻋﻦ ا ﺰﻳﺪ ﻣﻦ ا ﻔﺎﺟﺂت . - ﻳﻮﻟﻴﻮ ﺃﻏﺴﻄﺲ 2 0 2 4