Free Astronomy Magazine May-June 2023 ARABIC VERSION

MAY-JUNE 2023 The team is studying a diverse sam- ple of 19 spiral galaxies, and in Webb’s first few months of science operations, observations of five of those targets – M74, NGC 7496, IC 5332, NGC 1365, and NGC 1433 – have taken place. The results are al- ready astounding astronomers. “The clarity with which we are seeing the fine structure certainly caught us by surprise,” said team member David Thilker of Johns Hopkins University in Baltimore, Maryland. “We are directly seeing how the en- ergy from the formation of young stars affects the gas around them, and it’s just remarkable,” said team member Erik Rosolowsky of the University of Alberta, Canada. The images from Webb’s Mid-In- frared Instrument (MIRI) reveal the presence of a network of highly structured features within these galaxies – glowing cavities of dust and huge cavernous bubbles of gas that line the spiral arms. In some re- gions of the nearby galaxies ob- served, this web of features appears built from both individual and over- lapping shells and bubbles where young stars are releasing energy. “Areas which are completely dark in Hubble imaging light up in exquisite detail in these new infrared images, allowing us to study how the dust in the interstellar medium has ab- sorbed the light from forming stars and emitted it back out in the in- frared, illuminating an intricate net- work of gas and dust,” said team member Karin Sandstrom of the ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ ٣٨ ﻳﺪرس اﻟﻔﺮﻳﻖ ﻋﻴﻨﺔ ﻣﺘﻨﻮﻋﺔ ﻣﻦ ١٩ ﻣﺠـﺮة ﺣﻠﺰوﻧﻴـﺔ ، وﰲ اﻷﺷـﻬﺮ اﻟﻘﻠﻴﻠ ـﺔ اﻷوﱃ ﻣـﻦ اﻟﻌﻤﻠﻴﺎت اﻟﻌﻠﻤﻴﺔ ﻟﺘﻠﺴﻜﻮب وﻳﺐ ﺗـﻢ رﺻـﺪ ـــــ ﺧﻤﺴـﺔ ﻣـﻦ ﻫـﺬه اﻷﻫـﺪاف M74 و NGC 7496 و IC 5332 و NGC 1365 و NGC 1433 . اﻟﻨﺘﺎﺋﺞ ﺟﺎﻫﺰة ﺑﺎﻟﻜﺎﻣﻞ ﻋﻠﻤﺎء اﻟﻔﻠﻚ . ﻟﻮنﻮ ﻣﺬﻫ ﻗﺎل ﻋﻀﻮ اﻟﻔﺮﻳﻖ دﻳﻔﻴـﺪ ﺛﻴﻠﻜـﺮ ﻣﻦ ﺟﺎﻣﻌﺔ ﺟﻮﻧﺰ ﻫﻮﺑﻜﻨﺰ ﰲ ﺑﺎﻟﺘﻴﻤﻮر ﺑﻮﻻﻳﺔ : " ﻣﺎرﻳﻼﻧﺪ اﻟﻮﺿﻮح اﻟﺬي ﻧﺸﻬﺪ ﺑـﻪ اﻟﻬﻴﻜـﻞ اﻟﺪﻗﻴﻖ ﻓﺎﺟﺄﻧﺎ ﺑﺎﻟﺘﺄﻛﻴﺪ ." ﻗﺎل ﻋﻀﻮ اﻟﻔﺮﻳـﻖ إرﻳﻚ روﺳﻮﻟﻮﻓﺴﻜﻲ ﻣﻦ ﺟﺎﻣﻌﺔ أﻟﱪﺗﺎ ﺑﻜﻨﺪا : " ﻧﺤﻦ ﻧﺮى ﺑﺸﻜﻞ ﻣﺒﺎﴍﻛﻴﻒ ﺗﺆﺛﺮ اﻟﻄﺎﻗـﺔ اﻟﻨﺎﺗﺠﺔ ﻋﻦ ﺗﻜﻮﻳﻦ اﻟﻨﺠﻮم اﻟﺸﺎﺑﺔ ﻋﲆ اﻟﻐﺎز ا ﺤﻴﻂ ﺑﻬﺎ ، وﻫﺬا أﻣﺮ راﺋﻊ ." ﺗﻜﺸﻒ اﻟﺼﻮر ا ـﺄﺧﻮذة ﺑﻜـﺎﻣ ا اﻷﺷـﻌﺔ ﺗﺤـﺖ اﻟﺤﻤـﺮاء ا ﺘﻮﺳﻄﺔ ) (MIRI ﻋـﻦ وﺟـﻮد ﺷـﺒﻜﺔ ﻣـﻦ ا ﻴﺰات ﺷﺪﻳﺪة اﻟﺘﻨﻈﻴﻢ داﺧﻞ ﻫـﺬه ا ﺠـﺮات ـــ ﺗﺠﺎوﻳﻒ ﻣﺘﻮﻫﺠﺔ ﻣـﻦ اﻟﻐﺒـﺎر واﻟﻔﻘﺎﻋـﺎت اﻟﻜﻬﻔﻴﺔ اﻟﻀﺨﻤﺔ ﻣـﻦ اﻟﻐـﺎز اﻟﺘـﻲ ﺗـﺒﻄﻦ اﻷذرع اﻟﺤﻠﺰوﻧﻴﺔ . ﰲ ﺑﻌﺾ ﻣﻨﺎﻃﻖ ا ﺠـﺮات اﻟﻘﺮﻳﺒﺔ اﻟﺘﻲ ﻟﻮﺣﻈﺖ ، ﺗﻈﻬﺮ ﺷﺒﻜﺔ ا ﻴﺰات ﻫﺬه ﻣﺒﻨﻴﺔ ﻣﻦ ﻛﻞ ﻣﻦ اﻷﺻﺪاف واﻟﻔﻘﺎﻋﺎت اﻟﻔﺮدﻳـﺔ وا ﺘﺪاﺧﻠـﺔ ﺣﻴـﺚ ﺗﻄﻠـﻖ اﻟﻨﺠـﻮم اﻟﻴﺎﻓﻌﺔ اﻟﻄﺎﻗﺔ . ﺗﴤء ا ﻨﺎﻃﻖ ا ﻈﻠﻤﺔ ﺗﻤﺎﻣًﺎ ﰲ ﺗﺼﻮﻳﺮ ﻫﺎﺑﻞ ﺑﺘﻔﺎﺻﻴﻞ راﺋﻌـﺔ ﰲ ﻫـﺬه اﻟﺼـﻮر ا ﻟﺠﺪﻳـﺪة ﺑﺎﻷﺷﻌﺔ ﺗﺤـﺖ اﻟﺤﻤـﺮاء ﻣﻤـﺎ ﻳﺴـﻤﺢ ﻟﻨـﺎ ﺑﺪراﺳﺔ ﻛﻴﻔﻴﺔ اﻣﺘﺼﺎص اﻟﻐﺒـﺎر ﰲ اﻟﻮﺳـﻂ اﻟﻨﺠﻤﻲ ﻟﻠﻀﻮء ﻣﻦ ﺗﻜﻮﻳﻦ اﻟﻨﺠﻮم وإﺻﺪاره ﻣﺮة أﺧﺮى ﰲ اﻷﺷـﻌﺔ ﺗﺤـﺖ اﻟﺤﻤـﺮاء ﻣﻤـﺎ ﻳﴤء ﺷـﺒﻜﺔ ﻣﻌﻘـﺪة ﻣـﻦ اﻟﻐـﺎز واﻟﻐﺒـﺎر ـ ﺘﻌﻘﻴﺪ وﻗﺎﻟﺖ ﻋﻀﻮ اﻟﻔﺮﻳﻖ ﻛﺎرﻳﻦ ﺗﻤﺘﻠــــﺊ اﻷذرع اﻟـــــ ـ ﺤﻠﺰوﻧ ﺔ ﻟــــــ NGC 7496 وﻫـــــــــــﻲو اﺣـــــــــــﺪة ﻣــــــــــــﻦ إ ﻤـــــــــــﺎﻟﻲ ١٩ ﻣﺠــــــــــــﺮة ﻣﺴﺘﻬﺪﻓﺔ ﻟ ﻠﺪراﺳﺔ ﻣﻦ ﻗﺒـﻞ ﺑﺮ ـﺎﻣﺞ ا ـﺎء ﻟﻔ ــــــﺔ ﻓــــــﻲ اﻟﻤﺠــــــﺮات ــــــﺔ اﻟﻌﺎﻟ ذات اﻟﺪﻗــــــﺔ اﻟﺰاو ـــــــــﺔ اﻟﻘﺮ (PHANGS) ﻔﻘﺎﻋـــــــــﺎت وأﺻـــــــــﺪاف ــــﺔ ﻣﺘﺪاﺧﻠــــﺔ ﻣــــﻊ ﻌﻀــــﻬﺎ اﻟــــ ﻌﺾﻓــــﻲ ﻬﻔ ﻫﺬﻩ اﻟﺼﻮرة ﻣﻦ و ﺐﻣﻨﺘﺼـﻒ اﻷﺷـﻌﺔ ﺗﺤـﺖ ا ﻤــــــــــــــﺮاء . أداة ) ﻣــــــــــــــ ي .( ﻫــــــــــــــﺬﻩ ا ﻴــــــــــــــﻮط واﻟﺘﺠــﺎو ﻒﻫـــﻲدﻟﻴـــﻞ ﻋﻠــﻰ إ ﻃـــﻼق اﻟﻨﺠـــﻮم ــــــــﺎﻻت ، اﻟﺸــــــــﺎ ﺔ ﻟﻠﻄﺎﻗــــــــﺔ ، وﻓــــــــﻲ ﻌــــــــﺾ ا ـــــﺎرﻣـــــﻦ اﻟﻮﺳـــــﻂ اﻟﻨ ﻤـــــﻲ ﺗﻨﻔـــــﺚ اﻟﻐـــــﺎزواﻟﻐ اﻟﻤﺤ ﻂ ﺑﻬﺎ . - ﻣﺎﻳﻮ ﻳﻮﻧﻴﻮ 2023