Free Astronomy Magazine November-December 2023 ARABIC VERSION

that spectrum is identical to a sam- ple of that same molecule here on Earth because electrons, protons, and neutrons all share the same fundamental properties and com- bine to form molecules in the same fundamental ways. When that same spectrum is obtained from a mole- cule in a distant galaxy, the only dif- ference we find is the redshifting of that spectrum due to the expansion of space itself. When that redshift is accounted for in the spectrum, that ancient molecule “way over there” is identical in all ways to that same molecule here on Earth. We take this as one of the many signs that the physics and chemistry of the early and distant universe, based on fundamental constants like the charge of the electron, Planck’s con- stant, and the speed of light itself, are not different in a detectable way from the same physics and chemistry that drives everything here on Earth today. The detection of PAHs in SPT0418- 47 by Prof. Joaquin Vieira and Kedar Phadke of the University of Illinois Urbana-Champaign and an international team of collaborators were interesting for three signifi- cant reasons. First, they were de- tectable at all at 12.3 billion light years and, thanks to the high-qual- ity and well-investigated diagnostic fingerprints of these molecules here on present-day Earth, their assign- ment was only complicated by the many different molecular structures that make up this branch of the or- ganic family tree. The second rea- son has less to do with organic chemistry and more to do with as- trophysics – there is an established connection between star formation and the presence of PAHs. These large aromatic molecules absorb strongly in the UV and radiate in the infrared, so much so that 20% of the infrared light we detect from star forming regions are attributa- ble to PAH emissions. Some modern perspectives even directly link the presence of PAHs with stellar forma- tion – a hypothesis that is chal- lenged with these SPT0418-47 measurements by the confirmed ab- sence of PAHs in some of the ob- served star-forming regions. The NOVEMBER-DECEMBER 2023 ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 12 ﻫﺬا اﻟﻄﻴﻒ ﻣﻄﺎﺑﻖ ﻟﻌﻴﻨﺔ ﻣﻦ ﻧﻔﺲ اﻟﺠﺰيء ﻫﻨ ـــﺎ ﻋ ـــﲆ اﻷرضﻷن اﻹﻟﻜﱰوﻧ ـــﺎت واﻟﱪوﺗﻮﻧﺎت واﻟﻨﻴﻮﺗﺮوﻧﺎت ﺟﻤﻴﻌﻬﺎ ﺗﺸﱰك ﰲ ﻧﻔ ـﺲ اﻟﺨﺼـﺎﺋﺺ اﻷﺳﺎﺳـﻴﺔ وﺗﺘﺤ ـﺪ ﻟﺘﺸﻜﻞ اﻟﺠﺰﻳﺌﺎت ﺑﻨﻔﺲ اﻟﻄﺮق اﻷﺳﺎﺳﻴﺔ . وﻋﻨﺪﻣﺎ ﻳﺘﻢ اﻟﺤﺼﻮل ﻋﲆ ﻧﻔﺲ اﻟﻄﻴﻒ ﻣﻦ ﺟﺰيء ﰲ ﻣﺠﺮة ﺑﻌﻴﺪة ﻓﺈن اﻻﺧﺘﻼف اﻟﻮﺣﻴﺪ اﻟﺬي ﻧﺠﺪه ﻫﻮ اﻻﻧﺰﻳﺎح اﻷﺣﻤﺮ ﻟﺬﻟﻚ اﻟﻄﻴﻒ ﺑﺴﺒﺐ ﺗﻮﺳﻊ اﻟﻔﻀﺎء ﻧﻔﺴﻪ . ﻋﻨﺪﻣﺎ ﻳﺘﻢ ﺣﺴ ﺎب ﻫﺬا اﻻﻧﺰﻳـﺎح اﻷﺣﻤـﺮ ﰲ اﻟﻄﻴﻒ ﻓﺈن ﻫﺬا ا ﻟﺠﺰيء اﻟﻘـﺪﻳﻢ " ﻫﻨـﺎك " ﻣﻄﺎﺑﻖ ﰲ ﺟﻤﻴﻊ اﻟﻨﻮاﺣﻲ ﻟـﻨﻔﺲ اﻟﺠـﺰيء ﻫﻨﺎ ﻋﲆ اﻷرض . ﻧﺤﻦ ﻧﻌﺘﱪ ﻫﺬا واﺣﺪ اً ﻣﻦ اﻟﻌﻼﻣﺎت اﻟﻌﺪﻳﺪة اﻟﺘﻲ ﺗﺸ إﱃ أن ﻓﻴﺰﻳـ ﺎء وﻛﻴﻤﻴـﺎء اﻟﻜـﻮن ا ﺒﻜﺮ واﻟﺒﻌﻴﺪ ا ﺒﻨﻴﺔ ﻋﲆ ﺛﻮاﺑـﺖ أﺳﺎﺳـﻴﺔ ﻣﺜﻞ ﺷﺤﻨﺔ اﻹﻟﻜﱰون وﺛﺎﺑﺖ ﺑﻼﻧﻚ وﴎﻋﺔ اﻟﻀﻮء ﻧﻔﺴﻬﺎ ﻻ ﺗﺨﺘﻠـ ﻒ ﺑﻄﺮﻳﻘـﺔ ﻳﻤ ﻜـﻦ اﻛﺘﺸـﺎﻓﻬﺎ ﻋـﻦ اﻟﻜـﻮن ، ﻧﻔـﺲ اﻟﻔﻴﺰﻳـﺎء واﻟﻜﻴﻤﻴﺎء اﻟﺘﻲ ﺗﺤﺮك ﻛـﻞ ﳾء ﻫﻨـﺎ ﻋـﲆ اﻷرض اﻟﻴﻮم . ﻛـﺎن اﻛﺘﺸـﺎف اﻟ ﻬﻴ ـﺪروﻛﺮﺑﻮن اﻟ ﻌﻄ ـﺮي ﻣﺘﻌﺪد اﻟﺤﻠﻘـﺎت ﰲ ا ﺠـﺮة SPT0418-47 ﺑﻮاﺳﻄﺔ اﻟﱪوﻓﻴﺴﻮر ﺟﻮاﻛ ﻓﻴ ا وﻛﻴﺪار ﻓﺎدﻛﻲ ﻣﻦ ﺟﺎﻣﻌﺔ إﻟﻴﻨﻮي أورﺑﺎﻧﺎ ﺷـﺎﻣﺒ وﻓﺮﻳﻖ دوﱄ ﻣﻦ ا ﺘﻌﺎوﻧ ﻣﺜـ ﻟﻼ اً ﻫﺘﻤـﺎم ﻟﺜﻼﺛﺔ أﺳﺒﺎب ﻣﻬﻤﺔ : أوﻻً ﻛﺎن ﻣﻦ ا ﻤﻜـﻦ اﻛﺘﺸـﺎﻓﻬﺎ ﻋـﲆ ﺑﻌـﺪ 12.3 ﻣﻠﻴﺎر ﺳﻨﺔ ﺿﻮﺋﻴﺔ وﺑﻔﻀﻞ اﻟﺒﺼﻤﺎت اﻟﺘﺸﺨ ﻴﺼﻴﺔ ﻋﺎﻟﻴﺔ اﻟﺠﻮدة وا ﺪروﺳﺔ ﺟﻴﺪ اً ﻟﻬﺬه اﻟﺠﺰﻳﺌﺎت ﻫﻨـﺎ ﻋـ ﲆ اﻷرض اﻟﺤﺎﻟﻴـﺔ ﻛﺎﻧﺖ ﻣﻬﻤﺘﻬﺎ ﻣﻌﻘﺪة ﻓﻘﻂ ﺑﺴـﺒﺐ اﻟﻌﺪﻳـﺪ ﻣﻦ اﻟﻬﻴﺎﻛ ﻞ اﻟﺠﺰﻳﺌﻴﺔ ا ﺨﺘﻠﻔﺔ اﻟﺘﻲ ﺗﺸﻜﻠﻬﺎ ا ا ﻫﺬ ﻟﻔﺮع ﻣﻦ ﺷـﺠﺮة اﻟﻌﺎﺋﻠـﺔ اﻟﻌﻀـﻮﻳﺔ اﻟﺴﺒﺐ اﻟﺜﺎﻧﻲ ﻟـﻴﺲ ﻟـﻪ ﻋﻼﻗـﺔ ﺑﺎﻟﻜﻴﻤﻴـﺎء اﻟﻌﻀﻮﻳﺔ ﺑﻘﺪر ﻣﺎ ﻳﺘﻌﻠﻖ ﺑﺎﻟﻔﻴﺰﻳﺎء اﻟﻔﻠﻜﻴﺔ ﻓﻬﻨﺎك ﻋﻼﻗﺔ ﺛﺎﺑﺘـﺔ ﺑـ ﺗﻜـﻮﻳﻦ اﻟﻨﺠـﻮم ووﺟﻮد اﻟﻬﻴﺪروﻛﺮﺑﻮﻧﺎت اﻟﻌﻄﺮﻳﺔ ﻣﺘﻌـﺪدة اﻟﺤﻠﻘﺎت ﺗﻤﺘﺺ ﻫﺬه اﻟﺠﺰﻳﺌـﺎت اﻟﻌﻄﺮﻳـﺔ اﻟﻜﺒ ة ﺑﻘـﻮة اﻷﺷـﻌﺔ ﻓـﻮق اﻟﺒﻨﻔ ﺴـﺠﻴﺔ وﺗﺸﻊ ﰲ اﻷ ﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤـﺮاء ﻟﺪرﺟـﺔ أن 20 % ﻣﻦ ﺿﻮء اﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤﺮاء اﻟﺬي ﻧﻜﺘﺸﻔﻪ ﻣﻦ ﻣﻨﺎﻃﻖ ﺗﺸﻜﻞ اﻟﻨﺠﻮم ﻳﻌـﺰى إﱃ اﻧﺒﻌﺎﺛ ـﺎت اﻟﻬﻴــﺪروﻛﺮﺑﻮﻧﺎت اﻟﻌﻄﺮﻳــﺔ ﻣﺘﻌﺪدة اﻟﺤﻠﻘﺎت ﺣﺘﻰ أن ﺑﻌـﺾ وﺟﻬـﺎت ﻣﺘﻌﺪدة اﻟﺤﻠ ﻘﺎت ﺣﺘﻰ أن ﺑﻌـﺾ وﺟﻬـﺎت اﻟﻨﻈﺮ اﻟﺤﺪﻳﺜﺔ ﺗـﺮﺑﻂ ﺑﺸـﻜﻞ ﻣﺒـﺎﴍ ﺑـ وﺟﻮد اﻟﻬﻴﺪروﻛﺮﺑﻮﻧﺎت اﻟﻌﻄﺮﻳـﺔ ﻣﺘﻌـﺪدة اﻟﺤﻠﻘﺎت وﺗﻜﻮﻳﻦ اﻟﻨﺠﻮم وﻫﻲ ﻓﺮﺿﻴﺔ ﺗـﻢ ﺗﺤﺪﻳﻬﺎ ﻣﻦ ﺧﻼل ﻗﻴﺎﺳﺎت ـ ﺗﺤــﺪﻳﻬﺎ ﻣــﻦ ﺧــﻼل ﻗﻴﺎﺳــﺎت ا ﺠــﺮة SPT0418-47 و اﻟﻐﻴــــــﺎب ا ﺆﻛــــــﺪ ﻟﻠﻬﻴﺪروﻛﺮﺑﻮﻧﺎت اﻟﻌﻄﺮﻳﺔ ﻣﺘﻌﺪدة اﻟﺤﻠﻘﺎت ﰲ ﺑﻌﺾ ﻣﻨﺎﻃﻖ ﺗﺸﻜﻞ اﻟﻨﺠﻮم ا ﺮﺻﻮدة . ﻧﻮﻓﻤﺒﺮ - ﺩﻳﺴﻤﺒﺮ 2 0 2 3 ــــﻮن ﺘﻮﺳــــﻊوﻫــــﺬا اﻟﺘﻮﺳــــﻊ ﻤﺘــــﺪ اﻟﻀــــﻮء اﻟﻤﺴـــــﺎﻓﺮﻋــــ اﻟﻔﻀـــــﺎء ﻓــــﻲﻇـــــﺎﻫﺮة ﺗﻌــــﺮف ﺎﺳـــــﻢ اﻟ ــــﻮﻧﻲ اﻻﻧﺰ ــــﺎح اﻷ ﻤــــﺮاﻟ . ﻘﻄﻌﻬــــﺎ اﻟﻀــــﻮء ﻠﻤــــﺎ زاد اﻻﻧﺰ ــــﺎح ﻧﺤــــﻮ اﻷ ﻤــــﺮزادتاﻟﻤﺴــــﺎﻓﺔ اﻟــــ وﻧﺘﻴﺠـﺔ ﻟـﺬﻟﻚ ﻓـﺈنﻫﻨـﺎك ــﺔ ﺣﺎﺟـﺔ إﻟـﻰﺗﻠﺴـ ﻮ ﺎتﻣــﺰودة ﺑ ﺎﺷـﻔﺎتﻟﻸﺷـﻌﺔ ﺗﺤـﺖاﻟــ ﻤﺮاء ﻟﺮؤ اﻟﻀﻮء اﻟﺼﺎدرﻣﻦ اﻟﻤﺠﺮات اﻷوﻟﻰواﻷﻛ ﻌﺪاً .