Free Astronomy Magazine May-June 2023 ARABIC VERSION

T The largest two-dimensional map of the sky by NOIRLab − Charles Blue he Universe is teeming with galaxies, each brimming with billions of stars. Though all galaxies shine brightly, many are cloaked in dust while others are so distant that to observers on Earth they appear as little more than faint smudges. By creating comprehensive maps of even the dimmest and most-distant galaxies, as- tronomers are better able to study the structure of the Universe and unravel the mysterious proper- ties of dark matter and dark energy. The largest such map to date has just grown even larger, with the tenth data release from the DOE’s Lawrence Berkeley National Laboratory’s Dark Energy Spec- troscopic Instrument (DESI) Legacy Imaging Survey. The DESI Legacy Imaging Survey expands on the data included in two earlier companion surveys: the Dark Energy Camera (DECam) Legacy Survey and the Beijing-Arizona Sky Survey. Jointly these three surveys imaged 14,000 square degrees of the sky visible from the northern hemisphere using tel- escopes at NSF’s NOIRLab’s Kitt Peak National Ob- servatory (KPNO) and Cerro Tololo Inter-American Observatory (CTIO) in Chile. This ambitious six-year effort involved three telescopes, one petabyte (1000 trillion bytes) of data, and 100 million CPU hours on one of the world’s most powerful com- puters at the US Department of Energy’s National Energy Research Scientific Computing Center. ﻛ أ ﺧﺮﻄﺔ ﺛﻨﺎﺋ ﺔ اﻷ ﻌﺎد ﻟﻠﺴﻤﺎء ﻋﻠﻰاﻹﻃﻼق ـــــــ ﻳﻌﺞ ﺑﺎ ﺠﺮات و ﻛﻞ ﻣﻨﻬﺎ ﻣﲇء ﺑﻤﻠﻴﺎرات اﻟﻨﺠـﻮم . ﻋﲆ اﻟﺮﻏﻢ ﻣ ﻦ أن ﺟﻤﻴﻊ ا ﺠﺮات ﺗﺘﺄﻟﻖ ﺑﺸﻜﻞ ﺳﺎﻃﻊ ، إﻻ أن اﻟﻌﺪﻳﺪ ﻣﻨﻬﺎ ﻣﻐﻄﻰ ﺑﺎﻟﻐﺒﺎر ﺑﻴﻨﻤﺎ اﻟﺒﻌﺾ اﻵﺧـﺮ ﺑﻌﻴـﺪ ﺟـﺪًا ﻟﺪرﺟﺔ أﻧ ﻟ ﻬﺎ ﺗﻈﻬﺮ ﻠﻤﺮاﻗﺒ ﻋﲆ اﻷرض ﺎ ﻋـﲆ أﻧﻬـ اوﺿـﺢ ﺑﻘﻠﻴﻞ ﻣﻦ ﻣﺠﺮد ﻟﻄﺨﺎت ﺧﺎﻓﺘﺔ . ﻣﻦ ﺧﻼل إﻧﺸـﺎء ﺧـﺮاﺋﻂ ﺷﺎﻣﻠﺔ ﻟﻠﻤﺠﺮات اﻷﻛﺜﺮ ﺧﻔﻮﺗًﺎ وﺑُﻌﺪًا ، ﻳﺼﺒﺢ ﻋﻠﻤﺎء اﻟﻔﻠـﻚ أﻛﺜﺮ ﻗﺪر ة ﻋﲆ دراﺳـﺔ ﺑﻨﻴـﺔ اﻟﻜـﻮن وﻛﺸـﻒ اﻟﺨﺼـﺎﺋﺺ اﻟﻐﺎﻣﻀﺔ ﻟﻠﻤﺎدة ا ﻈﻠﻤﺔ واﻟﻄﺎﻗﺔ ا ﻈﻠﻤﺔ ﻧﻤﺖ أﻛﱪ ﺧﺮﻳﻄﺔ ﻣﻦ ﻫﺬا اﻟﻨﻮع ﺣﺘﻰ اﻵن ﺑﺸﻜﻞ أﻛﱪ ﻣـﻊ اﻹﺻـﺪار اﻟﻌـﺎﴍ ﻟﻠﺒﻴﺎﻧﺎت ﻣﻦ ﻣﺨﺘﱪ ﻟﻮراﻧﺲ ﺑ ﻛﲇ اﻟﻮﻃﻨﻲ اﻟﺘـﺎﺑﻊ ﻟـﻮزارة اﻟﻄﺎﻗﺔ وﻫﻮ اداة اﻟﺘﺤﻠﻴﻞ اﻟﻄﻴﻔﻲ ﻟﻠﻄﺎﻗﺔ ا ﻈﻠﻤﺔ ) .(DESI ﻳﺘﻮﺳﻊ ﻣﺴ ﺢ اﻟﺘﺼﻮﻳﺮ ﻣـﻦ DESI ﰲ اﻟﺒﻴﺎﻧـﺎت ا ﻀـﻤﻨﺔ ﰲ ﻣﺴﺤ ﺳﺎﺑﻘ : ﻣﺴﺢ ﻟﻜﺎﻣ ا اﻟﻄﺎﻗﺔ ا ﻈﻠﻤﺔ (DECam) وﻣﺴﺢ ﺑﻜ - أرﻳﺰوﻧﺎ ﻟﻠﺴﻤﺎء ﺻـﻮرت ﻫـﺬه اﻻﺳـﺘﻄﻼﻋﺎت اﻟﺜﻼﺛﺔ ﻣﺠﺘﻤﻌﺔ ١٤,٠٠٠ درﺟﺔ ﻣﺮﺑﻌﺔ ﻣﻦ اﻟﺴـﻤﺎء ا ﺮﺋﻴـﺔ اﻟ ﻣﻦ ﻨﺼﻒ اﻟﺸﻤﺎﱄ ﻟﻸرض ﺑﺎﺳﺘﺨﺪام ﺗﻠﺴﻜﻮﺑﺎت ﰲ ﻣﺮﺻﺪ ﻛﺖ ﺑﻴﻚ اﻟﻮﻃﻨﻲ وﻣﺮﺻﺪ ﻛﺮو ﺗﻮﻟﻮﻟﻮ . ﰲ ﺗﺸﻴﲇ ﺗﻀﻤﻨﺖ ﻫﺬه اﻟﺠﻬﻮد اﻟﺘﻲ اﺳـﺘﻤﺮت ﺳـﺖ ﺳـﻨﻮات ﺛﻼﺛـﺔ ﺗﻠﺴﻜﻮﺑﺎت وواﺣﺪ ﺑﻴﺘﺎﺑﺎﻳـﺖ ) ١٠٠٠ ﺗﺮﻳﻠﻴـﻮن ﺑﺎﻳـﺖ ﻣـﻦ ( اﻟﺒﻴﺎﻧﺎت و ١٠٠ ﻣﻠﻴﻮن ﺳﺎﻋﺔ ﻣﻦ وﺣﺪة ا ﻌﺎﻟﺠﺔ ا ﺮﻛﺰﻳـﺔ ﻋﲆ أﺣﺪ أﻗﻮى أﺟﻬﺰة اﻟﻜﻤﺒﻴﻮﺗﺮ ﰲ اﻟﻌﺎﻟﻢ ﺑ ﻤﺮﻛﺰ اﻟﺤﻮﺳـﺒﺔ اﻟﻌﻠﻤﻴﺔ ﻷﺑﺤﺎث اﻟﻄﺎﻗﺔ اﻟﺘﺎﺑﻊ ﻟﻮزارة ا ﻟﻄﺎﻗﺔ اﻷﻣﺮﻳﻜﻴﺔ . : ﻘﻠﻢ ﺗﺸﺎرﻟﺰ ﻟﻮ - ) ﻣﺨﺘ ﻧﻮﻳﺮﻻب ( ﺻـــــــــــــــــﻮرة ﺗﺘﻤﺤـــــــــــــــــﻮرﺣـــــــــــــــــﻮل ـــــــــﺔ ﻣ ﻤﻮﻋـــــــــﺔ ﻣﺠـــــــــﺮات ﻗﺮ ﻧﺴــــــﺒ ًﺎ ﻄﻠــــــﻖ ﻋﻠﻴﻬــــــﺎ ) أﺑﻴــــــﻞ 3158 ( ـــــــــــــــــــــــــــــﺎن ﻟﻠﻀــــــــــــــــــــــــــــــﻮء اﻟﻤﻨ ﻌــــــــــــــــــﺚ ﻣـــــــــــــــــــﻦ ﻫـــــــــــــــــــﺬﻩ اﻟﻤﺠﺮات ﻗ ﻤﺔ اﻧﺰ ـﺎح أ ﻤـﺮ ﻗــﺪرﻫﺎ ٠.٠٥٩ أﻧـــﮫ ﻣﻤـــﺎ ﻌــ ﺳـــــــﺎﻓﺮﻣـــــــﺎ ﻘـــــــﺮ ﻣـــــــﻦ ٨٢٥ ﻣﻠﻴـــــــﻮنﺳـــــــﻨﺔ ﻓـــــــﻲ رﺣﻠﺘـــــــﮫ إﻟــــــﻰ اﻷرض . اﻟﺼــــــﻮرة ﺟـــــــ ﺰء ﺻـــــﻐ ﻣـــــﻦ اﺳـــــﺘﺒ ﺎﻧﺎت ﻣـــــﻦ ﺟﻬــــــــــﺎز اﻟﺘﺤﻠﻴــــــــــﻞ اﻟﻄ ﻔــــــــــﻲ ﻟﻠﻄﺎﻗــﺔ اﻟﻤﻈﻠﻤــﺔ DESI وﻫــــــﻮ ﻣﺴـــــــﺢ ﺿــــــ ﻢ ﻣﺪﺗـــــــﮫ ﺳــﺖﺳــﻨﻮات ﻐﻄــﻲ ﻧﺼــﻒ ًـــﺎ اﻟﺴــﻤﺎء ﺗﻘﺮ . ﺗـــﻢ اﻟﺘﻘـــﺎط ﻣﻌﻈـــــــﻢ اﻟﺒ ﺎﻧـــــــﺎت اﻟـــــــ ـ ﺨﺎﺻﺔ ﺎﻟﺼـــﻮرة ﻓــــﻲ اﻷﺻـــﻞ ﺠــــﺰء ﻣـﻦ ﻣﺴـﺢ [LoVoCCS/ DESI Legacy I aging Survey/KPNO/NOIR- Lab/NSF/AURA; Image processing: T.A. Rec- tor (University of Alaska Anchorage/ NSF’s NOIRLab, Jen Miller, M. Zamani LoVoCCS. - ﻣﺎﻳﻮ ﻳﻮﻧﻴﻮ 2023 اﻟ ﻮن