Free Astronomy Magazine July-August 2024 ARABIC VERSION

S The most detailed view ever of the expanding Universe by NOIRLab − Josie Fenske ince beginning its survey of the sky in 2021 the Dark Energy Spectroscopic Instrument (DESI) has observed a new set of 5000 galaxies every 20 minutes, totalling more than 100,000 galaxies per night, in its quest to create the largest 3D map of the Universe ever. Using the survey’s first-year data, which contains the largest extra- galactic spectroscopic sample ever collected, astronomers report that they have measured the Universe’s expansion history over the last 11 billion years with a precision better than 1%. These measurements con- firm the basics of our best model of ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 26 اﻟﺼﻮرة اﻷﻛ ﺗﻔﺼ ﻼً ﻟﺘﻮﺳﻊ ا ﻟ ﻮن ﻋﻠﻰاﻹﻃﻼق - ﻳﻮﻟﻴﻮ ﺃﻏﺴﻄﺲ 2 0 2 4 ﻗﺎﻣﺖ أداة اﻟﺘﺤﻠﻴﻞ اﻟﻄ ﻔﻲ ﻟﻠﻄﺎﻗـﺔ اﻟﻤﻈﻠﻤـﺔ ) DESI ( ـﺔ اﻷ ﻌـﺎد ﻟ ﻮﻧﻨـﺎ ﺣـ ﺑﺮﺳـﻢ أﻛـ ﺧﺮﻄـﺔ ﺛﻼﺛ اﻵن . ﺗــﻢ ﺗﻌﻴ ﻨﻬـﺎ ﻓــﻲ اﻟﺴــﻨﺔ اﻷوﻟــﻰ ﻣــﻦ ﺗُﻈﻬــﺮﻫــﺬﻩ اﻟﺸــﺮ ﺤﺔ اﻟﻤﺠــﺮات اﻟــ اﻟ ﺴــﺘﻐﺮق ﻤﺴــﺢ اﻟــﺬ ﻤـــﺲﺳـــﻨﻮات . ﺗﻘـــﻊ اﻷرضﻓـــﻲوﺳـــﻂﻫـــﺬﻩ اﻟﺸـــﺮ ﺤﺔ اﻟﺮﻓ ﻌـــﺔ ﻣـــﻦ اﻟـــ ـ ﺨﺮﻄﺔ اﻟ ﺎﻣﻠـــﺔ . ﻓـــﻲ اﻟﻘﺴـــﻢ اﻟﻤﻜ ﻣﻦ اﻟﺴﻬﻞ رؤ ﺔ اﻟ ﻨ ﺔ اﻷﺳﺎﺳ ﺔ ﻟﻠﻤﺎدة ﻓﻲ ﻮ ﻧﻨﺎ . : ﻘﻠﻢ ﺟﻮزيﻓ ﻨﺴﻜﻲ – ﻣﺨﺘ ﻧﻮﻳﺮﻻب ﻣﻨﺬ أن ﺑﺪأت ﻣﺴﺤﻬﺎ ﻟﻠﺴـﻤﺎء ﻋـﺎم 2021 ﻗﺎﻣﺖ أداة اﻟﺘﺤﻠﻴﻞ اﻟﻄﻴﻔﻲ ﻟﻠﻄﺎﻗﺔ ا ﻈﻠ ﻤﺔ ) DESI ( ﺑﺮﺻﺪ ﻣﺠﻤﻮﻋﺔ ﺟﺪﻳﺪة ﻣﻜﻮﻧﺔ ﻣﻦ 5000 ﻣﺠﺮة ﻛﻞ 20 دﻗﻴﻘﺔ ﺑﺈﺟﻤـﺎﱄ أﻛﺜـﺮ ﻣﻦ 100,000 ﻣﺠﺮة ﰲ اﻟﻠﻴﻠﺔ اﻟﻮاﺣﺪة وذﻟﻚ ﰲ ﺳﻌﻴﻬﺎ ﻹﻧﺸﺎء أﻛﱪ ﺧﺮﻳﻄﺔ ﺛﻼﺛﻴﺔ اﻷﺑﻌﺎد ﻟﻠﻜﻮن ﻋـﲆ اﻹﻃـﻼق . ﺑﺎﺳـﺘﺨﺪام ﺑﻴﺎﻧـﺎت اﻟﺴﻨﺔ اﻷوﱃ ﻟﻠﻤﺴﺢ، واﻟﺘﻲ ﺗﺤﺘﻮي ﻋﲆ أﻛﱪ ﻋﻴﻨﺔ ﻃﻴﻔﻴﺔ ﻣﻦ ﺧ ﺎرج ا ﺠﺮ ة ﺗـﻢ ﺟﻤﻌﻬـﺎ ﻋﲆ اﻹﻃﻼق أﻓﺎد ﻋﻠﻤﺎء اﻟﻔﻠﻚ أﻧﻬـﻢ ﻗـﺎﻣﻮا ﺑﻘﻴﺎس ﺗﺎرﻳﺦ ﺗﻮﺳﻊ اﻟﻜﻮن ﻋﲆ ﻣـﺪار اﻟــ 11 ﻣﻠﻴﺎر ﺳﻨﺔ ا ﺎﺿﻴﺔ ﺑﺪﻗﺔ أﻓﻀﻞ ﻣـﻦ 1 ٪ وﺗ ﺆﻛﺪ ﻫﺬه اﻟﻘﻴﺎﺳـﺎت أﺳﺎﺳـﻴﺎت أﻓﻀـﻞ ﻧﻤﻮذج ﻟﺪﻳﻨﺎ ﻟﻠﻜﻮن .