Free Astronomy Magazine July-August 2024 ARABIC VERSION

the Universe, while also uncovering some tantalizing areas to explore with more data. DESI is an international science col- laboration of more than 900 re- searchers from over 70 institutions around the world. DESI is managed by the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (LBNL) with primary funding from the Department’s Office of Science. The instrument is mounted on the U.S. National Science Foundation Nicholas U. Mayall 4-meter Tele- scope at Kitt Peak National Obser- vatory, a Program of NSF NOIRLab. To map the cosmos, DESI collects light from millions of galaxies across more than a third of the en- tire sky. By breaking down the light from each gal- axy into its spectrum of col- ors, DESI can determine how much the light has been redshifted, or stretched to a longer wavelength, by the expansion of the Universe during the billions of years it trav- eled before reaching Earth. In gen- eral, the higher the redshift the fur- ther away the galaxy is. Equipped with 5,000 tiny robotic ‘eyes,’ DESI is able to perform this measurement at an unprecedented rate. In its first year alone DESI sur- passed all previous surveys of its kind in terms of quantity and qual- ity. With incredible depth and pre- cision, DESI has brought new insight to one of the biggest mysteries in physics: dark en- ergy — the unknown ingre- dient c au s i ng the expansion of our Universe to accelerate. “The DESI instrument has transformed the Mayall Tele- scope into the world’s premier cosmic cartography machine,” says Pat McCarthy, Director of NOIRLab. “The DESI team has set a new stan- dard for studies of large-scale struc- ture in the Universe. These first-year data are only the beginning of DESI’s quest to unravel the expan- sion history of the Universe and they hint at the extraordinary sci- ence to come.” DESI’s first-year data have allowed astronomers to measure the expan- sion rate of the Universe out to 11 ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 27 4 أﻣﺘﺎر ﰲ ﻣﺮﺻﺪ ﻛﻴﺖ ﺑﻴـﻚ اﻟـﻮﻃﻨﻲ وﻫـﻮ ﺑﺮﻧﺎﻣﺞ ﺗﺎﺑﻊ ﺨﺘﱪ ﻧﻮﻳﺮﻻب اﻟﺘﺎﺑﻊ ﺆﺳﺴﺔ اﻟﻌﻠﻮم اﻟﻮﻃﻨﻴـﺔ . ﻟﺮﺳـﻢ ﺧﺮﻳﻄـﺔ ﻟﻠﻜـﻮن ﺗﺠﻤـﻊ أداة ) DESI ( اﻟﻀــﻮء ﻣـﻦ ﻣﻼﻳــ ا ﺠ ـﺮات ﻋ ـﱪ أﻛﺜــﺮ ﻣ ـﻦ ﺛﻠــﺚ اﻟﺴ ـﻤﺎء ﺑﺄﻛﻤﻠﻬﺎ . ﻣﻦ ﺧﻼل ﺗﺤﻠﻴﻞ اﻟﻀﻮء اﻟﻘﺎدم ﻣﻦ ﺠﺮة ـ ﻛﻞ ﻣ إﱃ ﻃﻴﻒ اﻷﻟـﻮان اﻟـﺨﺎص ﺑـﻬﺎ ـﻳﻤ ﻜﻦ ﻟـ DESI ﺤﺪﻳﺪ ـﺗ ﺪارـﻣﻘ ـاﻧ ﺰﻳﺎح اﻟﻀﻮء ﻧﺤﻮ اﻷﺣﻤﺮ أو ﺗﻤﺪده إﱃ ﻮلـﻃ ﻮﺟﻲ ـﻣ أﻃﻮ ل ﻦ ـﻣ ﻼلـﺧ ﻊـﻮﺳـﺗ اﻟﻜﻮن ﻣﺨﺘــﱪ ﻟـﻮراﻧﺲ ﺑـ ﻛﲇ اﻟـﻮﻃﻨﻲ اﻟﺘـﺎﺑﻊ ﻟﻮزارة اﻟﻄﺎﻗﺔ ا ﻷﻣﺮﻳﻜﻴﺔ ﺑﺘﻤﻮﻳـﻞ أوﱄ ﻣـﻦ ﻣﻜﺘﺐ اﻟﻌ ﻠﻮم اﻟﺘﺎﺑﻊ ﻟﻠـﻮزارة . ﺗـﻢ ﺗﺮﻛﻴـﺐ اﻷداة ﻋــﲆ ﺗﻠﺴــﻜﻮب ﻣﺆﺳﺴــﺔ اﻟﻌﻠــﻮم اﻟﻮﻃﻨﻴﺔ اﻷﻣﺮﻳﻜﻴﺔ ﻧﻴﻜﻮﻻس ﻳﻮ . ﻣﺎﻳﺎل اﻟﺬي ﻳﺒﻠﻎ ﻃﻮﻟﻪ ﻣﻊ اﻟﻜﺸﻒ أﻳﻀ ﺎً ﻋﻦ ﺑﻌﺾ ا ﻨﺎﻃﻖ ا ﺤ ة اﻟﺘﻲ ﻳﻤﻜﻦ اﺳﺘﻜﺸﺎﻓﻬﺎ ﺑﺎﺳـﺘﺨﺪام ا ﺰﻳـﺪ ﻣﻦ اﻟﺒﻴ ﺎﻧﺎت . ) ﻣﴩوع DESI ( ﻫﻮ ﺗﻌـﺎون ﻋﻠﻤﻲ دوﱄ ﻳﻀﻢ أﻛﺜﺮ ﻣﻦ 900 ﺑﺎﺣـﺚ ﻣـﻦ أﻛﺜﺮ ﻣﻦ 70 ﻣﺆﺳﺴﺔ ﺣﻮل اﻟﻌﺎﻟ .ﻢ ﺗﺘﻢ إدارة ا ﴩوع ﻣﻦ ﻗﺒﻞ ﻳﺒﻠﻎ ﻗﻄﺮة ﺧﻼل ﻣﻠﻴﺎرات اﻟﺴﻨ اﻟﺘﻲ ﺳﺎﻓﺮﻫﺎ ﻗﺒﻞ وﺻﻮﻟﻪ إﱃ اﻷرض . ﺑﺸﻜﻞ ﻋـﺎم ﻛﻠﻤـﺎ زاد اﻻﻧﺰﻳﺎح اﻷﺣﻤﺮ ﻛﻠﻤـﺎ اﺑﺘﻌـﺪت ا ﺠـﺮة . ﺑﺎ ﺳﺘﺨﺪام 5000 " " ﻋ روﺑﻮﺗﻴـﺔ ﺻـﻐ ة أداة ﻓﺈن ) DESI ( ة ﻗﺎدر ﻋـﲆ إﺟـﺮاء ﻫـﺬا ـــــ ا ﻜـﻮن ﻏ ا ﻌﺮوف اﻟﺬي ﺗﻮﺳﻊ ﻛﻮﻧﻨﺎ ﻟﻠﺘﺴﺎرع . ﻳﻘﻮل ﺑﺎت ﻣﻜﺎرﺛﻲ ﻣﺪﻳﺮ ﻣﺨﺘﱪ ﻧﻮﻳﺮﻻب : " ﻟﻘﺪ ﺣﻮﻟﺖ أداة ) DESI ( ﺗﻠﺴـﻜﻮب ﻣﺎﻳـﺎل إﱃ آﻟ ـﺔ رﺳـﻢ اﻟﺨ ـﺮاﺋﻂ اﻟﻜﻮﻧﻴ ـﺔ اﻷوﱃ ﰲ اﻟﻌـﺎﻟﻢ ." ﻟﻘـﺪ وﺿـﻊ ﻓﺮﻳـﻖ أداة ) DESI ( اً ﻣﻌﻴـﺎر اً ﺟﺪﻳـﺪ ﻟﺪراﺳـﺎت اﻟﺒﻨﻴـﺔ واﺳـﻌﺔ اﻟﻨﻄﺎق ﰲ اﻟﻜﻮن . إن ﺑﻴﺎﻧـﺎت اﻟﺴـﻨﺔ اﻷوﱃ ﻫﺬه ﻟﻴﺴﺖ ﺳﻮى ﺑﺪاﻳﺔ ﺳﻌﻲ أداة ) DESI ( ﻟﻜﺸﻒ ﺗﺎرﻳﺦ ﺗﻮﺳﻊ اﻟﻜﻮن وﻫﻲ ﺗﻠﻤـﺢ إﱃ اﻟﻌﻠـﻢ اﻻﺳـﺘﺜﻨﺎﺋﻲ اﻟﻘـﺎدم . ﻟﻘـﺪ ﺳـﻤﺤﺖ ﺑﻴﺎﻧـﺎت اﻟﻌـﺎم اﻷول ﻷ ) ةدا DESI ( ﻟﻌﻠﻤـﺎء اﻟﻔﻠﻚ ﺑﻘﻴﺎس ﻣﻌﺪل ﺗﻮﺳـﻊ اﻟﻜـﻮن إﱃ 11 ﻣﻠﻴﺎر ﺳﻨﺔ ﰲ ا ﺎﴈ ﻋﻨﺪﻣﺎ ﻛﺎن ﻋﻤﺮ اﻟﻜﻮن رﺑﻊ ﻋﻤﺮه اﻟﺤﺎﱄ ﻓﻘﻂ ﻳﺴﺘﺨﺪم ﻳـ ﺎسـ ﻟﻘﻴ ا ﺑﻤﻌﺪل ﻏـ ﻣـﺴـﺒﻮق، ﻓـﻔﻲ ﺎﻣﻬـﻋ ﺎ اﻷول وﺣ ﺪهـ ﺗﺠﺎوزت أداة ) DESI ( ﺟﻤـﻴﻊ اﻟﺪراﺳﺎت اﻻﺳﺘﻘﺼﺎﺋﻴﺔ اﻟﺴﺎﺑﻘ ﺔ ﻣـﻦ ﻧﻮﻋﻬـﺎ ﻣـﻦ ﺣﻴﺚ اﻟﻜﻤﻴﺔ واﻟﻨﻮﻋﻴﺔ وذﻟﻚ ﺑﻌﻤﻖ ودﻗـﺔ ﻣﺘﻨﺎﻫﻴﺔ ﺣﻴﺚ ﻗﺪﻣﺖ أداة ) DESI ( رؤﻳـﺔ ﺟﺪﻳﺪة اﺳﺘﺜﻨﺎﺋﻴﺔ ﻟﻮاﺣﺪ ﻣﻦ أﻛﱪ اﻷﻟﻐـﺎز اﻟﻜﻮﻧﻴـﺔ ﰲ اﻟﻔﻴﺰﻳ ـﺎء اﻟﺤﺪﻳﺜـﺔ : اﻟﻄﺎﻗـﺔ ا ﻈﻠﻤﺔ وﻫﻲ ﺗﻊ - ﻳﻮﻟﻴﻮ ﺃﻏﺴﻄﺲ 2 0 2 4 ا ﻜـﻮن ﻏــ ﻣـ أﻷﺣـ ﻃـ أﻃـﻮ ﺧـ ﺗــﻮ ـ اﻟـ