Free Astronomy Magazine May-June 2026 ARABIC VERSION

MAY-JUNE2026 Preliminary analysis suggests CDG-2 has the luminosity of roughly 1 mil- lion Sun-like stars, with the globular clusters accounting for 16% of its visible content. Remarkably, 99% of its mass, which includes both visible matter and dark matter, appears to bedarkmatter.Muchofitsnormal matter to enable star formation (primarily hydrogen gas) was likely stripped away by gravitational in- teractions with other galaxies inside the Perseus cluster. “TheEucliddataclearlyconfirmthe presenceoftheextremelyfaint,dif- fuselightofCDG-2,revealingthe galaxy behind the globular clusters for the first time,” says Francine MarleaufromtheInstitutefor Astro- and Particle Physics at the University of Innsbruck in Austria. “The Euclid images of the Perseus cluster demonstrate the mission’s unique capability to detect newlow-surface- brightness galaxies, in- cluding extremely faint ones, while also revealing their globular clus- ters, nuclear star clusters, internal structures, and surrounding envi- ronments.” Globular clusters possess immense stellar density and are gravitationally tightly bound. This makes the clusters more resistant to gravitational tidal disruption, and therefore reliable tracers of such ghostlygalaxies.   16 % ﻣﻦ ﻣﺤﺘﻮاﻫﺎ ا ﺮﺋﻲ . وﻣـﻦ اﻟﻼﻓـﺖ أن 99 % ﻣﻦ ﻛﺘﻠﺘﻬﺎ اﻟﺘﻲ ﺗﺸﻤﻞ ﻛﻼً ﻣـﻦ ا ـﺎدة ا ﺮﺋﻴﺔ وا ﺎد ة ا ﻈﻠﻤﺔ ﻳﺒﺪو أﻧﻬﺎ ﻣﺎدة ﻣﻈﻠﻤﺔ وﻣـﻦ ا ـﺮﺟﺢ أن ﺟـﺰء اً اً ﻛﺒـ ﻣـﻦ ﻣﺎدﺗﻬـﺎ اﻟﻌﺎدﻳﺔ اﻟﻼزﻣﺔ ﻟﺘﺸﻜّﻞ اﻟﻨﺠﻮم ) وﺧﺎﺻﺔ ﻏﺎز اﻟﻬﻴﺪروﺟ ( ﻗﺪ ﺗﻢ ﺗﺠﺮﻳﺪه ﺑﻔﻌﻞ اﻟﺘﻔﺎﻋﻼت اﻟﺠﺎذﺑﻴﺔ ﻣﻊ ﻣﺠﺮات أﺧـﺮى داﺧـﻞ ﻋﻨﻘـﻮد ﺑﺮﺳﺎوس . وﺗﻘﻮل ﻓﺮاﻧﺴ ﻣﺎرﻟﻮ ﻣﻦ ﻣﻌﻬـﺪ اﻟﻔﻴﺰﻳﺎء اﻟﻔﻠﻜﻴﺔ وﻓﻴﺰﻳﺎء اﻟﺠﺴﻴﻤﺎت ﺑﺠﺎ ﻣﻌﺔ ﺑﺮﺳﺎوس . وﺗﻘﻮل ﻓﺮاﻧﺴ ﻣﺎرﻟﻮ ﻣﻦ ﻣﻌﻬـﺪ اﻟﻔﻴﺰﻳﺎء اﻟﻔﻠﻜﻴﺔ وﻓﻴﺰﻳﺎء اﻟﺠﺴﻴﻤﺎت ﺑﺠﺎﻣﻌﺔ إﻧﺴﱪوك ﰲ اﻟﻨﻤﺴﺎ :» ﺗﺆﻛﺪ ﺑﻴﺎﻧـﺎت إﻗﻠﻴـﺪس ﺑﻮﺿﻮح وﺟﻮد اﻟﻀﻮء اﻟﺨﺎﻓﺖ ﺟﺪًا وا ﻨﺘﴩ ـ ﺠـﺮة CDG-2 ﻛﺎﺷـﻔﺔً ﻋـﻦ ا ﺠـﺮة ﺧﻠـﻒ اﻟﻌﻨﺎﻗﻴﺪ اﻟﻜﺮوﻳـﺔ ﻟﻠﻤـﺮة اﻷوﱃ « . وأﺿـﺎﻓﺖ : » ﺗُﻈﻬﺮ ﺻـﻮر إﻗﻠﻴـﺪس ﻟﻌﻨﻘـﻮد ﺑﺮﺳـﺎوس اﻟﻘﺪرة اﻟﻔﺮﻳﺪة ﻟﻠﻤﻬﻤﺔ ﻋﲆ اﻛﺘﺸﺎف ﻣﺠﺮات اﻟﻘﺪرة اﻟﻔﺮﻳﺪة ﻟﻠﻤﻬﻤﺔ ﻋﲆ اﻛﺘﺸﺎف ﻣ ﺠﺮات ﺟﺪﻳﺪة ﻣﻨﺨﻔﻀﺔ اﻟﺴﻄﻮع اﻟﺴﻄﺤﻲ ﺑﻤـﺎ ﰲ ذﻟﻚ ﺗﻠﻚ اﻟﺨﺎﻓﺘـﺔ ﻟﻠﻐﺎﻳـﺔ إﱃ ﺟﺎﻧـﺐ ﻛﺸـﻒ ﻋﻨ ﺎﻗﻴ ـﺪﻫﺎ اﻟﻜﺮوﻳ ـﺔ وﻋﻨﺎﻗﻴ ـﺪﻫﺎ اﻟﻨﺠﻤﻴ ـﺔ اﻟﻨﻮوﻳﺔ وﺑ ﻨ ﺎﻫﺎ اﻟﺪاﺧﻠﻴﺔ وﺑﻴﺌﺎﺗﻬﺎ ا ﺤﻴﻄﺔ «. ﻛﻤﺎ أن اﻟﺠﻤﻊ ﺑ ﺑﻴﺎﻧﺎت ﻣﺘﻌﺪدة ﻣﻦ ﻣﺮاﺻﺪ ﻓﻀﺎﺋﻴﺔ وأرﺿﻴﺔ ﻣﻜّﻦ ﻣﻦ ﺑﻨﺎء ﺻـﻮرة أﻛﺜـﺮ ﺗﻜﺎﻣﻼً ﻟﻬﺬه اﻷﺟﺮام اﻟﺨﺎﻓﺘﺔ ﻣﺎ ﻳﻌﺰز ﻓﻬﻤﻨـﺎ ﻟﺘﻮزﻳﻊ ا ﺎدة ا ﻈﻠﻤﺔ ودورﻫﺎ ﰲ ﺗﺸﻜﻞ اﻟﺒﻨﻰ اﻟﻜﻮﻧﻴﺔ وﺗﻔﺘﺢ ﻫـﺬه اﻟﻨﺘـﺎﺋﺞ آﻓﺎﻗًـﺎ ﺟﺪﻳـﺪ ة ﻟﺪراﺳﺔ ا ﺠﺮات اﻟﺸﺪﻳﺪة اﻟﺨﻔﻮت اﻟﺘـﻲ ﻗـﺪ ﺗﻜﻮن أﻛﺜﺮ ﺷﻴﻮﻋ ﺎً ﻣﻤﺎ ﻛﺎن ﻳُﻌﺘﻘﺪ . ﺗﻤﺘﻠﻚ اﻟﻌﻨﺎﻗﻴﺪ اﻟﻜﺮوﻳﺔ ﻛﺜﺎﻓﺔ ﻧﺠﻤﻴﺔ ﻫﺎﺋﻠـﺔ وﺗﺮﺗﺒﻂ ﺟ ﺎً ﺬﺑﻴ ﺑﺸﻜﻞ ﻣﺤﻜﻢ ﻣﺎ ﻳﺠﻌﻠﻬﺎ أﻛﺜﺮ ﻣﻘﺎو ﻣﺔ ﻟﻠﺘﺸﻮﻫﺎت اﻟﻨﺎﺟﻤﺔ ﻋـ ﻦ ﻗـﻮى ا ـﺪ اﻟﺠ ﺬﺑﻴﺔ وﺑﺎﻟﺘﺎﱄ ﺗ ﻌﺪ ﻣﺆﴍات ﻣﻮﺛﻮﻗﺔ ﻟﺘﺘﺒﻊ ﻣﺜﻞ ﻫﺬ ه ا ﺠﺮات اﻟﺸﺒﺤﻴﺔ . ﺗﻬ ﻤﻦ اﻟﻤﺎدة اﻟﻤﻈﻠﻤﺔ ﻋﻠﻰ اﻟ ﻤﺠﺮة CDG-2 ذات اﻟﺴﻄﻮع اﻟﺴـﻄﺤﻲ اﻟﻤـﻨﺨﻔﺾ ﻤـﺎ ﻫـﻮ ﻣﻮﺿـﺢ ﻓــﻲﻫــﺬﻩ اﻟﺼــﻮرة اﻟﻤﻠﺘﻘﻄــﺔ ﺑﻮاﺳـــﻄﺔ ﺗﻠﺴــ ﻮبﻫﺎﺑــﻞ اﻟﻔﻀــﺎﺋﻲ اﻟﺘـــﺎﺑﻊ ﻟﻮ ﺎﻟــﺔ ﻧﺎﺳــﺎ وو ﺎﻟــﺔ اﻟﻔﻀـــﺎء ـــﺔ وﻻ ﺗﺤﺘـــﻮي إﻻ ﻋﻠـــﻰﻋـــﺪد ﻗﻠﻴـــﻞ ﻣـــﻦ اﻟﻨﺠـــﻮم اﻟﻤﺘﻨـــﺎﺛﺮة اﻷوروﺑ . ﻫـــﺬﻩ اﻟﻤﺠـــﺮة ﺷـــ ﮫ ﻏـــ ـــﺔ وﻟﻜـــﻦ ﻣﺮ ـــﺎت ﻣﺘﻘﺪﻣـــﺔ ﺎﺳـــﺘﺨﺪام ﺗﻘﻨ ﺗــــﻢ ـــﺪﻫﺎ ﻣـــﻦ ﺧــــﻼل اﻟﺒﺤـــﺚ ﻋـــﻦ ﺗ ﻤﻌـــﺎت ﻛﺜ ﻔــــﺔ ﻣـــﻦ اﻟﻨﺠـــﻮم ﺗﺴــــﻤﻰ ﺗﺤﺪ اﻟﻌﻨﺎﻗ ﺪ اﻟﻜﺮو ﺔ . ﺗﻮﺟﺪ ﺗﻢ ﻓﺤﺼﻬﺎ وﻋﻠﻰ اﻟ ﻤ ﻋﻠﻰ اﻟ ﺴﺎر ﺸ اﻟﻤﺮﻊ اﻷﺑ ﺾ إﻟﻰ اﻟﻤﻨﻄﻘﺔ اﻟ ﺻﻮرة ﻣﻜ ة ﻟﺘﻠﻚ اﻟﻤﻨﻄﻘﺔ . ﺗﺸ اﻟﺪاﺋﺮة اﻟﻤﺤﺪدة ﺑﺨﻂ أ ﻤﺮﻣﺘﻘﻄﻊ إﻟﻰﻣﻮﻗﻊ اﻟﻤ ﺗﻬ ﻤﻦ ﺠﺮة اﻟ ﻋﻠﻴﻬـــﺎ اﻟﻤـــﺎدة اﻟﻤﻈﻠﻤـــﺔ . ـــﺪواﺋﺮ زرﻗـــﺎء ـــﺔ ﻣﺤـــﺪدة ـــﺪ ﻛﺮو داﺧـــﻞ اﻟـــﺪاﺋﺮة اﻟﻤﺘﻘﻄﻌـــﺔ ﺗﻮﺟـــﺪ أرﻌـــﺔ ﻋﻨﺎﻗ . ﺻﻐ ة ﻤﺎ ﺗﻈﻬﺮ ﻋﺪة ﻣﺠﺮات داﺧﻞ اﻟﺪاﺋﺮة اﻟ ـ ﻤﺮاء وﻟﻜﻨﻬﺎ ﻻ ﺗﺮ ﻂ ﺎﻟﻤﺠﺮة CDG-2 . [NASA, ESA, D. Li(Utoronto), Image Processing: J. DePasquale (STScI)] اﻟﻌﻨﺎﻗ ﺪ اﻟﻜﺮو ﺔ ﻣﺠﺮة ﻣﻈﻠﻤﺔ ﻣﺤﺘﻤﻠﺔ – اﻻﻧ ﻌﺎث اﻟﻤ ﻌ -ﻳﻮﻣﺎ ﻳﻮﻧﻴﻮ 2 0 2 6