Free Astronomy Magazine November-December 2025 ARABIC VERSION

hisartist’sillustrationshowsabrown dwarfthathostsanatmosphere filledwithgasanddustclouds.Anew study on an ancient brown dwarf called The Accident has unlocked clues into how cloudsliketheseformongasgiantplanets and how the time at which they formed can impact their chemical composition. [NOIRLab/NSF/AURA/R.Proctor.ImagePro- cessing: M. Zamani (NSF NOIRLab). ProducedinpartwithSpaceEnginePRO] telescopeinChile,onehalfoftheIn- ternational Gemini Observatory, funded in part by the U.S. National Science Foundation (NSF) and oper- ated by NSF NOIRLab. This laid the groundwork for further investiga- tions, led by NOIRLab astronomer Aaron Meisner, using NASA’s James Webb Space Telescope. “The Acci- dentisextremelyfaint,andGemini South remains the only ground- based telescope that’s so far been able to detect it,” says Meisner, co- author of the article that presented theseresultsin Nature . “TheGemini detection set the stage for observa- tionswithJWSTbyallowingustoes- timate the exposure time we would need to probe this enigmatic ob- ject’sdeepatmosphericlayersand get useful near-infrared data about its composition.” The observations from Webb revealed a surprise. NOVEMBER-DECEMBER2025 T ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 21 ﻈﻬـﺮ ﻫــﺬا اﻟ ﺮﺳــﻢ اﻟﺘﺨ ﻠـﻲ ﻗﺰﻣــﺎً ــﺎً ﻨ ﻳ ﻤــﻞ ﻏﻼﻓــﺎً ﺟﻮ ﺎً ﻣﻠﻴﺌﺎً ـﺎر ﺴـﺤﺐ اﻟﻐـﺎزواﻟﻐ وﻗـﺪ ﻛﺸـﻔﺖ دراﺳـﺔ ﻋﻦ ﺟﺪ ﺪة ﻗـﺪ ﻢ ﻗﺰم ـ اﻟـ " ﺴـﻤﻰ " ﺤﺎدث ﻋـﻦ أدﻟـﺔ ــــــﺔ ﺗﺸــــــ ﻞﺳــــــﺤﺐ ﻬــــــﺬﻩ ﺣــــــﻮل ﻛ ﻔ ﻋﻠــــــﻰ اﻟ ﻮاﻛــــــﺐ اﻟﻐﺎز ــــﺔ اﻟﻌﻤﻼﻗـــــﺔ ــــﻒ ﻳـــــﺆﺛﺮ وﻛ زﻣــــﻦ ﺗﺸـــــ ّﻠﻬﺎ ﻋﻠـــــﻰ ﺗﺮﻛﻴﺒﻬﺎ اﻟﻜ ﻤ ﺎﺋﻲ . ﺸ ﻞ واﺿﺢ [NOIRLab/NSF/AURA/R.Proctor.ImageP ro- cessing: M. Zamani (NSF NOIRLab). ProducedinpartwithSpaceEnginePRO] ﻟﻘﺪ ﻣﻬ ﺪ ﻫـﺬا اﻟﻄﺮﻳـﻖ ﺰﻳـﺪ ﻣـﻦ اﻷﺑﺤـﺎث ﺑﻘﻴﺎدة ﻋﺎﻟﻢ اﻟﻔﻠﻚ آرون ﻣﺎﻳﺴﻨﺮ ﻣﻦ ﻣﺨﺘـﱪ ﻧﻮﻳﺮﻻب ﺑﺎﺳﺘﺨﺪام ﺗﻠﺴﻜﻮب وﻳﺐ اﻟﻔﻀـﺎﺋﻲ اﻟﺘﺎﺑﻊ ﻟ ﻮﻛﺎﻟﺔ و . ﻧﺎﺳﺎ ﻳﻘـﻮل ﻣﺎﻳﺴـﻨﺮ وﻫـﻮ ا ﺆﻟﻒ ا ﺸﺎرك ﻟﻠﻤﻘﺎﻟ ﺔ اﻟﻌﻠﻤﻴﺔ اﻟﺘﻲ ﻋﺮﺿﺖ ﻫﺬه اﻟﻨﺘﺎﺋﺞ اﻟﺠﺪﻳـﺪة ﰲ ﻣﺠﻠـﺔ ﻧﻴﺘﴩـ " : إن اﻟﻘﺰم اﻟﺒﻨﻲ ا ﺴﻤﻰ اﻟﺤﺎدث " " ﺧﺎﻓﺖ ﻟﻠﻐﺎﻳﺔ وﻳﻈﻞ ﺗﻠﺴﻜﻮب ﺟﻴﻤﻴﻨﻲ ﺳﺎوث اﻟﺘﻠﺴـﻜﻮب اﻷرﴈ اﻟﻮﺣﻴﺪ اﻟﺬي ﺗﻤﻜﻦ ﻣـﻦ اﻛﺘﺸـﺎﻓﻪ ." وﻳﻀﻴﻒ " : ﻣﻬﺪ اﻛﺘﺸـﺎف ﺟﻴﻤﻴﻨـﻲ اﻟﻄﺮﻳـﻖ ﻹﺟﺮاء ﻋﻤﻠﻴﺎت رﺻـﺪ ﺑﺎﺳـﺘﺨﺪام ﺗﻠﺴـﻜﻮب وﻳﻀـﻴﻒ ﺎﻳﺴـﻨﺮ ﻣ " : ﻟﻘ ـﺪ ﻣﻬ ـﺪ اﻛﺘﺸـﺎف ﺗﻠﺴﻜﻮب ﺟﻴﻤﻴﻨﻲ ﺳـﺎوث اﻟﻄﺮﻳـﻖ ﻹﺟـﺮاء ﻋﻤﻠﻴﺎت رﺻـﺪ ﺑﺎ ﺳـﺘﺨﺪام ﺗﻠﺴـﻜﻮب وﻳـﺐ اﻟﻔﻀﺎﺋﻲ إذ ﺳـﻤﺢ ﻟﻨـﺎ ذﻟـﻚ ﺑﺘﻘـﺪﻳﺮ زﻣـﻦ اﻟﺘﻌﺮض ا ﻨﺎﺳﺐ اﻟ ﻻﺧﱰاق ﻄﺒﻘﺎت اﻟﻌﻤﻴﻘﺔ ﻣﻦ اﻟﻐـﻼف اﻟﺠـﻮي ﻟﻬـﺬا اﻟ ﺠـﺮم اﻟﻐـﺎﻣﺾ واﻟﺤﺼﻮل ﻋﲆ ﺑﻴﺎﻧﺎت ﻗﻴﻤﺔ ﰲ ﻧﻄﺎق اﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤﺮاء اﻟﻘﺮﻳﺒﺔ ﺣﻮل ﺗﺮﻛﻴﺒﻪ ." ﻛﺸﻔﺖ ﻋﻤﻠﻴﺎت اﻟﺮﺻﺪ اﻟﺘﻲ أﺟﺮاﻫﺎ ﺗﻠﺴـﻜﻮب وﻳـﺐ ﻋﻦ ﻣﻔﺎﺟﺄة ﰲ اﻟﻐﻼف اﻟﺠﻮي ﻟﻠﻘـﺰم اﻟﺒﻨـﻲ وﺟﺪ اﻟﻔﺮﻳﻖ دﻟﻴﻼً ﻗﺎﻃﻌﺎً ﻋﻦ ﻣﻔ ﺎﺟﺄة ﰲ اﻟﻐﻼف اﻟﺠﻮي ﻟﻠﻘـﺰم اﻟﺒﻨـﻲ اﻟﺤﺎدث " ﻓﻘﺪ " وﺟﺪ اﻟﻔﺮﻳﻖ دﻟﻴﻼً ﻗﺎﻃ ﻌﺎً ﻋـﲆ وﺟﻮد ﺟﺰيء اﻟﺴﻴﻼن وﻫﻮ ﻣﺮﻛﺐ ﻛﻴﻤﻴـﺎﺋﻲ ﻳﺘﻜﻮن ﻣﻦ ذرة ﺳﻴﻠﻜﻮن ﺔ ﻣﺮﺗﺒﻄ ﺑﺄرﺑﻊ ذرات ﻫﻴﺪروﺟ . ﻟﻄﺎ ﺎ ﺗﻮﻗﻊ اﻟ ﻌﻠﻤﺎء وﺟـﻮد ﻫـﺬا اﻟﺠ ﺰيء ﰲ اﻟﻜﻮاﻛﺐ اﻟﻐﺎزﻳﺔ اﻟﻌﻤﻼﻗـﺔ واﻧـﻪ ﻳﻠﻌﺐ دور اً ﰲ ﺎً ﻫﺎﻣـ ﺗﻜـﻮﻳﻦ اﻟﺴـﺤﺐ داﺧـﻞ أﻏﻠﻔﺘﻬﺎ اﻟﺠﻮﻳـ ﻮ ﻣﻤـﺎ ﻳﻌـﺰز ﻓﻬـﻢ اﻟﻌﻠﻤـﺎء ﻟﻜﻴﻔﻴ ـﺔ ﻧﺸـﻮء وﺗﻄـﻮر اﻷﺟـﺮام اﻟﻜﻮﻧﻴ ـﺔ وﺗﻔﺴ اﻟﻌﻤﻠﻴﺎت اﻟﻜﻴﻤﻴﺎﺋﻴﺔ اﻟﻘﺪﻳﻤﺔ . ﻧﻮﻓﻤﺒﺮ - ﺩﻳﺴﻤﺒﺮ 2 0 2 5