Free Astronomy Magazine November-December 2025 ARABIC VERSION

Elusive cloud-forming chemical on ancient brown dwarf by NOIRLab Josie Fenske rown dwarfs are peculiar ob- jects that are too massive to be consideredplanets,butnotmassive enough to sustain nuclearfusionlikeastar.Amongthiscuri ous classofobjects,abrowndwarfnick- named The Accident stands out for its unique mix of physical features, exhibiting characteristics previously seenonlyinwarm,youngbrown dwarfs and others previously seen onlyincool,ancientones.TheAcci- dent’spropertiesarehighlyunusual compared to all other known stars andbrowndwarfs,soitslippedpast typical detection methods. It was discoveredaccidentallyin2020bya citizenscientistparticipatinginthe BackyardWorlds:Planet9citizensci- enceproject.Itsstrangelightprofile piquedtheinterestofastronomers, sotheyturnedtotwooftheworld’s most powerful ground- and space- basedtelescopestopeerintoitsat- mosphereandbetterunderstandits nature and composition. The investigation began with NSF NOIRLabastronomerSandyLeggett obtaining near-infrared images of TheAccidentusingtheGeminiSouth NOVEMBER-DECEMBER2025 ﻗﺪ ﻢ ﻳﺨﺘ ء وراء ﻗﺰم ﺳﺤﺎ ﺔ ﻛ ﻤ ﺎﺋ ﺔ ﻏﺎﻣﻀﺔ : ﻘﻠﻢ ﺟﻮزيﻓ ﻨﺴﻜﻲ ﻣﺨﺘ ﻧﻮﻳﺮﻻب ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 20 اﻷﻗـﺰام اﻟﺒﻨﻴﺔ ﻫﻲ أﺟﺮام و ﻏﺮﻳﺒـﺔ ﺿـﺨﻤﺔ ﻧﺴـﺒﻴﺎً ﺑﺤﻴـﺚ ﻻ ﻳﻤﻜـﻦ اﻋﺘﺒﺎرﻫـﺎ ﻛﻮ اﻛـﺐ وﻟﻜﻨﻬﺎ ﻟﻴﺴـﺖ ﺿـﺨﻤﺔ ﺑﻤـﺎ ﻳﻜﻔـﻲ ﻟـﺪﻋﻢ اﻻﻧﺪﻣﺎج اﻟﻨﻮوي ﻣﺜﻞ اﻟﻨﺠﻮم وﻣﻦ ﺑـ ﻫـﺬه اﻟﻔﺌﺔ اﻟﻐﺮﻳﺒﺔ ﻣﻦ اﻷﺟﺮام ﻳﱪز اﻟﻘـﺰم اﻟﺒﻨـﻲ ا ﻠﻘﺐ ﺑ اﻟﺤﺎدث "ـ " وﻫﻮ ﺟﺮم ﻳﺘﻤﻴﺰ ﺑﻤﺰﻳﺞ ﻣﻦ اﻟﺴﻤﺎت اﻟﻔﻴﺰﻳﺎﺋﻴﺔ اذ ﻳﻈﻬـﺮ ﺧﺼـﺎﺋﺺ ﺷﻮﻫﺪت ﺎً ﺳـﺎﺑﻘ ﰲ اﻷﻗـﺰام اﻟﺒﻨﻴـﺔ اﻟﺸـﺎﺑﺔ واﻟﺪاﻓﺌﺔ وأﺧﺮى ﺷﻮﻫﺪت ﺳـﺎﺑﻘًﺎ ﰲ اﻷﻗـﺰام اﻟﺒﻨﻴﺔ اﻟﻘﺪﻳﻤﺔ اﻟﺒﺎردة . إن ﺧﺼﺎﺋﺺ اﻟﺤﺎدث اﻟﻘﺪﻳﻤﺔ اﻟﺒﺎردة . إن ﺧﺼﺎﺋﺺ اﻟﻘـﺰم اﻟﺒﻨـﻲ اﻟﺤﺎدث " " ﻏ ﻋﺎدﻳﺔ ﻋﲆ اﻹﻃـﻼق ﻣﻘﺎرﻧـﺔ ﺑﺠﻤﻴــﻊ اﻟﻨﺠـﻮم واﻷﻗـﺰام اﻟﺒﻨﻴ ـﺔ اﻷﺧـﺮى ا ﻌﺮوﻓﺔ ﺣﺘﻰ اﻧﻪ ﺗﺠـﺎوز اﺳـﺎﻟﻴﺐ اﻟﻜﺸـﻒ ا ﻌﺘﺎدة ﺗﻢ . اﻛﺘُﺸ ﻪﻓﺎ ﺑﺎﻟﺼـﺪﻓ ﺔ ﻋـﺎم 2020 ﻋﲆ ﻳﺪ اﺣﺪ اﻟﻌﻠﻤﺎء ا ﺸـﺎرﻛ ـ ﰲ ﻣـ ﴩوع " ﻋﻮاﻟﻢ اﻟﻔﻨﺎء اﻟﺨﻠﻔﻲ : اﻟﻜﻮﻛﺐ 9." ﻟﻘﺪ ﻟﻔﺖ ﺿﻮءه اﻟﻐﺮﻳﺐ اﻫﺘﻤـﺎم اﻟ ﻌﻠﻤـﺎء ﻓﻠﺠـﺄوا إﱃ اﺛﻨ ـ ﻣ ـﻦ أﻗ ـﻮى اﻟﺘﻠﺴ ـﻜﻮﺑﺎت اﻷرﺿ ـﻴﺔ واﻟﻔﻀﺎﺋﻴﺔ ﰲ اﻟﻌﺎﻟﻢ ﻟﻠﻨﻈﺮ ﰲ ﻏﻼﻓﻪ اﻟﺠـﻮي واﻟﻔﻀﺎﺋﻴﺔ ﰲ اﻟﻌﺎﻟﻢ ﻟﺪراﺳﺔ ﻏﻼﻓـﻪ اﻟﺠـﻮي وﻓﻬﻢ ﻃﺒﻴﻌﺘﻪ وﺗﻜﻮﻳﻨﻪ ﺑﺸﻜﻞ أﻓﻀﻞ . ﺑﺪأ اﻟﺒﺤﺚ ﻣﻊ ﻋﺎ ﺔ اﻟﻔﻠﻚ ﺳﺎﻧﺪي ﻟﻴﺠﻴﺖ ﻣﻦ ﻣﺨﺘﱪ ﻧﻮﻳﺮ ﺣﻴﺚ ﺖﺣﺼﻠ ﻋﲆ ﺻﻮر ﺑﺎﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤﺮاء اﻟﻘﺮﻳﺒﺔ ﻟﻠﻘﺰم اﻟﺒﻨﻲ ﺑﺎﺳﺘﺨ ﺪام ﺗﻠﺴﻜﻮب ﺟﻴﻤﻴﻨﻲ ﺳـﺎوث اﻟﻮاﻗـﻊ ﰲ ﺗﺸـﻴﲇ ﺟﺰء وﻫﻮ ﻣﻦ ﻣﺮﺻﺪ ﺟﻴﻤﻴﻨـﻲ اﻟـﺪوﱄ اﻟـﺬي ﺗﻤﻮﻟﻪ ﻣﺆﺳﺴﺔ اﻟﻌﻠـﻮم اﻟﻮﻃﻨﻴـﺔ اﻷﻣﺮﻳﻜﻴـﺔ وﻳﺪﻳﺮه ﻣﺨﺘﱪ ﻧﻮﻳﺮ اﻟﺘﺎﺑﻊ ﻟ ﻠﻤﺆﺳﺴﺔ . ﻧﻮﻓﻤﺒﺮ - ﺩﻳﺴﻤﺒﺮ 2 0 2 5