Free Astronomy Magazine May-June 2026 ARABIC VERSION

strongly enriched in methanol com- pared to hydrogen cyanide. On two observing dates, the researchers measuredmethanol-to-HCNratiosof about 70 and 120, placing 3I/- ATLAS among the most methanol- rich comets ever studied. These measurements suggest that theicymaterialmakingup3I/ATLAS formed—or was processed—under conditionsdifferentfromthosethat shapedmostcometsinourSolarSys- tem.Previousobservationswiththe JamesWebbSpaceTelescopehadal- readyshownthatthecomet’scoma was dominated by carbon dioxide when it was farther from the Sun. The new ALMA observations add methanoltoitsunusualchemicalin- ventoryasanotherkeycomponent. ALMA’shigh-resolutionimagingalso allowedastronomerstostudyhow different molecules move away from the comet. Hydrogen cyanide ap- pears to originate mainly from the comet’s nucleus, which is typical for Solar System comets. Methanol, however, appears to be released both from the nucleus and from icy grains in the coma. These tiny parti- cles act like miniature comets: as theyarewarmedbysunlight,theice they contain turns into gas and re- leases methanol into the surround- ing coma. While similar behavior has been observed in some Solar System comets,thisisthefirsttimesuchde- tailed outgassing processes have beentracedinaninterstellarobject. Comet3I/ATLASisonlythethirdcon- firmed interstellar visitor detected passing through our Solar System, following 1I/‘Oumuamua and 2I/Bo- risov. Observations of these rare ob- jects continue to provide valuable clues about how planetary systems formandevolveacrosstheGalaxy.     MAY-JUNE2026 ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 33 ا ﺬﻧﺐ 3I/ATLAS ﺿﻤﻦ أﻛﺜﺮ ا ﺬﻧﺒﺎت اﻟﺘﻲ رﺳﺖ د ﻏﻨﻰً ﺑﺎ ﻴﺜﺎﻧﻮل ﻋﲆ اﻹﻃﻼق . ﺗﺸ ﻫﺬه اﻟﻘﻴﺎﺳﺎت إﱃ أن ا ـﻮاد اﻟﺠﻠﻴﺪﻳـﺔ اﻟﺘﻲ ﻳﺘﻜﻮّن ﻣﻨﻬﺎ 3I/ATLAS ﻗﺪ ﺗﺸﻜّﻠﺖ أو ﺧﻀﻌﺖ ﻟﻌﻤﻠﻴﺎت ﻣﻌﺎﻟﺠﺔ ﰲ ﻇﺮوف ﺗﺨﺘﻠـﻒ ﻋﻦ ﺗﻠﻚ اﻟﺘﻲ ﺷﻜّﻠﺖ ﻣﻌﻈﻢ ﻣﺬﻧﺒﺎت ﻧﻈﺎﻣﻨـﺎ اﻟﺸﻤ ﻛﺎﻧﺖ و . ﴘـ أرﺻﺎد ﺳﺎﺑﻘﺔ ﺑﺎﺳـﺘﺨﺪام ﺗﻠﺴﻜﻮب ﺟﻴﻤﺲ وﻳﺐ اﻟﻔﻀﺎﺋﻲ ﻗﺪ أﻇﻬـﺮت أن ذؤاﺑﺔ ا ـﺬﻧﺐ ﻛـﺎن ﻳﻐﻠـﺐ ﻋﻠﻴﻬـﺎ ﺑﺜـﺎﻧﻲ أﻛﺴﻴﺪ اﻟﻜﺮﺑﻮن ﻋﻨﺪﻣﺎ ﻛﺎن أﺑﻌﺪ ﻋﻦ اﻟﺸﻤﺲ . ـــــــــــــــــــــــــــــــــــــ وﺗﻀﻴﻒ أرﺻﺎد ﻣﺮﺻﺪ أ ﺎ اﻟﺠﺪﻳﺪة ا ﻴﺜـﺎﻧﻮل إﱃ ﺗﺮﻛﻴﺒﺘﻪ اﻟﻜﻴﻤﻴﺎﺋﻴﺔ ﻏ ا ﻌﺘﺎدة ﺑﻮﺻـﻔﻪ ﻣﻜﻮّﻧًﺎ رﺋﻴﺴـﻴ ﺎً آﺧـﺮ . ﻛﻤـﺎ أﺗﺎﺣـﺖ اﻟﻘـﺪرة اﻟﻌﺎﻟﻴﺔ ﻋﲆ اﻟﺘﺼﻮﻳﺮ اﻟـﺪﻗﻴﻖ ﺼـﻔﻮﻓﺔ أ ـﺎ ﻟﻌﻠﻤﺎء اﻟﻔﻠﻚ دراﺳﺔ ﻛﻴﻔﻴﺔ اﺑﺘﻌﺎد اﻟﺠﺰﻳﺌـﺎت ا ﺨﺘﻠﻔــﺔ ﻋـﻦ ا ــﺬﻧﺐ . وﻳﺒ ـﺪو أن ﺳــﻴﺎﻧﻴﺪ اﻟﻬﻴﺪر وﺟ ﻳﻨﺸ أ ﺄ ﺄﺳﺎﺳ ﻣـﻦ ﻧـﻮاة ا ـﺬﻧﺐ وﻫــﻮ ﺳــﻠﻮك ﻧﻤ ـﻮذﺟﻲ ــﺬﻧﺒ ﺎت اﻟﻨﻈــﺎم اﻟﺸﻤﴘ . أﻣﺎ ا ﻴﺜﺎﻧﻮل ﻓﻴﺒﺪو أﻧﻪ ﻳ ﻄﻠـﻖ ﻣـﻦ اﻟﻨﻮاة و ﻛـﺬﻟﻚ ﻣـﻦ ﺣﺒﻴﺒـﺎت ﺟﻠﻴﺪﻳـﺔ داﺧـﻞ ـــــــــــــــــــــــــــــــــــــ اﻟﺬؤاﺑﺔ وﺗﻌﻤـﻞ ﻫـﺬه اﻟﺠﺴـﻴﻤﺎت اﻟﺼـﻐ ة ﻛﻤﺬﻧﺒﺎت ﻣﺼﻐّﺮة : ﻓﻌﻨﺪﻣﺎ ﺗﺴـﺨﻨﻬﺎ أﺷـﻌﺔ اﻟﺸﻤﺲ، ﻳﺘﺤﻮل اﻟﺠﻠﻴﺪ اﻟﺬي ﺗﺤﺘﻮﻳﻪ إﱃ ﻏ ﺎز، ﻣﻄﻠﻘًﺎ ا ﻴﺜﺎﻧﻮل ﰲ اﻟﺬؤاﺑﺔ ا ﺤﻴﻄﺔ . ورﻏﻢ أن ﺎً ﺳﻠﻮﻛ ﺎً ﻣﺸﺎﺑﻬ ﻗﺪ ﻟ ﻮﺣﻆ ﰲ ﺑﻌـﺾ ﻣـﺬﻧﺒﺎت اﻟﻨﻈﺎم اﻟﺸﻤﴘ ﻓﺈن ﻫﺬه ﻫﻲ ا ﺮة اﻷوﱃ اﻟﺘﻲ ﻳﺘﻢ ﻓﻴﻬﺎ ﺗﺘﺒّﻊ ﻣﺜﻞ ﻫﺬه اﻟﻌﻤﻠﻴﺎت اﻟﺘﻔﺼﻴﻠﻴﺔ ﻻﻧﺒﻌﺎث اﻟﻐﺎزات ﰲ ﺟﺴﻢ ﺑ ﻧﺠﻤﻲ . وﺗﻮﻓﺮ ﻫﺬه اﻟﻨﺘﺎﺋﺞ إﻃﺎر اً ﺗﺤﻠﻴﻠﻴ ﺎً ﻣﻬﻤ ﺎً ﻟﻔﻬﻢ آﻟﻴ ـﺎت اﻟﺘﺴ ـﺎﻣﻲ وﺗﺤ ـﺮ ر اﻟﺠﺰﻳﺌ ـﺎت ﻣ ـﻦ اﻟﺤﺒﻴﺒﺎت اﻟﺠﻠﻴﺪﻳﺔ ﻛﻤـﺎ ﺗﻌـﺰز اﻟﻘـﺪرة ﻋـﲆ ﻣﻘﺎرﻧﺔ اﻟﺨﺼﺎﺋﺺ اﻟﻜﻴﻤﻴﺎ ﺋﻴﺔ ﺑـ ﻣـﺬﻧﺒﺎت اﻷﻧﻈﻤﺔ ا ﺨﺘﻠﻔﺔ وﺗﺴﺎﻋﺪ ﰲ ﺑﻨﺎء ﻧﻤﺎذج أدق ﻟﺘﺎرﻳﺦ ﺗﺸﻜﻞ ا ﻮاد اﻟﻌﻀﻮﻳﺔ وﺗﻄﻮرﻫﺎ ﻋـﱪ اﻟﺒﻴﺌﺎت اﻟﻨﺠﻤﻴﺔ ا ﺘﻨﻮﻋﺔ ﻳ ﻌﺪ ا ﺬﻧﺐ 3I/ATLAS ﺛﺎﻟﺚ زاﺋﺮ ﺑ ﻧﺠﻤﻲ ﺘﺸﻒﻜ ﻣﺆﻛﺪ ﻳ ﻣﺮوره ﻋﱪ ﻧﻈﺎﻣﻨﺎ اﻟﺸـ ﻤﴘـ ﺑﻌﺪ 1I/ أﻣﻮاﻣﻮا و 2I/ ﺑﻮرﺳﻮف . ﺗﺴﺘﻤﺮ دراﺳﺔ ﻫﺬه ا ﻷﺟﺮام اﻟﻨﺎدرة ﰲ ﺗﻘـﺪﻳﻢ أدﻟﺔ ﻗﻴ ﻤﺔ ﺣﻮل ﻛﻴﻔﻴﺔ ﺗﺸﻜّﻞ وﺗﻄﻮر اﻷﻧﻈﻤﺔ اﻟﻜﻮﻛﺒﻴﺔ ﻋﱪ ﻣﺠﺮﺗﻨﺎ . - ﻣﺎﻳﻮ ﻳﻮﻧﻴﻮ 2 0 2 6 رﺳﻢ ﺗﺨ ﻠﻲ ﻟﻠﻤﺬﻧﺐ 3I/ATLAS ﻈﻬﺮأﺛﻨﺎء ﻣﺮورﻩ ﺎﻟﻘﺮ ﻣﻦ اﻟﺸﻤﺲﻣﻀﻴﺌﺎً أﺣﺪ ﺟﺎﻧﺒ ﮫ . ﻋﻠــــــﻰﺟﺎﻧــــــﺐ اﻟﻤــــــﺬﻧﺐ اﻷﻗــــــﺮ إﻟــــــﻰ اﻟﺸــــــﻤﺲ ــﺎﻟﻠﻮن اﻷزرق ﻈﻬــﺮﻏــﺎز اﻟﻤ ﺜــﺎﻧﻮل ﻣــﻊ وﺟــﻮد ــــــﺔ ﻻ ﺗـــــﺰال ﻣﻮﺟــــــﻮدة ﻓــــــﻲ ــــــﺎرﺟﻠ ﺪ ـــــﺎت ﻏ ﺣﺒﻴ اﻟﻐــﺎز . ـ ﻋﻠــﻰ اﻟـــ ﺠﺎﻧﺐ اﻷﺧــﺮ ﻣـــﻦ اﻟﻤــﺬﻧﺐ ﻈﻬـــﺮ ﺎﻟﻠﻮن اﻟ ﻘﺎﻟﻲ ﺳ ﺎﻧ ﺪ اﻟﻬ ﺪروﺟ . [NSF/AUI/NSFNRAO/M.Weiss]