Free Astronomy Magazine May-June 2026 ARABIC VERSION

A ALMA detects extremelyabundant alcohol in 3I /ATLAS by ALMAObservatory NicolásLira,JillMalusky, BárbaraFerreira,YuichiMatsuda stronomers using the Ata- cama Large Millimeter/sub- millimeterArray(ALMA) have detected an unusually large amount of the organic molecule methanol in the interstellar comet 3I/ATLAS, revealing chemical condi- tions unlike those found in most comets of our own Solar System. Theobservationsshowthat3I/ATLAS contains significantly more meth- anol than hydrogen cyanide, unlike nearly all previously studied comets. These findings provide a rare oppor- tunity to study the chemistry of planetary systems beyond our own. “Observing 3I/ATLAS is like taking a fingerprint from another solar sys- tem,” shares Nathan Roth, lead au- thor on this research and a professor with American University. “The de- tails reveal what it’s made of, and it’s bursting with methanol in a way wejustdon’tusuallyseeincometsin our own solar system.” Using ALMA’s Morita Array (Ata- camaCompactArray-ACA)inChile, the research team observed 3I/- ATLASonmultipledatesinlate2025 as the comet approached the Sun. As sunlight warmed its icy surface, the comet released gas and dust, forming a glowing halo—known asacoma—arounditsnucleus.Byana- lyzingthecompositionofthiscoma, astronomerswereabletoidentify thechemicalfingerprintsofthema- terialmakingupthecometandgain insights into the conditions under which it formed. Theteamfocusedonthefaintsub- millimeter signatures of two mole- cules: methanol (CH ₃ OH), an alco- hol,andhydrogencyanide(HCN),a nitrogen-bearingorganicmolecule commonlyobservedincomets.The ALMAdatarevealthat3I/ATLASis MAY-JUNE2026 ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 32 أﻟﻤﺎ ﺗ ﻜﺘ ﺸﻒوﻓﺮة ﻣ ﺜﺎﻧﻮل ﻏ ﻣﺴﺒﻮﻗﺔ ﻓﻲﻣ ﺬﻧﺐ : ﻘﻠﻢ ﻧﻴ ﻮﻻس ﻟ ا، ﺟﻴﻞ ﻣﺎﻟﻮﺳﻜﻲ ﺎر ﺎرا ﻓ ﺮا ، ﻳﻮ ﺘﺸﻲﻣﺎﺗﺴﻮدا ﻣﺮﺻﺪ أﻟﻤﺎ اﺳـﺘﻄﺎع ﻓﺮﻳﻖ ﻣﻦ ﻋﻠﻤﺎء اﻟﻔﻠـﻚ ﺑﺎﺳـﺘﺨﺪام ﻣﺼﻔﻮﻓﺔ أﺗﺎﻛﺎﻣﺎ اﻟﻜﺒ ة ا ﻠﻴﻤﱰﻳـﺔ وﺗﺤـﺖ ا ﻠﻴﻤﱰﻳﺔ ( أ ﺎ) ﻣﻦ رﺻﺪ ﻛﻤﻴﺔ ﻏ اﻋﺘﻴﺎدﻳﺔ وﻛﺒ ة ﺟﺪاً ﻣﻦ اﻟﺠﺰيء اﻟﻌﻀﻮي ا ﻴﺜﺎﻧﻮل ﰲ ا ﺬﻧﺐ ﺑـ اﻟﻨﺠﻤـﻲ 3I/ATLAS ﻛﺎﺷـﻔ ﺑﺬﻟﻚ ﻋﻦ ﻇﺮوف ﻛﻴﻤﻴﺎﺋﻴﺔ ﺗﺨﺘﻠﻒ ﻋﻤ ﺎ ﻳﻮﺟﺪ ﰲ ﻣﻌﻈﻢ ﻣﺬﻧﺒﺎت ﻧﻈﺎﻣﻨﺎ اﻟ . ﺸﻤﴘـ ﺗ ﻈﻬﺮ ﻫﺬه اﻷرﺻـﺎد أن ا ـﺬﻧﺐ 3I/ATLAS ﻳﺤﺘﻮي ﻋـﲆ ﻛﻤﻴـﺎت ﻣـﻦ ا ﻴﺜـﺎﻧﻮل ﺗﻔـ ﻮق ﺑﺸﻜﻞ ﻣﻠﺤـﻮظ ﺳـﻴﺎﻧﻴﺪ اﻟﻬﻴـﺪروﺟ ﲆ ﻋـ ﺧﻼف ﺟﻤﻴﻊ ا ﺬﻧﺒﺎت اﻟﺘﻲ درﺳـﺖ ﺳـﺎﺑﻘ . ﺎً وﺗﻮﻓﺮ ﻫﺬه اﻟﻨﺘﺎﺋﺞ اﻟﺠﺪﻳـﺪة ﻓﺮﺻـﺔ ﻧـﺎدرة ﻟ ﺪراﺳﺔ ﻛﻴﻤﻴـﺎء اﻷﻧﻈﻤـﺔ اﻟﻜﻮﻛﺒﻴـﺔ ﺧـﺎر ج ﻧﻈﺎﻣﻨﺎ اﻟﺸﻤﴘ . ﻳﻘـﻮل ﻧﺎﺛـﺎن روث ا ﺆﻟـﻒ اﻟﺮﺋﻴ ـ ﺳـﺘﺎذ واﻷ ﴘ ﻟﻬﺬا اﻟﺒﺤﺚ ﰲ اﻟﺠﺎﻣﻌـﺔ اﻷﻣﺮﻳﻜﻴ ـﺔ :» إن رﺻــﺪ ا ـﺬﻧﺐ 3I/ATLAS ﻳﺸﺒﻪ أﺧﺬ ﺑﺼﻤﺔ ﻣﻦ ﻧﻈـﺎم ﺷـ ـ ﻤﴘ آﺧـﺮ ﻓﺎﻟﺘﻔﺎﺻﻴﻞ ﺗﻜﺸﻒ ﻣﻤ ﺎ ﻳﺘﻜـﻮّن وﻫـﻮ ﻏﻨـﻲ ﺑﺎ ﻴﺜﺎﻧﻮل ﺑﻄﺮﻳﻘﺔ ﻻ ﻧﺮاﻫﺎ ﻋﺎدة ﰲ ﻣـﺬﻧﺒﺎت ﻧ ﻈﺎﻣﻨﺎ اﻟﺸﻤـ وﺑﺎ «ﴘـ ﺳـﺘﺨﺪام ﻣﺼـﻔﻮﻓﺔ ) ﻣﻮرﻳﺘﺎ ﻣﺼﻔﻮﻓﺔ أﺗﺎﻛﺎﻣﺎ ا ﺪﻣﺠـﺔ – ACA ( ـــــــــــــــــــــــــــــــــــــ ﰲ ﺗﺸﻴﲇ ﻗﺎم ﻓﺮﻳـﻖ اﻟﺒﺤـﺚ ﺑﺮﺻـﺪ ا ـﺬﻧﺐ 3I/ATLAS ﰲ ﻋﺪة ﺗﻮارﻳﺦ ﺧﻼل أواﺧﺮ ﻋﺎم 2025 ﻣﻊ اﻗﱰاب ا ﺬﻧﺐ ﻣﻦ اﻟﺸـﻤﺲ ﻊ وﻣـ ﺗﺴﺨ ﺿـﻮء اﻟﺸـﻤﺲ ﻟﺴـﻄﺤﻪ اﻟﺠﻠﻴـﺪي أﻃﻠﻖ ا ﺬﻧﺐ ﻏـﺎزات وﻏﺒـﺎر اً ﻣﺸـﻜﻼً ﻫﺎﻟـﺔ ﺔ ﺗ ﻣﺘﻮﻫﺠ ﻌﺮف ﺑﺎﺳﻢ اﻟﺬوأﺑـﺔ ﺣـﻮل ﻧﻮاﺗـﻪ وﻣﻦ ﺧﻼل ﺗﺤﻠﻴﻞ ﺗﺮﻛﻴ ﺐ ﻫﺬه اﻟﺬوأﺑﺔ ﺗﻤﻜـ ﻦ ﻋﻠﻤــ ﺎء اﻟﻔﻠــﻚ ﻣــﻦ ﺗﺤﺪﻳــﺪ " اﻟﺒﺼــﻤﺎت اﻟﻜﻴ " ﻤﻴﺎﺋﻴﺔ ﻟﻠﻤﻮاد ا ﻜﻮﱢ ﻧﺔ ﻟﻠﻤﺬﻧﺐ واﻟﺤﺼﻮل ﻋﲆ رؤى ﺣﻮل اﻟﻈﺮوف اﻟﺘـﻲ ﺗﺸـﻜّﻞ ﻓﻴﻬـﺎ . ـــــــــــــــــــــــــــــــــــــ رﻛّﺰ اﻟﻔﺮﻳﻖ ﻋﲆ اﻹﺷﺎرات اﻟﻀﻌﻴﻔﺔ ﰲ ﻧﻄﺎق ﻣ ــﺎ دون ا ﻠﻴﻤ ــﱰ ﻟﺠــﺰﻳﺌ : ا ﻴﺜ ــﺎﻧﻮل ) CH ₃ OH ( وﻫﻮ ﻛﺤﻮل وﺳﻴﺎﻧﻴﺪ اﻟﻬﻴﺪروﺟ ) HCN ( وﻫﻮ ﺟﺰيء ﻋﻀـﻮي ﻳﺤﺘـﻮي ﻋـﲆ اﻟﻨ ﻴﱰوﺟ وﻳ ﺮﺻﺪ ﻋﺎدة ﰲ ا ﺬﻧﺒﺎت . ﺗﻜﺸـﻒ ﺑﻴﺎﻧـﺎت ﻣﺼــﻔﻮﻓﺔ أ أن ــﺎ ا ـﺬﻧﺐ 3I/ATLAS ﻏﻨـﻲ ﺟـﺪاً ﺑﺎ ﻴﺜـﺎﻧﻮل ﻣﻘﺎرﻧـﺔ ﺑﺴﻴﺎﻧﻴ ﺪ اﻟﻬﻴﺪروﺟ . ﻓﻔﻲ ﺗﺎرﻳﺨ ﻟﻠﺮﺻـﺪ ﻗﺎس اﻟﺒﺎﺣﺜﻮن ﻧﺴـﺐ ا ﻴﺜـﺎﻧﻮل إﱃ ﺳـﻴﺎﻧﻴﺪ اﻟﻬﻴ ـﺪروﺟ ﺑﺤ ـﻮا ﱄ 70 و 120 ﻣــﺎ ﻳﻀــﻊ ـــــــــــــــــــــــــــــــــــــ - ﻣﺎﻳﻮ ﻳﻮﻧﻴﻮ 2 0 2 6