Free Astronomy Magazine July-August 2026 ARABIC VERSION

T the semi-heavy water contentof hisartist’simpressioncompares theinterstellarcomet3I/ATLAS(left) andEarth(right).Insetsillustratethe relative abundance of deuterated water(HDO)molecules,showingthat 3I/ATLAScontainsover30timesmore HDOthanisfoundinEarth’soceans. This elevated ratio suggests the comet formed in an extremely cold environment,verydifferentfromthe conditionsthatshapedourSolarSys- tem. [NSF/AUI/NSF NRAO/M.Weiss] 3I/ATLAS formedin a far colder world than our own byALMAObservatory Bárbara Ferreira ewobservationsfromtheAt- acama Large Millimeter/sub- millimeter Array (ALMA) have yieldedthefirst-evermeasurement of deuterated water — also known as semi-heavy water — in an inter- stellar object. The discovery reveals that the interstellar comet 3I/ATLAS contains at least 30 times the pro- portion of semi-heavy water found in comets from our own Solar Sys- tem,providingadirectchemical window into the frigid conditions underwhichitshomestarsystem formed. TheresearchwasledbyPhDstudent LuisE.SalazarManzanoattheUni- versityofMichigan,workingwith assistant professor Teresa Paneque- Carreño, who served as Principal In- vestigator of the ALMA Director’s Discretionary Time program that made these observations possible. Thedatawereobtainedwith ALMA’s Atacama Compact Array (ACA) just six days after 3I/ATLAS reacheditsclosestpointtotheSun — a narrow observing windowmade possible by ALMA’s unique abilitytopointtowardthesolardi- rection, unlike most optical tele- scopes. “Our new observations show thattheconditionsthatledtotheforma - tion of our Solar System are much differentfromhowplanetarysys- tems evolved in different parts of our Galaxy,” said Salazar Manzano. Comets are often nicknamed dirty snowballs,inpartbecauseoftheir JULY-AUGUST2026 N اﻟﻤﺬﻧﺐ 3I/ATLAS ﺗﺸ ﻞﻓﻲ ﻋﺎﻟﻢﻣﺘ ﻤﺪ : ﻘﻠﻢ ﺎر ﺮا ﻓ ﺮا ﻣﺮﺻﺪ أﻟﻤﺎ اﻟﻔﻠﻜﻲ 4 أﺳـﻔﺮ أرﺻــﺎد ﺟﺪﻳــﺪة أﺟﺮاﻫــﺎ ﻣﺮﺻــﺪ ﻣﺼﻔﻮﻓﺔ أﺗﺎﻛﺎﻣﺎ ا ﻠﻴﻤﱰﻳﺔ / دون ا ﻠﻴﻤﱰﻳـﺔ اﻟ أ ﺎ) ﻜﺒ ة ( ﻋـﻦ أول ﻗﻴـﺎس ﻋـﲆ اﻹﻃـﻼق ﻟﻠﻤﺎء ا ُﺜﻘﱠ ﻞ ﺑﺎﻟﺪﻳﻮﺗ ﻳﻮم ا ﻌﺮوف أﻳﻀﺎً ﺑﺎﺳﻢ ا ﺎء ﺷﺒﻪ اﻟﺜﻘﻴﻞ ﰲ ﺟﺮم ﺑ ﻧﺠﻤﻲ . وﻳﻜﺸﻒ ﻫ ـﺬا اﻻﻛﺘﺸ ـﺎف أن ا ـﺬﻧﺐ ﺑ ـ اﻟﻨﺠﻤ ـﻲ 3I/ATLAS ﻳﺤﺘﻮي ﻋﲆ ﻧﺴﺒﺔ ﻣﻦ ا ﺎء ﺷﺒﻪ اﻟﺜﻘﻴﻞ ﺗﻌﺎدل ﻣﺎ ﻻ ﻳﻘﻞ ﻋﻦ 30 ﺿﻌﻒ اﻟﻨﺴﺒﺔ ا ﻮﺟﻮدة ﰲ ﻣﺬﻧﺒﺎت ﻧ ﻤﴘـ ﻈﺎﻣﻨﺎ اﻟﺸـ ﻣﻤـﺎ ﻳﻮﻓﺮ ﻧﺎﻓﺬة ﻛﻴﻤﻴﺎﺋﻴﺔ ﻣﺒﺎﴍة ﻋـﲆ اﻟﻈـﺮوف ﺷﺪﻳﺪة اﻟﱪودة اﻟﺘـﻲ ﺗﺸـﻜ ﻞ ﻓﻴﻬـﺎ ﻧﻈﺎﻣـﻪ اﻟﻨﺠﻤـﻲ اﻷﺻـﲇ . ﻗـﺎد ﻫـﺬا اﻟﺒﺤـﺚ ﻃﺎﻟـﺐ اﻟﺪﻛﺘﻮراه ﻟﻮﻳﺲ إي ﺳـ . ﺎﻻزار ﻣـﺎﻧﺰاﻧﻮ ﻣـﻦ ﺟﺎﻣﻌﺔ ﻣﻴﺸـﻴﻐﺎن ﺑﺎﻟﺘﻌـﺎون ﻣـﻊ اﻷﺳـﺘﺎذة ا ﺴﺎﻋﺪة ﺗ ﻳﺰا ﺑﺎﻧﻴﻜﻲ ﻛﺎرﻳﻨﻴﻮ - اﻟﺘﻲ ﺷﻐﻠﺖ ﻣﻨﺼﺐ اﻟﺒﺎﺣﺜـﺔ اﻟﺮﺋﻴﺴـﺔ ﻟﱪﻧـﺎﻣﺞ اﻟﻮﻗـﺖ اﻟﺘﻘﺪﻳﺮي ﺪﻳﺮ ﻣﺮﺻﺪ ا ﺎ اﻟﻔﻠﻜﻲ واﻟ ﺬي أﺗﺎح ﺗﻨﻔﻴﺬ ﻫـﺬه اﻷﺻـﺎد وﻗـﺪ ﺟ ﻤﻌـﺖ اﻟﺒﻴﺎﻧـﺎت ﺑﺎﺳﺘﺨﺪام ﻣﺼﻔﻮﻓﺔ أﺗﺎﻛﺎﻣﺎ ا ﺪﻣﺠﺔ ) ACA ( اﻟﺘﺎﺑﻌﺔ ﺮﺻﺪ أ ﺎ اﻟﻔﻠﻜﻲ ﺑﻌﺪ ﺳﺘﺔ أﻳﺎم ﻓﻘﻂ ﻣـﻦ وﺻـﻮل ا ـﺬﻧﺐ 3I/ATLAS إﱃ أﻗــﺮب ﻧﻘﻄﺔ ﻟﻪ ﻣـﻦ اﻟﺸـﻤﺲ وﻫـﻲ ﻧﺎﻓـﺬة رﺻـﺪ ﺿﻴﻘﺔ أﺗﻴﺤﺖ ﺑﻔﻀﻞ اﻟﻘﺪرة اﻟﻔﺮﻳﺪة ﺮﺻـﺪ أ ﺎ ﻋﲆ اﻟﺘﻮﺟﻴﻪ ﻧﺤـﻮ اﺗﺠـﺎه اﻟﺸـﻤﺲ ﻋـﲆ ﻋﻜﺲ ﻣﻌﻈﻢ اﻟﺘﻠﺴﻜﻮﺑﺎت اﻟﺒ . ﴫﻳﺔ ـ وﻗـﺎل ﺳـﺎﻻزار ﻣـﺎﻧﺰاﻧﻮ ﺗ» : ﻈﻬـﺮ أرﺻـﺎدﻧﺎ اﻟﺠﺪﻳـﺪة أن ا ﻟﻈــﺮوف اﻟﺘـﻲ أدت إﱃ ﺗﺸـﻜ ﻞ ﻧﻈﺎﻣﻨﺎ اﻟﺸﻤﴘ ﺗﺨﺘﻠﻒ ﻛﺜ اً ﻋـﻦ اﻟﻜﻴﻔﻴـﺔ اﻟﺘﻲ ﺗﻄﻮرت ﺑﻬﺎ اﻷﻧﻈﻤﺔ ا ﻟﻜﻮﻛﺒﻴﺔ ﰲ أﺟـﺰاء أﺧﺮى ﻣﻦ ﻣﺠﺮﺗﻨﺎ «. ﻏﺎﻟﺒﺎً ﻣﺎ ﺗُﻠﻘﱠ ﺐ ا ـﺬﻧﺒﺎت ــ » ﺑـ ﻛﺮات اﻟﺜﻠﺞ ا ﻠﻮﺛﺔ « وﻳﺮﺟﻊ ذﻟﻚ ﺟﺰﺋﻴ ﺎً إﱃ ﻣﺤﺘﻮاﻫﺎ ا ﺮﺗﻔﻊ ﻣﻦ ا ﺎء وﻫـﻮ ﻣـﺎء ﻳﺤﻤـﻞ ﺳﺠﻼت ﻛﻴﻤﻴﺎﺋﻴﺔ ﻣﺘﺠﻤﺪة ﻟﻠ ﺒﻴﺌﺔ اﻟﺘﻲ ﺗﻜﻮّن ﻓﻴﻬـﺎ ا ـﺬﻧﺐ وﺑﺎﻹﺿـﺎﻓﺔ إﱃ ا ــﺎء اﻟﻌــﺎدي ـــــــــــــــــــــــــــــــــــــ ﻘـــﺎرن ﻫـــ ﺬا اﻟﺮﺳـــﻢ اﻟﺘﺨ ﻠـــﻲﻣﺤﺘـــﻮى اﻟﻤـــﺎء ﺷـــــــــ ﮫ اﻟﺜﻘﻴـــــــــﻞ ﻓـــــــــﻲ اﻟﻤـــــــــﺬﻧﺐ ﺑـــــــــ اﻟﻨ ﻤــــــــــﻲ 3I/ATLAS ( ﻤــــــ ) (. ﺴـــــــﺎر ) واﻷرض ﺗﻮﺿـــــــﺢ ــــﺔ اﻹﻃــــﺎرات اﻟﺪاﺧﻠ اﻟــــﻮﻓﺮة اﻟﻨﺴــــﺒ ﺔ ﻟــــ ـ ﺠﺰ ﺌﺎت اﻟﻤــــــــــــــــﺎء اﻟﻤ ﺜﻘــــــــــــــــﻞ ﺎﻟــــــــــــــــﺪﻳﻮﺗ ﻮم ﻣ ﺒ ﻨــــــــــــــــﺔً أن 3I/ATLAS ﻳﺤﺘــﻮيﻋﻠــﻰ أﻛــ ﻣــﻦ 30 ﺿـــﻌﻒ ﻣـــــــﻦ HDO اﻟﻤﻮﺟـــــــﻮد ﻓـــــــﻲﻣﺤ ﻄـــــــﺎت اﻷرض . و ﺗﺸ ﻫﺬﻩ اﻟﻨﺴ ﺔ اﻟﻤﺮ ﻔﻌﺔ إﻟﻰأن اﻟﻤﺬﻧﺐ ﻗــﺪ ﺗﺸـــ ﻞ ﻓــﻲ ﺑﻴﺌـــﺔ ﺷــﺪ ﺪة اﻟـــ ودة ﻣﺨﺘﻠﻔـــﺔ ﺷ ﻠﺖ ﻧﻈﺎﻣﻨﺎ اﻟﺸﻤﺴﻲ ﻋﻦ اﻟﻈﺮوف اﻟ . [NSF/AUI/NSF NRAO/M.Weiss] - ﻳﻮﻟﻴﻮ ﺃﻏﺴﻄﺲ 2 0 2 6