Free Astronomy Magazine May-June 2024 ARABIC VERSION

R New link found between water and planet formation byESO − BárbaraFerreira esearchers have found water vapour in the disc around a young star ex- actlywhereplanetsmaybe forming. WaterisakeyingredientforlifeonEarth, andisalsothoughttoplayasignificantrole inplanetformation.Yet,untilnow,wehad never been able to map how water is dis- tributedinastable,cooldisc—thetypeof discthatoffersthemostfavourablecondi- tionsforplanetstoformaroundstars.The newfindingsweremadepossiblethanksto the Atacama Large Millimeter/submillime- ter Array (ALMA), in which the European Southern Observatory (ESO) is a partner. “I had never imagined that we could cap- tureanimageofoceansofwatervapourin the same region where a planet is likely forming,” saysStefanoFacchini,anas- tronomer at the University of Milan, Italy, who led the study published in Nature As- tronomy . The observations reveal at least threetimesasmuchwaterasinallof Earth’s the loca Eart “Itis not det solv 450 aut tron Bolo solv allow astronomers to determine the distribution of water in differ- ent regions of the disc. . ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 50 اﻟﻌﺜﻮرﻋﻠﻰرا ﻂﺟﺪ ﺪ ﺑ اﻟﻤ ﺎﻩ ﺗﺸﻜﻴﻞ و اﻟ ﻮﻛﺐ ﻮﻧﻴﻮ ﻳ - ﻣﺎﻳﻮ 2 0 2 4 ﻟﻘــﺪ ـــﺎﺣﺜﻮن ﺑﺨـــﺎراﻟ وﺟـــﺪ اﻟ ﻤـــﺎء ﻓـــﻲ اﻻﻛﺘﺸـــﺎفﺣـــﻮل اﻟـــﻨ ﻢ اﻟﺸـــﺎب وﻫـــﻮ ــﮫ اﻟ ﻮاﻛــﺐ ﺎﻟﻀـــ ﻂ ﻤﻜــﻦ أن ﺗﺘﺸـــ ﻞ ﻓ ــﺎن اﻟــﺬ اﻟﻤ . ﻠﺨــﺺ ـــﺪﻳﻮ ﻫــﺬا اﻟﻔ اﻻﻛﺘﺸﺎف ] ESO [. : ﻘﻠﻢ ﺎر ﺮا ﻓ ﺮا - اﻟﻤﺮﺻﺪ اﻷوروﺑﻲ اﻟـﺠﻨﻮﺑﻲ ﻟﻘﺪ وﺟﺪ اﻟﺒﺎﺣﺜﻮن ﺑﺨﺎر ا ﺎء ﰲ اﻟﻘﺮص ا ﺤﻴﻂ ﺑﻨﺠﻢ ﺷﺎب وﻫﻮ ا ﻜﺎن اﻟﺬي ﻳﻤﻜﻦ أن ﺗﺘﺸﻜﻞ ﻓﻴﻪ اﻟﻜﻮاﻛﺐ . ا ﺎء ﻫﻮ اﻟﻌﻨ ـ ﴫ اﻷﺳﺎﳼ ﻟﻠﺤﻴﺎة ﻋﲆ اﻷرض وﻳُﻌﺘﻘﺪ أﻳﻀ ﺎً أﻧﻪ ﻳﻠﻌﺐ دور ﺎً ﻣﻬﻤ اً ﰲ ﺗﻜﻮﻳﻦ اﻟﻜﻮﻛﺒ ﻮﻣـﻊ ذﻟـﻚ ﺣﺘﻰ اﻵن ﻟﻢ ﻧﺘﻤﻜﻦ ﻗﻂ ﻣﻦ رﺳـﻢ ﺧﺮﻳﻄـﺔ ﻟﻜﻴﻔﻴـﺔ ﺗﻮزﻳﻊ ا ﻴﺎه ﰲ أﺟﺰاء ﻗﺮص ﺑﺎرد ﻏ ﻣﺴﺘﻘﺮ وﻫﻮ ﻧﻮع اﻟﻘﺮص اﻟﺬي ﻳﻮﻓﺮ أﻓﻀﻞ اﻟﻈـﺮوف ا ﻼﺋﻤـﺔ ﻟﺘﺸـﻜﻞ اﻟﻜﻮاﻛﺐ ﺣﻮل اﻟﻨﺠـﻮم . وﻗـﺪ أﺻـﺒﺤﺖ اﻻﻛﺘﺸـﺎﻓﺎت ﺗﻜﺸﻒ اﻻرﺻﺎد ﻋﻦ ﻣﺎ ﻻ ﻳﻘﻞ ﻋﻦ ﺛﻼﺛـﺔ أﺿﻌﺎف ﻛﻤﻴﺔ ا ﻴﺎه ا ﻮﺟـﻮدة ﰲ ﺟﻤﻴـﻊ ﻣﺤﻴﻄ ـﺎت اﻷرضﰲ اﻟﻘ ـﺮص اﻟــﺪاﺧﲇ ﻟﻠﻨﺠﻢ اﻟﺸﺎب اﻟﺸﺒﻴﻪ ﺑﺎﻟﺸﻤﺲ ا ﺴـﻤﻰ HL Tauri واﻟﺬي ﻳﻮﺟﺪ ﻣﺴﺎﻓﺔ ﻋﲆ 450 ﺳﻨﺔ ﺿﻮﺋﻴﺔ ﻣﻦ اﻷرض ﰲ ﻛﻮﻛﺒ . ﺔ اﻟﺜﻮر ﻳﻀﻴ ﻒ ا ﺆﻟﻒ ا ﺸﺎرك ﻟﻴﻮﻧﺎردو ﺗﻴﺴـﺘﻲ ﻋﺎﻟﻢ اﻟﻔﻠﻚ ﰲ ﺟﺎﻣﻌﺔ ﺑﻮﻟﻮﻧﻴـﺎ ﺑﺈﻳﻄﺎﻟﻴـﺎ : " ﻣﻦ اﻟﻼﻓﺖ ﻟﻠﻨﻈﺮ ﺣﻘًﺎ أﻧﻨﺎ ﻻ ﻧﺴـﺘﻄﻴﻊ اﻟﻜﺸﻒ ﻓﺤﺴﺐ ﺑﻞ ﻳﻤﻜﻨﻨﺎ أﻳﻀ ﺎً اﻟﺘﻘﺎط ﻮر ﺗﻔﺼﻴﻠﻴﺔ ﺻ وﻓﺤﺺ ﺑﺨﺎر ا ﺎء ﻣـﻦ ﻋﲆ ﻣﺴﺎﻓﺔ 450 ﺳﻨﺔ ﺿﻮﺋﻴﺔ ﻣﻨﺎ ". اﻟﺠﺪﻳــﺪة ﻣﻤﻜﻨــﺔ ﺑﻔﻀــﻞ ﻣﺼــﻔﻮﻓﺔ أﺗﺎﻛﺎﻣــﺎ ا ﻠﻴﻤﱰﻳﺔ / ﺗﺤﺖ ا ﻠﻴﻤﱰﻳﺔ اﻟﻜﺒ ة ( أ ﺎ) اﻟﺘـﻲ ﻳﻌﻤـ ﻞ ﻓﻴﻬﺎ ا ﺮﺻﺪ اﻟﺠﻨﻮﺑﻲ اﻷوروﺑﻲ ﻛﻤﺮﺻﺪ .ﴍﻳﻚ ﻳﻘﻮل ﺳﺘﻴﻔﺎﻧﻮ ﻓﺎﺗﺸﻴﻨﻲ ﻋﺎﻟﻢ اﻟﻔﻠﻚ ﰲ ﺟﺎﻣﻌﺔ ﻣﻴﻼﻧﻮ ﺑﺈﻳﻄﺎﻟﻴﺎ اﻟﺬي ﻗﺎد اﻟﺪراﺳﺔ ا ﻨﺸﻮرة ﰲ ﻣﺠﻠﺔ ﻧﻴﺘــﴩ أﺳﱰوﻧﻮﻣﻲ :» ﻟﻢ أﺗﺨﻴﻞ أﺑـﺪ اً أﻧﻨـﺎ ﻧﺴـﺘﻄﻴﻊ اﻟﺘﻘـﺎط ﺻﻮرة ﺤﻴﻄﺎت ﻣﻦ ﺑﺨﺎر ا ﺎء ﰲ ﻧﻔﺲ ا ﻨﻄﻘﺔ اﻟﺘـﻲ ﻣﻦ ا ﺤﺘﻤﻞ أن ﻳﺘﺸﻜﻞ ﻓﻴﻬﺎ ﻛﻮﻛﺐ «.