Free Astronomy Magazine March-April 2024 ARABIC VERSION

A ALMA spots the shadow of a molecular outflow from a quasar by ALMA Observatory Nicolás Lira quasar is a compact region powered by a supermassive black hole located in the center of a massive galaxy. They are extremely luminous, with a point- like appearance similar to stars, and are extremely distant from Earth. Owing to their distance and bright- ness, they provide a peek into condi- tions of the early Universe, when it was less than 1 billion years old. A team of researchers led by Assis- tant Professor Dragan Salak at Hokkaido University, Assistant Pro- fessor Takuya Hashimoto at the University of Tsukuba, and Profes- sor Akio Inoue at Waseda Univer- sity, has discovered the first evi- dence of suppression of star forma- tion driven by an outflow of molec- ular gas in a quasar-host galaxy in the early Universe. Their findings, based on observations they made using the Atacama Large Millime- ter/submillimeter Array (ALMA), in Chile, were published in The Astro- physical Journal . Molecular gas is vital to the forma- tion of stars. As the primary fuel of star formation, the ubiquity and high concentrations of molecular gas within a galaxy would lead to a vast number of stars being formed. By ejecting this gas into intergalactic space faster than it could be con- sumed by star formation, molecular outflows effectively suppress the formation of stars in galaxies that host quasars. “Theoretical work suggests that mo- lecular gas outflows play an impor- tant role in the formation and evolution of galaxies from an early age, because they can regulate star formation,” Salak explains. “Quasars are especially energetic sources, so we expected that they may be able ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 36 أﻟﻤﺎ " ﻳ" ﺮﺻﺪﻇﻞ اﻟﺘﺪﻓﻖ ـاﻟ ﻣﻦ ﺠﺰ ﻮازار : ﻘﻠﻢ ﻧﻴ ﻮﻻس ﻟ ا - ﻣﺮﺻﺪ أﻟﻤﺎ - ﻣﺎﺭﺱ ﺃﺑﺮﻳﻞ 2 0 2 4 ـﻮازارات اﻟ ﺎﻃﻖ ﻣﻨ ﻲﻫ ﻣﺪﻣﺠﺔ ﻣﺪﻋﻮﻣﺔ ﺑﺜﻘﺐ أﺳﻮد ﻫﺎﺋﻞ ﻳﻮﺟـﺪ ﰲ ﻣﺮﻛـﺰ ﻣﺠـﺮة ﺿﺨﻤﺔ وﻫﻲ أﺟﺮام ﻣﻀـﻴﺌﺔ ﻟﻠﻐﺎﻳـﺔ وﻟﻬـﺎ ﻣﻈﻬﺮ ﻳﺸﺒﻪ اﻟﻨﺠﻮم وﻫﻲ ﺑﻌﻴﺪة ﺟـﺪ اً ﻋـﻦ اﻷرض اً ﻧﻈﺮ و ﻟﺒﻌﺪﻫ ﺎ وﺳﻄﻮﻋﻬ ﺎ ﻮﻓﺮ ﺗ ﺎ ﻓﺈﻧﻬ ﻧ ﻈﺮة ﺧﺎﻃﻔﺔ ﻋﲆ ﻇـﺮوف اﻟﻜـﻮن ا ﺒﻜـﺮ ﻋﻨﺪﻣﺎ ﻛﺎن ﻋﻤﺮه أﻗﻞ ﻣﻦ ﻣﻠﻴﺎر ﺳﻨﺔ . اﻛﺘﺸــﻒ ﻓﺮﻳــﻖ ﻣــﻦ اﻟﺒــﺎﺣﺜ ﺑﻘﻴــﺎدة اﻟﱪ وﻓﻴﺴﻮر ا ﺴﺎﻋﺪ دراﺟـﺎن ﺳـﺎﻻك ﻣـﻦ ﺟﺎﻣﻌﺔ ﻫﻮﻛﺎﻳﺪو، واﻷﺳﺘﺎذ ا ﺴﺎﻋﺪ ﺗ ﺎﻛﻮﻳـﺎ ﻫﺎﺷﻴﻤﻮﺗﻮ ﻣﻦ ﺟﺎﻣﻌﺔ ﺗﺴﻮﻛﻮﺑﺎ واﻷ ﺳـﺘﺎذ أﻛﻴﻮ إﻳﻨﻮي ﻣﻦ ﺟﺎﻣﻌـﺔ واﺳـﻴﺪا أول دﻟﻴـﻞ ﻋﲆ ﻗﻤﻊ ﺗﻜﻮﻳﻦ اﻟﻨﺠﻮم ﺑﺴﺒﺐ ﺗﺪﻓﻖ ﻏـﺎز ا ﻮاد اﻟﺠﺰﻳﺌﻴﺔ إﱃ اﻟﺨﺎر ج ﰲ ﻣﺠﺮة ﻣﻀﻴﻔﺔ ﻟﻠﻜﻮازار ﰲ ﺑﺪاﻳﺔ اﻟﻜﻮن . اﻟﻨﺘﺎﺋﺞ اﻟﺘﻲ ﺗﻮﺻﻠﻮا إﻟﻴﻬﺎ ﺑﻨﺎء ﻋﲆ اﻷرﺻﺎد اﻟﺘﻲ ﻗﺎﻣﻮا ﺑﻬﺎ ﺑﺎﺳﺘﺨﺪام ﻣﺼﻔﻮﻓﺔ اﺗﺎﻛﺎﻣﺎ ا ﻠﻴﻤﱰﻳﺔ / ﺗﺤﺖ ا ﻠﻴﻤﱰﻳﺔ اﻟﻜﺒ ة أ ـﺎ ) ﰲ ( وﻗﺪ ﺗﺸﻴﲇ ﺗﻢ ﻧﴩﻫﺎ ﰲ ا ﺠﻠـﺔ اﻟﻔﻴﺰﻳﺎﺋﻴـﺔ اﻟﻔﻠﻜﻴﺔ . ﻳﻠﻌﺐ اﻟﻐﺎز اﻟﺠﺰﻳﺌﻲ دور اً ﰲ ﺎً ﺣﻴﻮﻳ ﺗﻜﻮﻳﻦ اﻟﻨﺠﻮم ﺑﺎﻋﺘﺒـﺎ ره اﻟﻮﻗـﻮد اﻷﺳـﺎﳼ ﻟﺘﻜ ـﻮﻳﻦ اﻟﻨﺠ ـﻮم ﻓ ـﺈن اﻟﻮﺟــﻮد ا ﻄﻠــﻖ واﻟﱰﻛﻴﺰات اﻟﻌﺎﻟﻴﺔ ﻟﻠﻐـﺎز اﻟﺠﺰﻳﺌـﻲ داﺧـﻞ ا ﺠﺮة ﺳﻴﺆدي إﱃ ﺗﻜـﻮﻳﻦ ﻋـﺪد ﻛ ﺒـ ﻣـﻦ اﻟﻨﺠﻮم ﻋـﻦ ﻃﺮﻳـﻖ ﻗـﺬف ﻫـﺬا اﻟﻐـﺎز إﱃ اﻟ ﻔﻀﺎء ﺑـ ا ﺠـﺮات ﺑﺸـﻜﻞ أﴎع ﻣﻤـﺎ ﻳﻤﻜﻦ أن ﺗ ﺴﺘﻬﻠﻜﻪ ﻋﻤﻠﻴﺔ ﺗﻜﻮﻳﻦ اﻟﻨﺠﻮم ﺗﻤﻨـﻊ اﻟﺘـﺪﻓﻘﺎت اﻟﺠﺰﻳﺌﻴـﺔ ﺑﺸـﻜﻞ ﻓﻌـﺎل ﺗﻜﻮﻳﻦ اﻟﻨﺠﻮم ﰲ ا ﺠﺮات اﻟﺘـﻲ ﺗﺴﺘﻀـﻴﻒ اﻟﻜﻮازارات . ﻳﻮﺿﺢ ﺳﺎﻻك :» ﻳﺸ اﻟﻌﻤﻞ اﻟﻨﻈﺮي إﱃ أن ﺗﺪﻓﻘﺎت اﻟﻐﺎز اﻟﺠﺰﻳﺌـﻲ إﱃ اﻟﺨـﺎرج ﺗﻠﻌـﺐ دورًا ﻣﻬﻤًﺎ ﰲ ﺗﻜﻮﻳﻦ وﺗﻄﻮر ا ﺠـﺮات ﻣﻨـﺬ ﺳﻦ ﻣﺒﻜﺮة، ﻷﻧﻬﺎ ﻳﻤﻜـﻦ أن ﺗـﻨﻈﻢ ﻋﻤﻠﻴـﺔ ﺗﻜﻮﻳﻦ اﻟﻨﺠﻮم «" . ﺗﻌﺪ اﻟﻜﻮازارات ﻣﺼـﺎدر ﻃﺎﻗﺔ ، ﻟﺬﻟﻚ ﺗﻮﻗﻌﻨﺎ أﻧﻬﺎ ﻗﺪ ﺗﻜـﻮن ﻗـﺎدرة ﻋﲆ ﺗﻮﻟﻴﺪ ﺗﺪﻓﻘﺎت ﺧﺎرﺟﻴﺔ ﻗﻮﻳﺔ .