Free Astronomy Magazine March-April 2025 ARABIC VERSION

ing in the same way. “With more matter around the stars, the accre- tion lasts for a longer time,” said Sabbi. “The disks take ten times longer to disappear. This has impli- cations for how you form a planet, and the type of system architecture that you can have in these different environments. This is so exciting.”  ﻣ ﻦ اﻟﻬﻴﺪروﺟ واﻟﻬﻴﻠﻴـﻮم ﰲ اﻟﻐـﺎز ﻟﻜـﻦ ﻋﻨﻘﻮد اﻟﻨﺠﻮم اﻟﻀﺨﻢ NGC 346 ﻳ ﺤﺘـﻮي ﻓﻘﻂ ﻋﲆ ﺣﻮاﱄ ﻋﴩة ﰲ ا ﺎﺋﺔ ﻣﻦ اﻟﻌﻨﺎﴏ اﻟﺜﻘﻴﻠـﺔ ا ﻮﺟـﻮدة ﰲ اﻟﱰﻛﻴـﺐ اﻟﻜﻴﻤﻴـﺎﺋﻲ ﻠﻟ ﺸــﻤﺲ رﺑﻤــﺎ ﻳﺴ ـﺘﻐﺮق ﻧﺠــﻢ ﰲ ﻫ ـﺬه ا ﺠﻤﻮﻋـﺔ وﻗﺘًـﺎ أﻃــﻮل ﻟﺘﺸــﺘﻴﺖ ﻗﺮﺻـﻪ واﻻﺣﺘﻤﺎل اﻟﺜﺎﻧﻲ ﻫﻮ أﻧﻪ ﻟﻜﻲ ﻳﺘﺸﻜﻞ ﻧﺠـﻢ ﺷﺒﻴﻪ ﺑﺎﻟﺸﻤﺲ ﻋﻨﺪﻣﺎ ﻳﻜـﻮن ﻫﻨـﺎك ﻋـﺪد ﻗﻠﻴﻞ ﻣﻦ اﻟﻌﻨﺎﴏ اﻟﺜﻘﻴﻠﺔ، ﻓﻴﺠـﺐ أن ﻳﺒـﺪأ ﻗﻠﻴﻞ ﻣﻦ اﻟﻌﻨﺎﴏ اﻟﺜﻘﻴﻠﺔ ﻓﻴﺠﺐ أن ﻳﺒﺪأ ﻣﻦ ﺳﺤﺎﺑﺔ ﻏﺎزﻳﺔ أﻛﱪ . ﺳﺘﻨﺘ ﺞ ﺳـﺤﺎﺑﺔ اﻟﻐـﺎز اﻷﻛﱪ ﻗﺮﺻﺎً أﻛﱪ وﺑﺎﻟﺘﺎﱄ ﻳﻮﺟﺪ ا ﺰﻳـﺪ ﻣـﻦ اﻟﻜﺘﻠﺔ ﰲ اﻟﻘﺮص وﺑﺎﻟﺘ ﺎﱄ ﺳﻴﺴﺘﻐﺮق ﺗﻔﺠ اﻟﻘﺮص وﻗﺘًﺎ أﻃﻮل ﺣﺘﻰ ﻟـﻮ ﻛـﺎن ﺿـﻐﻂ اﻹﺷﻌﺎع ﻳﻌﻤﻞ ﺑﻨﻔﺲ اﻟﻄﺮﻳﻘﺔ . ﻗﺎل ﺳﺎﺑّﻲ " : ﻣﻊ و ﺟﻮد ا ﺰﻳﺪ ﻣﻦ ا ﺎدة ﺣﻮل اﻟﻨﺠ ـﻮم ﻳﺴ ـﺘﻤﺮ اﻟ ـﱰاﻛﻢ ﻟﻔ ـﱰة أﻃ ـﻮل ﺗﺴﺘﻐﺮق اﻷﻗﺮاص وﻗﺘًﺎ أﻃﻮل ﺑﻌﴩ ﻣـﺮات ﺗﺴﺘﻐﺮق ﺗﻠﻚ اﻷﻗﺮاص ﻓﱰة زﻣﻨﻴـﺔ أﻃـﻮل ﺑﻌﴩ ﻣﺮات ﻟﺘﺨﺘﻔﻲ . إن ﻫ ﺬا ﻟﻪ آﺛﺎر ﻋﻤﻴﻘﺔ ﻋﲆ ﻛﻴﻔﻴـﺔ ﺗﻜـﻮﻳﻦ اﻟ ﻜﻮﻛﺐ وﻧﻮع ﺑﻨﻴﺔ اﻟﻨﻈﺎم اﻟـﺬي ﻳﻤﻜـﻦ أن ﻜﻮن ﻳ اً ﻣﻮﺟـﻮد ﰲ ﻫـﺬه اﻟﺒﻴﺌـﺎت ا ﺨﺘﻠﻔـﺔ و ﻋﲆ ﻧﻮع ﺑﻨﻴﺔ اﻟﻨﻈﺎم اﻟﻜﻮﻛﺒﻲ وﻫﻮ ﻣﺠﺎل ﺑﺤﺜﻲ ﻳﻮا ﻣﻬـﻢ ﺻـﻞ اﻟﻌﻠﻤـﺎء اﺳﺘﻜﺸـﺎﻓﻪ أ وﻛﺸﻒ ﴎاره ﺑﺸﻜﻞ أﻓﻀﻞ . ﺃﺑﺮﻳﻞ - ﻣﺎﺭﺱ 2 0 2 5 Webb