Free Astronomy Magazine September-October 2023 ARABIC VERSION

tending over distances bigger than the entire So-lar System. This finding then motivated as- tronomers to analyse archive obser- vations of the same system made with ALMA, in which ESO is a part- ner. The VLT observations probe the surface of the dusty material around the star, while ALMA can peer deeper into its structure. “With ALMA, it be- came apparent that the spiral arms are undergoing fragmentation, re- sulting in the formation of clumps with masses akin to those of plan- ets,” says Zurlo. Astronomers believe that giant plan- ets form either by ‘core accretion’, when dust grains come together, or by ‘gravitational instability’, when large fragments of the material around a star contract and collapse. While researchers have previously found evidence for the first of these scenarios, support for the latter has been scant. “No one had ever seen a real obser- vation of gravitational instability happening at planetary scales — until now,” says Philipp Weber, a researcher at the University of San- tiago, Chile, who led the study pub- lished in The Astrophysical Journal Letters . “Our group has been searching for signs of how planets form for over ten years, and we couldn’t be more thrilled about this incredible discov- ery,” says team-member Sebastián Pérez from the University of Santi- ago, Chile. ESO instruments will help as- tronomers unveil more details of this captivating planetary system in the making, and ESO’s Extremely Large Telescope (ELT) will play a key role. Currently under construction in Chile’s Atacama Desert, the ELT will be able to observe the system in greater detail than ever before, col- lecting crucial information about it. “The ELT will enable the exploration of the chemical complexity sur- rounding these clumps, helping us find out more about the composi- tion of the material from which potential planets are forming,” con- cludes Weber.     19 ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ ـ ﻋﻠـﻰ اﻟـ ــﺎﻟﻠﻮن اﻷﺻـﻔﺮﺗﻮﺟـﺪ ﺻــﻮرة ﻟﻠـﻨ ﻢ ﺠﺎﻧﺐ اﻷ ﺴـﺮ اﻟﺸـﺎب V960 Mon ــﮫ، ﺗـﻢ اﻟﺘﻘﺎﻃﻬـﺎ ﺎﺳـﺘﺨﺪام أداة ـﺔ اﻟﻤﺤ ﻄـﺔ واﻟﻤــﻮاد اﻟﻤ ﻋـﻦ ﺒﺤـﺚ اﻟ اﻟ ﻮاﻛــﺐ اﻟﻨ ﻤ ﺔ ) ( ﺳﻔﻴ ﻋﺎﻟ ﺔ اﻟﺘ ﺎﻳﻦ اﻟﻄ ﻔﻲ اﻟﻤﺜ ﺘﺔ ﻋﻠﻰ اﻟ ﺘﻠﺴ ﻮب اﻟﻜﺒ ﺟﺪًا اﻟﺘﺎﺑﻊ ﻟﻠﻤﺮﺻﺪ اﻷوروﺑﻲ اﻟـﺠﻨﻮﺑﻲ . ﺼﺒﺢ اﻟﻀﻮء اﻟﻤﻨﻌﻜﺲﻋﻦ اﻟﻤﺎدة اﻟﻐ ﺎر ﺔ اﻟ ﺗــﺪورﺣـــﻮل اﻟـــﻨ ﻢ ﻣﺴـــﺘﻘﻄ ًﺎ - أﻧـــﮫ ﺘـــﺄرﺟﺢ ﻓـــﻲ اﺗﺠـــﺎﻩ ﻣﺤـــﺪد وﻟـــ ﺲ ﺸـــ ﻞ ﻋﺸـــﻮاﺋﻲ ﻣﻤـــﺎ ﻌـــ - ـــﺘﻢ اﻛﺘﺸـــﺎﻓﮫ ﺑﻮاﺳـــﻄﺔ ﺛـــﻢ ( ﺳـــﻔﻴ ) ﻣﻤـــﺎ ﻜﺸـــﻒﻋـــﻦ أذرع ﺣﻠﺰوﻧ ﺔ . ﻤ ﻠﺔ ﺣﻔﺰ ﻫﺬﻩ اﻟﻨﺘﺎﺋﺞ ﻋﻠﻤﺎء اﻟﻔﻠـﻚ ﻋﻠـﻰ ﺗﺤﻠﻴـﻞ اﻻرﺻـﺎد ـﺔ اﻷرﺷـ ﻔ ﺔ ﻟـﻨﻔﺲ اﻟﻨﻈـﺎم اﻟﻤـﺄﺧﻮذ ﺎﺳـﺘﺨﺪام ﻣﺼـﻔﻮﻓﺔ أﺗﺎ ﺎﻣـﺎ اﻟﻜﺒـ ة اﻟﻤﻠ ﻤ ﺗﺤـﺖ / اﻟﻤﻠ ﻤ ﺔ ( أﻟﻤﺎ ) واﻟ ﻌﺪ اﻟﻤﺮﺻﺪ اﻷوروﺑﻲ ا ﻨﻮﺑﻲﺷﺮ ﺎً ﻓﻴﻬﺎ و ﻤﻜﻦ رؤ ﺔ ﻧﺘﺎﺋﺞ ﻫﺬا اﻟﺘﺤﻠﻴﻞ ﻋﻠﻰ اﻟ ـ ﺠﺎﻧﺐ اﻷ ﻤﻦ ﺎﻟﻠﻮن اﻷزرق . ﺗﺴﻤﺢ اﻷﻃﻮال اﻟﻤﻮﺟ ﺔ ﻟﻠﻀﻮء اﻟ ﻠﺘﻘﻄﻬﺎ ﻣﺮﺻﺪ أﻟﻤﺎ ـﺎﻻﺧ اق ﺸـ ﻞ أﻋﻤـﻖ ﻓـﻲ اﻟﻤـﻮاد اﻟﻤﺪار ـﺔ ﻣﻤـﺎ ﻜﺸـﻒﻋـﻦ أن اﻷذرع اﻟـ ـ ﺤﻠﺰوﻧ ﺔ ﺗﺘﻔﺘـﺖ وﺗﺸـ ﻞ ﻛـﺘﻼً ﻣﻤﺎﺛﻠـﺔ ﻟﻜﺘﻠـﺔ اﻟ ﻮاﻛـﺐ . ﻤﻜﻦ أن ﺗﻨ ﻤﺶﻫﺬﻩ اﻟﻜﺘﻞ وﺗﻨﻬﺎر ﻋ ﻋﻤﻠ ﺔ ﺗُﻌﺮف ﺎﺳﻢ " ﻋﺪم اﺳﺘﻘﺮارا ـﻟ " ﺠﺎذﺑ ﺔ ﻟﺘﺸ ﻞ ﻮاﻛﺐ ﻋﻤﻼﻗﺔ . [ESO/ALMA (ESO/NAOJ/NRAO] ﻣﻦ اﻷذرع اﻟﺤﻠﺰوﻧﻴﺔ ا ﻌﻘﺪة ا ﻤﺘـﺪة ﻋـﲆ ﻣﺴﺎﻓﺎت أﻛﱪ ﻣﻦ اﻟﻨﻈﺎم اﻟﺸﻤﴘ ﺑﺄﻛﻤﻠﻪ . وﻗﺪ ﺣﻔﺰ ﻫﺬا اﻻﻛﺘﺸﺎف ﻋﻠﻤﺎء اﻟﻔﻠﻚ ﻋـﲆ ﺗﺤﻠﻴﻞ اﻷرﺻﺎد اﻷرﺷـﻴﻔﻴﺔ ﻟـﻨﻔﺲ اﻟﻨﻈـﺎم اﻟﺬي ﺗﻢ إﺟﺮاؤه ﺑﺎﺳﺘﺨﺪام ﻣﺮﺻﺪ أ ﺎ واﻟﺬي ﻳﻌﺪ ا ﺮﺻﺪ اﻷوروﺑﻲ . ﴍﻳﻜًﺎ ﻓﻴﻪ ﺗﺴﺘﻜﺸﻒ ﻋﻤﻠﻴﺎت رﺻﺪ اﻟﺘﻠﺴﻜﻮب اﻟﻜﺒـ ﺟﺪاً ﺳﻄﺢ ا ﺎدة ا ﻐـﱪة ا ﺤﻴﻄـﺔ ﺑـﺎﻟﻨﺠﻢ ﺑﻴﻨﻤﺎ ﻳﻤﻜﻦ ﺮﺻﺪ أ ـﺎ ﺘﻌﻤـ ﻳ أن ﻖ أﻛﺜـﺮ ﰲ ، ﺑﻨﻴﺘﻪ ﻳﻘﻮل زورﻟﻮ " : ﺑﻮاﺳﻄﺔ ﻣﺮﺻـﺪ أ ـﺎ أﺻﺒﺢ ﻣـﻦ اﻟﻮاﺿـﺢ أ ن اﻷذرع اﻟﺤﻠﺰوﻧﻴـﺔ ﺗﺘﻌﺮض ﻟﻠﺘﺸﻈﻲ ﻣﻤﺎ ﻳﺆدي إﱃ ﺗﻜﻮﻳﻦ ﻛﺘﻞ ﻣﺸﺎﺑﻬﺔ ﻟﻜﺘﻠﺔ اﻟﻜﻮاﻛـﺐ ." ﻳﻌﺘﻘـﺪ ﻋﻠﻤـﺎء اﻟﻔﻠﻚ أن اﻟﻜﻮاﻛـﺐ اﻟﻌﻤﻼﻗـﺔ ﺗﺘﺸـﻜﻞ إﻣـﺎ ﺑﺘﻀﺨﻢ ﻃﺮﻳﻖ اﻟﻠﺐ ﻋﻨـﺪﻣﺎ ﺗـﱰاﻛﻢ ﺣﺒﻴﺒـﺎت اﻟﻐﺒـﺎر ﻋـﻦ ﺑﻌﻀـﻬﺎ او ﻋـﻦ ﻃﺮﻳــﻖ » ﻋــﺪم اﺳـﺘﻘﺮار اﻟﺠﺎذﺑﻴﺔ « ، ﻋﻨﺪﻣﺎ ﺗﻨﻜﻤﺶﺷﻈﺎﻳﺎ ﻛﺒ ة ﻣ ﻦ ا ﺎدة ا ﺤﻴﻄﺔ ﺑﺎﻟﻨﺠﻢ وﺗﻨﻬﺎر وﺑﻴﻨﻤﺎ وﺟـﺪ اﻟﺒــﺎﺣﺜﻮن ﺳــﺎﺑﻘ ﺎً أدﻟــﺔ ﻋــﲆ أول ﻫــﺬه اﻟﺴـﻴﻨﺎرﻳﻮﻫﺎت إﻻ أن دﻋ ـﻢ اﻷﺧــ ﻛ ـﺎن ، ﺿﺌﻴﻼً ﻳﻘﻮل ﻓﻴﻠﻴﺐ وﻳﱪ اﻟﺒﺎﺣﺚ ﰲ ﺟﺎﻣﻌﺔ ﺳﺎﻧﺘﻴﺎﺟﻮ اﻟﺬي ﻗﺎد اﻟﺪراﺳﺔ اﻟﺘﻲ ﻧُﺸـ ﺮت ـ ﰲ ﻣﺠﻠﺔ رﺳـﺎﺋﻞ اﻟﻔﻴﺰﻳـﺎء اﻟﻔﻠﻜﻴـﺔ " : ﻟـﻢ ﻳﺴﺒﻖ ﻷﺣﺪ أن ﺷﺎﻫﺪ رﺻﺪ اً ﺎً ﻴـ ﺣﻘﻴﻘ ﻟﻌـﺪم اﺳﺘﻘﺮار اﻟﺠﺎذﺑﻴﺔ ﻋﲆ ﻣﺴﺘﻮﻳﺎت اﻟﻜﻮاﻛـﺐ ﻳﻘﻮل ﺳﻴﺒﺎﺳﺘﻴﺎن ﺑ ﻳﺰ ﻋﻀﻮ اﻟﻔﺮﻳﻖ ﻣـﻦ ﺟﺎﻣﻌﺔ ﺳﺎﻧﺘﻴﺠﻮ ﰲ ﺗﺸﻴﲇ " : ﻓﺮﻳﻘﻨـﺎ ﻇﻠﺖ ﻳ ﺒﺤﺚ ﻋﻦ ﻋﻼﻣﺎت ﻟ ﻜﻴﻔﻴﺔ ﺗﺸﻜﻞ اﻟﻜﻮ اﻛـﺐ ﻷﻛﺜﺮ ﻣﻦ ﻋﴩﺳﻨﻮات، وﻻ ﻳﻤﻜﻨﻨﺎ ﻷﻛﺜﺮ ﻣـﻦ ﻋـ ـ ﴩ ﺳـﻨﻮات وﻻ ﻳﻤﻜﻨﻨـﺎ أن ﻧﺸــﻌﺮ ﺑﺴ ـﻌﺎدة ﻏ ـﺎﻣﺮة أﻛﺜ ـﺮ إزاء ﻫــﺬا اﻻﻛﺘﺸﺎف ا ﺬﻫﻞ . ﺳﺘﺴﺎﻋﺪ أدوات ا ﺮﺻـﺪ اﻷوروﺑﻲ اﻟﺠﻨﻮﺑﻲ اﻟ ﻌﻠﻤﺎء ﰲ اﻟﻜﺸـﻒ ﻋـﻦ ا ﺰﻳﺪ ﻣـﻦ اﻟﺘﻔﺎﺻـﻴﻞ ﺣـﻮل ﻫـﺬا اﻟﻨﻈـﺎم اﻟﻜﻮﻛﺒﻲ اﻟﺬي ﻳﺘﺸﻜﻞ وﺳﻴﻠﻌﺐ اﻟﺘﻠﺴـﻜﻮب اﻟﻜ ﺒ ﻟﻠﻐﺎﻳﺔ اﻟﺬي ﻳﺠﺮي إﻧﺸﺎؤه ﺣﺎ ﰲ ﻟﻴـﺎً ﺻـﺤﺮاء أﺗﺎﻛﺎﻣــﺎ ﰲ ﺗﺸــﻴﲇ دوراً رﺋﻴﺴـﻴﺎً وﺳﻴﻜﻮن ﻗﺎدر اً ﻋﲆ ﻣﺮاﻗﺒﺔ اﻟﻨﻈﺎم ﺑﺘﻔﺼﻴﻞ أﻛﱪ وﻳﺨﻠﺺ ﻓﻴﱪ إﱃ أن » اﻟﺘﻠﺴﻜﻮب اﻟﻜﺒ ﻟﻠﻐﺎﻳﺔ ﺳـﻴﻤﻜﻦ ﻣـﻦ اﺳﺘﻜﺸـﺎف اﻟﺘﻌ ﻘﻴـﺪ اﻟﻜﻴﻤﻴﺎﺋﻲ ا ﺤﻴﻂ ﺑﻬﺬه اﻟﻜﺘﻞ ﻣﻤﺎ ﻳﺴﺎﻋﺪﻧﺎ ﻋﲆ ﻣﻌﺮﻓﺔ ا ﺰﻳﺪ ﻋﻦ ﺗﺮﻛﻴﺒـﺔ ا ـﺎدة اﻟ ﺘـﻲ ﺗﺘﺸﻜﻞ ﻣﻨﻬﺎ اﻟﻜﻮاﻛﺐ ا ﺤﺘﻤﻠ .ﺔ - ﺳﺒﺘﻤﺒﺮ ﺃﻛﺘﻮﺑﺮ 2 0 2 3