Free Astronomy Magazine September-October 2023 ARABIC VERSION

i\ elements contribute to the compo- sition of gas giants in our Solar Sys- tem, those planets are too cold for the elements to vaporize into the atmosphere making them virtually undetectable. “Truly rare are the times when an exoplanet hundreds of light-years away can teach us something that would otherwise likely be impossi- ble to know about our own Solar System,” said Pelletier. “That is the case with this study.” The abundance of many of these el- ements closely match the abun- dances found in both our Sun and the exoplanet’s host star. This may be no coincidence and provides ad- ditional evidence that gas-giant planets, like Jupiter and Saturn, form in a manner more akin to star formation — coalescing out of the gas and dust of a protoplanetary disk — rather than the gradual ac- cretion and collision of dust, rocks, and planetesimals, which go on to form rocky planets, like Mercury, Venus, and Earth. Another notable result of the study is the first-ever unambiguous detec- tion of vanadium oxide on an exo- planet. “This molecule is of high interest to astronomers because it can have a great impact on the at- mospheric structure of hot giant planets,” says Pelletier. “This mole- cule plays a similar role to ozone being extremely efficient at heating Earth’s upper atmosphere.” Pelletier and his team are motivated to learn more about WASP-76b and other ultra-hot planets. They also hope other researchers will leverage what they learned from this giant exoplanet and apply it to better our understanding of our own Solar System planets and how they came to be. “Available to astronomers across the globe, the International Gemini Observatory continues to deliver new insights that push our understanding of the physical and chemical structure of other worlds. Through such observational pro- grams we are developing a clearer picture of the wider universe and our own place in it,” said NSF Gem- ini Observatory program director Martin Still. “Generations of researchers have used Jupiter, Saturn, Uranus, and Neptune measured abundances for hydrogen and helium to benchmark formation theories of gaseous plan- ets,” says Université de Montréal professor Björn Benneke, a co-au- thor on the study. “Likewise, the measurements of heavier elements such as calcium or magnesium on WASP-76b will help further under- standing the formation of gaseous planets.”     23 ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ إن اﻟ ﻮﻛﺐ WASP-76b ُﻄﻠﻖ ﻋﻠ ﮫ اﺳﻢ اﻟﺬ " اﻟﻤﺸـ ي اﻟـ ـ "ﺤﺎر ﻗﺮ ـﺐ ﺸـ ﻞ ﻛﺒـ ﻣـﻦ ﻧ ﻤـﮫ اﻟـﺬ اﻟﻐــﻼف اﻟــ ﻘـﻮم ﺘﺴـﺨ ـ ﺠﻮي ﻟﻠ ﻮﻛــﺐ إﻟــﻰ درﺟــﺎتﺣــﺮارة ــﺔ ﺟــﺪاُ ﻋﺎﻟ ﺗﺒﺨــﺮاﻟﻌﻨﺎﺻــﺮاﻟﻤ ﻮﻧــﺔ ﻟﻠﺼـﺨﻮر ﻣﺜــﻞ اﻟﻤﻐﻨ ﺴـــﻴﻮم واﻟ ﺎﻟﺴـــﻴﻮم واﻟـــ ـ ﺤﺪ ﺪ ـــﺔ ﺣـــﻮل ﺗﺸــ ﻞ ﻧﻈﺎﻣﻨـــﺎ اﻟﺸﻤﺴـــﻲ ﻣﻤـــﺎ ﻳـــﻮﻓﺮﻧﻈـــﺮة ﺛﺎﻗ . [International Gemini Observatory/ NOIRLab/NSF/AURA/J. da Silva/Spaceengine/M. Zamani ] - ﺳﺒﺘﻤﺒﺮ ﺃﻛﺘﻮﺑﺮ 2 0 2 3 اً ﻧﻈﺮ ﻟـﺪرﺟﺎت اﻟﺤـﺮارة اﻟﻘﺼـﻮى ﻟﻠﻐـﻼف اﻟﺠﻮي ﻟﻠﻜﻮﻛﺐ WASP-76 ﻓﺈن اﻟﻌﻨـﺎﴏ اﻟﺘﻲ اﻛﺘﺸﻔﻬﺎ اﻟﺒـﺎﺣﺜﻮن واﻟﺘـﻲ ﻋـﺎدة ﻣـﺎ ﺗﺸﻜﻞ ﺻﺨﻮر اً ﻫﻨﺎ ﻋﲆ اﻷرض ﺗﺘﺒﺨـﺮ ﺑـﺪﻻً ﻣﻦ ذﻟﻚ وﺑﺎﻟﺘﺎﱄ ﺗﻮﺟﺪ ﰲ اﻟﻐـ ﻼف اﻟﺠـﻮي ﰲ أﺷــﻜﺎﻟﻬﺎ اﻟﻐﺎزﻳ ـﺔ وﺑﻴﻨﻤ ـﺎ ﺗﺴـﺎﻫﻢ ﻫ ـﺬه اﻟﻌﻨﺎﴏﰲ ﺗﻜﻮﻳﻦ اﻟﻜﻮاﻛﺐ اﻟ ﻐﺎزﻳﺔ اﻟﻌﻤﻼﻗﺔ ﰲ ﻧﻈﺎﻣﻨﺎ اﻟﺸﻤﴘ ﻓﺈن ﺗﻠﻚ اﻟﻜﻮاﻛﺐ ﺑـﺎردة اً ﺟﺪ ﺑﺤﻴـﺚ ﻻ ﺗﺘﺒﺨـﺮ اﻟﻌﻨـﺎﴏ ﰲ اﻟﻐـﻼف اﻟﺠﻮي ﻣﻤﺎ ﻳﺠﻌﻠﻬﺎ ﻏـ ﻗﺎﺑﻠـﺔ ﻟﻼﻛﺘﺸـﺎف .ﺎً ﺗﻘﺮﻳﺒ إن وﻓﺮة اﻟﻌﺪﻳﺪ ﻣﻦ ﻫـﺬه اﻟﻌﻨـﺎﴏ ﺗﺘﻄﺎﺑﻖ ﺑﺸﻜﻞ وﺛﻴﻖ ﻣﻊ اﻟﻮﻓﺮة ا ﻮﺟـﻮدة ﰲ ﻛﻞ ﻣﻦ اﻟﺸﻤﺲ واﻟـﻨﺠﻢ ا ﻀـﻴﻒ ﻟﻠﻜﻮﻛـﺐ اﻟﻨﺠﻤﻲ ﻗﺪ ﻻ ﻳﻜﻮن ﻫﺬا ﻣﻦ ﻗﺒﻴـﻞ اﻟﺼـﺪﻓﺔ وﻳﻘﺪم دﻟﻴﻼ ًإﺿﺎﻓﻴ ﺎً ﻋﲆ أن اﻟﻜﻮاﻛﺐ اﻟﻐﺎزﻳﺔ اﻟﻌﻤﻼﻗﺔ ﻣﺜﻞ ﻛﻮﻛﺐ ا ﺸﱰي وزﺣﻞ ﺗﺘﺸﻜ ﻞ ﺑﻄﺮﻳﻘـﺔ أﻗـﺮب إﱃ ﺗﻜـﻮﻳﻦ اﻟﻨﺠـﻮم ﺣﻴـﺚ ﺗﺘﺠﻤﻊ ﻣﻦ اﻟﻐﺎز واﻟﻐﺒﺎر ﰲ ﻗـﺮص ﻛـﻮﻛﺒﻲ ــ ـــ أوﱄ ﺑﺪﻻً ﻣﻦ اﻟﱰاﻛﻢ اﻟﺘﺪرﻳﺠﻲ واﻻﺻـﻄﺪام . اﻟﻐﺒﺎر واﻟﺼﺨﻮر واﻟﻜﻮاﻛﺐ اﻟﺼﻐ ة واﻟﺘـﻲ ﺗﺸـﻜﻞ اﻟﻜﻮاﻛـﺐ اﻟ ﺼـﺨﺮﻳﺔ ﻣﺜـﻞ ﻋﻄـﺎرد واﻟﺰﻫــﺮة واﻷرض وﻣ ـﻦ اﻟﻨﺘ ـﺎﺋﺞ اﻟﺒ ـﺎرزة اﻷﺧﺮى ﻟﻠﺪراﺳﺔ ﻫـﻮ اﻻﻛﺘﺸـﺎف اﻷول ﻋـﲆ اﻹﻃـﻼق ﻷﻛﺴـﻴﺪ اﻟﻔﺎﻧـﺎدﻳﻮم ﻋـﲆ ﻛﻮﻛـﺐ ﻧﺠﻤﻲ ﻳﻘﻮل ﺑﻴﻠﻴﺘﻴﻴﻪ " : ﻳﺤﻈﻰ ﻫﺬا اﻟﺠـﺰيء ﺑﺎﻫﺘﻤﺎ م ﻛﺒ ﻟﺪى ﻋﻠﻤﺎء اﻟﻔﻠﻚ ﻷﻧﻪ ﻳﻤﻜﻦ أن ﻳﻜﻮن ﻟﻪ ﺗﺄﺛ ﻛﺒ ﻋﲆ ﺑﻨﻴﺔ اﻟﻐﻼف اﻟ ﺠﻮي ﻟﻠﻜﻮاﻛﺐ اﻟﻌﻤﻼﻗﺔ اﻟﺴﺎﺧﻨﺔ ﺣﻴﺚ ﻳﻠﻌﺐ ﻫﺬا اﻟﺠﺰيء دور اً ﺎً ﻣﺸﺎﺑﻬ ﻟﻸوزون ﻛﻮﻧـﻪ ﻓﻌـﺎﻻً ﻟﻠﻐﺎﻳﺔ ﰲ ﺗﺴـﺨ اﻟﻐـﻼف اﻟﺠـﻮي اﻟﻌﻠـﻮي ﻟﻸرض ". ﻟﺪى ﺑﻴﻠﻴﺘﻴﻴﻪ وﻓﺮﻳﻘﻪ اﻟﺪاﻓﻊ ﻌﺮﻓﺔ ا ﺰﻳﺪ ﻋﻦ اﻟﻜﻮﻛـﺐ WASP-76b واﻟﻜﻮاﻛـﺐ اﻷﺧﺮى ﺷﺪﻳﺪة اﻟﺤﺮارة وﻳـﺄﻣﻠﻮن أﻳ أن ﺎً ﻀـ ﻳﺴﺘﻔﻴﺪ اﻟﺒﺎﺣﺜﻮن اﻵﺧﺮون ﻣﻤﺎ ﺗﻌﻠﻤﻮه ﻣـﻦ ﻫﺬا اﻟﻜﻮﻛـﺐ اﻟﻌﻤـﻼق اﻟﻨﺠﻤـﻲ وﻳﻄﺒﻘـﻮه ﻟﺘﺤﺴ ﻓﻬﻤﻨﺎ ﻟﻜﻮاﻛﺐ ﻧﻈﺎﻣﻨـﺎ اﻟـ ـ ﺸﻤﴘ ــ وﻛﻴﻒ ﻧﺸﺄت . ﻳﻮاﺻﻞ ﻣﺮﺻﺪ ﺟﻴﻤﻴﻨﻲ اﻟﺪوﱄ ا ﺘﺎح ﻟﻌ ﻠﻤﺎء اﻟﻔﻠﻚ ﰲ ﺟﻤﻴﻊ أﻧﺤـﺎء اﻟﻌـﺎﻟﻢ ﺗﻘـﺪﻳﻢ رؤى ﺟﺪﻳـﺪة ﺗـﺪﻓﻊ ﻓﻬﻤﻨـﺎ ﻟﻠﺒﻨﻴـﺔ اﻟﻔﻴﺰﻳﺎﺋﻴﺔ واﻟﻜﻴﻤﻴﺎﺋﻴﺔ ﻟﻠﻌﻮاﻟﻢ اﻷﺧﺮى وﻗﺎل ﻣﺎرﺗﻦ ﺳﺘﻴﻞ ﻣﺪﻳﺮ ﺑﺮﻧﺎﻣﺞ ﻣﺮﺻﺪ ﺟﻴﻤﻴﻨـﻲ اﻟﺘﺎﺑﻊ ﺆﺳﺴﺔ اﻟﻌﻠﻮم اﻟﻮﻃﻨﻴـﺔ اﻷﻣﺮﻳﻜﻴـﺔ : " ﻣﻦ ﺧﻼل ﺑﺮاﻣﺞ اﻟﺮﺻﺪ ﻫﺬه ﻧﻘﻮم ﺑﺘﻄﻮﻳﺮ ﺻﻮرة أوﺿﺢ ﻟﻠﻜﻮن اﻷوﺳﻊ وﻣﻜﺎﻧﻨﺎ ﻓﻴﻪ ." ﻳﻘـﻮل ﺑﻴ ـﻮرن ﺑﻴﻨﻴﻜـﻲ اﻷﺳـﺘﺎذ ﺑﺠﺎﻣﻌ ـﺔ ﻣﻮﻧﱰﻳﺎل وا ﺆﻟﻒ ا ﺸﺎرك ﰲ اﻟﺪراﺳﺔ " : ﻟﻘـﺪ اﺳـﺘﺨﺪﻣﺖ أﺟﻴـﺎل ﻣـﻦ اﻟﺒـﺎﺣﺜ ﻛﻮﻛـﺐ ا ﺸﱰي و وزﺣـﻞ و وأوراﻧـﻮس و وﻧﺒﺘـﻮن ﻟﻘﻴﺎس وﻓﺮة اﻟﻬﻴﺪروﺟ واﻟﻬﻴﻠﻴﻮم ﻟﻘﻴ ﺎس ﻧﻈﺮﻳﺎت ﺗﻜﻮﻳﻦ اﻟﻜﻮاﻛﺐ اﻟﻐ ﺎزﻳﺔ وﺑﺎ ﺜﻞ ﻓﺈن ﻗﻴﺎﺳﺎت اﻟﻌﻨﺎﴏ اﻷﺛﻘﻞ ﻣﺜﻞ اﻟﻜﺎﻟﺴـﻴﻮم أو ا ﻐﻨﻴﺴــﻴﻮم ﻋــﲆ اﻟﻜﻮﻛــﺐ WASP-76b ﺳﺘﺴﺎﻋﺪ ﰲ ﻓﻬﻢ ﻛﻴﻔﻴـﺔ ﺗﻜـﻮﻳﻦ اﻟﻜﻮاﻛـﺐ اﻟﻐﺎزﻳﺔ ﺑﺸﻜﻞ أﻛﱪ .