Free Astronomy Magazine May-June 2025 ARABIC VERSION

One such effort was led by Jacob BeanfromtheUniversityofChicago, whose team created an instrument called MAROON-X, which is de- signedspecificallytosearchfordis- tant planets around red dwarf stars. MAROON-X is mounted on the Gemini North telescope, one half of the International Gemini Obser- vatory, funded in part by the U.S. National Science Foundation and operated by NSF NOIRLab. MAROON-X hunts for exoplanets usingtheradialvelocitytechnique, meaningitdetectsthesubtleback andforthwobbleofastarasitsex- oplanets gravitationally tug on it, which causes the light emitted by the star to shift ever so slightly in wavelength. The powerful instru- mentmeasuresthesesmallshiftsin light so precisely that it can even teaseapartthenumberandmasses oftheplanetsthatmustbecircling thestartohavetheobservedeffect. Afterrigorouslycalibratingandan- alyzingdatatakenduring112nights over a period of three years, the teamfoundsolidevidenceforthree exoplanetsaroundBarnard’sStar, twoofwhichwerepreviouslyclassi- fied as candidates. The team also combined data from MAROON-X with data from a 2024 study done with the ESPRESSO instrument at the European Southern Observa- tory’sVeryLargeTelescopeinChile toconfirmtheexistenceofafourth planet,elevatingitaswellfromcan- didatetobonafideexoplanet. “It’s a really exciting find — Barnard’s Starisourcosmicneighbor,andyet we know so little about it,” says Ritvik Basant, PhD student at the UniversityofChicagoandfirstau- MAY-JUNE2025 ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 5 أﺣﺪ ﻫﺬه اﻟﺠﻬﻮد ﺎ ﻗﺎدﻫ ﺟـﺎﻛﻮب ﺑـ ﻣـﻦ ﺟﺎﻣﻌﺔ ﺷﻴﻜﺎﻏﻮ ﺣﻴـﺚ اﺑﺘﻜـﺮ ﻓﺮﻳﻘـﻪ أداة ﺗُﺪﻋﻰ ﻣﺎرون إﻛﺲ - ) MAROON-X ( وﻫﻲ ﻣُﺼﻤﻤﺔ ﺧﺼﻴﺼًﺎ ﻟﻠﺒﺤﺚ ﻋﻦ ﻛﻮاﻛﺐ ﺑﻌﻴﺪة ﺗﺪور ﺣﻮل ﻧﺠﻮم اﻟﻘﺰم اﻷﺣﻤﺮ . ﺗﻢ ﺗﺮﻛﻴـﺐ ﺎرونﻣ - إﻛﺲ ﻋﲆ ﺗﻠﺴﻜﻮب ﺟﻴﻤﻴﻨﻲ ﻧﻮرث اﻟ ﺬي ﻳُﻤﺜﻞ ﻧﺼﻒ ﻣﺮﺻـﺪ ﺟﻴﻤﻴﻨـﻲ اﻟـﺪوﱄ وا ﻤﻮل ﻣﻦ ﻗِﺒﻞ ا ﺆﺳﺴﺔ اﻟﻮﻃﻨﻴﺔ ﻟﻠﻌﻠـﻮم اﻷﻣﺮﻳﻜﻴﺔ وﻳُﺪﻳﺮه ﻣﺨﺘﱪ ﻧﻮﻳﺮﻻب . ﺗﺒﺤـﺚ أداة - ﻣـﺎرون إﻛــﺲ ﻋـﻦ اﻟﻜﻮاﻛـﺐ اﻟﻨﺠﻤﻴــﺔ ﺑﺎﺳــﺘﺨﺪام ﺗﻘﻨﻴــﺔ اﻟــ ـ ﴪﻋﺔ اﻟﺸﻌﺎﻋﻴﺔ ﻣﻤﺎ ﻳﻌﻨﻲ أﻧﻬـ ﺗ ﺎ ﺮﺻـﺪ اﻟﺘﺬﺑـﺬب اﻟﻄﻔﻴﻒ ذﻫﺎﺑ ﺎً ﺎً وإﻳﺎﺑ ﻟﻨﺠﻢ ﻧﺎ ﺗﺞ ﻋﻦ ﺳﺤﺐ ﻛﻮاﻛﺒﻪ ﻟﻪ ﺟﺎذﺑﻴﺎً، اﻷﻣـﺮ اﻟـﺬي ﻳﺘﺴـﺒﺐ ﰲ اﻧﺰﻳﺎح ﻃﻔﻴـﻒ ﻟﻠﻐﺎﻳـﺔ ﰲ اﻟﻄـﻮل ا ـﻮﺟﻲ ﻟﻠﻀﻮء ا ﻨﺒﻌﺚ ﻣﻦ اﻟﻨﺠﻢ . ﻳﻘﻴﺲ ﻫﺬا اﻟﺠﻬﺎز اﻟﻘﻮي ﻫﺬه اﻻﻧﺰﻳﺎﺣـﺎت اﻟﺼﻐ ة ﰲ اﻟﻀﻮء ﺑﺪﻗﺔ ﻋﺎﻟﻴﺔ ﻟﺪرﺟـﺔ أﻧـﻪ ﻳﻤﻜﻨﻪ ﺣﺘﻰ ﺗﺤﺪﻳﺪ ﻋﺪد وﻛﺘﻞ اﻟﻜﻮاﻛﺐ اﻟﺘ ﻲ ﻳﺠﺐ أن ﺗﺪور ﺣﻮل اﻟﻨﺠﻢ ﻹﺣـﺪاث اﻟﺘـﺄﺛ ا ﺮﺻـﻮد . ﺑﻌـﺪ ﻣﻌـﺎﻳﺮة وﺗﺤﻠﻴـﻞ دﻗﻴﻘـ ﻟﻠﺒﻴﺎﻧﺎت اﻟﺘﻲ ﺗﻢ ﺟﻤﻌﻬـﺎ ﺧـﻼل 112 ﻟﻴﻠـﺔ ﻋﲆ ﻣﺪى ﺛﻼث ﺳﻨﻮات وﺟﺪ اﻟﻔﺮﻳـﻖ دﻟـﻴﻼً ﻗﺎﻃﻌ ﺎ ﻋﲆ وﺟﻮد ﺛﻼﺛﺔ ﻛﻮاﻛﺐ ﺣـﻮل ﻧﺠـﻢ ﺑﺮﻧﺎرد اﺛﻨﺎن ﻣﻨﻬﺎ ﺻﻨﻔﺎ ﻛﻤﺮﺷﺤ ﰲ وﻗﺖ . ﺳﺎﺑﻖ ﻛﻤﺎ ﺟﻤﻊ اﻟﻔﺮﻳﻖ ﺑﻴﺎﻧـﺎت ﻣـﻦ أداة ـﺲ - ﻣﺎرون إﻛﺲ ﻣﻊ ﺑﻴﺎﻧﺎت ﻣﻦ دراﺳﺔ أﺟﺮﻳﺖ ﻋـﺎم 2024 ﺑﺎﺳـﺘﺨﺪام ﺟﻬـﺎز إﺳﱪﻳﺴــﻮ ) ESPRESSO ( ﰲ اﻟﺘﻠﺴـﻜﻮب اﻟﻜﺒـ ﺟـﺪ اً اﻟﺘﺎﺑﻊ ﻟﻠﻤﺮﺻﺪ اﻷوروﺑﻲ اﻟﺠﻨﻮﺑﻲ ﺗﺸﻴﲇ ﰲ ﻟﺘﺄﻛﻴﺪ وﺟﻮد ﻛﻮﻛﺐ راﺑﻊ ﺣﻮل اﻟﻨﺠﻢ ﻣﻤـﺎ أدى أﻳﻀًﺎ إﱃ ﺗﺮﻗﻴﺘﻪ ﻣﻦ ﻣﺮﺗﺒـﺔ ﻣﺮﺷـﺢ إﱃ ﻛﻮﻛﺐ ﻧﺠﻤﻲ . ﺣﻘﻴﻘﻲ ﻳﻘﻮل رﻳﺘﻔﻴﻚ ﺑﺎﺳـﺎﻧﺖ ﻃﺎﻟـﺐ دﻛﺘـﻮراه ﰲ ﺟﺎﻣﻌـﺔ ﺷـﻴﻜﺎﻏﻮ وا ﺆﻟـﻒ اﻷول ﻟﻠﻮرﻗـﺔ اﻟﺒﺤﺜﻴﺔ ا ﻨﺸﻮرة ﰲ ﻣﺠﻠﺔ رﺳﺎﺋﻞ اﻟﻔﻴﺰﻳـﺎء اﻟﻔﻠﻜﻴﺔ " : إﻧﻪ اﻛﺘﺸﺎف ﻣﺜـ ﺣﻘـ -ﺎ ﻧﺠـﻢ ﺑﺮﻧﺎرد ﻫـﻮ ﺟﺎر ﻧـﺎ اﻟﻜـﻮﻧﻲ وﺣﺘـﻰ اﻵن ﻻ ﻧﻌﺮف ﻋﻨﻪ إﻻ اﻟﻘﻠﻴﻞ . ﻣﺎﻳﻮ - ﻳﻮﻧﻴﻮ 2 0 2 5