Free Astronomy Magazine November-December 2024 ARABIC VERSION

Barnard’s Star has a sub-Earth mass planet byESO − BárbaraFerreira singtheEuropeanSouth-ern Observatory’s Very Large Telescope(ESO’sVLT),as- tronomers have discovered an exo- planet orbiting Barnard’s star, the closestsinglestartoourSun.Onthis newly discovered exoplanet, which has at least half the mass of Venus,ayearlastsjustoverthreeEarth days. The team’s observations also hintattheexistenceofthreemore exoplanet candidates, in various or- bits around the star. Locatedjustsixlight-yearsaway, Barnard’sstaristhesecond-closest stellar system — after Alpha Cen- tauri’sthree-stargroup—andthe NOVEMBER-DECEMBER2024 U ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 4 ﻧﻮﻓﻤﺒﺮ - ﺩﻳﺴﻤﺒﺮ 2 0 2 4 ﻧ ﻢ ﺑﺮ ﺎرد ﻟﺪ ﮫ ﻮﻛﺐ ﺘﮫﻛﺘﻠ أﻗﻞ ﻣﻦ ﻛﺘﻠﺔ اﻷرض : ﻘﻠﻢ ﺎر ﺮا ﻓ ﺮا - اﻟﻤﺮﺻﺪ اﻷوروﺑﻲ اﻟـﺠﻨﻮﺑﻲ ﻈﻬـﺮ ﻫــﺬا اﻟﺮﺳـﻢ اﻟﺘﺨ ﻠـﻲ ﻮﻛــﺐ ﺑﺮــﺎرد ــﺪورﺣــﻮل وﻫـﻮ ﻮﻛــﺐ أﻗـﻞ ﻣـﻦ ﻛﺘﻠــﺔ اﻷرض ﺗـﻢ اﻛﺘﺸـﺎﻓﮫ ــﻢ ﺑﺮ ــﺎرد ﻧ . ﺗــﻢ اﻛﺘﺸــﺎﻓ ﮫ ﺎﺳــﺘﺨﺪام ــﺎف ﻣﻄ اﺳ ﺳــﻮ اﻟﻤﺘﺼــﻞ ﺎﻟﺘﻠﺴــ ﻮب اﻟﻜﺒــ ﺟــﺪ اً اﻟﺘــﺎﺑﻊ ﻟﻠﻤﺮﺻــﺪ اﻷ وروﺑﻲ اﻟ ـ ﺠﻨﻮﺑﻲ وﺗﻤﻜﻦ ﻋﻠﻤﺎء اﻟﻔﻠﻚ ﻣﻦ ﺗﺄﻛ ﺪ ذﻟـﻚ ﺎﺳـﺘﺨﺪام ﺑ ﺎﻧـﺎت ﻣـﻦ أدوات أﺧـﺮى . ـﺘﻤﻜﻦ ﻟـﻢ ــﺪ اﻛﺘﺸــﺎفﺳـــﺎﺑﻖ ﻓــﻲﻋــﺎم ﻋﻠﻤــﺎء اﻟﻔﻠــﻚ ﻣـــﻦ ﺗﺄﻛ 2018 ﺣـــﻮل ﻧﻔــﺲ اﻟــﻨ ﻢ ﺎﺳـــﺘﺨﺪامﻫــﺬﻩ اﻟﺒ ﺎﻧـــﺎت . ﺗﺴﺘﻤﺮ اﻟﺴﻨﺔ أﻛ ﻣﻦ ﺛﻼﺛﺔ أ ﺎم أرﺿ ﺔ ﻘﻠﻴﻞ ﻋﻠﻰﻫﺬا اﻟ ﻮﻛﺐ اﻟ ﻨ ﻤﻲ اﻟﻤﻜﺘﺸﻒﺣﺪ ﺜ ﺎً ﻳ واﻟﺬ ﻠـﻎ ﻧﺼﻒﻛﺘﻠﺔ ﻮﻛﺐ اﻟﺰﻫﺮة ﻋﻠﻰ اﻷﻗﻞ وﻟﻜﻨﮫ ﺳﺎﺧﻦ ﺟﺪ اً ﻟﺪﻋﻢ وﺟﻮد اﻟﻤﺎء اﻟﺴﺎﺋﻞ . ﺎﺳـﺘﺨﺪام اﻟﺘﻠﺴﻜﻮب اﻟﻜﺒ اً ﺟﺪ اﻟﺘـﺎﺑﻊ ﻟﻠﻤﺮﺻﺪ اﻟﺠﻨﻮﺑﻲ اﻷور وﺑﻲ اﻛﺘﺸﻒ ﻋﻠﻤـﺎء اﻟﻔﻠﻚ ﻛﻮﻛﺒﺎً ﻧﺠﻤﻴﺎً ﻳﺪور ﺣﻮل ﻧﺠﻢ ﺑﺮﻧـﺎرد وﻫﻮ أﻗﺮب ﻧﺠﻢ ﻣﻨﻔﺮد إﱃ اﻟ . ﺸﻤﺲ ﻋﲆ ﻫﺬا اﻟﻜﻮﻛﺐ اﻟ ﻨﺠﻤﻲ ا ﻜﺘﺸـﻒ ﺣـﺪﻳﺜًﺎ واﻟﺬي ﺗﺒﻠﻎ ﻛﺘﻠﺘﻪ ﻧﺼﻒ ﻛﺘﻠﺔ ﻛﻮﻛﺐ اﻟﺰﻫﺮة ﻋﲆ اﻷﻗﻞ ﻳﺴﺘﻤﺮ اﻟﻌﺎم أﻛﺜﺮ ﻣﻦ ﺛﻼﺛﺔ أﻳـ ﺎم أرﺿﻴﺔ ﺑﻘﻠﻴﻞ إﺿـﺎﻓﺔ ﻟـﺬﻟﻚ ﺗﺸـ أرﺻـﺎد اﻟﻔﺮﻳﻖ إﱃ إﻣﻜﺎﻧﻴـﺔ وﺟـﻮد ﺛﻼﺛـﺔ ﻛﻮاﻛـﺐ ــــــــ ﻧﺠﻤﻴﻪ أﺧﺮى ﻣﺤﺘﻤﻠﺔ ﰲ ﻣﺪارات ﻣﺨﺘﻠﻔـﺔ . ﺣﻮل اﻟﻨﺠﻢ ﻳﻘﻊ ﻧﺠﻢ ﺑﺮ ﻧﺎرد ﻋﲆ ﺑﻌﺪ ﺳﺖ ﺳﻨﻮات ﺿﻮﺋﻴﺔ ﻓﻘﻂ وﻫﻮ ﺛﺎﻧﻲ أﻗﺮب ﻧﻈﺎم ـ ﻧﺠﻤـﻲ ﺑﻌـﺪ ﻧﻈـﺎم اﻟﻨ ﺠـﻮم اﻟﺜﻼﺛـﺔ أﻟﻔـﺎ ﻗﻨﻄﻮرس اﻟـﺬي ﻳﺒﻌـﺪ ﻋﻨـﺎ أرﺑـﻊ ﺳـﻨﻮات - ﺿﻮﺋﻴﺔ وأﻗﺮب ﻧﺠﻢ ﻓﺮدي إﻟﻴﻨﺎ .