Free Astronomy Magazine March-April 2026 ARABIC VERSION

MARCH-APRIL2026 T hisartist’sconceptshowswhattheultra-hotsuper-Earthexoplanet TOI-561 b could look like based on observations from NASA’s James WebbSpaceTelescopeandotherobservatories.Webbdatasuggeststhat theplanetissurroundedbyathickatmosphereaboveaglobalmagma ocean. TOI-561 b is the innermost of four planets orbiting TOI-561, a 10-billion-year-oldG-typestarlocatedroughly280light-yearsfromEarth,in the constellation Sextans. [NASA, ESA, CSA, Ralf Crawford (STScI)] The magma ocean could circulate some heat, but without an atmos- phere,thenightsidewouldprobably besolid,limitingflowawayfromthe dayside. A thin layer of rock vapor onthesurfaceofthemagmaocean isalsopossible,butonitsownwould likely have a much smaller cooling effect than observed. “We reallyneedathickvolatile- richatmosphere toexplainalltheobservations,” said AnjaliPiette,coauthorfromtheUni- versity of Birmingham, United King- dom. “Strong winds would cool the daysidebytransportingheatoverto thenightside.Gaseslikewatervapor would absorb some wavelengths of near-infrared light emitted by the surface before they make it all the wayupthroughtheatmosphere. (The planet would look colder be- cause the telescope detects lesslight.)It’salsopossiblethattherear e brightsilicatecloudsthatcooltheat- mosphere by reflecting starlight.” While the Webb observations pro- videcompellingevidenceforsuchan atmosphere, the question remains: How can a small planet exposed to suchintenseradiationcanholdonto ﻌــﺮض اﻟﺮﺳـــﻢ ﻫــﺬا ــﮫ اﻟ ﻮﻛــﺐ اﻟﻌﻤـــﻼق ﻓــﺎﺋﻖ اﻟـــ ـــﺪو ﻋﻠ ﻗــﺪ ﻳ اﻟﺘﺨ ﻠــﻲ اﻟﺸـــ ﻞ اﻟــﺬ ـ ﺤﺮارة TOI-561 b اﺳـــﺘﻨﺎد اً إﻟــــﻰ أرﺻـــﺎد ـــﺐ اﻟﻔﻀــــﺎﺋﻲ اﻟﺘـــﺎﺑﻊ ﻟﻨﺎﺳـــﺎ وﻏـــ ﻩ ﻣــــﻦ ﺗﻠﺴـــ ﻮبﺟـــ ﻤﺲو اﻟﻤﺮاﺻﺪ . ﺗﺸ ﺑ ﺎﻧﺎت ﺗﻠﺴ ﻮب ـﺐ إﻟـﻰ أن اﻟ ﻮﻛـﺐ ﻣ و ﺤـﺎط ﻐـﻼفﺟـﻮيﻛﺜ ـﻒﻓـﻮق ﻣﺤـ ﻂ ﻋﺎﻟﻤﻲ ﻣﻦ اﻟﺼﻬﺎرة ﻌﺪ . TOI-561 b ﺗﺪورﺣﻮل أﻗﺮ اﻟ ﻮاﻛﺐ اﻷرﻌﺔ اﻟ اﻟﻨ ﻢ TOI-561 ــﻢ ﻣــﻦ اﻟﻨـﻮع وﻫــﻮ ﻧ G ﻳ ﻠـﻎ ﻋﻤــﺮﻩ 10 ــﺎراتﺳــﻨﺔ ﻣﻠ و ﻘــﻊ ﻋﻠــﻰ ُﻌــﺪ 280 ﺳـﻨﺔ ﺿـﻮﺋ ــ ﺎً ﺔ ﺗﻘﺮ ﻣﻦ اﻷرض ﻓﻲ ﻮﻛ ﺔ اﻟﺴﺪس . [NASA, ESA, CSA, Ralf Crawford (STScI)] ﻗﺪ ﻳ ﺴﺎﻫﻢ ﻣﺤ ﻴﻂ اﻟﺼﻬﺎرة ﰲ ﺗﺪوﻳﺮ ﺑﻌﺾ اﻟﺤﺮارة وﻟﻜﻦ ﺑﺪون ﻏﻼف ﺟـﻮي ﺳـﻴﻜﻮن اﻟﺠﺎ ﻧﺐ اﻟﻠﻴﲇ ﻋﲆ اﻷرﺟﺢ ﺻﻠﺒ ﺎً ﻣﻤـﺎ ﻳﺤـﺪ ﻣـﻦ ﺗــﺪﻓﻖ اﻟﺤـﺮارة ﺑﻌﻴـﺪ ﻋـ اً ﻦ اﻟﺠﺎﻧـﺐ اﻟﻨﻬﺎري . ﻣﻦ ا ﻤﻜـﻦ أﻳﻀـ ﺎً وﺟـﻮد ﻃﺒﻘـﺔ رﻗﻴﻘﺔ ﻣﻦ ﺑﺨﺎر اﻟﺼﺨﻮر ﻋﲆ ﺳﻄﺢ ﻣﺤﻴﻂ اﻟﺼﻬﺎرة ﻟﻜﻨﻬﺎ وﺣﺪﻫﺎ ﺳﺘﻜﻮن ﻋﲆ اﻷرﺟﺢ ذات ﺗﺄﺛ ﺗﱪﻳﺪ أﻗﻞ ﺑ ﻜﺜ ﻣﻤﺎ . رﺻﺪ ﻗﺎﻟﺖ أﻧﺠﺎﱄ ﺑﻴﻴﺖ ا ﺆﻟﻔﺔ ا ﺸﺎرﻛﺔ ﻣـﻦ ﺟﺎﻣﻌـﺔ ﺑﺮﻣﻨ ﻐﻬﺎم، ا ﻤﻠﻜـﺔ ا ﺘﺤـﺪة " : ﻧﺤـﻦ ﺣﻘًـﺎ ﺑﺮﻣﻨﻐﻬـﺎم ﰲ ا ﻤﻠﻜ ـﺔ ا ﺘﺤــﺪة " : ﺳـﺘُﱪد اﻟﺮﻳﺎح اﻟﻘﻮﻳﺔ اﻟﺠﺎﻧﺐ اﻟﻨﻬﺎري ﻋﻦ ﻃﺮﻳـﻖ ﻧﻘﻞ اﻟﺤﺮارة إﱃ اﻟﺠﺎﻧـﺐ اﻟﻠـﻴﲇ . ﺳـﺘﻤﺘﺺ اﻟﻐـﺎزات ﻣﺜـﻞ ﺑﺨـﺎر ا ـﺎء ﺑﻌـﺾ أﻃـﻮال ﻣﻮﺟﺎت اﻷﺷـﻌﺔ ﺗﺤـﺖ اﻟﺤﻤـﺮاء اﻟﻘﺮﻳﺒـﺔ ا ﻨﺒﻌﺜﺔ ﻣﻦ اﻟﺴﻄﺢ ﻗﺒﻞ أن ﺗﺼـﻞ إﱃ أﻋـﲆ اﻟﻐﻼف اﻟﺠﻮي ) . ﺳﻴﺒﺪو اﻟﻜﻮﻛـﺐ أﺑـﺮد ﻷن اﻟﺘﻠﺴﻜﻮب ﻳﺮﺻﺪ ﺿﻮءًا أﻗﻞ .( ﻣـﻦ ا ﻤﻜـﻦ أﻳﻀًﺎ وﺟﻮد ﺳﺤﺐ ﺳﻴﻠﻴﻜﺎﺗﻴﺔ ﺳﺎﻃﻌﺔ ﺗُﱪد اﻟﻐﻼف اﻟﺠﻮي ﻋـﻦ ﻃﺮﻳـﻖ ﻋﻜـﺲ ﺿـﻮء اﻟﻐﻼف اﻟﺠﻮي ﻋـﻦ ﻃﺮﻳـﻖ ﻋﻜـ ﺲ ﺿـﻮء اﻟﻨﺠــﻮم . ﺑﻴﻨﻤـﺎ ﺗﻘـﺪ أم رﺻـﺎد ﺗﻠﺴــﻜﻮب ﺟﻴﻤﺲ وﻳﺐ أدﻟﺔ داﻣﻐﺔ ﻋﲆ وﺟﻮد ﻣﺜﻞ ﻫﺬا اﻟﻐﻼف اﻟﺠﻮي ﻳﺒﻘﻰ اﻟﺴﺆال ﻣﻄﺮوﺣ : ﺎً ﻛﻴﻒ ﻳ ﻤﻜﻦ ﻟﻜﻮﻛـﺐ ﺻـﻐ ﻣُﻌـﺮّض ﺜـﻞ ﻫـﺬا اﻹﺷﻌﺎع اﻟﺸﺪﻳﺪ أن ﻳﺤﺘﻔﻆ ﺑﺄي ﻏﻼفﺟﻮي ﻋﲆ اﻹﻃﻼق، ﻓﻀﻼً ﻋﻦ ﻏﻼف ﺟﻮي ﻛﺜﻴـﻒ ﻛﻬﺬا؟ ﻻ ﺑﺪ أن ﺑﻌﺾ اﻟﻐﺎزات ﺗﺘـ ـ ﴪب إﱃ اﻟﻔﻀﺎء وﻟﻜﻦ رﺑﻤﺎ ﻟﻴﺲ ﺑﺎﻟﻜﻔﺎءة ا ﺘﻮﻗﻌﺔ . - ﻣﺎﺭﺱ ﺃﺑﺮﻳﻞ 2 0 2 6