Free Astronomy Magazine July-August 2024 ARABIC VERSION

mid-infrared light given off by an object depends largely on how hot it is, the brightness data captured by Webb can then be used to calculate the planet’s temperature. The team used Webb’s MIRI (Mid-Infrared In- strument) to measure light from the WASP-43 system every 10 seconds for more than 24 hours. “By observing over an entire orbit, we were able to calculate the tem- perature of different sides of the planet as they rotate into view,” ex- plained Bell. “From that, we could construct a rough map of tempera- ture across the planet.” The measurements show that the dayside has an average temperature of nearly 2,300 degrees Fahrenheit (1,250 degrees Celsius) – hot enough to forge iron. Meanwhile, the night- side is significantly cooler at 1,100 degrees Fahrenheit (600 degrees Celsius). The data also helps locate the hottest spot on the planet (the “hotspot”), which is shifted slightly eastward from the point that re- ceives the most stellar radiation, where the star is highest in the planet’s sky. This shift occurs because of supersonic winds, which move heated air eastward. ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 19 ﺗُﻈﻬــﺮ ﻫـﺬﻩ اﻟ ﻤ ﻤﻮﻋــﺔ ﻣــﻦ اﻟــ ـ ﺨﺮاﺋﻂدرﺟــﺔ ﺣــﺮارة اﻟــ ـ ﺠﺎﻧﺐ اﻟﻤﺮ ــﻲ ﻣــﻦ اﻟ ﻮﻛــﺐ اﻟــ ـ ﺨﺎرﺟﻲ اﻟﻌﻤــﻼق اﻟﻐــﺎزي اﻟﺴـﺎﺧﻦ WASP-43 b ، أﺛﻨـﺎء دوران اﻟ ﻮﻛـﺐﺣـﻮل ﻧ ﻤـﮫ . ﺗـﻢ ﺣﺴـﺎب درﺟـﺎت اﻟـ ـ ﺤﺮارة ﻨـﺎءً ﻋﻠـﻰ أﻛـ ﻣـﻦ 8000 ــﺎسﺳــﻄﻮع ﻟﻀــﻮء اﻷﺷــﻌﺔ ﺗﺤـــﺖ اﻟــ ﻗ ـ ﻤﺮاء اﻟﻤﺘﻮﺳــﻄﺔ ﻣــﻦ 5 إﻟــﻰ 12 ﻣ ﻜـــﺮون اﻟﻤﻜﺘﺸــﻒﻣــﻦ ﻧﻈــﺎم اﻟﻨﺠـــﻮ م واﻟ ﻮﻛﺐ ﺑﻮاﺳﻄﺔ MIRI ) أداة اﻷﺷﻌﺔ ﺗﺤﺖ اﻟ ـ ﻤﺮاء اﻟﻤﺘﻮﺳﻄﺔ ( ﻋﻠﻰ ﺗﻠﺴ ﻮبﺟ ﻤﺲو ﺐ اﻟﻔﻀﺎﺋﻲ اﻟﺘﺎﺑﻊ ﻟﻨﺎﺳﺎ . ﺸ ﻞ ﻋﺎم ﻠﻤﺎ ﺎن اﻟ ـ ﺠﺴﻢ أﻛ ﺳﺨﻮﻧﺔ ﻠﻤﺎ زاد ﺿﻮء اﻷﺷـﻌﺔ ﺗﺤـﺖ اﻟـ ـ ﺼـﺪرﻩ ﻤﺮاء اﻟﻤﺘﻮﺳـﻄﺔ اﻟـﺬ . [Illustration: NASA, ESA, CSA, Ralf Crawford (STScI). Science: Taylor Bell (BAERI), Joanna Barstow (The Open University), Michael Roman (University of Leicester [( - ﻳﻮﻟﻴﻮ ﺃﻏﺴﻄﺲ 2 0 2 4 ﺑﻤﺎ أن ﻛﻤﻴﺔ ﺿﻮء اﻷﺷﻌﺔ ﺗﺤـﺖ اﻟﺤﻤـﺮاء ا ﺘﻮﺳﻄﺔ ا ﻨﺒﻌﺜﺔ ﻣﻦ ﺟﺴﻢ ﻣـﺎ ﺗ ﻌﺘﻤـﺪ إﱃ ﺣﺪ ﻛﺒ ﻋﲆ ﻣﺪى ﺣﺮارﺗﻪ ﻓﻴﻤﻜﻦ ﺑﻌﺪ ذﻟـﻚ اﺳﺘﺨﺪام ﺑﻴﺎﻧﺎت اﻟﺴـﻄﻮع اﻟﺘـﻲ اﻟﺘﻘﻄﻬـﺎ ﺗﻠﺴــﻜﻮب وﻳـﺐ ﻟﺤﺴـﺎب درﺟـﺔ ﺣـﺮارة اﻟﻜﻮﻛﺐ . اﺳﺘﺨﺪم اﻟﻔﺮ ﻳﻖ ﺟﻬﺎز أداة ) ﻣ ي اﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤﺮاء ا ﺘﻮﺳـﻄﺔ ( ﻟﻘﻴـﺎس اﻟﻀﻮء اﻟﺼﺎدر ﻣﻦ ﻧﻈـﺎم WASP-43 ﻛـﻞ 10 ﺛﻮانٍ ﻷﻛﺜﺮ ﻣﻦ 24 . ﺳﺎﻋﺔ أوﺿﺢ »: ﺑﻴﻞ ﻣﻦ ﺧﻼل ﻣﺮاﻗﺒﺔ ﻣﺪار ﻛﺎﻣـﻞ ﺗﻤﻜﻨﺎ ﻣﻦ ﺣﺴﺎب درﺟﺔ ﺣـﺮارة اﻟﺠﻮاﻧـﺐ ا ﺨﺘﻠﻔﺔ ﻟﻠﻜﻮﻛﺐ أﺛ ﻨـﺎء دوراﻧﻬـﺎ ﺑﺎﻟﻨﺴـﺒﺔ ﻟ ﻸﻓﻖ ﻣﻦ ذﻟﻚ ﻳﻤﻜﻨﻨﺎ ﺑﻨﺎء ﺧﺮﻳﻄﺔ ﺗﻘﺮﻳﺒ ﻴﺔ ﻟﺪرﺟﺔ اﻟﺤﺮارة ﰲ ﺟﻤﻴـﻊ أﻧﺤـﺎء اﻟﻜﻮﻛـﺐ . ﺗﻈﻬﺮ اﻟﻘﻴﺎﺳﺎت أن ﻣﺘﻮﺳﻂ درﺟﺔ اﻟﺤﺮارة ﰲ اﻟﺠﺎﻧـﺐ اﻟﻨﻬـﺎري ﻳﺒﻠـﻎ ) 1250 درﺟـﺔ وﻫـﻮ ( ﻣﺌﻮﻳـﺔ ﰲ ﻏﺎﻳـﺔ اﻟﺴـﺨﻮﻧﺔ ﻟﻠﻘﻴـﺎم ﺑ ﺘﺸﻜﻴﻞ اﻟﺤ أن ﺣـﰲ ﺪﻳﺪ اﻟﺠﺎﻧـﺐ اﻟﻠـﻴﲇ أﻛﺜﺮ ﺑﺮودة ﻋﻨﺪ 600 درﺟﺔ ﻣ . ﺌﻮﻳﺔ ﺗﺴـﺎﻋﺪ اﻟﺒﻴﺎﻧـﺎت أﻳﻀـ ﺎً ﰲ ﺗﺤﺪﻳـﺪ ﻣﻮﻗـﻊ اﻟﻨﻘﻄـﺔ اﻷﻛﺜﺮ ﺳﺨﻮﻧ ﺔ ﻋﲆ اﻟﻜﻮﻛﺐ اﻟﺘﻲ ﺗﻨ و ﺤـﺮف ﻗﻠﻴﻼً ﻧﺤﻮ اﻟﴩق ﻣﻦ اﻟﻨﻘﻄﺔ اﻟﺘﻲ ﺗﺴﺘﻘﺒﻞ ﻣﻌﻈﻢ اﻹﺷﻌﺎع اﻟﻨﺠﻤﻲ ﺣﻴﺚ ﻳﻜﻮن اﻟـﻨﺠﻢ أﻋﲆ ﰲ ارﺗﻔﺎع ﰲ ﺳـﻤﺎء اﻟﻜﻮﻛـﺐ وﻳﺤـﺪث ذﻟﻚ ﺑﺴﺒﺐ اﻟﺮﻳﺎح اﻷﴎع ﻣﻦ اﻟﺼﻮت واﻟﺘﻲ ﺗﺤﺮك اﻟﻬﻮاء اﻟﺴﺎﺧﻦ ﺑﺎﺗﺠﺎه اﻟﴩق .