Free Astronomy Magazine March-April 2026 ARABIC VERSION

MARCH-APRIL2026 A n emission spectrum captured by NIRSpec (the Near-Infrared Spectrograph) on NASA’s James Webb Space Telescope in May 2024 shows the brightness of different wavelengths of 3- to 5-mi- cron light coming from the ultra-hot super-Earth exoplanet TOI-561 b. Comparisons of the data to theoretical models suggest that the planetisnotabarerock,butisinsteadsurroundedbyavolatile-rich atmosphere. The data (white circles) are based on measurements of the change in brightness of the star-planet system before, during, and after the secondary eclipse, when the planet moves behind the star. Although TOI-561 b is too close to the star to see on its own, the amount of light coming from the planet can be calculated by subtracting the brightness of the star (measured when the planet is behind the star) from the brightness of the planet and star com- bined (measured when the planet is beside the star). TOI-561 b is thought to be tidally locked, which means that most of the plane- tary light measured during this observation is coming from the day- side. Three model spectra are shown for comparison. If TOI-561 b has a dark bare-rock surface with no atmosphere (smooth gray line),orathinrock-vaporatmosphere(jaggedpurpleline),thedaysideoftheplanetshouldappearsignificantlybrighterthanitactuallydoes. Instead, the data are much more consistent with an atmosphere rich in volatiles like water, oxygen, and carbon dioxide. (The model shown here assumes an atmosphere that is 100% water vapor.) A thick volatile-rich atmosphere absorbs some of the near-infrared light emitted by the surface, which reduces the amount that reaches the telescope. This makes the planet appear dimmer than it would with no atmosphere ora very thin layer or vaporized rock. A thick atmosphere also acts to distribute heat around the planet via winds, cooling the dayside and heat-ing the nightside. Webb observed the TOI-561 system continuously for more than 37 hours, capturing nearly four full orbits, including four consecutive secondary eclipses. [NASA, ESA, CSA, Ralf Crawford (STScI); Science: Johanna Teske (Carnegie Science Earth and Planets Labora-tory), Anjali Piette (University of Birmingham), Tim Lichtenberg (Groningen), Nicole Wallack (Carnegie Science Earth and Planets Laboratory)] anyatmosphereatall,letaloneone sosubstantial?Somegasesmustbe escaping to space, but perhaps not asefficientlyasexpected. “Wethinkth ereisanequilibriumbetweenthe magmaoceanandtheatmosphere. Atthesametimethatgasesarecom- ingoutoftheplanettofeedtheat- mosphere,themagmaoceanissuck- ingthembackintotheinterior,” said co-author Tim Lichtenberg from the University of Groningen in the Ne- therlands. “Thisplanetmustbemuch,mu ch more volatile-rich than Earth toexplaintheobservations.It’sreally like a wet lava ball.” These are the first results from Webb’sGeneralObserversProgram 3860,whichinvolvedobservingthe systemcontinuouslyformorethan 37hourswhileTOI-561bcompleted nearly four full orbits of the star. Theteamiscurrentlyanalyzingthe fulldatasettomapthetemperature all the way around the planet and narrowdownthecompositionofthe atmosphere. “What’sreallyexcitingis thatthisnewdatasetisopening up even more questions than it’s an- swering,” saidTeske. ■ ﻗﺎل ا ﺆﻟـﻒ ا ﺸـﺎرك ﺗـﻴﻢ ﻟﻴﺸـﺘﻨﱪغ ﻣـﻦ ﺟﺎﻣﻌﺔ ﺟـﺮوﻧﻴﻨﺠﻦ ﰲ ﻫﻮﻟﻨـﺪا .» ﻧﻌﺘﻘـﺪ أن ﻫﻨﺎك ﺗﻮازﻧﺎً ﺑ ﻣﺤﻴﻂ اﻟﺼﻬﺎرة واﻟﻐـﻼف اﻟﺠﻮي . ﰲ اﻟﻮﻗﺖ اﻟﺬي ﺗﻨﻄﻠﻖ ﻓﻴﻪ اﻟﻐـﺎزات ﻣــﻦ اﻟﻜﻮﻛــﺐ ﻟﺘﻐﺬ ﻳــﺔ اﻟﻐ ـﻼف اﻟﺠ ـﻮي، ﻳﺴﺤﺒﻬﺎ ﻣﺤﻴﻂ اﻟﺼﻬﺎرة إﱃ داﺧﻠـﻪ « ، ﻫـﺬا ﻣﺎ ﻗﺎﻟﻪ ا ﺆﻟﻒ ا ﺸﺎرك ﺗﻴﻢ ﻟﻴﺸـﺘﻨﱪغ ﻣـﻦ ﺟﺎﻣﻌﺔ ﺟـﺮوﻧﻴﻨﺠﻦ ﰲ ﻫﻮﻟﻨـﺪا .» ﻳﺠـﺐ أن ﻳﻜﻮن ﻫـﺬا اﻟﻜﻮﻛـﺐ أﻏﻨـﻰ ﺑﻜﺜـ ﺑـﺎ ﻮاد ا ﺘﻄــﺎﻳﺮة ﻣــﻦ اﻷرض ﻟﺘﻔﺴــ ﻫــﺬه ا ﺘﻄﺎﻳﺮة ﻣﻦ اﻷرض ﻟﺘﻔﺴ ﻫﺬه اﻷرﺻﺎد . إﻧﻪ ﻳﺸﺒ ﻪ ﻛﺮة ﻣﻦ اﻟﺤﻤﻢ اﻟﱪﻛﺎﻧﻴﺔ اﻟﺮﻃﺒـﺔ و ﻫــﺬه ﻫ ـﻲ اﻟﻨﺘ ـﺎﺋﺞ اﻷوﱃ ﻣ ـﻦ ﺑﺮﻧــﺎﻣﺞ اﻟﺮاﺻﺪﻳﻦ اﻟﻌﺎﻣ ﻟﺘﻠﺴﻜﻮب ﺟﻴﻤﺲ وﻳـﺐ اﻟﻔﻀـﺎﺋﻲ 3860 واﻟ ـﺬي ﺗﻀـﻤﻦ ﻣﺮاﻗﺒ ـﺔ اﻟﻨﻈﺎم ﺑﺸﻜﻞ ﻣﺴﺘﻤﺮ ﻷﻛﺜﺮ ﻣﻦ 37 ﺳـﺎﻋﺔ ﺑﻴﻨﻤﺎ أﻛﻤﻞ اﻟﻜﻮﻛﺐ TOI-561 b ﻣﺎ ﻳﻘـﺮب ﻣﻦ أرﺑﻊ دورات ﻛﺎﻣﻠﺔ ﺣﻮل اﻟـﻨﺠﻢ . ﻳﻘـﻮم اﻟﻔﺮﻳﻖ ﺣﺎﻟﻴﺎً ﺑﺘﺤﻠﻴـﻞ ﻣﺠﻤﻮﻋـﺔ اﻟﺒﻴﺎﻧـﺎت اﻟﻜﺎﻣﻠﺔ ﻟﺮﺳﻢ ﺧﺮﻳﻄﺔ ﻟﺪرﺟﺔ اﻟﺤﺮارة ﺣﻮل اﻟﻜﺎﻣﻠﺔ اﻟﺤﺪﻳﺜﺔ ﻋﺎﻟﻴﺔ اﻟﺪﻗﺔ ﻟﺮﺳﻢ ﺧﺮﻳﻄﺔ ﻟﺪرﺟﺔ اﻟﺤﺮارة ﺣﻮل ﻫﺬا اﻟﻜﻮﻛﺐ ﺑﺎﻟﻜﺎﻣـﻞ و ﺗﺤﺪﻳﺪ ﺗﺮﻛﻴﺒﺔ اﻟﻐﻼف اﻟﺠﻮي ﺑﺪﻗﺔ أﻛﱪ . إن ﻫﺬه اﻟﺠﻬﻮد اﻟﺒﺤﺜﻴﺔ ﺗﻬـﺪف إﱃ ﻛﺸـﻒ اﻷﴎار اﻟﺪﻓﻴﻨﺔ ﻣﻤﺎ ﻳﻤﻬـﺪ اﻟﻄﺮﻳـﻖ ﻟﻔﻬـﻢ أﻋﻤﻖ ﻟﻨﺸﻮء اﻟﻌﻮاﻟﻢ اﻟﺒﻌﻴﺪة . ﻗﺎل ﺗﻴﺴﻜﻲ : " اﻷﻣﺮ ا ﺜ ﺣﻘﺎً ﻫﻮ أن ﻫﺬه ا ﺠﻤﻮﻋﺔ اﻟﺠﺪﻳﺪة ﻣﻦ اﻟﺒﻴﺎﻧﺎت ﺗﻔﺘﺢ أﺳﺌﻠﺔ أﻛﺜﺮ ﻣﻤﺎ ﺗﺠﻴﺐ ﻋﻠﻴﻪ ". - ﻣﺎﺭﺱ ﺃﺑﺮﻳﻞ 2 0 2 6 ــﻒ ﻃ اﻧ ﻌــﺎث اﻟ ﺘﻘﻄــﮫ ﺟﻬـــﺎز ﻧ ﺴــﻚ ) ــﺔ ــﺎف اﻷﺷــﻌﺔ ﺗﺤـــﺖ ا ﻤــﺮاء اﻟﻘﺮ ﻣﻄ ( ﻋﻠــﻰ ﻣـــ ـﺐ اﻟﻔﻀـﺎﺋﻲ اﻟﺘـﺎﺑﻊ ﻟﻨﺎﺳـﺎ ﻓـﻲ ﻣـﺎﻳﻮ ﺗﻠﺴـ ﻮبﺟـ ﻤﺲو 2024 ــﺔ ﻈﻬـﺮﺳـﻄﻮع أﻃـﻮال ﻣﻮﺟ ﻣﺨﺘﻠﻔﺔ ﻣﻦ 3 إﻟﻰ 5 ﻣ ﻜﺮون ﻣﻨ ﻌﺜﺔ ﻣـﻦ اﻟ ﻮﻛـﺐ اﻟـ ـ ﺨﺎرﺟﻲﻓـﺎﺋﻖ اﻟـ ـ ﺤﺮارة TOI-561 b . ﺗﺸـ ﻣﻘﺎر ـﺎت اﻟﺒ ﺎﻧــﺎت ﻣـﻊ اﻟﻨﻤــﺎذج اﻟﻨﻈﺮ ـﺔ إﻟـﻰ أن اﻟ ﻮﻛـﺐ ﻟــ ﺲﺻـﺨﺮة ﺟـﺮداء ﺑـﻞ ﻣﺤــﺎط ﻐــﻼف ــﺎﻟﻤﻮاد اﻟﻤﺘﻄــﺎﻳﺮة ﺟــﻮيﻏــ . ﺗﺴــﺘﻨﺪ اﻟﺒ ﺎﻧــﺎت ) اﻟــﺪواﺋﺮ اﻟﺒ ﻀــﺎء ( إﻟـﻰﻗ ﺎﺳــﺎت ﺗﻐــ ﺳــﻄﻮع ﻧﻈﺎم اﻟﻨ ﻢ واﻟ ﻮﻛﺐ ﻗﺒﻞ وأﺛﻨﺎء و ﻌﺪ اﻟـﺨﺴﻮف اﻟﺜﺎﻧﻮي ﻋﻨﺪﻣﺎ ﺘﺤﺮك اﻟ ﻮﻛﺐﺧﻠﻒ اﻟﻨ ﻢ . ﻋﻠﻰ اﻟﺮﻏﻢ ﻣﻦ أن اﻟ ﻮﻛﺐ TOI-561 b ﻗﺮ ﺐﺟـﺪ اً ـﺚ ﻻ ﻣـﻦ اﻟـﻨ ﻢ ﺑﺤ ﻤﻜـﻦ ر ؤ ﺘـﮫ ﻤﻔـﺮدﻩ إﻻ ـﺔ اﻟﻀـﻮء اﻟﻘﺎدﻣـﺔ ﻣﻨـﮫ ﻋـﻦ ﻃﺮ ـﻖﻃـﺮحﺳـﻄﻮع اﻟـﻨ ﻢ أﻧﮫ ﻤﻜـﻦﺣﺴـﺎب ﻤ ) اﻟﻤﻘـﺎسﻋﻨـﺪﻣﺎ ﻳ ﻮن اﻟ ﻮﻛﺐ ﺧﻠﻒ اﻟـﻨ ﻢ ( ﻣـﻦﺳـﻄﻮع اﻟ ﻮﻛـﺐ واﻟـﻨ ﻢ ﻣﻌـ ) ﺎً اﻟﻤﻘـﺎسﻋﻨـ ـﻮن اﻟ ﻮﻛـﺐ ﺪﻣﺎ ﻳ ﺑﺠﺎﻧﺐ اﻟﻨ ﻢ .( ﻌﺘﻘﺪ أن اﻟ ﻮﻛﺐ TOI-561 b ﻣﻘ ﺪ ﻣـﺪ ﺎً أن ﻣﻌﻈـﻢﺿـﻮء اﻟ ﻮﻛـﺐ ﻣﻤـﺎ ﻌـ اﻟﻤ ﻘـــﺎسﺧـــﻼل ﻫـــﺬﻩ اﻟ ـــﮫ اﻟﻨﻬـــﺎري ـــﺄﺗﻲ ﻣــــﻦ ﺟﺎﻧ ﻤﻼﺣﻈـــﺔ ﺗ. ــــﺔ ـــﺎف ﻧﻤﻮذﺟ ﻌـــﺮض ﺛﻼﺛـــﺔ أﻃ ﻟﻠﻤﻘﺎرـــﺔ . ـــﺎن ﻟﻠ ﻮﻛـــﺐ إذا TOI-561 b ﺳـــﻄﺢ ﺻـــﺨﺮيداﻛـــﻦ ﻋـــﺎرٍ ـــﺪون ﻏـــﻼفﺟـــﻮي ﺧـــﻂ ) أﻣﻠـــــﺲ رﻣـــــﺎد ( أو ﻏـــــﻼفﺟـــــﻮي رﻗﻴـــــﻖ ﻣـــــ ﻦ ﺑﺨـــــﺎر اﻟﺼـــــﺨﻮر ) ﺧـــــﻂ ﻨﻔﺴـــــﺠﻲﻣﺘﻌـــــﺮج ( ﻓﻤـــــﻦ اﻟﻤﻔـــ ض أن ﻈﻬـــﺮ اﻟـــ ـ ﺠﺎﻧﺐ اﻟﻨﻬـــﺎريﻣـــﻦ اﻟ ﻮﻛـــﺐ أﻛـــ ﺳـــ ﺎً ﻮﻋﻄ ﻜﺜـــ ﻣﻤـــﺎ ﻫـــ ـــﮫ ﻓـــﻲ ﻮ ﻋﻠ اﻟﻮاﻗــﻊ . ــﺪﻻً ﻣــﻦ ذﻟــﻚ ــﺎﻟﻤﻮاد اﻟﻤﺘﻄــﺎﻳﺮة ﺗﺘﻮاﻓــﻖ اﻟﺒ ﺎﻧــﺎت ﺸــ ﻞ أﻛــ ﻣــﻊ ﻏــﻼفﺟــﻮيﻏــ ــــــــــــــــــــــــــــــــــــــــــــــــــــ وﺛـﺎﻧﻲ أﻛﺴـ ﺪ اﻟﻜﺮ ﻣﺜـﻞ اﻟﻤـﺎء واﻷﻛﺴـﺠ ـﻮن ) . ﻔـ ض اﻟﻨﻤـﻮذج اﻟﻤﻮﺿـﺢ ﻫﻨـﺎ أن اﻟﻐـﻼف اﻟــ ـ ـﻮن ﻣـﻦ ﺑﺨـﺎرﻣـﺎء ﻨﺴـ ﺔ ﺠﻮي ﺘ 100 .(% ﻤــﺘﺺ اﻟﻐـﻼف اﻟـ ـ ـﺎﻟ ﺠﻮي اﻟﺴـﻤ ﻚ اﻟﻐـ ﻤﻮاد اﻟﻤﺘﻄــﺎﻳﺮة ﺟﺰء ا ﻣﻦ ﺿﻮء اﻷﺷﻌﺔ ﺗﺤﺖ اﻟ ـ ﻤﺮاء اﻟﻘﺮ ﺔ اﻟﻤﻨ ﻌﺚ ﻣﻦ اﻟﺴﻄﺢ ﻣﻤﺎ ﻘﻠﻞ ﺗﺼﻞ إﻟﻰ اﻟﺘﻠﺴ ﻮب وﻫﺬا ﻳﺠﻌﻞ اﻟ ﻮﻛﺐ ﻳ ﺪو أﻗﻞﺳﻄﻮ ﻣﻦ اﻟ ﻤ ﺔ اﻟ ﺎً ﻋ ﻣﻤﺎ ﻟﻮ ﻟـﻢ ﻜـﻦ ﻟـﮫ ﻏـﻼف ـﺎن ﺟـﻮي أو ﻟـﻮ ﻟﮫ ﻃ ﻘﺔ رﻗ ﻘﺔ ﺟﺪ اً ﻣﻦ اﻟﺼﺨﻮر اﻟﻤﺘﺒﺨﺮ . ة ﻤﺎ ﻌﻤﻞ اﻟﻐﻼف اﻟ ـ ﺠﻮي اﻟﺴﻤ ﻚ ﻋﻠﻰ ﺗﻮز ﻊ اﻟ ـ ﺤﺮارة ﺣﻮل اﻟ ﻮﻛﺐ ﻋ اﻟﺮ ﺎح ﻣﻤﺎ ﻳ د اﻟ ـ ﺠﺎﻧﺐ اﻟﻨﻬﺎريو ﺴﺨﻦ اﻟ ـ ﺠﺎﻧﺐ اﻟﻠ ﻠﻲ وﻳﺆﺛﺮذﻟﻚﻓﻲ اﻟﺘ ﺎﻳﻦ اﻟـﺤﺮاري و ﻌﺪل اﻟ ﺼﻤﺔ اﻟﻄ ﻔ ﺔ و ﻐ ﺗﻘﺪ ـ ﻳﺮاﻟ ﺨﺼﺎﺋﺺ اﻟﻔ ﺎﺋ ﺔ اﻟﺪﻗ ﻘﺔ ﻟﺴﻄﺤﮫ و ﻨ ﺘﮫ اﻟﻜ ﻤ ﺎﺋ ﺔ وﺗﺮﻛﻴ ﮫ اﻟﻤﺤﺘﻤﻞ ﻟﻘﺪ . رﺻﺪ ﺗﻠﺴ ﻮبﺟ ﻤﺲو ﺐ ﻧﻈﺎم TOI-561 ﺸ ﻞ ﻣﺴﺘﻤﺮ ﻷﻛـ ﻣـﻦ 37 واﻟ ﺳﺎﻋﺔ ﺘﻘﻂﻣﺎ ﻘﺮ ﻣﻦ أرﻊ دورات ﺎﻣﻠﺔ ﻤﺎ ﻓﻲذﻟﻚ أر ﻊ ﻛﺴﻮﻓﺎت ﺛﺎﻧﻮ ﺔ ﻣﺘﺘﺎﻟ ﺔ أﺗﺎح ﻣﺎ ﻗ ﺎس اﻟﺘ ﺎﻳﻦ اﻟـﺤﺮاريوﺗﺤﺪ ﺪ ﺧﺼﺎﺋﺺ اﻟﻐ ﻼف اﻟـﺠﻮي ﺪﻗﺔ ﻋﺎﻟ ﺔ ﻏ ﻣﺴﺒﻮﻗﺔ . [NASA, ESA, CSA, Ralf Crawford (STScI); Science: Johanna Teske (Carnegie Science Earth and Planets Laboratory), Anjali Piette (University of Birmingha ), Tim Lichtenberg (Groningen), Nicole Wallack (Carnegie Science Earth a d Planets Laboratory)]