Free Astronomy Magazine July-August 2025 ARABIC VERSION

Autopsy of planet swallowed by star yields surprise byNASA/ESA/CSA HannahBraun bservations from NASA’s JamesWebbSpaceTelescope haveprovidedasurprising twist in the narrative surrounding what is believed to be the first star observed in the act of swallowing a planet. The new findings suggestthatthestaractuallydidnotswe llto envelop a planet as previously hy- pothesized. Instead, Webb’s obser- vations show the planet’s orbit shrank over time, slowly bringingthe planet closer to its demise until it was engulfed in full. “Becausethisissuchanovelevent, we didn’t quite know what to ex- pectwhenwedecidedtopointthis telescopeinitsdirection,” saidRyan Lau, lead author of the new paper and astronomer at NSF NOIRLab (National Science Foundation Na- tional Optical-Infrared Astronomy Research Laboratory) in Tucson, Ari- zona. “Withitshigh-resolutionlook intheinfrared,wearelearningvalu- ableinsightsaboutthefinalfatesof planetarysystems,possiblyincluding our own.” Two instruments aboard Webbconductedthepost-mortemof the scene – Webb’s MIRI (Mid-In- frared Instrument) and NIRSpec (Near-InfraredSpectrograph). The researchers were able to come to their conclusion using a two- pronged investigative approach. The star at the center of this scene is lo- cated in the Milky Way galaxy about 12,000 light-years away from Earth. The brightening event, formally called ZTF SLRN-2020, was originally spotted as a flash of optical light usingtheZwickyTransientFacilityat Caltech’sPalomarObservatoryinSan Diego, California. Data from NASA’s NEOWISE (Near- EarthObjectWide-fieldInfraredSur- vey Explorer) showed the star actuallybrightenedintheinfrareda year before the optical light flash, hintingatthepresenceofdust.This initial 2023 investigation led re- searcherstobelievethatthestarwas moreSun-like,andhadbeeninthe processofagingintoaredgiant overhundredsofthousandsofyears, slowlyexpandingasitexhaustedits hydrogenfuel. However,Webb’sMIRItoldadiffer- entstory.Withpowerfulsensitivity and spatial resolution, Webb was abletopreciselymeasurethehidden emissionfromthestaranditsimme- diate surroundings, which lie in a very crowded region of space. The researchersfoundthestarwasnotas bright as it should have been if it hadevolvedintoaredgiant,indicat- ing there was no swelling to engulf the planet as once thought. Researchers suggest that, at one point, the planet was about Jupiter- sized, but orbited quite close to the star,evencloserthanMercury’sorbit around our Sun. Over millions of years, the planet orbited closer and closertothestar,leadingtothecat- astrophic consequence. “The planet eventually started to grazethestar’satmosphere.Thenit was a runaway process of falling in fasterfromthatmoment,” saidteam JULY-AUGUST2025 ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 42 ﺗﺤﻠﻴﻞ ﻋﻤﻠ ﺔ ا ﺘﻼع ﻧ ﻢ ﻟ ﻮﻛﺐ ﻜﺸﻒﻋﻦﻣﻔﺎﺟﺄة : ﻘﻠﻢ ﻫﺎﻧﺎ ﺑﺮاون و ﺎﻟﺔ ﻧﺎﺳﺎ و/ ﺎﻟﺔ اﻟﻔﻀﺎء اﻷوروﺑ ﺔ / و ﺎﻟﺔ اﻟﻔﻀﺎء اﻟﻜﻨﺪ ﺔ ﻗـﺪﻣﺖ أرﺻـﺎد ﺗﻠﺴ ـﻜﻮب ﺟــﻴﻤﺲ وﻳ ـﺐ اﻟﻔﻀﺎﺋﻲ اﻟﺘﺎﺑﻊ ﻟ ﻮﻛﺎﻟﺔ ﻧﺎﺳﺎ ﺗﺤﻮﻻً ﻣ ﻔﺎﺟﺌـﺎً ﰲ اﻟﺮواﻳﺔ ا ﺤﻴﻄﺔ ﺑﻤﺎ ﻳ ﻌﺘﻘـﺪ أﻧـﻪ أول ﻧﺠـﻢ ﻳ ﺮﺻﺪ وﻫـﻮ ﻳﺒﺘﻠـﻊ ﻛﻮﻛﺒـﺎً . ﺗﺸـ اﻟﻨﺘـﺎﺋﺞ اﻟﺠﺪﻳـﺪة إﱃ أن اﻟـﻨﺠﻢ ﻟــﻢ ﻳﻨـﺘﻔﺦ ﻟﻴﺤـﻴﻂ ﺑﻜﻮﻛﺐ ﻛﻤﺎ اﻓﱰض ﺳﺎﺑﻘﺎً . ﺑـﺪﻻً ﻣـﻦ ذﻟـﻚ ﺗُﻈﻬﺮ أرﺻﺎد ﺗﻠﺴﻜﻮب وﻳﺐ أن ﻣﺪار اﻟﻜﻮﻛﺐ ﻗﺪ اﻧﻜﻤﺶ ﺑﻤﺮور اﻟﻮﻗﺖ ﻣ ﻤﺎ ﺟﻌﻠـﻪ ﻳﻘـﱰب ﺑﺒﻂء ﻣﻦ ﻧﻬﺎﻳﺘﻪ إﱃ أن اﺑﺘﻠﻌﻪ اﻟﻨﺠﻢ . ﺔﻛﻤﻠ ﺄﺑ ﻧﻈﺮاً " ﻷن ﻫﺬ ا ﺣﺪثٌ ﺟﺪﻳﺪ ﺗﻤﺎﻣﺎً ﻓ ﻠـﻢ ﻧﻜـﻦ ﻧﻌﺮف ﺗﻤﺎﻣ ﺎ ﻣﺎ اﻟﺬي ﻧﺘﻮﻗﻌـﻪ ﻋﻨـﺪﻣﺎ ﻗﺮرﻧـ ﺎ ﺗﻮﺟﻴﻪ اﻟﺘﻠﺴﻜﻮب اﻟﻴﻪ " ﻫﺬا ﻣﺎ ﻗﺎﻟﻪ راﻳﺎن ﻻو ا ﺆﻟﻒ اﻟﺮﺋﻴ ـ ﴘ ﻟﻠﻮرﻗـﺔ اﻟﺒﺤﺜﻴـﺔ اﻟﺠﺪﻳـﺪة وﻋـﺎﻟﻢ اﻟﻔﻠـﻚ ﰲ ﻣﺨﺘـﱪ ﻧـﻮﻳﺮﻻب ) ا ﺨﺘـﱪ اﻟﻮﻃﻨﻲ ﻷﺑﺤﺎث ﻋﻠﻢ اﻟﻔﻠﻚ اﻟﺒ اﻷﺷﻌﺔ و ﴫي ـ ﺗﺤ ـﺖ اﻟﺤﻤــﺮاء اﻟﺘ ـﺎﺑﻊ ﺆﺳﺴ ـﺔ اﻟﻌﻠ ـﻮ م اﻟﻮﻃﻨﻴﺔ ( ﺑ ﰲ ﺗﻮﺳﺎن ﺄرﻳﺰوﻧﺎ . ﺑﻔﻀﻞ ﺻﻮرﺗﻪ ﻋﺎ ﻟﻴﺔ اﻟﺪﻗﺔ ﰲ اﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤـﺮاء ﻧـﺘﻌﻠﻢ رؤىً ﻗﻴ ﻤﺔ ﺣـﻮل ا ﺼـ اﻟﻨﻬـﺎﺋﻲ ﻟﻸﻧﻈﻤـﺔ اﻟﻜﻮﻛﺒﻴﺔ ورﺑﻤﺎ ﺑﻤﺎ ﰲ ذﻟﻚ ﻧﻈﺎﻣﻨـﺎ ". أﺟـﺮى ﺟﻬﺎزان ﻋﲆ ﻣـﺘﻦ ﺗﻠﺴـﻜﻮب وﻳـﺐ ﺗﺤﻠـﻴﻼً ﻟﻠﻤﺸﻬﺪ ﺑﻌﺪ وﻗﻮﻋﻪ وﻫﻤﺎ ﺟﻬﺎز أداة ) ﻣ ي اﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤﺮاء ا ﺘﻮ ( ﺳﻄﺔ وﻣﻄﻴـﺎف اﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤـﺮاء اﻟﻘﺮﻳﺒـﺔ ) ﻧ ﺳـﺒﻚ .( ﺗﻤﻜﻦ اﻟﺒﺎﺣﺜﻮن ﻣﻦ اﻟﺘﻮﺻﻞ إﱃ اﺳـﺘﻨﺘﺎﺟﻬﻢ ﺑﺎﺳﺘﺨﺪام ﻧﻬﺞ اﺳﺘﻘﺼـﺎﺋﻲ ﺛﻨـﺎﺋﻲ اﻟﺸـﻖ . ﻳﻘﻊ اﻟﻨﺠﻢ ﰲ ﻣﺮﻛﺰ ﻫﺬا ا ﺸﻬﺪ ﰲ ﻣﺠﺮة درب اﻟﺘﺒﺎﻧﺔ ﻋﲆ ﻣﺴﺎﻓﺔ ﺗﺒﻠﻎ ﺣﻮاﱄ 12 أﻟﻒ ﺳـﻨﺔ ﺿﻮﺋﻴﺔ ﻣﻦ اﻷرض . رﺻﺪ ﻫ ﺬا اﻟﺤﺪث اﻟﺴﺎﻃﻊ ا ﻌـﺮوف رﺳـﻤﻴ ﺎً ﺑﺎﺳﻢ ZTF SLRN-2020 ﰲ اﻷﺻﻞ ﺑـﻮﻣﻴﺾ ـ ﺿﻮﺋﻲ ﺑ ﴫي ﺑﺎﺳـﺘﺨﺪام ﻣﻨﺸـﺄة زوﻳﻜـﻲ اﻟﻌــﺎﺑﺮة ﰲ ﻣﺮﺻـﺪ ﺑﺎﻟﻮﻣــﺎر اﻟﺘــﺎﺑﻊ ﻌﻬ ـﺪ ﻛﺎﻟﻴ ﻔﻮرﻧﻴﺎ ﻟﻠﺘﻜﻨﻮﻟﻮﺟﻴـﺎ ﰲ ﺳـﺎن دﻳﻴﻐـﻮ ﰲ ﻛﺎﻟﻴﻔﻮرﻧﻴﺎ . أﻇﻬﺮت ﺑﻴﺎﻧﺎت ﻣﺴﺘﻜﺸﻒ ﻣﺴﺢ اﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤﺮاء واﺳﻊ ا ﺠﺎل ﻟﻸﺟـﺮام اﻟﻘﺮﻳﺒﺔ ﻣﻦ اﻷرض ) ﻧﻴﻮواﻳﺲ ( اﻟﺘﺎﺑﻊ ﻟﻮﻛ ﺎﻟﺔ ﻧﺎﺳﺎ أن اﻟﻨﺠﻢ ﻗﺪ ازداد ﺳـﻄﻮﻋ ﺎً ﰲ اﻷﺷـﻌﺔ ﺗﺤﺖ اﻟﺤﻤﺮ اء ﻗﺒﻞ ﻋﺎم ﻣﻦ وﻣـﻴﺾ اﻟﻀـﻮء اﻟﺒﴫي ﻣﻤﺎ ﻳ ﺸ إﱃ وﺟﻮد اﻟﻐﺒﺎر . ﻗﺎد ﻫﺬا اﻟﺒﺤﺚ اﻷوﱄ اﻟﺬي أُﺟﺮي ﻋـﺎم 2023 اﻟﺒﺎﺣﺜ إﱃ اﻻ ﻋﺘﻘﺎد ﺑﺄن اﻟـﻨﺠﻢ ﻛـﺎن أﺷـﺒﻪ ﺑﺎﻟﺸﻤﺲ وﻛﺎن ﰲ ﻃﻮر اﻟﺸﻴﺨﻮﺧﺔ ﻟﻴﺘﺤـﻮ ل إﱃ ﻧﺠﻢ ﻋﻤﻼ ق ﻋﲆ ﻣـﺪى ﻣﺌـﺎت اﻵﻻف ﻣـﻦ اﻟﺴﻨ وﻳﺘﻤﺪد ﺑﺒﻂء ﺑﻌـﺪ اﺳـ ﺘﻨﻔﺎد وﻗـﻮده اﻟﻬﻴﺪروﺟﻴﻨﻲ . ﻣـﻊ ذﻟـﻚ روى ﺟﻬـﺎز ﻣـ ي وﻳﺐ ﻗﺼـﺔ ﻣﺨﺘﻠﻔـﺔ . ﻓﺒﻔﻀـﻞ ﺣﺴﺎﺳـﻴﺘﻪ اﻟﻔﺎﺋﻘﺔ ودﻗﺘـﻪ ا ﻜﺎﻧﻴـﺔ، ﺗﻤﻜـﻦ وﻳـﺐ ﻣـﻦ ﻋﲆ ﺗﻠﺴﻜﻮب وﻳﺐ ﻗﺼﺔ ﻣﺨﺘﻠﻔـﺔ . ﻓﺒﻔﻀـﻞ ﺣﺴﺎﺳﻴﺘ ﻪ اﻟﻔﺎﺋﻘـﺔ ودﻗﺘـﻪ ا ﻜﺎﻧﻴـﺔ ﺗﻤﻜـﻦ ﺗﻠﺴﻜﻮب وﻳﺐ ﻣﻦ ﻗﻴﺎس اﻻﻧﺒﻌﺎﺛﺎت اﻟﺨﻔ ﻴـﺔ ﻣﻦ اﻟﻨﺠﻢ وﻣﺤﻴﻄﻪ ا ﺒﺎﴍ ﺑﺪﻗﺔ واﻟﺘﻲ ﺗﻘـﻊ ﰲ ﻣﻨﻄﻘﺔ ﻣﻜﺘﻈﺔ ﻟﻠﻐﺎﻳﺔ ﻣﻦ اﻟﻔﻀﺎء . ﻟﻘﺪ وﺟ ﺪ اﻟﺒﺎﺣﺜﻮن أن اﻟﻨﺠﻢ ﻟﻢ ﻳﻜﻦ ﺳﺎﻃﻌ ﺎً ﻛﻤﺎ ﻛﺎن ﻳﻨﺒﻐ ﻲ أن ﻳﻜﻮن ﻟﻮ ﺗﻄـﻮر إﱃ ﻧﺠـﻢ ﻋﻤﻼق ﻣﻤﺎ ﻳﺸ إﱃ ﻋﺪم و ﺟﻮد ﺗﻀﺨﻢ ﻳﺒﺘﻠﻊ اﻟﻜﻮﻛﺐ ﻛﻤﺎ ﻛﺎن ﻳﻌﺘﻘﺪ ﺳﺎﺑﻘ .ﺎً ﻳﺸ اﻟﺒﺎﺣﺜﻮن إﱃ أﻧـﻪ ﰲ ﻣﺮﺣﻠـﺔ ﻣـﺎ ﻛـﺎن اﻟﻜﻮﻛﺐ ﺑﺤﺠﻢ ﻛﻮﻛﺐ ا ﺸﱰي ﺗﻘﺮﻳﺒ ﺎً وﻟﻜﻨﻪ ﻛﺎن ﻳﺪور ﻗﺮﻳﺒ اً ﺟﺪ ﺎً ﻣﻦ اﻟﻨﺠﻢ ﺣﺘـﻰ أﻗـﺮب ﻣﻦ ﻣﺪار ﻋﻄﺎرد ﺣﻮل اﻟﺸـﻤﺲ وﻋـﲆ ﻣـﺪى ﻣﻼﻳ اﻟﺴﻨ دار اﻟﻜﻮﻛﺐ أﻗﺮب ﻓـﺄﻗﺮب إﱃ اﻟﻨﺠﻢ ﻣﻤﺎ أدى إﱃ ﻧﺘﻴﺠﺔ . ﻛﺎرﺛﻴﺔ ﻟﻘﺪ ﺑﺪأ اﻟﻜﻮﻛﺐ ﰲ اﻟﻨﻬﺎ ﻳﺔ ﰲ ﻣﻼﻣﺴﺔ اﻟﻐﻼف اﻟﺠﻮي ﻟﻠﻨﺠﻢ ﺛﻢ ﻛﺎﻧﺖ ﻋﻤﻠﻴـﺔ ﻫـﺮوب ﻣـﻦ اﻟﺴﻘﻮط اﻟﴪﻳﻊ ﻣﻦ ﺗﻠـﻚ اﻟﻠﺤﻈـﺔ وﻏـ ت ﻣﺼ اﻟﻜﻮﻛﺐ إﱃ اﻷﺑﺪ ﺑﺸﻜﻞ دراﻣﺎﺗﻴﻜﻲ ﻛﻤﺎ ﻗﺎل ﻋﻀﻮ اﻟﻔﺮﻳﻖ ﻣﻮرﻏﺎن ﻣﺎﻛﻠﻴﻮد ﻣﻦ ﻣﺮﻛﺰ ﻫﺎرﻓـﺎرد ﺳﻤﻴﺜﺴـﻮﻧﻴﺎن ﻟﻠﻔﻴﺰﻳـﺎء اﻟﻔﻠﻜﻴـﺔ وﻣﻌﻬــﺪ ﻣﺎﺳ ﺎﺗﺸﻮﺳــﺘﺲ ﻟﻠﺘﻜﻨﻮﻟﻮﺟﻴــﺎ ﰲ ﻣﱪﻳﺪج ﻛﺎ ﻣﺎﺳﺎﺗﺸﻮﺳﺘﺲ . ﻳﻮﻟﻴﻮ - ﺃﻏﺴﻄﺲ 2 0 2 5