Free Astronomy Magazine September-October 2024

abundant for their spectral class or stars with unusual photometric be- havior if the hypothetical megas- tructures were not complete shells. Something of the sort hit the head- lines in 2015, when one of the stars monitored by the Kepler Space Tel- escope, KIC 8462852 (better known as Tabby’s Star), showed brightness fluctuations consistent with a large massorbitingaroundit.Carefulfol- low-upobservationsthenruledout anexcessofinfraredradiation,lead- ing astronomers to lean towards a natural cause of the phenomenon, such as an inhomogeneous circum- stellardiskofrockydebrisandice, or, alternatively, intrinsic variations in the stellar photosphere. The disappearance of the most promising Dyson sphere candidate hasobviouslynotdiscouragedthe mostassiduoushuntersofthosehy- pothetical engineering works. In recent years, there has been no shortage of contributions from ex- pert research teams, such as Project Hephaistos(anameinspiredbythe Greekgodoffire,forges,engineer- ing, sculpture, and metallurgy), whichisbasedatUppsalaUniversity, Sweden, and has collaborators in theUSA,UK,andIndia.Themostre- cent contribution from ProjectHephaistos,en- titled “Dyson sphere candidates from Gaia DR3,2MASS,andWISE,” was published in the Monthly Notices of the RoyalAstronomicalSoci- ety last June by a team including lead author Matías Suazo (Depart- ment of Physics and As- tronomy, Uppsala Uni- versity). The team used the im- pressive databases of those three surveys, searching for astrophys- ical objects with spec- tral,photometric,and ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 8 ﻟﻔﺌﺘﻬـﺎ اﻟﻄﻴﻔﻴـﺔ أو اﻟﻨﺠـﻮم ذات اﻟﺴـﻠﻮك اﻟﻀـﻮﺋﻲ ﻏــ ا ﻌﺘ ـﺎد إذا ﻛﺎﻧــﺖ اﻟﻬﻴﺎﻛ ـﻞ اﻟﻀﺨﻤﺔ اﻻﻓﱰاﺿﻴﺔ ﻟﻢ ﺗﻜﻦ ﻛـﺮات . ﻛﺎﻣﻠـﺔ ﳾء ﻣﻦ ﻫﺬا اﻟﻘﺒﻴﻞ ﺗﺼﺪر ﻋﻨﺎوﻳﻦ اﻷﺧﺒﺎر ﰲ ﻋﺎم 2015 ، ﻋﻨﺪﻣﺎ أﻇﻬﺮ أﺣﺪ اﻟﻨﺠﻮم اﻟﺘﻲ ﺗﻢ رﺻ ﺪﻫﺎ ﺑﻮاﺳﻄﺔ ﺗﻠﺴﻜﻮب ﻛﻴﺒﻠﺮ اﻟﻔﻀـﺎﺋﻲ KIC 8462852 ) ا ﻌﺮوف ﺑﺎﺳﻢ ﻧﺠﻢ ﺗـﺎﺑﻲ ( ﺗﻘﻠﺒﺎت ﰲ اﻟﺴﻄﻮع ﺗﺘﻮاﻓﻖ ﻣﻊ ﻣـﺪار ﻛﺘﻠـﺔ ﻛﺒ ﺣﻮﻟﻪ . ﻟﻘﺪ أدت أرﺻﺎد ا ﺘﺎﺑﻌﺔ اﻟﺪﻗﻴﻘﺔ ــ ﻣﻦ ﺧﻼل ﺑﺮاﻣﺞ ا ﺴﺢ ﻏﺎﻳـﺎ DR3 و واﻳﺲ و , 2MASS وﻗـﺪ ﺗ ـﻢ ﻧ ـ ﺎﴩﻫ ـ ﰲ اﻹﺷـﻌﺎرات اﻟﺸﻬﺮﻳﺔ ﻟﻠﺠﻤﻌﻴـﺔ اﻟﻔﻠﻜﻴـﺔ ا ﻠﻜﻴﺔ ﰲ ﻳﻮﻧﻴﻮ ا ـﺎﴈ ﻣـﻦ ﻗﺒــﻞ ﻓﺮﻳــﻖ ﻳﻀــﻢ ا ﺆﻟــﻒ اﻟﺮﺋﻴـ ـ ﴘ ﻣﺎﺗﻴـﺎسﺳـﻮازو ) ﻗﺴﻢ اﻟﻔ ﻴﺰﻳﺎء وﻋﻠﻢ اﻟﻔﻠﻚ ﰲ ﺟﺎﻣﻌﺔ أوﺑﺴﺎﻻ .( اﺳــﺘﺨﺪم اﻟﻔﺮﻳــﻖ ﻗﻮاﻋــﺪ اﻟﺒﻴﺎﻧـــﺎت اﻟﻬﺎﻣـــﺔ ﻟﺘﻠـــﻚ ا ﺴﻮﺣﺎت اﻟﺜﻼﺛﺔ ﻟﻠﺒﺤﺚ ﻋﻦ اﻻﺟﺮام اﻟﻔﻴﺰﻳﺎﺋﻴـﺔ اﻟﻔﻠﻜﻴـﺔ ذات اﻟﻘﻴﺎﺳـــﺎت اﻟﻄﻴﻔﻴـــﺔ اﻟﻀــــﻮﺋﻴ ﺔ وﺧﺼــــﺎﺋﺺ إﱃ اﺳﺘﺒﻌﺎد إﺷﻌﺎﻋﺎت اﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤﺮاء اﻟﺰاﺋﺪة، ﻣﻤﺎ دﻓﻊ ﻋﻠﻤﺎء اﻟﻔﻠﻚ إﱃ ا ﻴﻞ ﻧﺤـﻮ اﻟﺴﺒﺐ اﻟﻄﺒﻴﻌﻲ ﻟﻬﺬه اﻟﻈﺎﻫﺮة ﻣﺜـﻞ وﺟـﻮد ﻗﺮص ﻧﺠﻤﻲ ﻣﺘﺠﺎﻧ ﺲ ﻣﻜﻮن ﻣـﻦ اﻟﺤﻄـﺎم اﻟﺼﺨﺮي واﻟﺠﻠﻴﺪ أو ﺑﺪﻻً ﻣﻦ ذﻟﻚ اﻻﺧﺘﻼﻓﺎت اﻟﺠﻮﻫﺮﻳﺔ ﰲ اﻟﻐﻼف ا ﻟﻀﻮﺋﻲ اﻟﻨﺠﻤﻲ وﻣـﻦ اﻟﻮاﺿﺢ أن اﺧﺘﻔﺎ ء ﻛﺮة داﻳﺴﻮن اﻟﻮاﻋﺪ ة ﻟـﻢ ﻳﺜﺒﻂ ﻫﻤﺔ اﻟﺒﺎﺣﺜ اﻷﻛﺜﺮ ﻣﺜﺎﺑﺮة ﻋـﻦ ﺗﻠـﻚ اﻷﻋﻤﺎل اﻟﻬﻨﺪﺳﻴﺔ اﻻﻓﱰاﺿﻴﺔ . ﰲ اﻟﺴﻨﻮات اﻷﺧ ة، ﻟﻢ ﻳﻜﻦ ﻫﻨﺎك ﻧﻘـﺺ ﰲ ا ﺴﺎﻫﻤﺎت ﻣﻦ ﻓﺮق اﻟﺒﺤﺚ ا ﺘﺨﺼﺼﺔ، ﻣﺜﻞ ﻣﴩوع ﻫﻴﻔﺎﻳﺴﺘﻮس ) وﻫﻮ ﻟﻌﺒﺔ ﻣﺴﺘﻮﺣﺎة ﻣﻦ إﻟﻪ اﻟﻨﺎر وا ﺼـﺎﻳﺪ واﻟﻬﻨﺪﺳـﺔ واﻟﻨﺤـﺖ وا ﻌﺎدن ﻋﻨﺪ اﻟﻴﻮﻧـﺎﻧﻴ ( ، وﻣﻘـﺮه ﺟﺎﻣﻌـﺔ أوﺑﺴﺎﻻ ، اﻟﺴﻮﻳﺪ . وﻟﻬﺎ ﻣﺘﻌﺎوﻧﻮن ﰲ اﻟﻮﻻﻳﺎت ا ﺘﺤﺪة اﻷﻣﺮﻳﻜﻴﺔ وا ﻤﻠﻜﺔ ا ﺘﺤـﺪة واﻟﻬﻨـﺪ . إن أﺣ ــﺪث ﻣﺴ ــﺎﻫﻤﺔ ﻣ ــﻦ ﻣ ــ وع ﴩ ـ ﻫﻴﻔﺎﻳﺴـﺘﻮس، ﺑﻌﻨ ـﻮان " ﻣﺮﺷـﺤﻮ ﻛ ـﺮات ــــــ ﺗﻈﻬـــــــــﺮ ﻫــــــــــﺬﻩ اﻟﺮﺳــــــــــﻮم ﺳــــــــــــــــــ ﻨﺎر ﻣﺤﺘﻤﻠـــــــــــــــــــ ﻮﻫ ﻟﻠﺴـــــﻠﻮك اﻟﻀـــــﻮﺋﻲ ا ﻟﻐﺮ ــــــﺐ ﻟ ﻠﻨ ﻢ KIC8462852 وﻫﻮ ـــــﻢ ﻣـــــﻦ اﻟﻨﺴـــــﻖ اﻟﺮ ﺴـــــﻲ ﻧ ) اﻟﻨــــــــــــــﻮع F ( ــــــــــــــﺔ ﻓــــــــــــــﻲ ﻮﻛ اﻟﺪﺟﺎﺟـــــــــــﺔ ﻋﻠـــــــــــﻰ ﻣﺴـــــــــــﺎﻓﺔ ﺣــــﻮاﻟﻲ 1500 ﺳــــﻨﺔ ﺿــــﻮﺋ ﺔ ﻣــــــﻦ اﻷرض و ﻟﻔــــــ ة ﻗﺼــــــ ة ﺎن ﻫﺬا اﻟ ـ ﺠﺴﻢ ﻣﺮﺷﺤﺎ ﻷن ـــــﻮن ﻛـــــﺮة دا ﺴـــــﻮن ﻳ وﻟﻜـــــﻦ ـــــــﺎن ـــــــﺢ أن اﻟـــــــﻨ ﻢ ﻣـــــــﻦ اﻷرﺟ ــــــــــــﺎ ﺑﻮاﺳــــــــــــﻄﺔ ـــــــــــﺎ ﺟﺰ ﻣﺤﺠﻮ ﺗ ﻤﻊ ﻣﻦ اﻟﻤﺬﻧ ﺎت أو ﻗﺮص ـ ﻣـــﻦ اﻟـــ ﺤﻄﺎم ذو ﻛﺜﺎﻓـــﺔ ﻏـــ . ﻣﻨﺘﻈﻤﺔ ] NASA, JPL-Caltech [ - ﺳﺒﺘﻤﺒﺮ ﺃﻛﺘﻮﺑﺮ 2 0 2 4