Free Astronomy Magazine September-October 2024

Dysonsuggestedlookingforatwave- lengths between 8 and 12 microns, one of the best windows (the so- calledN-Band)accessiblebyground- based telescopes (the first infrared space telescope, IRAS, was launched over twenty years later and ob- servedmorethan250,000sourcesat 12, 25, 60, and 100 microns). AccordingtoDyson’sinitialvision,a civilization technologically much more advanced than ours would havethemeanstodirectlytakefrom theplanetsofitssystemallthema- terialneededtobuildasphere.As- signingtothelatteraradiusoftwo astronomicalunitsandathicknessof afewmeters,Dysoncalculatedthat the megastructure could be (theo- retically) built by reconverting the entire mass of a planet as large as Jupiter. It is easy to imagine thatDyson spheresremainedforalongtime nothing more than a bizarre idea, with almost no astronomer even attempting research into them. Nonetheless,inrecentdecades,they have occasionally returned to the fore,thankstothemultiplication of infrared surveys carried out both fromtheground(forexample, 2MASS) and from space (for exam- ple,WISE).Althoughthepurposes of these surveys had nothing to do with the search for alien megastruc- tures, the wealthy databases they helped create could contain tracesof suspicious sources, that is, stars with aninfraredemissionthatistoo ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 7 ﻣﻨﻈــﺮ ﻟﻜـــﺮة دا ﺴــﻮن ﻣﻜﺘﻤﻠـــ ــﺎً . ﺔ ﺗﻘﺮ ﺎﻟﻨﺴـــ ﺔ ﻟــ ـ ـــﺔ ـــﻒ ﻤﻜــﻦ ﻧﻘـــﻞ اﻟﻄﺎﻗــﺔ اﻟﻨ ﻤ ـــﻞ اﻟﻀــ ﻤﺔ اﻻﻓ اﺿـــ ﺔ، ﻟــ ﺲﻣـــﻦ اﻟﻮاﺿــﺢ ﻛ ﻤﻴﻊ اﻟﻤﺘﻐـــ ات ﻟﻬــﺬﻩ اﻟﻬ ﺎ اﻟﻤ ﻤﻌﺔ ﺑﻮاﺳﻄﺔ اﻟﺴﻄﺢ اﻟﺪاﺧﻠﻲ ﻟﻠﻜﺮة إﻟﻰ اﻟ ﻮﻛﺐ اﻷﺻﻠﻲ ﻟﻠﺤﻀﺎرة اﻟ ﻨﺎﺋ ﺔ أو أ ﻀًﺎ إﻟﻰ اﻟﻮﺟﻬﺎت اﻻﺧﺮى ] . ﻧﻴﻞ ﻠ ﻔ [ - ﺳﺒﺘﻤﺒﺮ ﺃﻛﺘﻮﺑﺮ 2 0 2 4 واﻟﺘﻲ اﻗﱰح داﻳﺴﻮن اﻟﺒﺤﺚ ﻋﻨﻬـﺎ ﺑـﺄﻃﻮال ﻣﻮﺟﻴﺔ ﺗﱰاوح ﺑ 8 و 12 ﻣﻴﻜﺮون، واﺣـﺪة ﻣﻦ أﻓﻀﻞ اﻟﻨﻮاﻓﺬ ) ﻣﺎ ﻳﺴـﻤﻰ ﺑــ N-Band ( اﻟﺘـﻲ ﻳﻤﻜــﻦ اﻟﻮﺻـﻮل إﻟﻴﻬــﺎ ﻋـﻦ ﻃﺮﻳـﻖ اﻟﺘﻠﺴــﻜﻮﺑﺎت اﻷرﺿــﻴﺔ ) ﺗــﻢ إﻃــﻼق أول ﺗﻠﺴـﻜﻮب ﻓﻀــﺎﺋﻲ ﻳﻌﻤـﻞ ﺑﺎﻷﺷـﻌﺔ ﺗﺤـﺖ اﻟﺤﻤﺮاء إراس) ( ﺑﻌﺪ أﻛﺜﺮ ﻣﻦ ﻋﴩﻳﻦ ﻋﺎﻣـ ﺎً ورﺻﺪ أﻛﺜﺮ ﻣﻦ 250,000 ﻣﺼﺪر ﰲ 12 ، 25 ، 60 ، 100 (. ﻣﻴﻜﺮون وﻓﻘًﺎ ﻟﺮؤﻳﺔ داﻳﺴﻮن اﻷوﻟﻴﺔ، ﻓﺈن اﻟﺤﻀـﺎرة اﻷﻛﺜﺮ ﺗﻘﺪﻣًﺎ ﻣﻦ اﻟﻨﺎﺣﻴﺔ اﻟﺘﻜﻨﻮﻟﻮﺟﻴـﺔ ﻣـﻦ ﺣﻀﺎرﺗﻨﺎ ﺳﻴﻜﻮن ﻟـﺪﻳﻬﺎ اﻟﻮﺳـﺎﺋﻞ اﻟﻼزﻣـﺔ ﻟﺘﺄﺧﺬ ﻣﺒﺎﴍة ﻣﻦ اﻟﻜﻮاﻛﺐ ﰲ ﻧﻈﺎﻣﻬ ﺎ ﺟﻤﻴﻊ ا ﻮاد اﻟﻼزﻣﺔ ﻟﺒﻨﺎء اﻟﻐﻼف اﻟﺠـﻮي . وﺑـﺮﺑﻂ ﻧﺼﻒ اﻟﻘﻄﺮ اﻷﺧ ﺑـ وﺣـﺪﺗ ﻓﻠﻜﻴﺘـ وﺳﻤﻚ ﺑﻀﻌﺔ أﻣﺘﺎر، ﺣﺴـﺐ داﻳﺴـﻮن أﻧـﻪ ﻳﻤﻜﻦ ﺑﻨﺎء اﻟﻬﻴﻜـﻞ اﻟﻀـﺨﻢ ) ﻧﻈﺮﻳًـﺎ ﻋـﻦ ( ﻃﺮﻳﻖ إﻋﺎدة ﺗﺤﻮﻳﻞ اﻟﻜﺘﻠﺔ اﻟﻜﺎﻣﻠﺔ ﻟﻜﻮﻛـﺐ ﻛﺒ ﻣﺜﻞ ﻛﻮﻛﺐ ا ﺸـﱰي . ﻣـﻦ اﻟﺴـﻬﻞ أن ﻧﺘﺨﻴﻞ أن ﻣﺠﺎﻻت داﻳﺴﻮن ﻟـﻢ ﺗﻜـﻦ ﺗﺮﻛـﺰ ﻟﻔﱰة ﻃﻮﻳﻠﺔ إﻻ ﻋﲆ ﻓﻜﺮة ﻏﺮﻳﺒﺔ، ﻣﻊ ﻋـﺪم ﻗﻴﺎم أي ﻓﻠﻜﻲ ﺗﻘﺮﻳﺒًﺎ ﺑﻤﺤﺎوﻟﺔ اﻟﺒﺤﺚ ﻓﻴﻬﺎ . ﻟﻔﱰة ﻃﻮﻳﻠﺔ إﻻ ﻋﲆ ﻓﻜﺮة ﻏﺮﻳﺒﺔ، ﻣﻊ ﻋـﺪم ﻗﻴﺎم أي ﻓﻠﻜﻲ ﺗﻘﺮﻳﺒًﺎ ﺑﻤﺤﺎوﻟﺔ اﻟﺒﺤﺚ ﻓﻴﻬـﺎ وﻣﻊ ذﻟﻚ ﻓﻘﺪ ﻋﺎدت ﰲ اﻟﻌﻘﻮد اﻷﺧـ ة ﻣـﻦ ﺣ ﻵﺧﺮ إﱃ اﻟﻮاﺟﻬﺔ وذﻟﻚ ﺑﻔﻀﻞ ﺗﻀـﺎﻋﻒ ﻋﻤﻠﻴﺎت ا ﺴﺢ ﺑﺎﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤﺮاء اﻟﺘـﻲ ﺗﻢ إﺟ ﺮاؤﻫﺎ ﻣﻦ اﻷرض ) ﻣﺜﻞ ﻣﺴﺢ 2MASS ( وﻣـﻦ اﻟﻔﻀـﺎء ) ﻋـﲆ ﺳـﺒﻴﻞ ا ﺜـﺎل ﻣﻬﻤـﺔ اﻟﺘﻠﺴﻤﻤﻮب اﻟﺘﻠﺴـﻜﻮب اﻳـﺲو " " وﻋـﲆ اﻟـﺮﻏﻢ ﻣـﻦ أن أﻏﺮاض ﻫﺬه ا ﺴﻮﺣﺎت ﻟﻢ ﻳﻜﻦ ﻟﻬﺎ أي ﻋﻼﻗﺔ ﺑﺎﻟﺒﺤﺚ ﻋﻦ اﻟﻬﻴﺎﻛﻞ اﻟﻀﺨﻤﺔ اﻟﻐﺮﻳﺒﺔ ﻓـﺈن ﻗﻮاﻋــﺪ اﻟﺒﻴﺎﻧـﺎت اﻟﻐﻨﻴـﺔ اﻟﺘـﻲ ﺳـﺎﻋﺪت ﰲ إﻧﺸﺎﺋﻬﺎ ﻳﻤﻜﻦ أن ﺗﺤﺘﻮي ﻋﲆ آﺛـﺎر ﺼـﺎدر ﻣﺸﺒﻮﻫﺔ أي ﻧﺠﻮم ذات اﻧﺒﻌﺎث ﻟﻸﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤﺮاء اﻟﺘﻲ ﺗﻜـﻮن وﻓـ ة ﺟـﺪًا ﺑﺎﻟﻨﺴـﺒﺔ ـــــ اﻟﻄ ﻒ اﻟ ﻬﺮوﻣﻐﻨﺎﻃ ﺴﻲ ﻣﻊ ﺗﺴﻠ ﻂ اﻟﻀﻮء ﻋﻠﻰ اﻟﻤﻨﻄﻘﺔ اﻟﻔﺮﻋ ﺔ ﺗﺸﻤﻞ اﻷﺷﻌﺔ ﺗﺤﺖ اﻟ اﻟ ـ ﻤﺮاء اﻟﻤﺘﻮﺳﻄﺔ واﻟ ﻌ ﺪة ] . ﺷﺒ ﺎت اﻟﺘﻜﻨﻮﻟﻮﺟ ﺎ [