Free Astronomy Magazine July-August 2022 ARABIC VERSION

A Dyson sphere pictured here, megastructure, such as the would be capable of generating tech- nosignatures visible at great distances in the galaxy, revealing the presence of an alien technological civilization even in the absence of radio commu- nications. [Capnhack.com] I tion or isotope ratios of sediments, but we could not rule out natural causes behind such anomalies. How- ever, the existence of a previous ter- restrial civilization remains more of a thought experiment than a realis- tic hypothesis. Regardless of the relative abun- dances of the two markers of life in the cosmos, both the search for bio and techno are hampered by the problem of the ambiguity of their recognition. Wright and colleagues highlight two main forms of ambigu- ity: nature and the significance of the detected marker. Biosignatures suf- fer more from this because the po- tentially life-related molecules rec- ognizable today in the atmospheres of planets other than Earth can easily arise from natural processes. Let’s think about the recent cases of methane on Mars or phosphine on Venus. On the other hand, some technosignatures detectable even at great distances, such as very narrow- band radio signals, are decidedly less ambiguous, since no known natural source can generate them. At this point, it is easy to under- stand why astrobiologists prefer to look for an anomalous signal in a large star field that likely contains thousands or millions of planets, rather than struggling to isolate the spectrum of a single planet, looking for molecules that today could not be associated with certainty to the presence of life. In this astrobiolog- ical context, the variants proposed by Wright and colleagues will be nterstellar spacecraft can be de- tectable from hundreds to thou- sands of light years away through various forms of radiation. The aster- oid `Oumuamua (illustrated here) has shown that we can even receive vis- its from objects from other planetary systems. [ESA/Hubble, NASA, ESO, M. Kornmesser] useful in developing the discussion on the implications of some proper- ties of technological life that differ fundamentally from those of non- technological life.   اﻟﻜــﻮن ﻓــﺈن اﻟﺒﺤــﺚ ﻋــﻦ اﻟﺒﺼــﻤﺎت اﳊﻴﻮﻳــﺔ واﻟﺘﻘﻨﻴـﺔ ﺗﻌﻮﻗﻬﻤــﺎ ﻣﺸـﻜﻠﺔ ﻏﻤـﻮض اﻟﺘﻌـﺮف ﻋﻠﻴﻬﻤــﺎ . ﻳﺴــﻠﻂ رأﻳــﺖ وزﻣــﻼؤه اﻟﻀــﻮء ﻋــﲆ ﺷــﻜﻠﲔ رﺋﻴﺴــ ﲔ ﻣــﻦ اﻟﻐﻤــﻮض : اﻟﻄﺒﻴﻌــﺔ ﻴﺔ وأﻫﻤ اﻟﺒﺼﻤﺎت اﳌﻜﺘﺸﻔﺔ . ﺗﻌﺎﱐ اﻟﺒﺼ ﺎت ﻤ اﳊﻴﻮﻳــﺔ أﻛــﱶ ﻣـــﻦ ذﻟــﻚ ﻷن اﳉﺰﻳﺌــﺎت اﻟـــﱵ ﻳﺤﺘﻤﻞ أن ﺗﻜﻮن ﻣﺮﺗﺒﻄـﺔ ﺑﺎﳊﻴـﺎة واﻟـﱵ ﳝﻜـﻦ اﻟﺘﻌــــﺮف ﻋﻠﻴﻬــــﺎ اﻟﻴــــﻮم اﻷﻏﻠﻔــــﺔ اﳉﻮﻳــــﺔ ﻟ ﻠﻜﻮاﻛــــﺐ ﺑﺨــــﻼف اﻷرض ﳝﻜــــﻦ أن ﺗﻨﺸــــﺄ ﺑﺴﻬﻮﻟﺔ ﻣﻦ اﻟﻌﻤﻠﻴﺎت اﻟﻄﺒﻴﻌﻴﺔ دﻋﻮﻧـﺎ ﻧﻔﻜـﺮ ﺑ ﺎﳊـﺎﻻت اﻷﺧـﲑة ﻣـﻦ ﻏـﺎز اﳌﻴﺜــﺎن ﻋـﲆ اﳌـﺮﻳﺦ ﺑﺒ ﺒﺐ ﻣﺜـﻞ ﻫــﺬه اﳊــﺎﻻت اﻟﺸــﺎذة وﻣــﻊ ذﻟــﻚ ﻳﻈــﻞ وﺟـﻮد ﺣﻀـ ﺎرة أرﺿـﻴﺔ ﺳـﺎﺑﻘﺔ ﺗﺠﺮﺑــﺔ ﻓ ﻜﺮﻳـﺔ أﻛـﱶ ﻣـﻦ ﻛﻮﻧﻬـﺎ ﻓﺮﺿـﻴﺔ واﻗﻌﻴـﺔ ﺑﻐـﺾ اﻟﻨﻈـﺮ ﻋــــﻦ اﻟــــﻮﻓﺮة اﻟﻨﺴــــ ﻴﺔ ﻟﻌﻼﻣــــﱵ اﳊﻴــــﺎة ﻣــﻦ ﻧﺎﺣﻴــﺔ أﺧــﺮى ، ﺣﻴــﺚ ﻻ ﳝﻜــﻦ ﻷي ﻣﺼــﺪر ﻃﺒﻴﻌـــﻲ ﻣﻌـــﺮوف أن ﻳﻮﻟـــﺪﻫﺎ ﻓـــﺈن ﺑﻌـــﺾ اﻟﺒﺼـﻤﺎت اﻟﺘﻘﻨﻴـﺔ اﻟـﱵ ﳝﻜـﻦ اﻛﺘﺸــﺎﻓﻬﺎ ﺣـﱴ ﻋﲆ ﻣﺴﺎﻓﺎت ﺑﻌﻴﺪة ﻣﺜﻞ اﻹﺷﺎرات اﻟﺮادﻳﻮ ﻳـﺔ ﺿﻴﻘﺔ اﻟﻨﻄﺎق ﺟﺪًا ، ﻫﻲ ﺑﺎﻟﺘﺄﻛﻴﺪ أﻗﻞ ﻏﻤﻮﺿًـﺎ ﺣﻴـﺚ ﻻ ﳝﻜـﻦ ﻷي ﻣﺼــﺪر ﻃﺒﻴﻌـﻲ ﻣﻌـﺮوف أن ﻳﻮﻟــﺪﻫﺎ . ﻫــﺬه اﳌﺮﺣﻠــﺔ ﻣــﻦ اﻟﺴـــﻬﻞ ﻓﻬــﻢ ﺳ ﺐ ﺗﻔﻀﻴﻞ ﻋﻠﻤﺎء اﻷﺣﻴـﺎء اﻟﻔﻠﻜﻴـﺔ اﻟﺒﺤـﺚ ﻋﻦ إﺷﺎرة ﺷـﺎذة ﺣﻘـﻞ ﻧﺠـﻢ ﻛﺒـﲑ ﻳﺤﺘـﻮي ﻋــﲆ اﻷرﺟــﺢ ﻋــﲆ آﻻف أو ﻣﻼﻳــﲔ اﻟﻜﻮاﻛــﺐ ﺑﺪﻻً ﻣﻦ اﻟﻜﻔﺎح ﻟﻌﺰل ﻃﻴﻒ ﻛ ﻮﻛﺐ واﺣﺪ ﺑﺤﺜًﺎ ﻋﻦ اﳉﺰﻳﺌﺎت اﻟﱵ ﻻ ﳝﻜﻦ رﺑﻄﻬ ﺎ اﻟﻴﻮم ﺑﺎﻟﻴﻘﲔ ﺑﻮﺟــــﻮد اﳊﻴــــﺎة . ﻫــــﺬا اﻟﺴــــﻴﺎق اﻟﻔﻠــــﲄ اﻟﺒﻴﻮﻟــﻮﴂﺳــﺘﻜﻮن اﳌﺘﻐــﲑات اﻟــﱵ اﻗﱰﺣﻬــﺎ أر ﻳـــﺖ وزﻣــﻼؤه ﻣﻔﻴــﺪة ﺗﻄـــﻮﻳﺮ اﳌﻨﺎﻗﺸــﺔ ﺣﻮل اﻵﺛﺎر اﳌﱰﺗﺒﺔ ﻋﲆ ﺑﻌﺾ ﺧﺼﺎﺋﺺ اﳊﻴﺎة اﻟﺘﻜﻨﻮﻟﻮﺟﻴﺔ اﻟﱵ ﺗﺨﺘﻠﻒ اﺧﺘﻼﻓًﺎ ﺟﻮﻫﺮﻳًﺎ ﻋﻦ ﺧ ﺼﺎﺋﺺ اﳊﻴﺎة ﻏﲑ اﻟﺘﻜﻨﻮﻟﻮﺟﻴﺔ . ــــــــــﺎت اﻟﻔﻀـــــــــــﺎﺋ ﺔ ﻤﻜــــــــــﻦ اﻛﺘﺸــــــــــﺎف اﻟﻤﺮﻛ ـــــﺔ ﻣـــــﻦ ﻣﺌـــــﺎت إﻟـــــﻰ آﻻف اﻟﺴـــــﻨ اﻟﺒ ﻨ ﻤ اﻟﻀــــﻮﺋ ﺔ ﻣـــــﻦ ﺧــــﻼل أﺷـــــ ﺎل ﻣﺨﺘﻠﻔــــﺔ ﻣــــﻦ اﻹﺷـــــــــﻌﺎع . أﻇﻬـــــــــﺮاﻟ ﻮ ﻜـــــــــﺐ أوﻣﻮاﻣـــــــــﻮا ) اﻟﻤﻮﺿـﺢﻫﻨـﺎ ( اﺳـﺘﻘ ﺎل أﻧــﮫ ﻤﻜﻨﻨـﺎ ﺣــ ز ــــﺎراتﻣــــﻦ أﺟﺴــــﺎم ـــــﺔ ﻣــــﻦ أﻧﻈﻤــــﺔ ﻮﻛﺒ أﺧﺮى . [ESA/Hubble, NASA, ESO, M. Kornmesser] ـــــــــــﺔ اﻟﻌﻤﻼﻗـــــــــــﺔ ﻣﺜـــــــــــﻞ ﻛـــــــــــﺮة ﺳــــــــــﺘ ﻮن اﻟ ﻨ دا ﺴـــــﻮن ) اﻟﻤﺼـــــﻮرةﻫﻨـــــﺎ ( ﻗـــــﺎدرة ﻋﻠــــــﻰ ﺗﻮﻟ ﺪ ﺼﻤﺎت ﺗﻘﻨ ﺔ ﻣﺮ ﺔ ﻋﻠﻰﻣﺴﺎﻓﺎت ﻛﺒــــــ ة ﻓــــــﻲ اﻟﻤﺠــــــﺮة ، ﻣﻤــــــﺎ ﻜﺸــــــﻒﻋـــــــﻦ ـــﺔ ﻓﻀـــﺎﺋ ﺔ ﺣــــ وﺟــــﻮد ﺣﻀـــﺎرة ﺗﻜﻨﻮﻟﻮﺟ ﻓﻲﻏ ﺎب اﻻﺗﺼﺎﻻت اﻟﻼﺳﻠﻜ ﺔ ﻣﺠﻠﺔ Astronomy ﺎﻟﻌﺮ ﺔ ٤٠ [Capnhack.com]