Free Astronomy Magazine March-April 2023 ARABIC VERSION

decades with data collected by the citizen science project “Globe at Night” (www.globeatnight.org), started in 2006 by the National Optical-Infrared Astron- omy Research Laboratory (NOIRLab) of the U.S. National Science Foun- dation. This project has so far produced over 200,000 skyglow esti- mates in nearly 20,000 different locations on all continents. The project participants observe the starry sky (without the Moon) from their own location, compare what they see with eight refer- ence celestial charts of various constellations, and via an online form com- municate which of the charts has the most cor- respondence with their observed sky. Taken as a whole, the network of “citizen scientists” func- tions as a global sensor that allows evaluation of the sky- glow exactly at the wavelengths of visible light, something that elec- tronic sensors, especially those in or- bit, cannot do with the same effi- ciency. The only satellite that be- tween 1992 and 2013 collected in- formation also useful for evaluating the light emission from the ground (as part of the Defense Meteorolog- ical Satellite Program) was not in- tended for research purposes and the data it provided were not easy to interpret for scientific purposes. Furthermore, in urban centers, the data pr ovided was often “sat ura- ﻣﺠﻠﺔ Astronomy ﺎﻟﻌﺮ ﺔ ٦ ﻣﺎرس أﺑﺮﻳﻞ 2023 ﺗُﻈﻬـﺮﺻــﻮررواد اﻟﻔﻀــﺎء ﻷﺟـﺰاء ﻣــﻦ ﺎﻟــ ـ ( ﻛﻨــﺪا ) ﺠﺎري ـﺔ ﺗﻐــ اﻹﺿــﺎءة ﻣــﻦ أﻣﺜﻠــﺔ ﻋﻠــﻰﻛ ﻔ ٢٠١٠ إﻟــﻰ ٢٠٢١ : ـــﺪ ﻣـــﻦ ﻣﺼـــﺎﺑﻴﺢ اﻟﺸـــﻮارع ﻣـــﻦ اﻟﺼـــﻮدﻳﻮم ـــﺪة وﺗـــﻢ ﺗﺤﻮﻳــﻞ اﻟﻌﺪ ـــﺐ إﺿـــﺎءة ﺟﺪ ﺗـــﻢ ﺗﺮﻛ اﻟ ﻘـــﺎﻟﻲﻋـــﺎﻟﻲ اﻟﻀــــﻐﻂ إﻟـــﻰ إل إيد اﻷﺑــــ ﺾ . ـــﺘﻢ اﻟﺘﻘـــﺎط اﻟﺼــــﻮر ﻓـــﻲ ﻧﻔــــﺲ ﺑ ﻨﻤـــﺎ ﻟــــﻢ اﻹﻋـﺪادات ﻓــﺈن اﻻﻧﺨﻔـﺎض اﻟﻤﻠﺤــﻮظ ﻓــﻲ اﻟﺴـﻄﻮع ﻓـﻲﺻـﻮرة ٢٠٢١ ﻟــﻢ ﻜــﻦ ﻛﺒـ اً ــﺎس ﻋﻨــﺪ اﻟﻘ ﻣﻦ اﻟﺴﻄﺢ . ﻟﻢ ﻘﻠﻞ اﻻﻧﺘﻘﺎل إﻟﻰﻣﺼﺎ ﺑﻴﺢ إل إيد ﻣﻦ ﺗﻮﻫﺞ اﻟﺴﻤﺎء . اﻟﻌﻘﻮد ا ﺎﺿﻴﺔ ﺑﺎﺳﺘﺨﺪام اﻟﺒﻴﺎﻧﺎت اﻟﺘـﻲ ﺗـﻢ ﺟﻤﻌﻬﺎ ﺑﻮاﺳﻄﺔ ﻣﴩوع ﻳﺴﻤﻰ " ﻏﻠﻮﺑﺎل ات ) " ﻧﺎﻳﺖ www.globeatnight.org ( واﻟﺬي ﺑﺪأ ﻋﻤﻠـﻪ ﰲ اﻟﻌـﺎم ٢٠٠٦ ﺑﻮاﺳـﻄﺔ ا ﺨﺘﱪ اﻟﻮﻃﻨﻲ ﻟﺒﺤـﻮث اﻟﻔﻠـﻚ ﺑﺎﻷﺷــﻌﺔ ﺗﺤ ــﺖ اﻟ ـــﺤﻤﺮاء اﻟﻀــﻮﺋﻴﺔ ) ﻧــﻮﻳﺮﻻب ( اﻟﺘــﺎﺑﻊ ﺆﺳﺴــﺔ اﻟﻌﻠ ــﻮم اﻟﻮﻃﻨﻴ ــﺔ اﻷﻣﺮﻳﻜﻴﺔ ﻟﻘﺪ . اﺳﺘﻄﺎع ا ﴩوع ﺣﺘــﻰ اﻵن إﻧﺘــﺎج أﻛﺜــﺮ ﻣــﻦ ٢٠٠,٠٠٠ ﺗﻘــــﺪﻳﺮ ﻟﻠــــﻮﻫﺞ اﻟﺴ ـﻤﺎوي ﰲ ﻣــﺎ ﻳﻘــﺮب ﻣــﻦ ٢٠,٠٠٠ ﻣﻮﻗﻊ ﻣﺨﺘﻠﻒ ﰲ ﺟﻤﻴﻊ اﻟﻘﺎرات . ﻟﻘﺪ رﺻﺪ ا ﺸﺎرﻛﻮن ﰲ ﻫﺬا ا ﴩوع اﻟﺴـﻤﺎء ا ﺮﺻـﻌﺔ ﺑـﺎﻟﻨﺠﻮم ) ﺑـﺪون اﻟﻘﻤـﺮ ﻣـﻦ ( ﻣﻮﻗﻌﻬﻢ اﻟﺨـﺎص ا وﻗـﺎرﻧﻮ ﻣـﺎ ﻳﺮوﻧــﻪ ﺑﺜﻤﺎﻧﻴــﺔ ﻣﺨﻄﻄــﺎت ﺳﻤﺎوﻳﺔ ﻣﺮﺟﻌﻴـﺔ ﻣـﻦ اﻷﺑـﺮاج ا ﺔ ﺨﺘﻠﻔ وﻣﻦ ﺧﻼل ﻧﻤﻮذج ﻋـﱪ اﻹﻧﱰﻧﺖ ﻳﻮﺻﻞ أي ﻣﻦ اﻟﺮﺳـﻮم اﻟﺒﻴﺎﻧﻴ ـﺔ ﻟ ـﻪ أﻛــﱪ ﻗ ـﺪر ﻣــﻦ ا ﺮاﺳﻼت ﻣﻊ اﻟﺴﻤﺎء ا ﺮﺻﻮدة . اﻟﺒﻴﺎﻧﺎت ﻣﻊ اﻟﺴﻤﺎء ا ﺮﺻﻮدة . ﺑﺸﻜﻞ ﻋـﺎم ﺗﻌﻤــﻞ ﺷـــﺒﻜﺔ " اﻟﻌﻠﻤــﺎء ا ﺘﻄــﻮﻋ " ﻛﻤﺴﺘﺸﻌﺮ ﻋـﺎ ﻲ ﻳﺴـﻤﺢ ﺑﺘﻘﻴـﻴﻢ اﻟـﻮﻫﺞ اﻟﺴﻤﺎ وي اﻟﺼـﻨﺎﻋﻲ ﺑﺎﻟﻀـﺒﻂ ﻋﻨـﺪ اﻷﻃـﻮال ا ﻮﺟﻴﺔ ﻟﻠﻀﻮء ا ﺮﺋﻲ وﻫـﻮ أﻣـﺮ ﻻ ﺗﺴـﺘﻄﻴﻊ ا ﺴﺘﺸـﻌﺮات اﻹﻟﻜﱰوﻧﻴ ـﺔ ﺧﺎﺻـﺔ ﰲ ا ـﺪار اﻟﻘﻴﺎم ﺑﻪ ﺑﻨﻔﺲ اﻟﻜﻔـﺎءة ، اﻟﻘﻤـﺮ اﻟﺼـﻨﺎﻋﻲ اﻟﻮﺣﻴﺪ اﻟﺬي ﺟﻤﻊ ا ﻌﻠﻮﻣﺎت ﺑ ﻋﺎﻣﻲ ١٩٩٢ و ٢٠١٣ ﻣﻔﻴﺪ أﻳﻀًﺎ ﰲ ﺗﻘﻴﻴﻢ اﻧﺒﻌـﺎث اﻟﻀـﻮء ﻣ ـﻦ اﻷرض ) ﻛﺠ ـﺰء ﻣــﻦ ﺑﺮﻧ ـﺎﻣﺞ اﻷﻗﻤــﺎ ر اﻟﺼﻨﺎﻋﻴﺔ اﻟﺪﻓﺎﻋﻴﺔ ﻟﻸرﺻﺎد اﻟﺠﻮﻳﺔ ﻟﻢ واﻟﺬي ( ﻳﻜﻦ ﻣﺨﺼﺼًﺎ ﻟﻠﺒﺤﻮث وﻟﻢ ﻳﻜﻦ ﻣـﻦ اﻟﺴـﻬﻞ ــــﺚ اﻟﺘﻠـــﻮث اﻟﻀــــﻮﺋﻲ ﺗـــﻢ ﺗﺼــــﻨ ﻒﻫﻮﻧــــﻎ ﻮﻧــــﻎ ﻋﻠـــﻰ أﻧﻬــــﺎ أﺳــــﻮأ ﻣﺪ ﻨــــﺔ ﻓـــﻲ اﻟﻌــــﺎﻟﻢ ﻣــــﻦ ﺣ . ــــﺪو أن اﻟﻤﻨــــﺎﻃﻖ اﻟﺘﺠﺎر ــــﺔ ﻳ ــﻮزواي ــﻮك وﺗﺴــ ﻢﺷــﺎ ﺗﺴــﻮيوﺧﻠــﻴـﺞ واﻟﺴــﻜﻨ ﺔ ﻓــﻲﻣﻮﻧــﻎ ﻫــﻲ أﻛــ اﻟﻤﻨــﺎﻃﻖ ﺗﻠﻮﺛًـﺎ . ﻋــﺪد ﻻ ﺣﺼــﺮ ﻟــﮫ ﻣــﻦ ﻣﺼــﺎدر اﻟﻀﻮء ، ﻛﺜ ﻣﻨﻬﺎ ﺴﺘﺨﺪم ﺗﻘﻨ ﺔ إل إيد ﺗ، ﺠﻌﻞﺳﻤﺎء ﻫﻮﻧ ﻎ ﻎﻮﻧ أﻛ إﺷﺮاﻗًﺎ ﻣﻦﺳﻤﺎء اﻟﻤﺪن اﻟﻜ ى اﻷﺧﺮى .