Free Astronomy Magazine September-October 2024

ure far-off cosmic distances andhelp scientists to calculate the uni- verse’s expansion rate. The team identifiedatleastoneTypeIasuper- nova at a redshift of 2.9. The light from this explosion began traveling to us 11.5 billion years ago whenthe universe was just 2.3 billion years old. The previous distance record for a spectroscopically con- firmed Type Ia supernova was a red- shiftof1.95,whentheuniversewas 3.4billionyearsold. Scientists are eager to analyze Type Ia supernovae at high redshifts toseeiftheyallhavethesameintrinsic brightness, regardless of distance. This is critically important, because if their brightness varies with red- shift, they would not be reliable markers for measuring the expan- sion rate of the universe. Pierel analyzed this Type Ia super- novafoundatredshift2.9todeter- mine if its intrinsic brightness was differentthanexpected.Whilethis isjustthefirstsuchobject,there- sultsindicatenoevidencethatType Iabrightnesschangeswithredshift. More data is needed, but for now, Type Ia supernova-based theories abouttheuniverse’sexpansionrate anditsultimatefateremainintact. Pierelalsopresentedhisfindingsat the 244 th meeting of the American Astronomical Society. The early universe was a very differ- ent place with extreme environ- ments.Scientistsexpecttoseean- cient supernovae that come from stars that contain far fewer heavy chemical elements than stars like our Sun. Comparing these super- novaewiththoseinthelocaluni- verse will help astrophysicists un- derstand star formation and super- nova explosion mechanisms at these early times. “We’re essentially opening a new windowonthetransientuniverse,” said STScI Fellow Matthew Siebert, who is leading the spectroscopic analysis of the JADES supernovae. “Historically,wheneverwe’vedone that,we’vefoundextremelyexcit- ing things — things that we didn’t expect.” “Because Webb is so sensitive, it’s finding supernovae and other transients almost everywhere it’s pointed,” said JADES team member Eiichi Egami, a research professor at the University of Arizona in Tucson. “This is the first significant step to- ward more extensive surveys of su- pernovaewithWebb.”     ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 30 ﺗﻌــــﺮض ﻫـــــﺬﻩ اﻟﺼـــــﻮر ﺛﻼﺛــــــﺔ ﻣـــــــﻦ ﺣـــــــﻮاﻟﻲ 80 ﺣــــــــﺪﺛﺎً أو ﻋــــــــﺎﺑﺮاً أﺟﺮاﻣــــــــﺎً ذاتﺳـــﻄﻮع ﻣﺘﻐـــ ﺗـــﻢ ـــــــﺪﻫﺎ ﻓــــــــﻲ ﺑ ﺎﻧــــــــﺎت ﺗﺤﺪ ﺟــــــﺎد ﺲ وﻫـــــــﻮ ﺑﺮـــــــﺎﻣﺞ اﻟﻤﺴــــﺢ اﻟﻌﻤﻴــــﻖﺧــــﺎرج اﻟﻤﺠـــــــــــــــــﺮة اﻟﻤﺘﻘــــــــــــــــــﺪم ( ــــﺐ اﻟﺘــــﺎﺑﻊ ﻟﺘﻠﺴــــ ﻮب و . ﻣﻌﻈــــــــــــــــــــــﻢ اﻷﺣــــــــــــــــــــــﺪاث اﻟﻌــــــــــﺎﺑﺮ ة ﻫــــــــــﻲ ﻧﺘﻴﺠــــــــــﺔ ﻻﻧﻔﺠـــــــــــــــــﺎراﻟﻨﺠــــــــــــــــــﻮم أو اﻟﻤﺴـــﺘﻌﺮات اﻟﻌﻈﻤـــﻰ وﻣـــــــــــﻦ ﺧـــــــــــﻼل ﻣﻘﺎر ـــــــــــﺔ اﻟﺼــــﻮر اﻟﻤﻠﺘﻘﻄــــﺔ ﻓــــﻲ ﻋﺎﻣﻲ 2022 و 2023 ﺴـــــــــــــــﺘﻄﻴﻊ اﻟﻔﻠﻜﻴـــــــــــــــﻮن ـــــــــــــــــــــــــــــــــﺪ ﻣﻮﻗــــــــــــــــــــــــــــــــــﻊ ﺗﺤﺪ اﻟﻤﺴـــﺘﻌﺮات اﻟﻌﻈﻤـــﻰ ﻣــــﻦ وﺟﻬــــﺔ ﻧﻈﺮــــﺎ اﻟــــ ﺗﻤﺜﻞ اﻧﻔﺠﺮ ) ﺣﺪ ﺜﺎً ﻣﺜﻞ اﻷﻣﺜ ﻠـﺔ اﻟﻤﻮﺿـﺤﺔ ﻓـﻲ اﻟﻌﻤـﻮدﻳﻦ اﻷوﻟـ ( أو اﻟﻤﺴـﺘﻌﺮات اﻟﻌﻈﻤـﻰ ـﺎن ﺿـﻮءﻫﺎ ﺘﻼﺷـﻰ اﻧﻔﺠـﺮ ﺎﻟﻔﻌـﻞ و اﻟـ ) اﻟﻌﻤـﻮد اﻟﺜﺎﻟـﺚ ( ﻤﻜـﻦ ﺗﺤﺪ ﺪ ﻋﻤﺮ ﻞ ﻣﺴﺘﻌﺮأﻋﻈﻢ ﻣﻦ ﺧﻼل اﻧﺰ ﺎﺣﮫ ﻧﺤﻮ اﻷ ﻤﺮ ) اﻟﻤﺸﺎرإﻟ ﮫ ﺎﻟﺮﻣﺰ "z(" . ﻧﺸـﺄ ﺿـﻮء اﻟﻤﺴـﺘﻌﺮاﻷﻋﻈـﻢ اﻷ ﻌـﺪ ﻋﻨـﺪ اﻧﺰ ـﺎح أ ﻤـﺮﻗـﺪرﻩ 3.8 ـﺎن ﻋﻨـﺪﻣﺎ ﻋﻤﺮ اﻟ ﻮن 1,7 ﻣﻠ ﺎرﺳﻨﺔ ﻓﻘﻂ و ﺘﻮاﻓﻖ اﻻﻧﺰ ﺎح اﻷ ﻤﺮاﻟ ﺎﻟﻎ 2.854 ﻣﻊ زﻣﻦ ﻌﺪ اﻻﻧﻔﺠﺎراﻷﻋﻈﻢ ﺑـ 2.3 ﻣﻠ ﺎرﺳﻨﺔ . أﻗﺮ ﻣﺜﺎل ﻋﻨﺪ اﻧﺰ ﺎح أ ﻤﺮﻗﺪرﻩ 0.655 ﺗﺮك ﻣﺠﺮﮫ ﻣﻨﺬ ﺣﻮاﻟﻲ ُﻈﻬﺮاﻟﻀﻮء اﻟﺬ 6 ـﺎراتﺳـﻨﺔ ﻣﻠ ـﻮن ﻳﺰ ـﺪ ﻗﻠـ ﻼً ﻋـﻦ ﻧﺼـﻒﻋﻤـﺮﻩ اﻟـ ـﺎن ﻋﻤـﺮاﻟ ﻋﻨـﺪﻣﺎ ـ ]. ﺤﺎﻟﻲ NASA, ESA, CSA, STScI, Christa DeCoursey (University of Arizona), JADES Collaboration [ ﺗﺘﻤﻴﺰ ﻫﺬه اﻟﻨﺠﻮم ا ﺘﻔﺠﺮة ﺑﺴﻄﻮﻋﻬﺎ اﻟﺬي ﻳﻤﻜـﻦ اﻟﺘﻨﺒـﺆ ﺑـﻪ ﻟﺪرﺟـﺔ أﻧﻬـﺎ ﺗُﺴـﺘﺨﺪم ﻟﻘﻴﺎس ا ﺴﺎﻓﺎت اﻟﻜﻮﻧﻴﺔ اﻟﺒﻌﻴﺪة وﻣﺴﺎﻋﺪة اﻟﻌﻠﻤﺎء ﻋﲆ ﺣﺴﺎب ﻣﻌﺪل ﺗﻮﺳﻊ اﻟﻜﻮن . ﺣﺪد اﻟﻔﺮﻳﻖ ﻣﺴﺘﻌﺮ اً أﻋﻈﻢ واﺣﺪ اً ﻋﲆ اﻷﻗﻞ ﻣﻦ اﻟﻨﻮع Ia ﻋﻨﺪ اﻧﺰﻳﺎح أﺣﻤﺮ ﻗـﺪره 2.9. ﺑﺪأ اﻟﻀﻮء اﻟﻨﺎﺗﺞ ﻋﻦ ﻫﺬا اﻻﻧﻔﺠﺎر ﰲ اﻟﺴﻔﺮ إﻟﻴﻨﺎ ﻣﻨﺬ 11.5 ﻣﻠﻴﺎر ﺳﻨﺔ ﻋﻨﺪﻣﺎ ﻛﺎن ﻋﻤـﺮ اﻟﻜﻮن 2.3 ﻣﻠﻴﺎر ﺳﻨﺔ ﻓﻘـﻂ وﻛـﺎن اﻟـﺮﻗﻢ اﻟﻘﻴﺎﳼ اﻟﺴﺎﺑﻖ ﺴﺎﻓﺔ ﻣﺴﺘﻌﺮ أﻋﻈﻢ ﻣـﻦ اﻟﻨﻮع Ia ﺗﻢ ﺗﺄﻛﻴﺪه ﻃﻴﻔﻴ ﺎً ﻫﻮ اﻧﺰﻳﺎح أﺣﻤﺮ ﻗﺪره 1.95 ﻋﻨﺪﻣﺎ ﻛﺎن ﻋﻤـﺮ اﻟﻜـﻮن ﻳﺒﻠـﻎ ﺣﻮاﱄ 3.4 ﻣﻠﻴﺎر ﺳﻨﺔ . ﻳﺘﻮق اﻟﻌﻠﻤﺎء إﱃ ﺗﺤﻠﻴﻞ ا ﺴﺘﻌﺮات اﻟﻌﻈﻤﻰ ﻣـﻦ اﻟﻨـﻮع Ia ﻋﻨـﺪ اﻻﻧﺰﻳﺎﺣـﺎت اﻟﺤﻤـﺮاء اﻟﻌﺎﻟﻴﺔ ﻌﺮﻓﺔ ﻣﺎ إذا ﻛﺎﻧﺖ ﺟ ﻤﻴﻌﻬﺎ ﺗﺘﻤﺘـﻊ ﺑﻨﻔﺲ اﻟﺴﻄﻮع اﻟﺠﻮﻫﺮي ﺑﻐﺾ اﻟﻨﻈﺮ ﻋﻦ ا ﺴﺎﻓﺔ ﻓ ﻬﺬا أﻣـﺮ ﺑـﺎﻟﻎ اﻷﻫﻤﻴـﺔ ﻷﻧـﻪ إذا ـــــ ﻛﺎن ﺳﻄﻮﻋ ﻬﺎ ﻳﺘﻐـ ﻣـﻊ اﻻﻧﺰﻳـﺎح ﻧﺤـﻮ اﻷﺣﻤﺮ ﻓﺈﻧﻬﺎ ﻟﻦ ﺗﻜـﻮن ﻋﻼﻣـﺎت ﻣﻮﺛﻮﻗـﺔ ﻟﻘﻴﺎس ﻣﻌﺪل ﺗﻮﺳﻊ اﻟﻜﻮن . ﻗﺎم ﺑ ﻳﻞ ﺑﺘﺤﻠﻴﻞ ﻫﺬا ا ﺴﺘﻌﺮ اﻷﻋﻈﻢ ﻣـﻦ اﻟﻨﻮع Ia اﻟﺬي وﺟﺪ ﻋﻨﺪ اﻧﺰﻳـﺎح أﺣﻤـﺮ 2.9 ﻟﻴﺤـﺪد ﻣـﺎ إذا ﻛـﺎن ﺳـﻄﻮﻋﻪ اﻟﺠــﻮﻫﺮي ﻣﺨﺘﻠﻔﺎً ﻋﻤﺎ ﻛﺎن ﻣﺘﻮﻗﻌﺎ وﰲ ﺣـ أن ﻫـﺬا ﻫﻮ أول ﺟﺴﻢ ﻣﻦ ﻧﻮﻋﻪ إﻻ أﻧﻪ ﻻ ﻳﻮﺟﺪ دﻟﻴﻞ ﻋﲆ أن ﺳﻄﻮع اﻟﻨﻮع Ia ﻳﺘﻐ ﻣﻊ اﻻﻧﺰﻳﺎح اﻷﺣﻤﺮ . ﻫﻨﺎك ﺣﺎﺟﺔ إﱃ ﻣﺰﻳﺪ ﻣﻦ اﻟﺒﻴﺎﻧـﺎ ت وﻟﻜـﻦ ﰲ اﻟﻮﻗـﺖ اﻟﺤـﺎﱄ ﺗﻈـﻞ اﻟﻨﻈﺮﻳـ ﺎت ا ﺴﺘﻨﺪة إﱃ ا ﺴﺘﻌﺮات ا ﻟﻌﻈﻤﻰ ﻣﻦ اﻟﻨـﻮع Ia ﺣـﻮل ﻣﻌـﺪل ﺗﻮﺳـﻊ اﻟﻜــﻮن وﻣﺼــ ه اﻟﻨﻬﺎﺋﻲ ﺳﻠﻴﻤﺔ ﻛﻤﺎ ﻗﺪم ﺑ ﻳـﻞ ﻧﺘﺎﺋﺠـﻪ ﰲ اﻻﺟﺘﻤ ـﺎع رﻗــﻢ 244 ﻟﻠﺠﻤﻌﻴــﺔ اﻟﻔﻠﻜﻴــﺔ اﻷﻣﺮﻳﻜﻴﺔ . ﻟﻘﺪ ﻛﺎن اﻟﻜـﻮن ا ﺒﻜـﺮ ﻣﻜﺎﻧـﺎ ﻣﺨﺘﻠﻔﺎ ﺗﻤﺎﻣﺎ وﻛﺎﻧﺖ ﺑـﻪ ﺑﻴﺌـﺎت ﻗﺎﺳـﻴﺔ . ﻳﺘﻮﻗﻊ اﻟﻌﻠﻤﺎء رؤﻳـﺔ ا ﺴـﺘﻌﺮات اﻟﻌﻈﻤـﻰ اﻟﻘﺪﻳﻤﺔ اﻟﺘﻲ ﺗﺄﺗﻲ ﻣﻦ اﻟﻨﺠﻮم اﻟﺘﻲ ﺗﺤﺘﻮي اﻟﻘﺪﻳﻤﺔ ﻣـﻦ اﻟﻨﺠـﻮم اﻟﺘـﻲ ﺗﺤﺘـﻮي ﻋـﲆ ﻋﻨﺎﴏﻛﻴﻤﻴﺎﺋ ﻴـﺔ ﺛﻘﻴﻠـﺔ أﻗـﻞ ﺑﻜﺜـ ﻣـﻦ اﻟﻨﺠـﻮم ﻣﺜـﻞ . ﺷﻤﺴــﻨﺎ إن ﻣﻘﺎرﻧـﺔ ﻫـﺬه ا ﺴﺘﻌﺮات اﻟﻌﻈﻤﻰ ﺑﺘﻠﻚ ا ﻮﺟﻮدة ﰲ اﻟﻜﻮن ا ﺤﲇ ﺳﺘﺴﺎﻋﺪ ﻋﻠﻤﺎء اﻟﻔﻴﺰﻳﺎء اﻟﻔﻠﻜﻴﺔ ﻋﲆ ﻓﻬ ـﻢ آﻟﻴــﺎت ﺗﻜــﻮﻳﻦ اﻟﻨﺠ ـﻮم واﻧﻔﺠــﺎر ا ﺴﺘﻌﺮات اﻟﻌﻈﻤﻰ ﰲ ﻫﺬه اﻷوﻗﺎت ا ﺒﻜﺮة . ﻗـﺎل ﻣـﺎﺛﻴﻮ ﺳـﻴﱪت زﻣﻴـﻞ ﻣﻌﻬـﺪ ﻋﻠـﻮم اﻟﺘﻠﺴﻜﻮﺑﺎت اﻟﻔﻀﺎﺋﻴ ﺔ اﻟﺬي ﻳﻘﻮد اﻟﺘﺤﻠﻴـﻞ اﻟﻄﻴﻔﻲ ﻟﻠﻤﺴﺘﻌﺮات اﻟﻌﻈﻤـﻰ ) : ( ﺟـﺎدﻳﺲ " ﻧﺤﻦ ﻧﻔﺘﺢ ﻧﺎﻓـﺬة ﺟﺪﻳـﺪة ﻋـﲆ اﻷﺣـﺪاث اﻟﻜﻮﻧﻴﺔ اﻟﻌﺎﺑﺮ ة ﺣﻴﺚ وﺟﺪﻧﺎ أﺷـﻴﺎء ﻣﺜـ ة ﻟﻠﻐﺎﻳﺔ ﻟﻢ ﻧﺘﻮﻗﻌﻬﺎ "، إﻳﺠـﺎﻣﻲ ﴚ ـ ﻗﺎل إﻳﺘ ﻋﻀـﻮ ﻓﺮﻳـﻖ ﻣﺴـﺢ " : ﺟﺎدﻳﺲ ﺗﻠﺴﻜﻮب وﻳﺐ ﺣﺴـﺎس ﻟﻠﻐﺎﻳـﺔ ﻳﻜﺘﺸﻒ ا ﺴﺘﻌﺮات اﻟﻌﻈﻤﻰ وﻏ ﻫـﺎ ﻣـﻦ اﻟﻈﻮاﻫﺮ اﻟﻌﺎﺑﺮة وﻫﻲ ﺧﻄـﻮة أوﱃ ﻟﻠﻘﻴـﺎم ﺑﻤﺴﺢ ﺷﺎﻣﻞ ﻟﻠﻤﺴﺘﻌﺮات اﻟ . ﻌﻈﻤﻰ - ﺳﺒﺘﻤﺒﺮ ﺃﻛﺘﻮﺑﺮ 2 0 2 4