Free Astronomy Magazine July-August 2022 ARABIC VERSION

jets emanating from the central nu- cleus. A synchrotron jet exists in 3C273 as well, seen in the lower right of the images. An essential characteristic of synchrotron emis- sion is its brightness changes with frequency, but the faint radio emis- sion discovered by the team had con- stant brightness irrespective of the radio frequency. After considering alternative mechanisms, the team found that this faint and extended radio emission came from hydrogen gas in the galaxy energized directly by the 3C273 nucleus. This is the first time that radio waves from such a mechanism are found to extend for tens of thousands of light-years in the host galaxy of a quasar. As- tronomers had overlooked this phe- nomenon for decades in this iconic cosmic lighthouse. So why is this dis- covery so important? It has been a big mystery in galactic astronomy whether the energy from a quasar nucleus can be strong enough to de- prive the galaxy’s ability to form stars. The faint radio emission may help to solve it. Hydrogen gas is an essential ingredient in creating stars, but if such an intense light shines on it that the gas is disassembled (ion- ized), no stars can be born. To study whether this process is happening around quasars, astronomers have used optical light emitted by ionized gas. The problem working with op- tical light is that cosmic dust absorbs the light along the way to the tele- scope, so it is difficult to know how much light the gas gives off. More- over, the mechanism responsible for giving off optical light is complex, forcing astronomers to make a lot of assumptions. The radio waves dis- covered in this study come from the same gas due to simple processes and are not absorbed by dust. Using radio waves makes measuring io much easier. In this study, the as       Q ated by light scattered by the telescope. At the lower right is a high-energy jet released by the gas around the central uasar 3C273 observed by the Hubble Space Telescope (left). The exceeding brightness results in radial leaks of light cre- black hole. Radio image of 3C273 (right) observed by ALMA, showing the faint and extended radio emission (in blue-white color) around the nucleus. The bright central source has been subtracted from the image. The same jet as the image on the left can be seen in orange. [Komugi et al., NASA/ESA Hubble Space Telescope] ﻟﻠﻨﻔﺎﺛﺎت اﳌﻨﺒﻌﺜﺔ ﻣﻦ اﻟﻨﻮاة اﳌﺮﻛﺰﻳـﺔ . ﻳﻮﺟـﺪ ﻧﻔــــﺎث اﻟﺴــــﻨﻜﺮوﺗﺮون أﻳﻀًــــﺎ اﻟﻜــــﻮازار 3C273) ( وﻳُــــﺮى أﺳــــﻔﻞ ﳝــــﲔ اﻟﺼــــﻮر اﻟﺴـﻤﺔ اﻷﺳﺎﺳــﻴﺔ ﻻﻧﺒﻌــﺎث اﻟﺴــﻨﻜﺮوﺗﺮون و ﻫﻲ ﺗﻐﲑ ﺳﻄﻮﻋﻬﺎ ﻣﻊ اﻟﱰدد ﻟﻜـﻦ اﻧﺒﻌـﺎث اﻟﺮادﻳﻮ اﳋﺎﻓـﺖ اﻟـﺬي اﻛﺘﺸـﻔﻪ اﻟﻔﺮﻳـﻖ ﻛـﺎن ﻟــﻪ ﺳــﻄﻮع ﺛﺎﺑــﺖ ﺑﻐــﺾ اﻟﻨﻈــﺮ ﻋــﻦ ﺗــﺮدد اﻟﺮادﻳــﻮ ، ﺑﻌــﺪ اﻟﺘﻔﻜــﲑ اﻵﻟﻴــﺎت اﻟﺒﺪﻳﻠــﺔ وﺟــﺪ اﻟﻔﺮﻳـــﻖ أن ﻫـــﺬا اﻻﻧﺒﻌـــﺎث اﻟﺮادﻳـــﻮي اﳋﺎﻓﺖ واﳌﻤﺘﺪ ﺟﺎء ﻣـﻦ ﻏـﺎز اﻟﻬﻴـﺪروﺟﲔ اﳌﺠﺮة اﻟﺬي ﻳﺘﻢ ﺗﻨﺸ ﻴﻄﻪ ﻣﺒﺎﴍة ﺑﻮاﺳـﻄﺔ ﻧــﻮاة اﻟﻜــﻮازار ) (3C273 وﻫــﺬه ﻫــﻲ اﳌــﺮة اﻷوﱃ اﻟـﱵ ﻳـﺘﻢ ﻓﻴﻬـﺎ اﻛﺘﺸـﺎف أن اﳌﻮﺟـﺎت اﻟﺮادﻳﻮﻳـﺔ ﲟ ﺜـﻞ ﻫـﺬه اﻵﻟﻴـﺔ وﲤﺘـﺪ ﻟﻌﴩــات اﻵﻻف ﻣـــﻦ اﻟﺴـــ ﲔ اﻟﻀـــﻮﺋﻴﺔ اﳌﺠـــﺮة اﳌﻀﻴﻔﺔ ﻟﻠﻜﻮازار . ﺗﺠﺎﻫﻞ ﻋﻠﻤﺎء اﻟﻔﻠﻚ ﻫﺬه اﻟﻈــﺎﻫﺮة ﻟﻌﻘــﻮد ﻫــﺬه اﳌﻨــﺎرة اﻟﻜﻮﻧﻴــﺔ اﻟﺸﻬﲑة ﻓﻠ ، ﻤﺎذا ﻫﺬا اﻟﻌﺮض ﻣﻬﻢ ﺟﺪا؟ ﻟﻘﺪ ﻛﺎن ﻟﻐﺰًا ﻛﺒﲑًا ﻋﻠﻢ اﻟﻔﻠﻚ اﳌﺠﺮي ، ف ذا ﻣﺎ ﻟــــﻮ ﻛﺎﻧــــﺖ اﻟﻄﺎﻗــــﺔ ﻣــــﻦ ﻧــــﻮاة اﻟﻜــــﻮازار ــــــــــــــــــــــ ﳝﻜﻦ أن ﺗﻜﻮن ﻗﻮﻳﺔ ﲟﺎ ﻳﻜﻔﻲ ﳊﺮﻣﺎن اﳌﺠـﺮة ﻣﻦ اﻟﻘﺪرة ﻋﲆ ﺗﻜـﻮﻳﻦ اﻟﻨﺠـﻮم ، ﻗـﺪ ﻳﺴـﺎﻋﺪ اﻧﺒﻌـﺎث اﻟﺮادﻳـﻮ اﳋﺎﻓـﺖ ﺣﻠﻬـﺎ . ﻳﻌﺘـﱪ ﻏـﺎز اﻟﻬﻴـــﺪروﺟﲔ ﻣ ﻜﻮﻧًـــﺎ أﺳﺎﺳـــﻴًﺎ ﺗﻜـــﻮﻳﻦ اﻟﻨﺠـﻮم وﻟﻜــﻦ إذا ﺳـﻄﻊ ﻋﻠﻴـﻪ ﺿـﻮء ﺷـﺪﻳﺪ ﺑﺤﻴ ﺚ ﰎ ﺗﻔﻜﻴﻚ اﻟﻐﺎز ) ( ﻣﺘﺄﻳﻨًﺎ ، ﻓﻼ ﳝﻜﻦ أن ﺗﻮﻟـﺪ أي ﻧﺠـﻮم . ﻟﺪراﺳـﺔ ﻣــﺎ إذا ﻛﺎﻧـﺖ ﻫـﺬه اﻟﻌﻤﻠﻴـﺔ ﺗﺤـﺪث ﺣـﻮل اﻟﻜـﻮازارات، اﺳـﺘﺨﺪم ﻋﻠﻤﺎء اﻟﻔﻠﻚ اﻟﻀﻮء اﳌﺮﰄ اﳌﻨﺒﻌﺚ ﻣﻦ اﻟﻐـﺎز اﳌﺘﺄﻳﻦ ، ﻣﺸﻜﻠﺔ اﻟﻌﻤﻞ ﻣﻊ اﻟﻀﻮء اﳌﺮﰄ ﻫﻲ أن اﻟﻐﺒـﺎر اﻟﻜـﻮﱐ ﻳﻘـﻮم ﺑﺎﻣﺘﺼـﺎص اﻟﻀـﻮء ﻋﲆ ﻃﻮل اﻟﻄﺮﻳﻖ إﱃ اﻟﺘﻠﺴ ﻜﻮب ﻟﺬﻟﻚ ﻣـﻦ اﻟﺼﻌﺐ ﻋﲆ اﻟﺒﺎﺣﺜﲔ ﻣﻌﺮ ﻓﺔ ﻣﻘﺪار اﻟﻀـﻮء اﻟـﺬي ﻳﺼـﺪره اﻟﻐـﺎز ، ﻋـﻼوة ﻋـﲆ ذﻟـﻚ ، ﻓـﺈن اﻵﻟﻴــﺔ اﳌﺴــﺌﻮﻟﺔ ﻋــﻦ إﻋﻄــﺎء اﻟﻀــﻮء اﳌــﺮﰄ ﻣﻌﻘﺪة ﳑﺎ ﻳﺠﱪ اﻟﻔﻠﻜﻴﲔ ﻋـﲆ وﺿـﻊ اﻟﻜﺜـﲑ ﻣﻦ اﻻﻓﱰاﺿﺎت ، إﺿﺎﻓﺔ أن ﻣﻮﺟﺎت اﻟﺮادﻳـﻮ اﻟﱵ ﲤﺖ ﺗﻐﻄﻴﺘﻬﺎ ﻫﺬه اﻟﺪراﺳﺔ ﺗﺄﰐ ﻣـﻦ ﻧﻔﺲ اﻟﻐﺎز ﻟﻚوذ ﺑﺴ ﺐ ﻋﻤﻠﻴـﺎت ﻓﲒﻳﺎﺋﻴـﺔ ﺑﺴـﻴﻄﺔ وﻻ ﺟـﺪاً ﻳﻘـﻮم اﻟﻐﺒـﺎر ﺑﺎﻣﺘﺼﺎﺻـﻬﺎ ــــــــــــــــــــــــــــــــــــــــ ﻟﻘـــﺪ ﰎ اﺳـــﺘﺨﺪام ﻣﻮﺟـــﺎت اﻟﺮادﻳـــﻮ ﻌـــﻞ ﳉ ﻗﻴﺎس اﻟﻐﺎز اﳌﺆﻳﻦ اﻟﻨـﺎﺗﺞ ﻋـﻦ ﻧـﻮاة اﻟﻜـﻮازار (3C273) أﺳــﻬﻞ ﺑﻜﺜـــﲑ . ﻫــﺬه اﻟﺪراﺳــﺔ وﺟﺪ ﻋﻠﻤﺎء اﻟﻔﻠﻚ أن ﻣﺎ ﻻ ﻳﻘـﻞ ﻋـﻦ ٧ ٪ ﻣـﻦ اﻟﻀــﻮ ء ﻣــﻦ اﻟﻜــﻮازار ) (3C273 ﻗــﺪ اﻣﺘﺼــﻪ اﻟﻐـﺎز اﳌﺠـﺮة اﳌﻀــﻴﻔﺔ ﳑــﺎ أدى إﱃ إﻧﺘــﺎج ﻏـﺎز ﻣـﺆﻳﻦ ﺗﺒﻠـﻎ ﻛﺘﻠﺘـﻪ ١٠ - ١٠٠ ﻣﻠﻴـﺎر ﺿـﻌﻒ ﻛﺘﻠــﺔ اﻟﺸــﻤﺲ وﻣــﻊ ذﻟــﻚ ﻛــﺎن اﻟﻜــﻮازار 3C273) ( ﻳﺤﺘﻮي ﻋﲆ ﻛﻤﻴﺔ ﻛﺒﲑة ﻣﻦ اﻟﻐﺎز ﻗﺒـﻞ ﺗﻜـﻮﻳﻦ اﻟﻨﺠـﻮم ﻟـﺬﻟﻚ ﻛﻜـﻞ ﻻ ﻳﺒـﺪو أن ﺗﻜـــﻮﻳﻦ اﻟﻨﺠـــﻮم ﻗـــﺪ ﰎ ﻗﻤﻌـــﻪ ﺑﻘـــﻮة ﻣـــﻦ ﺑﻮاﺳــ ﻄﺔ اﻟﻨــﻮاة ، ﻳﻘــﻮل ﺷــ ﻨﻴﺎ ﻛﻮﻣــﻮﴂ اﻷﺳــﺘﺎذ اﳌﺴــﺎﻋﺪ ﺟﺎﻣﻌــﺔ ﻛﻮﺟــﺎﻛﻮﻳﻦ و اﳌﺆﻟﻒ اﻟﺮﺋﻴﴘـ ﻟﻠﺪراﺳـﺔ اﳌﻨﺸـﻮرة ﳎﻠـﺔ اﻟﻔﲒﻳــﺎء اﻟﻔﻠﻜﻴــﺔ " : ﻳــﻮﻓﺮ ﻫــﺬا اﻻﻛﺘﺸــﺎف وﺳــﻴﻠﺔ ﺟﺪﻳــﺪة ﻟﺪراﺳــﺔ اﳌﺸــﻜﻼت اﻟــﱵ ﰎ ﺗﻨﺎوﻟﻬــﺎ ﺳـﺎﺑﻘًﺎ ﺑﺎﺳــﺘﺨﺪام اﻟﺮﺻـﺪ ﺑﺎﻟﻀــﻮء اﳌــﺮﰄ " ." ﻣــﻦ ﺧــﻼل ﺗﻄﺒﻴــﻖ ﻧﻔــﺲ اﻟﺘﻘﻨﻴــﺔ ﻋــﲆ اﻟﻜــﻮازارات اﻷﺧــﺮى ﻧﺘﻮﻗـــﻊ أن ﻧﻔﻬـــﻢ ﻛﻴﻒ ﺗﺘﻄﻮر اﳌﺠﺮة وذﻟﻚ ﻣﻦ ﺧﻼل ﺗﻔﺎﻋﻠﻬـﺎ اﻟﺪاﰂ ﻣﻊ اﻟﻨﻮاة اﳌﺮﻛﺰﻳﺔ ". ـــﻮازار اﻟ 3C273) ( اﻟﻤﺮﺻــــﻮد ﺑﻮاﺳـــﻄﺔ ﺗﻠﺴـــ ﻮبﻫﺎﺑـــﻞ اﻟﻔﻀــــﺎﺋﻲ (. ﺴـــﺎر ) ﻨــــﺘﺞ ﻋـــﻦ اﻟﺴــــﻄﻮع اﻟﺰاﺋـــﺪ ﺗﺴــــﺮ ﺷـــﻌﺎﻋﻲ ﻟﻠﻀــــﻮء ﻧﺎﺗﺠـــﺔ ﻋــــﻦ اﻟﻀـــﻮء اﻟﻤﻨﺘﺸــــﺮ ﺑﻮاﺳــﻄﺔ اﻟﺘﻠﺴــ ﻮب . ﻓــﻲأﺳــﻔﻞ اﻟ ﻤــ ـﺔ اﻟﻄﺎﻗــﺔ ﻄﻠﻘﻬـﺎ اﻟﻐــﺎزﺣــﻮل اﻟﺜﻘــﺐ اﻷﺳـﻮد اﻟﻤﺮﻛــﺰي ﺗﻮﺟــﺪ ﻧﻔﺎﺛــﺔ ﻋﺎﻟ . ــﻮازار ـﺔ ﻟﻠ ﺻــﻮرة رادﻳﻮ 3C273 ) ( ﻤــ رﺻـﺪﻫﺎ ﻣﺮﺻـﺪ ) ALMA ( ، ﺗﻈﻬـﺮاﻧ ﻌـﺎث اﻟﺮادﻳـﻮ ا ﺎﻓـﺖواﻟﻤﻤﺘــﺪ ـﺎ) ﻟﻠﻮن اﻷزرقواﻷﺑـ ﺾ ( ﺣــﻮل اﻟﻨـﻮاة ، ﺗـﻢﻃــﺮح اﻟﻤﺼـﺪراﻟﻤﺮﻛـﺰي اﻟﺴــﺎﻃﻊﻣـﻦ اﻟﺼــﻮرة ﻤﻜﻦ رؤ ﺔ ﻧﻔﺲ اﻟﻨﻔﺎﺛﺔ ﻣﺜﻞ اﻟﺼﻮرة اﻟﻤﻮﺟﻮدة ﻋﻠﻰاﻟ ﺴﺎر ﺎﻟﻠﻮن اﻟ ﻘﺎﻟﻲ . [Komugi et al., NASA/ESA Hubble Space Telescope] ﻣﺠﻠﺔ Astronomy ﺎﻟﻌﺮ ﺔ ﻳﻮﻟﻴﻮ – أﻏﺴﻄﺲ 2022 ٢٤