Free Astronomy Magazine November-December 2023 ARABIC VERSION

W ESO telescopes help unravel pulsar puzzle by ESO Bárbara Ferreira ith a remarkable observa- tional campaign that in- volved 12 telescopes both on the ground and in space, includ- ing three European Southern Obser- vatory (ESO) facilities, astronomers have uncovered the strange behav- iour of a pulsar, a super-fast-spin- ning dead star. This mysterious object is known to switch between two brightness modes almost con- stantly, something that until now has been an enigma. But as- tronomers have now found that sudden ejections of matter from the pulsar over very short periods are re- sponsible for the peculiar switches. “We have witnessed extraordinary cosmic events where enormous amounts of matter, similar to cosmic cannonballs, are launched into space within a very brief time span of tens of seconds from a small, dense celes- tial object rotating at incredibly high speeds,” says Maria Cristina Baglio, researcher at New York University Abu Dhabi, affiliated with the Ital- ian National Institute for Astro- physics (INAF), and the lead author of the paper published in Astron- omy & Astrophysics . A pulsar is a fast-rotating, magnetic, dead star that emits a beam of elec- NOVEMBER-DECEMBER 2023 ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 36 ﺗﻠﺴ ﻮ ﺎت اﻟ ﻤﺮﺻﺪ اﻟـﺠﻨﻮﺑﻲﺗﺴﺎﻋﺪ اﻷوروﺑ ﻓﻲ ﺣﻞ ﻟﻐﺰاﻟﻨ ﻢ ﻟﻨﺎ ﺾ : ﻘﻠﻢ ﺎر ﺮا ﻓ ﺮا - اﻟﻤﺮﺻﺪ اﻷوروﺑﻲ اﻟـﺠﻨﻮﺑﻲ ــــ ﺘﺘﺎﺗﺎﻏﺎ ـــ ﺣﻤﻠﺔ رﺻﺪ راﺋﻌـﺔ ﺷـﻤﻠﺖ 12 ﺗﻠﺴﻜﻮﺑ ﺎً ﻋﲆ اﻷرض وﰲ اﻟﻔﻀﺎء ﺑﻤﺎ ﰲ ذﻟﻚ ﺛﻼﺛﺔ ﻣﺮاﻓﻖ ﻟﻠﻤﺮﺻﺪ اﻷوروﺑﻲ ا ﻟﺠﻨﻮﺑﻲ اﻛﺘﺸﻒ ﻋﻠﻤﺎء اﻟﻔﻠﻚ اﻟﺴﻠﻮك اﻟﻐﺮﻳﺐ ﻟﻠﻨﺠﻢ اﻟﻨﺎﺑﺾ، وﻫﻮ ﻧﺠـﻢ ﻣﻴـﺖ ﻳـﺪور ﺑـ ـ ﴪﻋﺔ ﻓﺎﺋﻘ ـﺔ وﻣ ـﻦ ا ﻌ ـﺮوف أن ﻫ ـﺬا اﻟﺠﺴ ـﻢ اﻟﻐ ـﺎﻣﺾ ﻳﻘــﻮم ﺑﺎﻟﺘﺒــﺪﻳﻞ ﺑ ـ وﺿــﻌﻲ اﻟﺴﻄﻮع ﺑﺸﻜﻞ ﻣﺴﺘﻤﺮ ﺗﻘﺮﻳﺒﺎً وﻫﻮ اﻷﻣـﺮ اﻟﺬي ﻛﺎن ﻟﻐﺰاً . ﺣﺘﻰ اﻵن ﻟﻜﻦ ﻋﻠﻤﺎء اﻟﻔﻠﻚ وﺟﺪوا اﻵن أن اﻻﻧﺒﻌﺎﺛﺎت ا ﻔﺎﺟﺌﺔ ﻟﻠﻤﺎدة ﻣـﻦ اﻟﻔﻀـﺎء ﺣﺎﻟﻴـﺎً ﻳـﺘﻢ اﺳﺘﺨﺪام ) ﻛﺎﻣ ا دي ﻛﺎم ( ﻟﻠـﱪاﻣﺞ اﻟﺘـﻲ ﺗﻐﻄﻲ ﻧﻄﺎﻗﺎً واﺳﻌﺎً ﻣﻦ اﻟﻌﻠﻮم . ﻟﻜﻦ ﻋﻠﻤﺎء اﻟﻔﻠﻚ وﺟﺪوا اﻵن أن اﻻﻧﺒﻌﺎﺛـﺎت ا ﻔﺎﺟﺌﺔ ﻟﻠﻤﺎدة ﻣﻦ اﻟﻨﺠﻢ اﻟﻨـﺎﺑﺾ ﺧـﻼل ﻓـﱰات ﻗﺼـ ة ﺟـﺪًا ﻫـﻲ ا ﺴـﺆوﻟﺔ ﻋـﻦ ا ﻔﺎﺗﻴﺢ اﻟﻐﺮﻳﺒﺔ . ﺗﻘـﻮل ﻣﺎرﻳـﺎ ﻛﺮﻳﺴـﺘﻴﻨﺎ ﺑﺎﺟﻠﻴﻮ " : ﻟﻘﺪ ﺷـﻬﺪﻧﺎ أﺣـﺪاﺛًﺎ ﻛﻮﻧﻴـﺔ ﻏـ ﻋﺎدﻳﺔ ﺣﻴﺚ ﻳﺘﻢ إﻃﻼق ﻛﻤﻴﺎت ﻫﺎﺋﻠـﺔ ﻣـﻦ ا ـﺎدة ﺗﺸـﺒ ﻪ ﻗـﺬاﺋﻒ ا ـﺪﻓﻊ اﻟﻜﻮﻧﻴــﺔ إﱃ اﻟﻔﻀﺎء ﺧﻼل ﻓﱰة زﻣﻨﻴﺔ ﻗﺼ ة ﺟﺪ اً ﺗﺒﻠﻎ ﻋﴩات اﻟﺜﻮاﻧﻲ ﻣﻦ ﺟﺮم ﺳﻤﺎوي ﺻﻐ وﻛﺜﻴﻒ ﻳـﺪور ﺑـ ـ ﴪﻋﺎت ﻋﺎﻟﻴـﺔ ﺑﺸـﻜﻞ ﻻ ﻳﺼﺪق ﺔ ﺑﺎﺣﺜ ". ﰲ ﺟﺎﻣﻌﺔ ﻧﻴﻮﻳﻮرك أﺑﻮﻇﺒﻲ ﺗﺎﺑﻊ ﻟﻠﻤﻌﻬـﺪ اﻟـﻮﻃﻨﻲ اﻹﻳﻄـﺎﱄ ﻟﻠﻔﻴﺰﻳـﺎء اﻟﻔﻠﻜﻴﺔ وا ﺆﻟﻒ اﻟﺮﺋﻴﴘ ﻟﻠﻮرﻗﺔ ا ﻨﺸﻮرة ﰲ ﻋﻠﻢ اﻟﻔﻠﻚ واﻟﻔﻴﺰﻳﺎء اﻟﻔﻠﻜﻴﺔ . ﻧﻮﻓﻤﺒﺮ - ﺩﻳﺴﻤﺒﺮ 2 0 2 3 ﺎﺳﺘﺨﺪام