Free Astronomy Magazine July-August 2023 ARABIC VERSION

The star eventually grows to entirely engulf the orbiting planet, triggering an outburts that can be detected from Earth. “With these revolutionary new opti- cal and infrared surveys, we are now witnessing such events happen in real time in our own Milky Way — a testament to our almost certain fu- ture as a planet,” said Kishalay De, an astronomer at the Massachusetts Institute of Technology and lead au- thor on the paper. The outburst from the engulfment lasted approximately 100 days and the characteristics of its lightcurve, as well as the ejected material, gave astronomers insight into the mass of the star and that of its engulfed planet. The ejected material con- sisted of about 33 Earth masses of hydrogen and about 0.33 Earth masses of dust. “That’s more star- and planet-forming material being recycled, or burped out, into the in- terstellar medium thanks to the star eating the planet,” said Lau. From this analysis, the team estimated that the progenitor star is about 0.8−1.5 times the mass of our Sun and the engulfed planet was 1−10 times the mass of Jupiter. Now that the signatures of a plane- tary engulfment have been identi- fied for the first time, astronomers have improved metrics they can use to search for similar events happen- ing elsewhere in the cosmos. This will be especially important when Vera C. Rubin Observatory comes on line in 2025. For instance, the ob- served effects of chemical pollution on the remnant star when seen else- where can hint that an engulfment has taken place. The interpretation of this event also provides evidence for a missing link in our understanding of the evolu- tion and final fates of planetary sys- tems, including our own. “I think there’s something pretty re- markable about these results that speaks to the transience of our exis- tence,” says Lau. “After the billions of years that span the lifetime of our Solar System, our own end stages will likely conclude in a final flash that lasts only a few months.”     اﻟــــﻨ ﻢ ـــــﺔ ﻟﻴ ﺘﻠــــﻊ ﻨﻤـــــﻮ ﻓــــﻲ اﻟﻨﻬﺎ ــــﺪور اﻟ ﻮﻛـــــﺐ اﻟــــﺬ إﻟـــﻰ اﻧـــﺪﻻع اﻧﻔﺠــــﺎرات ﻓـــﻲﻣـــﺪارﻩ ﺎﻟ ﺎﻣـــﻞ ﻣﻤــــﺎ ﻳـــﺆد ﻤﻜﻦ اﻛﺘﺸﺎﻓﻬﺎ ﻣﻦ اﻷرض . ﻗـﺎل ﻛﻴﺸـﺎﻻي دي ﻋـﺎﻟﻢ اﻟﻔﻠـﻚ ﰲ ﻣﻌﻬـﺪ ﻣﺎﺳﺎﺗﺸﻮﺳــﺘﺲ ﻟﻠﺘﻜﻨﻮﻟﻮﺟﻴــﺎ وا ﺆﻟــﻒ اﻟﺮﺋﻴﴘ ﻠﻮرﻗ ﻟ : "ﺔ ﻣﻦ ﺧﻼل ﻫﺬه ا ﺴـﻮﺣﺎت اﻟﻀﻮﺋﻴﺔ واﻷﺷ ﻌﺔ ﺗﺤـﺖ اﻟﺤ ﻤـﺮاء اﻟﺜﻮرﻳـﺔ اﻟﺠﺪﻳﺪة ﻧﺸﻬﺪ اﻵن ﻣﺜﻞ ﻫﺬه اﻷﺣﺪاث ﺗﺤﺪث ﰲ اﻟﻮﻗ ﺖ اﻟﻔﻌﲇ ﰲ ﻣﺠﺮﺗﻨﺎ درب اﻟﺘﺒﺎﻧﺔ وﻫﻲ ﺷﻬﺎدة ﻋﲆ ﻣﺴﺘﻘﺒﻠﻨﺎ ﺷﺒﻪ ا ﺆﻛﺪ ﻛﻜﻮﻛﺐ ." اﺳﺘﻤﺮ اﻻﻧﻔﺠﺎر اﻟﻨﺎﺟﻢ ﻋﻦ اﺑـﺘﻼع اﻟﻜﻮﻛـﺐ ﺣﻮاﱄ 100 ﻳﻮم وأﻋﻄﺖ ﺧﺼـﺎﺋﺺ ﻣﻨﺤﻨـﻰ اﻟﻀﻮء وﻛﺬﻟﻚ ا ﺎدة ا ﻘﺬوﻓﺔ ﻋﻠﻤـﺎء اﻟﻔﻠـﻚ ﻧﻈﺮة ﺛﺎﻗﺒﺔ ﻟ ﻜﺘﻠﺔ اﻟﻨﺠﻢ وﻛﻮﻛﺒـﻪ اﻟـﺬي ﺗـﻢ اﺑﺘﻼﻋﻪ . ا ﺎدة ا ﻘﺬوﻓﺔ ﺗﺘﻜﻮن ﻣﻦ ﺣﻮاﱄ 33 ﻛﺘﻠﺔ أرﺿﻴﺔ ﻣﻦ اﻟﻬﻴـﺪروﺟ وﺣـﻮاﱄ 0.33 ﻛﺘﻠﺔ أرﺿﻴﺔ ﻣﻦ اﻟﻐﺒﺎر . ﻗﺎل ﻻو " : ﻫـﺬا ﻫـﻮ ﻳﻮﻟﻴﻮ - ﺃﻏﺴﻄﺲ 2 0 2 3 ا ﺰﻳﺪ ﻣﻦ ا ﻮاد ا ﻜﻮﻧـﺔ ﻟﻠﻨﺠـﻮم واﻟﻜﻮاﻛـﺐ اﻟﺘﻲ ﻳـﺘﻢ إﻋـﺎدة ﺗـﺪوﻳﺮﻫﺎ أو اﻧﻔﺠﺎرﻫـﺎ ﰲ اﻟﻮﺳﻂ ﺑ اﻟﻨﺠﻮم ﺑﻔﻀﻞ اﻟﻨﺠﻢ اﻟﺬي ﻳﺄﻛـﻞ اﻟﻜﻮﻛﺐ ﻣﻦ ". ﻫﺬا اﻟﺘﺤﻠﻴﻞ اﺳﺘﻄﺎع اﻟﻔﺮﻳـﻖ أن اﻟﻨﺠﻢ اﻟﺴﻠﻒ ﺗﺒﻠﻎ ﻛﺘﻠﺘﻪ ﺣـﻮاﱄ 0.8−1.5 ﻣﺮة ﻣﻦ ﻛﺘﻠﺔ اﻟﺸـﻤﺲ وأن اﻟﻜﻮﻛـﺐ اﻟـﺬي اﺑﺘﻠﻊ ﻳﺴﺎوي 1−10 أﺿـﻌﺎف ﻛﺘﻠـﺔ ﻛﻮﻛـﺐ ا ﺸـﱰي . واﻵن ﺑﻌــﺪ أن ﺗـﻢ اﻟﺘﻌـﺮف ﻋـﲆ ﺑﺼﻤﺎت اﻻﺑـﺘﻼع اﻟﻜـﻮﻛﺒﻲ ﻷول ﻣـﺮة ﻗـﺎم ﻋﻠﻤﺎء ا ﻟﻔﻠﻚ ﺑﺘﺤﺴ ا ﻘﺎﻳﻴﺲ اﻟﺘﻲ ﻳﻤﻜﻨﻬﻢ اﺳﺘﺨﺪاﻣﻬﺎ ﻟﻠﺒﺤﺚ ﻋﻦ أﺣﺪاث ﻣﻤﺎﺛﻠ ﺔ ﺗﺤﺪث ﰲ ﻣﻜﺎن آﺧﺮ ﻣﻦ اﻟﻜﻮن ﻫﺬا و ﻣﻬﻤًﺎ ﺳﻴﻜﻮن ﺑﺸﻜﻞ ﺧﺎص ﻋﻨﺪﻣﺎ ﻳﺘﻢ ﺗﺸﻐﻴﻞ ﻣﺮﺻﺪ ﻓـ ا ﰲ ﻋــﺎم ﳼ روﺑــ 2025 ﻓ ﻌــﲆ ﺳــﺒﻴﻞ اﻟﺘﺄﺛ ات ا ﺮﺻﻮدة ﻟﻠﺘﻠﻮث اﻟﻜﻴﻤﻴـﺎﺋﻲ ﻋـﲆ اﻟﻨﺠﻢ ا ﺘﺒﻘﻲ ﻋﻨﺪ رﺻﺪه ﰲ ﻣﻜﺎن آﺧـﺮ ﻣـﻦ اﻟﻜﻮن ﺣﻴﺚ ﻳﻤﻜﻦ أن ﻳﺸ ذﻟـﻚ إﱃ ﺣـﺪوث اﺑﺘﻼع ﻟﻜﻮﻛﺐ . ﻳﻮﻓﺮ ﺗﻔﺴ ﻫﺬا اﻟﺤـﺪث أﻳﻀًـﺎ دﻟـﻴﻼً ﻋـﲆ وﺟﻮد راﺑﻂ ﻣﻔﻘﻮد ﰲ ﻓﻬﻤﻨﺎ ﻟﺘﻄﻮر أ ﻧﻈﻤـﺔ اﻟﻜﻮاﻛﺐ وﻣﺼﺎﺋﺮﻫﺎ اﻟﻨﻬﺎﺋﻴـﺔ ﺑﻤـﺎ ﰲ ذﻟـﻚ ﻧﻈﺎﻣﻨﺎ اﻟﺸﻤﴘ . ﻳﻘﻮل ﻻو " : أﻋﺘﻘـﺪ أن ﻫﻨـﺎك ﺷـﻴﺌًﺎ ﻳﻤﻜـﻦ ﺗﻤﻴﻴﺰه إﱃ ﺣـﺪ ﻛﺒـ ﺑﺸـﺄن ﻫـﺬه اﻟﻨﺘـﺎﺋﺞ ﻳﺘﺤ ﺪث ﻋﻦ زوال وﺟﻮدﻧـﺎ " ." ﺑﻌـﺪ ﻣﻠﻴـﺎرات اﻟﺴﻨ ﻣـﻦ ﻋﻤـﺮ ﻧﻈﺎﻣﻨـﺎ اﻟﺸـ ـ ﻤﴘ ﻣـﻦ ا ﺤﺘﻤﻞ أن ﺗﻨﺘﻬ ا ﺮاﺣﻞ ﻲ اﻟﻨﻬﺎﺋﻴﺔ ﰲ وﻣﻀﺔ ﺗﺘﺠﺎوز ﻻ ﺑﻀﻌﺔ أﺷﻬﺮ .