Free Astronomy Magazine March-April 2026 ARABIC VERSION

MARCH-APRIL2026 A pair ofdwarf galaxies engaged in a gravitationaldance byNASA/ESA/CSA NASAWebbMissionTeam heNASA/ESA/CSAJamesWebb Space Telescope has spied a pairofdwarfgalaxiesen- gaged in a gravitational dance. ThesetwogalaxiesarenamedNGC 4490andNGC4485,andthey’relo- cated about 24 million light-years awayintheconstellationCanesVe- natici (The Hunting Dogs). Aside from the Milky Way’s own dwarf companions (the Large and SmallMagellanicClouds),thisisthe closest known interacting dwarf- dwarf system where astronomers have directly observed both a gas bridge and resolved stellar popula- tions.TogetherNGC4490andNGC lionsofyearsagomight havegrown and evolved. The nearby dwarf galaxies NGC 4490 and NGC 4485 formanintriguingpair. Nearlythree decades ago, astronomers discov- eredawispybridgeofga sconnect-ing the two galaxies, showing that they have interacted in the past. Despitemanystudiesw ithpowerful telescopes like the NASA/ESA Hub- bleSpaceTelescope,th ehistorybe-tween NGC4490 and NGC 4485 has remained mysterious. Recently, Webb observed this curi- ousgalacticpairaspartoftheFeed-back in Emerging extrAgalactic Star clusTers (FEAST) programme. The FEAST programme used Webb’s sen- sitiveinfraredeyestorevealthefor- mation of new stars in different types of nearby galaxies. ﻣﺠﻠﺔ FreeAstronomy ﺎﻟﻌﺮ ﺔ 20 زوجﻣﻦ اﻟﻤﺠﺮات اﻟﻘﺰﻣﺔ ﻓﻲﺗﻔﺎﻋﻞﺟﺎذﺑﻲﻣﺘ ﺎدل : ﻘﻠﻢ ﻓﺮﻖ ﻣﻬﻤﺔ ﺗﻠﺴ ﻮب و ﺐ و ﺎﻟﺔ ﻧﺎﺳﺎ / و ﺎﻟﺔ إ ﺴﺎ / و ﺎﻟﺔ اﻟﻔﻀﺎء اﻟﻜﻨﺪ ﺔ رﺻـﺪ ﺗﻠﺴـﻜﻮب ﺟـﻴﻤﺲ وﻳــﺐ اﻟﻔﻀــﺎﺋﻲ اﻟﺘﺎﺑﻊ ﻟﻨﺎﺳﺎ ووﻛـﺎﻟﺘﻲ اﻟﻔﻀـﺎء اﻷوروﺑﻴـﺔ واﻟﻜﻨﺪﻳﺔ زوﺟًﺎ ﻣﻦ ا ﺠﺮات اﻟﻘﺰﻣ ﺔ ﰲ ﺣﺎﻟﺔ ﺗﻔﺎﻋـﻞ ﺟـﺎذﺑﻲ ﻣﺘﺒ ـﺎدل ﺗ. ﻌ ـﺮف ﻫﺎﺗ ـﺎن ا ﺠﺮﺗﺎن ﺑﺎﺳـﻢ NGC 4490 و NGC 4485 وﺗﻘﻌﺎن ﻋﲆ ﺑُﻌﺪ ﻳﻘـﺎرب 24 ﻣﻠﻴـﻮن ﺳـﻨﺔ ﺿــﻮﺋﻴﺔ ﰲ اﺗ ﺠــﺎه ﻛﻮﻛﺒــﺔ اﻟﺴــﻠﻮﻗﻴﺎن . ﺑﺎﺳﺘﺜﻨﺎء ا ﺠﺮات اﻟﻘﺰﻣـﺔ اﻟﺘﺎﺑﻌـﺔ ﻟـﺪرب اﻟﺘﺒﺎﻧ )ﺔ ﺳﺤﺎﺑﺘﺎ ﻣﺎﺟﻼن اﻟﻜﱪى واﻟﺼﻐﺮى ( ﻳ ﻌﺪ ﻫﺬا أﻗﺮب ﻧﻈﺎم ﻣﻌﺮوف ﻣﻦ ﻧﻮع ﻗﺰم – ﻗﺰم ﻣﺘﻔﺎﻋﻞ ﺗﻤﻜّﻦ ﻓﻴﻪ اﻟﻔﻠﻜﻴﻮن ﻣﻦ رﺻﺪ ـﺟـ ﴪ ﻏـﺎزي ﺑـ ا ﺠـﺮﺗ ﻣـﻊ ﺗﻤﻴﻴـﺰ اﻟﺘﺠﻤﻌﺎت اﻟﻨﺠﻤﻴﺔ ﻓﺮادى وﺗﺸﻜﻞ ا ﺠﺮﺗﺎن ﺎً ﻣﻌ اﻟﻨﻈﺎم ا ﻌﺮ وف ﺑﺎﺳﻢ Arp 269 ا ﺪرج ﺿﻤﻦ أﻃﻠﺲ ا ﺠﺮات اﻟﺸﺎذة . وﺑﺴﺒﺐ ﻗﺮب ا ﺴﺎﻓﺔ ﻧﺴﺒﻴًﺎ، إﺿﺎﻓﺔً إﱃ ﻗﺪرة وﻳﺐ اﻟﻌﺎﻟﻴﺔ ﺿﻤﻦ أﻃﻠﺲ ا ﺠﺮات ﻏ ا ﻨﺘﻈﻤﺔ وﺑﺴﺒﺐ ﻗ ـﺮب ا ﺴ ـﺎﻓﺔ ﻧﺴ ـﺒﻴ ﺎً إﺿـﺎﻓﺔً إﱃ ﻗ ـﺪرة ﺗﻠﺴﻜﻮب وﻳﺐ اﻟﻌﺎﻟﻴﺔ ﻋﲆ اﺧﱰاق اﻟﺴـﺤﺐ اﻟﻜﻮ ﻧﻴـﺔ ا ﻐـﱪة ﰲ ﻧﻄـﺎق اﻷﺷـﻌﺔ ﺗﺤـﺖ اﻟﺤﻤﺮاء ﺗﺘﻴﺢ ﻫﺎﺗﺎن ا ﺠﺮﺗﺎن ﻓﺮﺻﺔ ﻓﺮﻳﺪة ﻟﺪراﺳﺔ أﻧﻤـﺎط اﻟﺘﻔـﺎﻋﻼت ا ﺠﺮﻳـﺔ اﻟﺘـﻲ ﻛﺎﻧﺖ ﺷﺎﺋﻌﺔ ﻗﺒﻞ ﻣﻠﻴﺎرات اﻟﺴﻨ . ﺗﺸﱰك ا ﺠﺮات اﻟﻘﺰﻣﺔ ﰲ ﺧﺼﺎﺋﺺ ﻋﺪﻳﺪة ﻣﻊ ا ﺠﺮات اﻟﻔﺘﻴﺔ ﰲ اﻟﻜﻮن ا ﺒﻜﺮ ﻓﻬﻲ أﻗﻞ ﻛﺘﻠﺔ ﺑﻜﺜ ﻣﻦ ﻣﺠﺮات ﻣﺜـﻞ درب اﻟﺘﺒﺎﻧـﺔ وﺗﺤﺘ ﻮي ﻋﺎدة ﻋﲆ ﻧﺴـﺐ ﻣﻨﺨﻔﻀـﺔ ﻣـﻦ اﻟﻌﻨﺎﴏ اﻟﺜﻘﻴﻠﺔ ) اﻟﺘﻲ ﻳﺴﻤﻴﻬﺎ ﻋﻠﻤﺎء اﻟﻔﻠﻚ اﻟﻌﻨﺎﴏ اﻷﺛﻘﻞ ﻣﻦ اﻟﻬﻠﻴ ﻛ(ﻮم ﻤﺎ أﻧﻬﺎ ﻏﻨﻴﺔ ﺑﺎﻟﻐـﺎز وﻓﻘـ ة ﻧﺴـﺒﻴ ﺎً ﺑـﺎﻟﻨﺠﻮم . ﻋﻨـﺪﻣﺎ ﺗﺘﺼﺎدم ا ﺠﺮات اﻟﻘﺰﻣﺔ اﻟﻘﺮﻳﺒﺔ أو ﺗ ﻨـﺪﻣﺞ أو ﺗﺘﺒﺎدل اﻟﻐﺎز ﻓﻴﻤـﺎ ﺑﻴﻨﻬـﺎ ﻓﺈﻧﻬـﺎ ﺗﻘـﺪم ﻧﻤﻮذﺟًﺎ ﻟﻔﻬﻢ ﻛﻴﻔﻴﺔ ﻧﻤﻮ ا ﺠﺮات وﺗﻄﻮ رﻫﺎ ﰲ اﻟﻌﺼﻮر اﻟﻜﻮﻧﻴﺔ ا ﺒﻜـﺮة وﻳ ﻌـﺪ اﻟﻨﻈـﺎم NGC 4490 / NGC 4485 ﻣﺜـﺎﻻً اً ﻣﺜـ ﻟﻼﻫﺘﻤﺎم إذ اﻛﺘﺸﻒ ﻋﻠﻤﺎء اﻟﻔﻠﻚ ﻗﺒﻞ ﻧﺤـﻮ ﺛﻼﺛﺔ ﻋﻘﻮد ﺟﴪ اً ﺎً ﻏﺎزﻳ ﺎً ﺧﺎﻓﺘ ﻳﺼـﻞ ﺑـ ا ﺠﺮﺗ ﻣﺎ ﻳﺪل ﻋﲆ ﺣﺪوث ﺗﻔﺎﻋـﻞ ﺳـﺎﺑﻖ ﺑﻴﻨﻬﻤﺎ ﻛﻤﺎ ﺗﺸ اﻟﺒﻨﻰ اﻟ ﻨﺠﻤﻴـﺔ ا ﺸـﻮﻫﺔ وﻣﻨﺎﻃﻖ ﺗﺸﻜﻞ اﻟﻨﺠﻮم اﻟﻨﺸﻄﺔ اﱃ ﺗﺎﺛ ات ﻣﺪﻳﺔ واﺿﺤﺔ ﺣﺘﻰ اﻟﻴﻮم ورﻏﻢ اﻟﺪراﺳـﺎت اﻟﻌﺪﻳـﺪة ﺑﺎﺳـﺘﺨﺪام ﻣﺮا ﺻــﺪ ﻗﻮﻳـﺔ ﻣﺜــﻞ ﺗﻠﺴﻜﻮب ﻫﺎﺑﻞ اﻟﻔﻀﺎﺋﻲ ﻇﻠـﺖ اﻟﺘﻔﺎﺻـﻴﻞ اﻟﺘﺎرﻳ ﺨﻴﺔ ﻟﺘﻔﺎﻋﻠﻬﻤﺎ ﻏ واﺿﺤﺔ . ﻣﺆﺧﺮاً رﺻﺪ ﺗﻠﺴﻜﻮب وﻳـﺐ ﻫـﺬا اﻟﻨﻈـﺎم ﺿﻤﻦ ﺑﺮﻧﺎﻣﺞ ) ﻓﻴﺴﺖ ﻋﻤﻠﻴﺎت اﻟﺘﻐﺪﻳـﺔ ﰲ اﻟﻌﻨ ﺎﻗﻴﺪ اﻟﻨﺠﻤﻴﺔ اﻟﻨﺎﺷﺌﺔ ﰲ ﻣﺠﺮات ﻗﺮﻳﺒﺔ ( و اﺳﺘﺨﺪم ﺣﺴﺎﺳﻴﺔ وﻳﺐ ﰲ اﻷﺷـﻌﺔ ﺗﺤـﺖ اﻟﺤﻤﺮاء ﻟﻠﻜﺸﻒ ﻋﻦ ﺗﺸﻜﻞ ﻧﺠﻮم ﺟﺪﻳﺪة ﰲ أﻧﻮاع ﻣﺨﺘﻠﻔﺔ ﻣﻦ ا ﺠﺮات اﻟﻘﺮﻳﺒﺔ . ” - ﻣﺎﺭﺱ ﺃﺑﺮﻳﻞ 2 0 2 6