Free Astronomy Magazine May-June 2023 ARABIC VERSION

MAY-JUNE 2023 A rtwork: NASA, ESA, CSA, N. Bartmann (ESA/Webb), Martin Kornmesser (ESA), Serge Brunier (ESO), Nick Risinger (Photopic Sky Survey) Webb detects extremely small main belt asteroid by NASA/ESA/CSA Bethany Downer Christine Pulliam n asteroid roughly the size of Rome’s Colosseum — be- tween 300 to 650 feet (100 to 200 meters) in length — has been detected by an international team of European astronomers using NASA’s James Webb Space Telescope. Their project used data from the calibration of the Mid-In- fraRed Instrument (MIRI), in which the team serendipitously detected an interloping asteroid. The object is likely the smallest observed to date by Webb and may be an exam- ple of an object measuring under 0.6 miles (1 kilometer) in length within the main asteroid belt, lo- cated between Mars and Jupiter. More observations are needed to better characterize this object’s na- ture and properties. “We — completely unexpectedly — detected a small asteroid in publicly available MIRI calibration observa- tions,” explained Thomas Müller, an astronomer at the Max Planck Institute for Extraterrestrial Physics in Germany. “The measurements are some of the first MIRI measure- ments targeting the ecliptic plane and our work suggests that many new objects will be detected with this instrument.” These Webb observations, pub- lished in the journal Astronomy and Astrophysics , were not de- ﺗﻠﺴ ﻮب و ﺐ ﻜﺘﺸﻒ ﺎً ﺟﺮﻣ اً ﺻﻐ ﻓﻲ ﺣﺰام اﻟ ﻮ ﻜ ﺎت اﻟﺮ ﺴﻲ : ﻘﻠﻢ ﺑ ﺜﺎﻧﻲ داوﻧ ﺑﻮﻟ ﺎم ﺮ و ﻛﺮﺴﺘ و ﺎﻻ و ﺎ ﻧﺎﺳ ت اﻟﻔﻀﺎء اﻷوروﺑ ﺔ و اﻟﻜﻨﺪ ﺔ ـــــــــــ ﻔﺮﻳﻖ دوﱄ ﻣـﻦ ﻋﻠﻤـﺎء اﻟﻔﻠــﻚ اﻷوروﺑﻴ ﺑﺎﺳﺘﺨﺪام ﺗﻠﺴﻜﻮب ﺟﻴﻤﺲ وﻳﺐ اﻟﻔﻀـﺎﺋﻲ اﻟﺘ ـﺎﺑﻊ ﻟﻨﺎﺳـﺎ ﻛﻮﻳﻜﺒ ًـﺎ ﺑﺤﺠ ـﻢ اﻟﻜﻮﻟ ﻮﺳﻴﻮم ﰲ روﻣﺎ ﺗﻘﺮﻳﺒًﺎ - ﻳﱰاوح ﻃﻮﻟـﻪ ﺑ ٣٠٠ و ٦٥٠ ) ﻗـﺪﻣًﺎ ١٠٠ إﱃ ٢٠٠ (. ﻣـﱰ اﺳـﺘﺨﺪم ﻣﴩـوﻋﻬﻢ ﺑﻴﺎﻧـﺎت ﻣـﻦ ﻣﻌـﺎﻳﺮة ﻛ ـــﺎﻣ ا اﻷﺷ ـــﻌﺔ ﺗﺤ ـــﺖ اﻟﺤﻤ ـــﺮاء ا ﺘﻮﺳﻄﺔ (MIRI) ﺣﻴـﺚ اﻛﺘﺸـﻒ اﻟﻔﺮﻳـﻖ ﻣﺼﺎدﻓﺔً ﻛﻮﻳﻜﺒًﺎ ﻣﺘﺪاﺧﻼً ﻳ ﺤﺘﻤـﻞ أن ﻳﻜـﻮن اﻟﺠﺴﻢ ﻫﻮ اﻷﺻﻐﺮ اﻟﺬي ﺗﻢ رﺻﺪه ﺣﺘﻰ اﻵن ﺪ ﻳﻜﻮن ﻣﺜﺎﻻً ﻟﺠﺴﻢ ﻳﺒﻠﻎ اﻟﺠﺴﻢ ﻫﻮ اﻷﺻﻐﺮ اﻟﺬي ﺗﻢ رﺻﺪه ﺣﺘﻰ اﻵن ﺑﻮاﺳﻄﺔ ﺗﻠﺴﻜﻮب وﻳـﺐ وﻗـﺪ ﻳﻜـﻮن ﻣﺜـﺎﻻً ﻟﺠﺴﻢ ﻳﺒﻠـﻎ ﻃﻮﻟـﻪ أﻗـﻞ ﻣـﻦ ٠.٦ ) ﻣﻴـﻞ ١ ( ﻛﻴﻠﻮﻣﱰ داﺧﻞ ﺣﺰام اﻟﻜﻮﻳﻜﺒﺎت اﻟﺮﺋﻴـ ﴘ ـ اﻟﻮاﻗﻊ ﺑ ا ﺮﻳﺦ وا ﺸﱰي . ﻫﻨﺎك ﺣﺎﺟﺔ إﱃ ﺪ ﻣﻦ ﻣﺰﻳ اﻷرﺻﺎد ﻟﺘﻮﺻﻴﻒ أﻓﻀـﻞ ﻟﻄﺒﻴﻌـﺔ اﻟﺠﺮم ﻫﺬا وﺧﺼﺎﺋﺼﻪ . ﻳﻤﻜـﻦ اﻟﻌﺜـﻮر ﻋـﲆ ا ﻴﺎه اﻟﻐﺎزﻳﺔ ﺑﺎﺗﺠﺎه ﻣﺮﻛﺰ اﻷﻗﺮاص ﺑﺎﻟﻘﺮب ﻣﻦ اﻟﻨﺠﻢ ﺣﻴﺚ ﺗﻜﻮن أﻛﺜﺮ دﻓﺌًﺎ . وﻣـﻊ ذﻟـﻚ ﻓﺈن ﻫﺬه ا ﻨﺎﻃﻖ اﻟﻘﺮﻳﺒﺔ ﻣﺨﻔﻴـﺔ ﺑﻮاﺳـﻄﺔ ﻓﺈن ﻫﺬه ا ﻨﺎﻃﻖ اﻟﻘﺮﻳﺒﺔ ﻣﺨﻔﻴـﺔ ﺑﻮاﺳـﻄﺔ ﻗﺮص اﻟﻐﺒﺎر . أوﺿﺢ ﺗﻮﻣـﺎس ﻣـﻮﻟﺮ ، ﻋـﺎﻟﻢ اﻟﻔﻠﻚ ﰲ ﻣﻌﻬﺪ ﻣﺎﻛﺲ ﺑﻼﻧﻚ ﻟﻠﻔﻴﺰﻳﺎء ﺧـﺎرج اﻷرض ﰲ أ ﺎﻧﻴﺎ " : ﻟﻘﺪ اﻛﺘﺸﻔﻨﺎ - ﺑﺸﻜﻞ ﻏ ﻣﺘﻮﻗﻊ ﺗﻤﺎﻣًـﺎ - ﻛﻮﻳﻜﺒًـﺎ ﺻـﻐ ًا ﰲ أرﺻـﺎد ﻣﻌـــﺎﻳﺮة MIRI ا ﺘﺎﺣـــﺔ ﻟﻠﺠﻤﻬـــﻮر " . " اﻟﻘﻴﺎﺳﺎت ﻫﻲ ﺑﻌﺾ ﻗﻴﺎﺳﺎت MIRI اﻷوﱃ اﻟﺘـﻲ ﺗﺴـﺘﻬﺪف ﻣﺴــﺘﻮى ﻣﺴـ اﻟﺸـﻤﺲ وﻳﺸ ﻋﻤﻠﻨﺎ إﱃ أﻧﻪ ﺳﻴﺘﻢ اﻛﺘﺸـﺎف اﻟﻌﺪﻳـﺪ ـــ ﻣﻦ اﻟﻜﺎﺋﻨﺎت اﻟﺠﺪﻳﺪة ﺑﺎﺳـﺘﺨﺪام ﻫـﺬه - ﻣﺎﻳﻮ ﻳﻮﻧﻴﻮ 2023 ـــ اﻛﺘ ﺸﻒ