Free Astronomy Magazine September-October 2024

hisgraphicpresentssomeoftheresultsfromtheMIRIMid-INfraredDiskSurvey(MINDS),whichaimstobuildabridgebetweenthechemicalin- ventory of disks and the properties of exoplanets. In a new study, a science team explored the region around a very low-mass star of 0.11 solar masses(knownasISO-ChaI147).Theyfoundthatthegasintheplanet-formingregionofthestarisrichincarbon.Thiscouldmeanthatthebuild- ing blocks for planets may lack carbon because all of the carbon-containing chemicals have evaporated and been lost into the surrounding gas. As a result, any rocky planets that form might be carbon-poor. The spectrum revealed by NASA’s James Webb Space Telescope’s MIRI (Mid-Infrared In- strument) shows the richest hydrocarbon chemistry seen to date in a protoplanetary disk, consisting of 13 carbon-bearing molecules. This includesthe first extrasolar detection of ethane (C 2 H 6 ). The team also successfully detected ethylene (C 2 H 4 ), propyne (C 3 H 4 ), and the methyl radical CH 3 , forthefirsttimeinaprotoplanetarydisk.Thisgraphichighlightsthedetectionsofethane(C 2 H 6 ),methane(CH 4 ),propyne(C 3 H 4 ),cyanoacetylene (HC 3 N), and the methyl radical CH 3 . [NASA, ESA, CSA, Ralf Crawford (STScI)] team’s findings include the first de- tection of ethane (C 2 H 6 ) outside of our solar system, as well as ethyl- ene (C 2 H 4 ), propyne (C 3 H 4 ), and the methyl radical CH 3 . “Thesemoleculeshavealreadybeen detectedinoursolarsystem,likein comets such as 67P/Churyumov– Gerasimenko and C/2014 Q 2 (Love- joy),” added Arabhavi. “Webb al- lowed us to understand that these hydrocarbonmoleculesarenotjust diverse but also abundant. It is amazing that we can now see the dance of these molecules in the planetarycradles.Itisaverydiffer- ent planet-forming environment than we usually think of.” Theteamindicatesthattheseresults have large implications for the chemistry of the inner disk and the planets that might form there. Since Webb revealed the gas in the disk is sorichincarbon,thereislikelylittle carbonleftinthesolidmaterials thatplanetswouldformfrom.Asa result,theplanetsthatmightform there may ultimately be carbon- poor.(Earthitselfisconsideredcar- bon-poor.) “This is profoundly different from the composition we see in disks around solar-type stars, where oxy- gen bearing molecules like waterand carbon dioxide dominate,” added team member Inga Kamp,also of the University of Groningen. “This object establishes that these are a unique class of objects.” “It’s incredible that we can detect and quantify the amount of mole- cules that we know well on Earth, suchasbenzene,inanobjectthatis more than 600 light-years away,” addedteammemberAgnésPerrin of Centre National de la Recherche Scientifique in France. Next,thescienceteamintendstoex- pandtheirstudytoalargersample ofsuchdisksaroundverylow-mass starstodeveloptheirunderstanding ofhowcommonorexoticsuchcar- bon-rich terrestrial planet-forming regions are. “Theexpansionofourstudywill also allow us to better understand how these molecules can form,” ex- plainedteammemberandprinci- pal investigator of the MINDS pro-gram, Thomas Henning, of the Max- Planck- InstituteforAstronomyin Germany. “Several features in the Webbdataarealsostillunidentified, so more spectroscopy is required to fully interpret our observations.” This work also highlights the crucial needforscientiststocollaborate acrossdisciplines.Theteamnotes that these results and the accompa- nying data can contribute towards otherfieldsincludingtheoretical physics, chemistry, and astrochem- istry,tointerpretthespectraand to investigate new features in thiswavelengthrange.     ﻌــﺮض ﻫــﺬا اﻟﺮﺳـــﻢ ﻌﻀــ ﺎ ﻣــﻦ ﻧﺘـــﺎﺋﺞ ﻣﺴــﺢ اﻟﻘــﺮص ﺎﻷﺷـــﻌﺔ ﺗﺤــﺖ ا ﻤــﺮاء اﻟﻤﺘﻮﺳـــﻄﺔ ) MINDS ( ــﺎﺋﻲ ﻟﻸﻗـــﺮاصوﺧﺼــﺎﺋﺺ اﻟ ﻮاﻛــﺐ اﻟﻤﺨــﺰون اﻟﻜ ﻤ ﻳﻬــﺪف إﻟـــﻰ ﻨــﺎء ﺟﺴــﺮﺑـــ واﻟــﺬ ـــﺔ اﻟﻨ ﻤ . اﺳﺘﻜﺸـﻒﻓﺮ ـﻖ ﻋﻠﻤـﻲ ــﺪة ﻓــﻲ دراﺳـﺔ ﺟﺪ ـﺔ ﺗ ﻠــﻎ ـﻨ ﻢ ﻣــﻨﺨﻔﺾ اﻟﻜﺘﻠــﺔ ﻟﻠﻐﺎ اﻟﻤﻨﻄﻘـﺔ اﻟﻤﺤ ﻄــﺔ 0.11 ﻛﺘﻠـﺔ ﺷﻤﺴــ ﺔ ) اﻟﻤﻌـﺮوف ﺎﺳـﻢ ISO-ChaI147 و ( وﺟـﺪوا أن اﻟﻐــﺎز اﻟﻤﻮﺟـﻮد ﻓــﻲﻣﻨﻄﻘــﺔ ﺗﺸ ـﺎﻟﻜﺮﻮن ﻞ اﻟ ﻮاﻛﺐ ﻓﻲ اﻟـﻨ ﻢ ﻏـ ﺗﺤﺘـﻮ ـﺔ اﻟـ ﻫـﺬا أن اﻟﻠ ﻨـﺎت اﻷﺳﺎﺳـ ﺔ ﻟﻠ ﻮاﻛـﺐ ﻗـﺪ ﺗﻔﺘﻘـﺮ إﻟـﻰ اﻟﻜﺮـﻮن ﻷن ﻤﻴـﻊ اﻟﻤـﻮاد اﻟﻜ ﻤ ﺎﺋ وﻗـﺪ ﻌـ يﻋﻠـﻰ اﻟﻜﺮـﻮن ﺗﺤﺘـﻮيﻋﻠـﻰ اﻟﻜﺮـﻮن ﺗﺒﺨـﺮ وﻓﻘﺪت ﻓﻲ اﻟﻐ ﺎزاﻟﻤﺤ ﻂ ﺑﻬﺎ وﻧﺘﻴﺠﺔ ﻟﺬﻟﻚ، ﻓﺈن أي ﻮاﻛﺐﺻﺨﺮ ﺔ ﺗﺘﺸ ﻞ ﻗﺪ ﺗ ﻮن ﻓﻘ ة ﺎﻟﻜﺮﻮن . ﻛﺸﻔﺖ ﻋﻨﮫ أداة ُﻈﻬﺮ اﻟﻄ ﻒ اﻟﺬ MIRI ) أداة اﻷﺷﻌﺔ ﺗﺤﺖ اﻟ ـ ﻤﺮاء اﻟﻤﺘﻮﺳـﻄﺔ ( اﻟﺘﺎ ﻌـﺔ ﻟﺘﻠﺴ ﻮ ب ﺟ ﻤﺲو ﺐ اﻟﻔﻀﺎﺋﻲ اﻟﺘﺎﺑﻊ ﻟﻨﺎﺳﺎ ﻛ ﻤ ﺎء ﻫ ﺪروﻛﺮﻮﻧ ﺔ ﺷ أﻏ أوﻟﻲ اﻵن ﻓﻲﻗﺮص ﻮﻛ ﻮﻫﺪتﺣ ﺘ ﻮ ن ﻣﻦ 13 ﺎً ﺟﺰ ﺌ ﺣﺎﻣﻼً ﻟﻠﻜﺮﻮن و ﺘﻀﻤﻦ ذﻟﻚ أول اﻛﺘﺸﺎفﺧﺎرج اﻟﻤ ﻤﻮﻋـﺔ اﻟﺸﻤﺴـ ﺔ ﻟﻺ ﺜــﺎن ) C2H6 .( ــﺢ اﻟﻔﺮ ـﻖ أ ﻀــ ﻧﺠ ﺎً ﻓــﻲ اﻛﺘﺸـﺎف اﻹ ﺜ ﻠــ ) C2H4 ( واﻟ وﺑــ ) C3H4 ( وﺟــﺬر اﻟﻤ ﺜﻴــﻞ ) CH3 ( اﻷوﻟــﻲ ــﻮﻛ ﻷول ﻣــﺮة ﻓــﻲ اﻟﻘــﺮص اﻟ . ﺴــﻠﻂﻫــﺬا اﻟﺮﺳــﻢ اﻟﻀــﻮء ﻋﻠــﻰ اﻛﺘﺸﺎﻓﺎت ﻏﺎزاﻟﻤ ﺜﺎن ) C2H6 ( واﻟﻤ ﺜﺎن ) CH4 ( واﻟ وﺑ ) C3H4 ( وﺳ ﺎﻧﻮ أﺳ ﺘ ﻠ ) HC3N ( وﺟﺬر اﻟﻤ ﺜﻴﻞ CH3 ] . NASA, ESA, CSA, Ralf Crawford (STScI [( - ﺳﺒﺘﻤﺒﺮ ﺃﻛﺘﻮﺑﺮ 2 0 2 4 ﺗﺘﻀﻤﻦ اﻟﻨﺘﺎﺋﺞ اﻟﺘﻲ ﺗﻮﺻﻞ إﻟﻴﻬﺎ اﻟﻔﺮﻳﻖ أول اﻛﺘﺸﺎف ﻟﻺﻳﺜـﺎن (C2H6) ﺧـﺎرج ﻧﻈﺎﻣﻨـﺎ اﻟﺸﻤـ ﴘـ ﺑﺎﻹﺿـﺎﻓﺔ إﱃ اﻹﻳﺜﻴﻠـ (C2H4) واﻟﱪوﺑ (C3H4) وﺟﺬر ا ﻴﺜﻴﻞ CH3 . أ وأﺿﺎف ": رﺑﻬﺎﰲ ﻟﻘﺪ ﺗﻢ ﺑﺎﻟﻔﻌـﻞ اﻛﺘﺸـﺎ ف ﻫﺬه اﻟﺠﺰﻳﺌﺎت ﰲ ﻧﻈﺎﻣﻨﺎ اﻟﺸﻤﴘ ﻛﻤﺎ ﻫـﻮ اﻟﺤــﺎل ﰲ ا ــﺬﻧﺒﺎت ﻣﺜــﻞ ﺗﺸــﻮرﻳﻮﻣﻮف - ﺟ اﺳﻴﻤﻨﻜﻮ و ﻟﻮف ﺟﻮي ) Q2 .( ﻟﻘﺪ أﺗﺎح ﻟﻨﺎ ﺗﻠﺴﻜﻮب وﻳﺐ أن ﻧﻔﻬﻢ أن ﻫـﺬه اﻟﺠﺰﻳﺌﺎت اﻟﻬﻴﺪروﻛﺮ ﺑﻮﻧﻴـﺔ ﻟﻴﺴـﺖ ﻣﺘﻨﻮﻋـﺔ ﻓﺤﺴﺐ ﺑﻞ وﻓ ة أﻳﻀًﺎ وﻣـﻦ ا ـﺪﻫﺶ أﻧﻨـﺎ ﻧﺴﺘﻄﻴﻊ اﻵن رؤﻳﺔ رﻗﺼﺔ ﻫﺬه ا ﻟﺠﺰﻳﺌﺎت ﰲ ا ﻬﺪ اﻟﻜـﻮﻛﺒﻲ . إﻧﻬـﺎ ﺑﻴﺌـﺔ ﺗﺸـﻜﻞ ﻛﻮﻛـﺐ ﻣﺨﺘﻠﻔﺔ ﺗﻤﺎﻣﺎ ﻋﻤﺎ ﻧﻔﻜﺮ ﻓﻴﻪ ﻋﺎدة . وﻳﺸ اﻟﻔﺮﻳﻖ إﱃ أن ﻫﺬه اﻟﻨﺘﺎﺋﺞ ﻟﻬـﺎ آﺛـﺎر ﻛﺒ ة ﻋﲆ ﻛﻴﻤﻴﺎء اﻟﻘﺮص اﻟﺪاﺧﲇ واﻟﻜﻮاﻛﺐ اﻟﺘﻲ ﻗﺪ ﺗﺘﺸ ﻜﻞ ﻫﻨـﺎك وﺑﻤـﺎ أن ﺗﻠﺴـﻜﻮب وﻳﺐ ﻛﺸﻒ أن اﻟﻐﺎز ا ﻮﺟﻮد ﰲ اﻟﻘﺮص ﻏﻨﻲ ﺟﺪًا ﺑﺎﻟﻜﺮﺑﻮن ﻓﻤﻦ ا ﺤﺘﻤﻞ أن ﻳﻜﻮن ﻫﻨـﺎك اﻟﻘﻠﻴﻞ ﻣﻦ اﻟﻜﺮﺑﻮن ا ﺘﺒﻘﻲ ﰲ ا ﻮاد اﻟﺼـﻠﺒﺔ وﻧﺘﻴﺠﺔ ﻟﺬﻟﻚ، ﻓﺈن اﻟﻜﻮاﻛﺐ اﻟﺘﻲ ﻗﺪ ﺗﺘﺸـﻜﻞ ﻫﻨﺎك ﻗـﺪ ﺗﻜـﻮن ﰲ ﻧﻬﺎﻳـﺔ ا ﻄـﺎف ﻓﻘـ ة ﻫﻨﺎك ﻗـﺪ ﺗﻜـﻮن ﰲ ﻧﻬﺎﻳـﺔ ا ﻄـﺎف ﻓﻘـ ة ﺑــﺎﻟﻜﺮﺑﻮن ) اﻷرض ﻧﻔﺴــﻬﺎ ﺗﻌﺘ ـﱪ ﻓﻘ ـ ة ﺑﺎﻟﻜﺮﺑﻮن .( أﺿﺎﻓﺖ إﻧﺠﺎ ﻛﺎﻣﺐ ﻋﻀﻮ اﻟﻔﺮﻳﻖ ﺎً ﻳﻀ وﻫﻲ أ ﻣﻦ ﺟﺎﻣﻌﺔ ﺟﺮوﻧﻴﻨﺠﻦ " : ﻫﺬا ﻳﺨﺘﻠﻒ ﺗﻤﺎﻣًـﺎ ﻋﻦ اﻟﱰﻛﻴﺒﺔ اﻟﺘﻲ ﻧﺮاﻫـ ﺎ ﰲ اﻷﻗـﺮاصﺣـﻮل اﻟﻨﺠﻮم اﻟﺸﻤﺴﻴﺔ ﺣﻴـﺚ ﺗﻬـﻴﻤﻦ اﻟﺠﺰﻳ ﺌـﺎت اﻟﺤﺎﻣﻠﺔ ﻟﻸﻛﺴﺠ ﻣ ﺜﻞ ا ﺎء وﺛـﺎﻧﻲ أﻛﺴـﻴﺪ اﻟﻜﺮﺑﻮن " ﻳﺜﺒﺖ ﻫـﺬا اﻟ و ﺠـﺮم أن ﻫـﺬه ﻓﺌـﺔ ﻓﺮﻳﺪة ﻣﻦ اﻷ ." ﺟﺮام وأﺿﺎﻓﺖ ﻋﻀﻮ اﻟﻔﺮﻳﻖ أﻧﻴـﻴﺲ ﺑـ ﻳﻦ ﻣـﻦ ا ﺮﻛﺰ اﻟﻮﻃﻨﻲ ﻟﻠﺒﺤﺚ اﻟﻌﻠﻤﻲ ﰲ ﻓﺮﻧﺴﺎ " : إﻧﻪ أﻣﺮ ﻻ ﻳﺼﺪق أن ﻧﺘﻤﻜﻦ ﻣﻦ اﻛﺘﺸﺎف وﻗﻴﺎ س ﻛﻤﻴﺔ اﻟﺠﺰﻳﺌـﺎت اﻟﺘـﻲ ﻧﻌﺮﻓﻬـﺎ ﺟﻴـﺪ اً ﻋـﲆ اﻷرض، ﻣﺜﻞ اﻟﺒﻨﺰﻳﻦ، ﰲ ﺟﺴﻢ ﻳﺒﻌﺪ أﻛﺜﺮ ﻣﻦ 600 ". ﺳﻨﺔ ﺿﻮﺋﻴﺔ ﺑﻌﺪ ذﻟـﻚ ﻳﻌﺘـﺰم اﻟﻔﺮﻳـﻖ ﺗﻮﺳـﻴﻊ دراﺳـﺘﻪ اﻟﻌﻠﻤﻴﺔ ﻟﺘﺸﻤﻞ ﻋﻴﻨﺔ أﻛﱪ ﻣﻦ ﻫﺬه اﻷﻗﺮاص ﺣﻮ ل اﻟﻨﺠـﻮم ذات اﻟﻜﺘﻠـﺔ ا ﻨﺨﻔﻀـﺔ ﺟـﺪ اً ﻟﺘﻄﻮﻳﺮ ﻓﻬﻤﻬﻢ ﺪى ﺷﻴﻮع أو ﻏﺮاﺑﺔ ﻣﻨﺎﻃﻖ ﺗﻜﻮﻳﻦ اﻟﻜﻮاﻛﺐ اﻷرﺿﻴﺔ اﻟﻐﻨﻴﺔ ﺑﺎﻟﻜﺮﺑﻮن . وأوﺿـﺢ ﺗﻮﻣـﺎس ﻫﻴﻨﻴـﻨﺞ ﻋﻀـﻮ اﻟﻔﺮﻳـﻖ اﻟﻌﻠﻤﻲ واﻟﺒﺎﺣﺚ اﻟﺮﺋﻴﴘﰲ ﺑﺮﻧـﺎﻣﺞ ﻣﺴـﺢ اﻟﻘﺮص ﺑﺎﻷﺷﻌﺔ ﺗﺤﺖ اﻟﺤﻤـﺮاء ا ﺘﻮﺳـﻄﺔ ) MINDS ( ﻣﻦ ﻣﻌﻬﺪ ﻣﺎﻛﺲ ﺑﻼﻧﻚ ﻟﻌﻠﻢ اﻟﻔﻠﻚ : " ﰲ أ ﺎﻧﻴﺎ إن اﻟﺘﻮﺳﻊ ﰲ دراﺳـﺘﻨﺎ ﺳﻴﺴـﻤﺢ ﻟﻨﺎ ﻛﺬﻟﻚ ﺑﻔﻬﻢ أﻓﻀﻞ ﻟﻜﻴﻔﻴﺔ واﻟﻴـﺔ ﺗﺸـﻜﻞ ﻫﺬه اﻟﺠﺰﻳﺌﺎت ." إن اﻟﻌﺪﻳﺪ ﻣﻦ ا ﻴـﺰات ﰲ ﺑﻴﺎﻧـﺎت ﺗﻠﺴـﻜﻮب وﻳﺐ ﻻ ﺗﺰال ﻏ ﻣﺤﺪدة أﻳﻀـﺎ ﻟـﺬﻟﻚ ﻫﻨـﺎك ﺣﺎﺟﺔ إﱃ ﻣﺰﻳﺪ ﻣﻦ اﻟﺘﺤﻠﻴﻞ اﻟﻄﻴﻔﻲ ﻟﺘﻔﺴ أرﺻﺎدﻧﺎ ﺑﺸﻜﻞ ﻛﺎﻣﻞ ". ﻳﱪز ﻫﺬا اﻟﻌﻤﻞ أﻳﻀ ﺎً ﻋﲆ اﻟﺤﺎﺟﺔ ا ﺎﺳـﺔ إﱃ ﺗﻌﺎون اﻟﻌﻠﻤﺎء ﻋﱪ اﻟﻌﺪﻳﺪ ﻣﻦ اﻟﺘﺨﺼﺼـﺎت اﻟﻌﻠﻤﻴﺔ ا ﺨﺘﻠﻔﺔ . ﻳﺨﺘﺘﻢ اﻟﻔﺮﻳـﻖ اﻟﻌﻠﻤـﻲ ﺑـ ﺄن ﻫـﺬه اﻟﻨﺘـﺎﺋﺞ اﻟﺠﺪﻳﺪة اﻟﺘﻲ ﺗﻢ اﻟﺤﺼﻮل ﻋﻠﻴﻬـﺎ واﻟﺒﻴﺎﻧـﺎت ا ﺼﺎﺣﺒﺔ ﻳﻤﻜﻦ أن ﺗﺴﺎﻫﻢ ﺑﺸـﻜﻞ ﻛﺒـ ﰲ ﻣﺠﺎﻻت أﺧﺮى ﺑﻤﺎ ﰲ ذﻟﻚ اﻟﻔﻴﺰﻳﺎء اﻟﻨﻈﺮﻳـﺔ واﻟﻜﻴﻤﻴــﺎء واﻟﻜﻴﻤﻴــﺎء اﻟﻔﻠﻜﻴــﺔ ﻟﺘﻔﺴــ اﻷﻃﻴـﺎف واﺳﺘﻜﺸـﺎف ا ﻴـﺰات اﻟﺠﺪﻳـﺪة ﰲ ﻧﻄﺎق اﻟﻄﻮل ا ﻮﺟﻲ ﻫﺬا .