In a study reported recently, astronomers observed the SN 1987A remnant using Teleskop Angkasa James Webb (JWST). The results showed emission lines of ionized argon and other heavily ionised chemical species from the centre of the nebula around SN 1987A. Observation of such ions means presence of a newly born neutron bintang as the source of high energy radiation at the centre of the supernova remanent.
Bintang are born, age and finally die with an explosion. When the fuel runs out and nuclear fusion in the core of star ceases, the inward gravitational force squeezes the core to contract and collapse. As the collapse begins, in few milliseconds, the core gets so compressed that electrons and protons combine to form neutrons and a neutrino is released for each neutron formed. In the case of bintang supermasif,teras runtuh dalam jangka masa yang singkat dengan letupan yang kuat dan bercahaya dipanggil supernova. The burst of neutrinos produced during core-collapse escape into outer ruang unimpeded due to its non-interactive nature with matter, ahead of photons which are trapped in the field, and acts as a beacon or an early warning of a possible optical observation of supernova explosion soon
SN 1987A was the last supernova event seen in southern sky in February 1987. It was the first such supernova event visible to the naked eye since Kepler’s in 1604. Located 160 000 light-years from Earth in the nearby Large Magellanic Cloud (a satellite galaksi of the Milky Way), it was one of the brightest exploding stars seen in more than 400 years that blazed with the power of 100 million suns for several months and provided unique opportunity to study the phases before, during, and after the death of a bintang.
The SN 1987A was a core-collapse supernova. The explosion was accompanied by neutrino emission which was detected by two water Cherenkov detectors, Kamiokande-II and the Irvine-MichiganBrookhaven (IMB) experiment about two hours prior to the optical observation. This suggested that a compact object (a neutron star or lubang hitam) should have formed after core collapse, but no neutron star following SN 1987A event or any other such recent supernova explosion was ever directly detected. Though, there is indirect evidence for presence of a neutron star in the remanent.
In a study reported recently, astronomers observed the SN 1987A remnant using Teleskop Angkasa James Webb (JWST). The results showed emission lines of ionized argon and other heavily ionised chemical species from the centre of the nebula around SN 1987A. Observation of such ions means presence of a newly born neutron star as the source of high energy radiation at the centre of the supernova remanent.
Ini adalah kali pertama kesan pelepasan tenaga tinggi daripada bintang neutron muda telah dikesan.
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Sumber:
- Fransson C., et al 2024. Garis pelepasan akibat sinaran mengion daripada objek padat dalam sisa Supernova 1987A. SAINS. 22 Februari 2024. Jld 383, Keluaran 6685 ms 898-903. DOI: https://doi.org/10.1126/science.adj5796
- Universiti Stockholm. Berita - Teleskop James Webb mengesan kesan bintang neutron dalam supernova ikonik. 22 Februari 2024. Boleh didapati di https://www.su.se/english/news/james-webb-telescope-detects-traces-of-neutron-star-in-iconic-supernova-1.716820
- ESA. News-Webb menemui bukti untuk bintang neutron di tengah-tengah sisa supernova muda. Boleh didapati di https://esawebb.org/news/weic2404/?lang
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