Category: Astronomy

ENG: Epsilon Indi, a dwarf star observed by an international research team, including the Institute of Astrophysics and Space Sciences in Portugal and the University of Birmingham, has displayed solar-like oscillations, commonly known as starquakes. These oscillations are crucial for understanding the internal composition of stars, similar to how earthquakes provide insight into Earth’s interior.

The detection of these oscillations was achieved through asteroseismology, a method that examines the vibrations within stars, by utilizing the ESPRESSO spectrograph on the Very Large Telescope at the European Southern Observatory. This technique allowed the team to observe the quakes with exceptional precision, highlighting the technological advancements in the field. Lead researcher Tiago Campante from the Institute of Astrophysics and Space Sciences at the University of Porto emphasized the importance of this achievement, noting that it demonstrates the feasibility of precise asteroseismology for studying cool dwarf stars with surface temperatures significantly lower than the Sun’s.

The implications of this discovery extend beyond the academic curiosity of stellar interiors. Orange dwarf stars, like Epsilon Indi, are of particular interest in the quest for habitable planets and extraterrestrial life. The observed discrepancies between predicted and actual sizes of these stars could impact the accuracy of detecting exoplanets using the transit method. By refining our understanding of star sizes through the detection of oscillations, astronomers can improve theoretical models of stars and the search for planets around them. This breakthrough also paves the way for the European Space Agency’s PLATO Mission, scheduled for launch in 2026, which aims to explore oscillations in a broader range of orange dwarfs and search for planets orbiting these stars.

RO: Epsilon Indi, o stea pitică observată de o echipă internațională de cercetare, formată din Institutul de Astrofizică și Științe Spațiale din Portugalia și Universitatea din Birmingham, a afișat oscilații similare soarelui, cunoscute sub numele de starquakes (cutremure stelare). Aceste oscilații sunt esențiale pentru înțelegerea compoziției interne a stelelor, într-un mod similar cu cel în care cutremurele oferă informații despre interiorul Pământului.

Detectarea acestor oscilații a fost realizată prin asteroseismologie, o metodă care examinează vibrațiile din interiorul stelelor, utilizând spectrograful ESPRESSO de pe Very Large Telescope (Telescopul Foarte Mare) al Observatorului European de Sud. Această tehnică a permis echipei să observe cutremurele cu o precizie excepțională, evidențiind progresele tehnologice din domeniu. Cercetătorul principal Tiago Campante de la Institutul de Astrofizică și Științe Spațiale de la Universitatea din Porto a subliniat importanța acestei realizări, notând că demonstrează fezabilitatea asteroseismologiei precise pentru studiul stelelor pitice răcoroase cu temperaturi ale suprafeței semnificativ mai scăzute decât cele ale Soarelui.

Implicațiile acestei descoperiri se extind dincolo de curiozitatea academică privind interioarele stelare. Stelele pitice portocalii, precum Epsilon Indi, sunt de interes particular în căutarea planetelor locuibile și a vieții extraterestre. Discrepanțele observate între dimensiunile prezise și cele reale ale acestor stele ar putea afecta acuratețea detectării exoplanetelor folosind metoda de tranzit. Prin rafinarea înțelegerii noastre despre dimensiunile stelelor prin detectarea oscilațiilor, astronomii pot îmbunătăți modelele teoretice ale stelelor și căutarea planetelor în jurul acestora. Această descoperire deschide, de asemenea, calea pentru Misiunea PLATO a Agenției Spațiale Europene, programată pentru lansare în 2026, care vizează explorarea oscilațiilor într-o gamă mai largă de pitici portocalii și căutarea planetelor care orbitează aceste stele.

Source (University of Birminham, “Tiniest ‘starquake’ ever detectedSource (University of Birminham”, 25.03.2024)

Paper: Campante, T.L., Kjeldsen, H., Li, Y., Lund, M.N., Silva, A.M., Corsaro, E., da Silva, J.G., Martins, J.H.C., Adibekyan, V., Silva, T.A. and Bedding, T.R., 2024. Expanding the frontiers of cool-dwarf asteroseismology with ESPRESSO-Detection of solar-like oscillations in the K5 dwarf ϵ Indi. Astronomy & Astrophysics, 683, p.L16.

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