An extreme ultraviolet(EUV) close-up view of the Sun offers unprecedented detail of heating events in the solar corona. Enhanced temporal and spatial images obtained by the Solar Orbiter during its first science perih...An extreme ultraviolet(EUV) close-up view of the Sun offers unprecedented detail of heating events in the solar corona. Enhanced temporal and spatial images obtained by the Solar Orbiter during its first science perihelion enabled us to identify clustered EUV bright tadpoles(CEBTs) occurring near the footpoints of coronal loops.Combining SDO/AIA observations, we determine the altitudes of six distinct CEBTs by stereoscopy, ranging from ~1300 to 3300 km. We then notice a substantial presence of dark, cooler filamentary structures seemingly beneath the CEBTs, displaying periodic up-and-down motions lasting 3–5 minutes. This periodic behavior suggests an association of the majority of CEBTs with Type I spicules. Out of the ten selected CEBTs with fast downward velocity, six exhibit corrected velocities close to or exceeding 50 km s^(-1). These velocities notably surpass the typical speeds of Type I spicules. We explore the generation of such velocities. It indicates that due to the previous limited observations of spicules in the EUV wavelengths, they may reveal novel observational features beyond our current understanding. Gaining insights into these features contributes to a better comprehension of small-scale coronal heating dynamics.展开更多
基金supported by National Key R&D Program of China Nos. 2022YFF0503800 and 2021YFA0718600the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB0560000)+1 种基金National Natural Science Foundation of China (NSFC, Grant Nos. 12073032, 42274201, 42150105, and 42204176)the Specialized Research Fund for State Key Laboratories of China。
文摘An extreme ultraviolet(EUV) close-up view of the Sun offers unprecedented detail of heating events in the solar corona. Enhanced temporal and spatial images obtained by the Solar Orbiter during its first science perihelion enabled us to identify clustered EUV bright tadpoles(CEBTs) occurring near the footpoints of coronal loops.Combining SDO/AIA observations, we determine the altitudes of six distinct CEBTs by stereoscopy, ranging from ~1300 to 3300 km. We then notice a substantial presence of dark, cooler filamentary structures seemingly beneath the CEBTs, displaying periodic up-and-down motions lasting 3–5 minutes. This periodic behavior suggests an association of the majority of CEBTs with Type I spicules. Out of the ten selected CEBTs with fast downward velocity, six exhibit corrected velocities close to or exceeding 50 km s^(-1). These velocities notably surpass the typical speeds of Type I spicules. We explore the generation of such velocities. It indicates that due to the previous limited observations of spicules in the EUV wavelengths, they may reveal novel observational features beyond our current understanding. Gaining insights into these features contributes to a better comprehension of small-scale coronal heating dynamics.