Context. While it is conjectured that a chromospheric canopy plays a role in penumbra formation, it has been difficult to find observational evidence of the connectivity between the photosphere and the chromosphere. Aims: We investigate the existence of a chromospheric canopy as a necessary condition for the formation of a penumbra. Another aim is

Context. Quaoar is a classical trans-Neptunian object (TNO) with an area-equivalent diameter of 1100 km and an orbital semi-major axis of 43.3 astronomical units. Based on stellar occultations observed between 2018 and 2021, an inhomogeneous ring (Q1R, i.e., Quaoar's first ring) has been detected around this body. Aims: A new stellar occultation by

K2-136 is a late-K dwarf (0.742 ± 0.039 M ⊙) in the Hyades open cluster with three known, transiting planets and an age of 650 ± 70 Myr. Analyzing K2 photometry, we found that planets K2-136b, c, and d have periods of 8.0, 17.3, and 25.6 days and radii of 1.014 ± 0.050 R ⊕, 3.00 ± 0.13 R ⊕, and 1.565 ± 0.077 R ⊕, respectively. We collected 93

High-velocity stars in the Milky Way are related to extreme astrophysical phenomena. In this work, we characterize 28 stars with Galactocentric velocities higher than 400 $\mathrm{km\, s^{-1}}$ observed in the Javalambre Photometric Local Universe Survey Data Release 2 (J-PLUS DR2) survey. We combine J-PLUS photometry with astrometric data from the

We present observations from X-ray to mid-infrared wavelengths of the most energetic non-quasar transient ever observed, AT2021lwx. Our data show a single optical brightening by a factor >100 to a luminosity of 7 × 10 45 erg s -1 and a total radiated energy of 1.5 × 10 53 erg, both greater than any known optical transient. The decline is smooth and

The correlation between the broad line region radius and continuum luminosity (R-L relation) of active galactic nuclei (AGNs) is critical for single-epoch mass estimates of supermassive black holes (SMBHs). At z ~ 1-2, where AGN activity peaks, the R-L relation is constrained by the reverberation mapping (RM) lags of the Mg II line. We present 25