Borissova, JuraJuraBorissovaGuo, ZhenZhenGuoKurtev, RadostinRadostinKurtevP. W. LucasVardan ElbakyanC. S. MorrisA. BayoL. J. SmithA. Caratti o GarattiCarlos Contreras PeñaD. MinnitiJessy JoseMizna AshrafJ. Alonso-GarcíaN. MillerH D S Muthu2025-08-252025-08-252023-12-2710.1093/mnrasl/slad2012-s2.0-85184221427https://cris-uv-2.scimago.es/handle/123456789/6290WOS:001594540600009ABSTRACT During the pre-main-sequence evolution, Young Stellar Objects (YSOs) assemble most of their mass during the episodic accretion process. The rarely seen FUOr-type events are valuable laboratories to investigate the outbursting nature of YSOs. Here, we present multiwavelength detection of a high-amplitude eruptive source in the young open cluster VdBH 221 with an ongoing outburst, including optical to mid-infrared time series and near-infrared spectra. The initial outburst has an exceptional amplitude of >6.3 mag in Gaia and 4.6 mag in Ks, with a peak luminosity up to 16 L⊙ and a peak mass accretion rate of 1.4 × 10−5 M⊙ yr−1. The optical to infrared spectral energy distribution of this object is consistent with a low-mass star (0.2 M⊙) with a modest extinction (AV < 2 mag). A 100-d delay between optical and infrared rising stages is detected, suggesting an outside-in origin of the instability. The spectroscopic features of this object reveal a self-luminous accretion disc, very similar to FU Orionis, with a low line-of-sight extinction. Most recently, there has been a gradual increase in brightness throughout the wavelength range, possibly suggesting an enhancement of the mass accretion rate.enacceso abiertoAstronomy And AstrophysicsSpace And Planetary Sciencearticle