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1. A Massive Black Hole 0.8 kpc from the Host Nucleus Revealed by the Offset Tidal Disruption Event AT2024tvd

   https://doi.org/10.3847/2041-8213/add7de  

   Yao, Yuhan; Chornock, Ryan; Ward, Charlotte; Hammerstein, Erica; Sfaradi, Itai; Margutti, Raffaella; Kelley, Luke Zoltan; Lu, Wenbin; Liu, Chang; Wise, Jacob; et al (May 2025, The Astrophysical Journal Letters)

   Abstract Tidal disruption events (TDEs) that are spatially offset from the nuclei of their host galaxies offer a new probe of massive black hole (MBH) wanderers, binaries, triples, and recoiling MBHs. Here we present AT2024tvd, the first off-nuclear TDE identified through optical sky surveys. High-resolution imaging with the Hubble Space Telescope shows that AT2024tvd is 0 $\stackrel{\text{″}}{.}$ 914 ± 0 $\stackrel{\text{″}}{.}$ 010 offset from the apparent center of its host galaxy, corresponding to a projected distance of 0.808 ± 0.009 kpc atz= 0.045. Chandra and Very Large Array observations support the same conclusion for the TDE’s X-ray and radio emission. AT2024tvd exhibits typical properties of nuclear TDEs, including a persistent hot UV/optical component that peaks atL_bb ∼ 6 × 10⁴³erg s⁻¹, broad hydrogen lines in its optical spectra, and delayed brightening of luminous (L_X,peak ∼ 3 × 10⁴³erg s⁻¹), highly variable soft X-ray emission. The MBH mass of AT2024tvd is 10^6±1M_⊙, at least 10 times lower than its host galaxy’s central black hole mass (≳10⁸M_⊙). The MBH in AT2024tvd has two possible origins: a wandering MBH from the lower-mass galaxy in a minor merger during the dynamical friction phase or a recoiling MBH ejected by triple interactions. Combining AT2024tvd with two previously known off-nuclear TDEs discovered in X-rays (3XMM J2150 and EP240222a), which likely involve intermediate-mass black holes in satellite galaxies, we find that the parent galaxies of all three events are very massive (∼10^10.9M_⊙). This result aligns with expectations from cosmological simulations that the number of offset MBHs scales linearly with the host halo mass. 

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2. VLA Observations Confirm AT 2023mfm as an Off-nuclear Tidal Disruption Event

   https://doi.org/10.3847/2515-5172/ae7a6a  

   Li, Wenkai; Christy, Collin T; Alexander, Kate D; Sfaradi, Itai; Huang, Xinya; Jiang, Ning; Laskar, Tanmoy; Mummery, Andrew; Franz, Noah; Goodwin, Adelle J; et al (June 2026, Research Notes of the AAS)

   Abstract We report new radio observations of the tidal disruption event (TDE) AT 2023mfm, which we identified as a high-confidence candidate in a systematic search for off-nuclear TDEs. High-resolution NSF Karl G. Jansky Very Large ArrayC-band (6 GHz) imaging resolves two radio sources: one consistent with the host-galaxy nucleus and one offset by $0\stackrel{″}{.}651\pm 0\stackrel{″}{.}036$ (1.06  ±  0.06 kpc), consistent with the Zwicky Transient Facility and Pan-STARRS1 positions of AT 2023mfm. These observations confirm the off-nuclear nature of AT 2023mfm, demonstrating the power of high-resolution radio imaging to validate off-nuclear TDE candidates and reveal hidden off-nuclear massive black holes. 

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3. Molecular Outflows in the Nucleus of the Nearby Compton-thick AGN NGC 3079

   https://doi.org/10.3847/1538-4357/ae6654  

   Lin, Ming-Yi; Medling, Anne M; Davies, Richard I; Krips, Melanie; Barcos-Muñoz, L; Genzel, R; González-Alfonso, E; Gracia-Carpio, J; Lutz, D; Neri, R; et al (June 2026, The Astrophysical Journal)

   Abstract We present Northern Extended Millimeter Array observations of the CO (2–1) molecular gas kinematics in the nearby Compton-thick Seyfert 2 galaxy NGC 3079, with an angular resolution of 0 $\stackrel{\text{″}}{.}$ 5 (∼40 pc). To interpret the observed CO (2–1) kinematics, we model the rotating disk using two software tools, 3D-Barolo and DysmalPy, to generate mock 3D data cubes. Both models indicate, in addition to the rotating disk, the presence of a spatially unresolved nuclear component characterized by high velocity dispersion. Analysis of the visibility data reveals that the blueshifted, high-velocity component is spatially offset from the continuum peak by 0 $\stackrel{\text{″}}{.}$ 17 (∼14 pc) and exhibits line-of-sight velocities ofv−v_sys= −350 to −450 km s⁻¹, which we interpret as a nuclear molecular outflow. We calculate a molecular gas mass outflow rate of 8.82M_⊙yr⁻¹, with a kinetic power ( ${\dot{E}}_{\text{out}}$ ) of 3.8 ×10⁴¹erg s⁻¹and a momentum rate ( ${\dot{p}}_{\text{out}}$ ) of 2.05 × 10³⁴Dyne. The momentum rate exceeds the AGN radiation momentum rate by a factor of ∼15, suggesting an energy-driven outflow. Furthermore, we argue that the derived kinetic power of the nuclear molecular outflow favors a jet-powered scenario that explains the slowdown and brightening of the parsec-scale radio source observed with the Very Long Baseline Array. 

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4. Inside the Stagnation Radius of the Nearest Billion-solar-mass Black Hole

   https://doi.org/10.3847/1538-4357/adfa93  

   Wrobel, J M; Pesce, D W; Nyland, K E (September 2025, The Astrophysical Journal)

   Abstract We used the NSF Jansky Very Large Array at a frequencyν = 22 GHz to study the nearest billion-solar-mass black hole (BH), in the early-type galaxy NGC 3115 at a distance of 9.7 Mpc. We localize a faint continuum nucleus, with flux densityS_{22 GHz} = 48.2 ± 6.4μJy, to a FWHM diameterd_{22 GHz} < 59 mas (2.8 pc). We find no evidence for adjacent emission within a stagnation region of radiusR_sta ∼ 360 mas (17 pc) identified in a recent hydrodynamic simulation tailored to NGC 3115. Within that region, the simulated gas flow developed into an advection-dominated accretion flow (ADAF). The nucleus’ luminosity densityL_{22 GHz} = 5.4 × 10¹⁷W Hz⁻¹is about 60 times that of Sagittarius A^⋆. The nucleus’ spectral index ${\alpha }_{10\mathrm{GHz}}^{22\mathrm{GHz}}=-1.85\pm 0.18$ (S_ν ∝ ν^α) indicates optically thin synchrotron emission. The spectral energy distribution of the nucleus peaks nearν_peak = 9 GHz. Modeling this radio peak as an ADAF implies a BH massM_ADAF = (1.2 ± 0.2) × 10⁹M_⊙, consistent with previous estimates of (1–2) × 10⁹M_⊙from stellar or hot-gas dynamics. Also, the Eddington-scaled accretion rate for NGC 3115, ${\dot{M}}_{\mathrm{ADAF}}/{\dot{M}}_{\mathrm{Edd}}=1.2_{-0.6}^{+1.0}\times 10^{-8}$ , is about 4–8 times lower than recent estimates for Sagittarius A^⋆. 

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5. Discovery of H α Emission from a Protoplanet Candidate around the Young Star 2MASS J16120668–3010270 with MagAO-X

   https://doi.org/10.3847/2041-8213/adfcbd  

   Li_李, Jialin 嘉霖; Close, Laird M; Long_龙, Feng 凤; Males, Jared R; Haffert, Sebastiaan Y; Weinberger, Alycia; Follette, Katherine; Andrews, Sean; Carpenter, John; Foster, Warren B; et al (September 2025, The Astrophysical Journal Letters)

   Abstract 2MASS J16120668–3010270 (hereafter 2MJ1612) is a young M0 star that hosts a protoplanetary disk in the Upper Scorpius star-forming region. Recent Atacama Large Millimeter/submillimeter Array (ALMA) observations of 2MJ1612 show a mildly inclined disk (i = 37°) with a large dust-depleted gap (R_cav ≈ 0 $\stackrel{\text{″}}{.}$ 4 or 53 au). We present high-contrast Hαobservations from MagAO-X on the 6.5 m Magellan telescope and new high-resolution submillimeter dust continuum observations with ALMA of 2MJ1612. On both 2025 April 13 and 16, we recovered a point source with Hαexcess with a signal-to-noise ratio ≳5 within the disk gap in our MagAO-X angular and spectral differential images at a separation of 141.96 ± 2.10 mas (23.45 ± 0.29 au deprojected) from the star and a position angle ​​​​​of 159 $\stackrel{\text{°}}{.}$ 00 ± 0 $\stackrel{\text{°}}{.}$ 55. Furthermore, this Hαsource is within close proximity to aK-band point source in the SPHERE/IRDIS observation taken on 2023 July 21. The astrometric offset between theKband and Hαsource can be explained by orbital motion of a bound companion. Thus, our observations can be best explained by the discovery of an accreting protoplanet, 2MJ1612 b, with an estimated mass of 4M_Jupand a Hαline flux ranging from (29.7 ± 7.5) × 10⁻¹⁶erg s cm²to (8.2 ± 3.4) × 10⁻¹⁶erg s cm². 2MJ1612 b is likely the third example of an accreting Hαprotoplanet responsible for carving the gap in its host disk, joining PDS 70 b and c. Further study is necessary to confirm and characterize this protoplanet candidate and to identify any additional protoplanets that may also play a role in shaping the gap. 

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