Context. (44) Nysa is one of the largest known E-type asteroids. Light curve inversion models have indicated that it may have an elongated shape commonly found in large binary systems. Aims. We aimed to identify the morphology and presence of possible satellites orbiting Nysa. Methods. We observed Nysa with the visible-wavelengths adaptive-optics instruments SHARK-VIS and SPHERE/ZIMPOL in order to image the object with the highest possible spatial resolution, and visually identified surface features on the object. A shape model was constructed from these images and photometric light curves using the ADAM code. Results. Imaging revealed a highly unusual morphology with multiple distinct surface features, including two distinct valleys most easily interpreted as colli. A faint satellite was identified in the deconvolution residuals in multiple datasets. Conclusions. We determine that (44) Nysa is a binary system most likely consisting of a contact-trinary or highly-irregular, coherent primary object and a small satellite.

We describe a pilot study to explore a new generation of fast and low noise CMOS image sensors for time domain astronomy, using two remote telescopes with a baseline of 1635 km. The experiment involves direct imaging with novel qCMOS image sensor technology that combines fast readout with sub-electron readout noise. Moreover, synchronized observations from two remote telescope sites will be used to explore new approaches for measuring Solar System bodies, precision stellar photometry, and speckle imaging. A fast-track installation of an ORCA-Quest2 camera at the Calar Alto Observatory 1.23m telescope has demonstrated the potential of the qCMOS technology for time domain astronomy. Numerical simulations suggest that owing to sub-electron readout noise, qCMOS sensors outperform classical CCDs for high-cadence imaging on 1m-class telescopes. The small penalty for post-readout binning, that is almost insignificant in comparison to higher readout noise detectors, opens interesting applications for scene-dependent data processing in direct imaging, and potentially even for spectroscopy.

High spatial resolution images of the volcanic moon Io at visible and near-infrared wavelengths were obtained by the SHARK-VIS and SHARK-NIR instruments on the Large Binocular Telescope on UT 2025 February 18 and 23. Large-scale changes on Io’s surface are identified in these data and provide vital context for infrared observations from other telescopes and spacecraft. SHARK-VIS imaged part of the plume deposit from a large eruption close to Io’s south pole at Illyrikon that was first observed by NASA’s Juno spacecraft in 2024 December, detecting significant deposit modification. Examples of other significant surface changes detected include at Seth, identifying a new pyroclastic deposit in addition to the new lava flows previously detected in Juno infrared observations; at Amirani, confirming that volcanic activity was now confined to the southern half of the Galileo-epoch lava flow field; new red sulphur-rich deposits at Mixcoatl; and changes in the plume deposits around Prometheus. Plume deposits at Prometheus and at other volcanoes show evidence of complex interplay between different plumes issuing from the same volcano. The combination of SHARK-VIS and Juno JunoCam data moves closer to near-global, near-contemporaneous, visible-wavelength coverage of Io. SHARK-VIS lives up to its promise of a new era of planetary imaging at visible wavelengths and filling the temporal coverage gap between Juno and the arrival of the Europa Clipper and JUICE spacecraft in the Jovian system in 2030 and 2031, respectively.

We report the results from a pilot study to search for black holes and other dark companions in binary systems using direct imaging with SHARK-VIS and the iLocater pathfinder “Lili” on the Large Binocular Telescope. Starting from known single-lined spectroscopic binaries, we select systems with high mass functions that could host dark companions and whose spectroscopic orbits indicate a projected orbital separation ≥30 mas. For this first exploration, we selected four systems (HD 137909, HD 104438, HD 117044, and HD 176695). In each case, we identify a luminous companion and measure the flux ratio and angular separation. However, two of the systems (HD 104438 and HD 176695) are not consistent with simple binary systems and are most likely hierarchical triples. The observed companions rule out a massive compact object for HD 137909, HD 117044, and HD 176695. HD 104438 requires further study because the identified star cannot be responsible for the RV orbit and is likely a dwarf tertiary companion. The SHARK-VIS observation was taken near pericenter, and a second image near apocenter is needed to discriminate between a closely separated luminous secondary and a compact object. When a luminous companion is found, the combination of the RVs and the single SHARK-VIS observation strongly constrains the orbital inclination and the companion mass. Since a single SHARK-VIS observation has a typical on-source observing time of only ∼10 minutes, this a promising method to efficiently identify non-interacting compact object candidates.

The Large Binocular Telescope (LBT) ([1]) Observatory pioneered Adaptive Optics (AO) technologies such as Adaptive Secondary Mirror (ASM)([2]), Pyramid wavefront sensor([3]), and Ground-layer AO using Rayleigh lasers([4]) at 8-10 m class telescopes. We have initiated an effort to turn LBT AO into a facility-class capability. The effort involves (1) building an AO team with AO development capability, (2) improving the robustness of the AO, (3) developing in-house AO expertise to maintain and troubleshoot the AO systems, (4) automating processes for efficient on-sky operation, (5) tracking performance metrics and cultivating accountability for on-sky AO performance, and (6) minimizing the operational risks for the ASMs. We present the status of these developments. LBTO continues its efforts to develop innovative technology. We explore the next phase of AO developments, including Agile Extreme Adaptive Optics (AgXAO) on the DX side of the LINC-NIRVANA([5][6]) optical bench to overcome the limitation imposed by varying and large atmospheric seeing at Mount Graham. AgXAO implementation includes the development of (1) a high-order, high-sensitivity wavefront sensor, (2) a high-density deformable mirror with 3000 actuators and next-generation ASM with about 950 actuators, (3) active optics integration, (4) vibration and wavefront piston control, (5) atmospheric turbulence measurements and weather forecast integration, and (6) a visible camera and an AO-corrected narrow-field fiber-coupled IFU spectrograph using one of the existing workhorse visible spectrographs. Developing AgXAO on the SX side, too, would enable Fizeau imaging in the visible wavelengths. AgXAO will also serve as a general-purpose high-contrast (and subsequently a Fizeau imaging) Testbed on LBT to test advanced wavefront control algorithms, including astrophotonics experiments, and machine learning algorithms with minimal impact on routine science operations. We propose developing AgXAO through student projects to train the next-generation scientists and engineers for the extremely large telescope (ELT) era. The ultimate goal is to push large aperture ground-based telescopes to their performance limits and make them competitive with space telescopes in terms of PSF stability and performance to enable breakthrough science.

Since volcanic activity was first discovered on Io from Voyager images in 1979, changes on Io's surface have been monitored from both spacecraft and ground-based telescopes. Here, we present the highest spatial resolution images of Io ever obtained from a ground-based telescope. These images, acquired by the SHARK-VIS instrument on the Large Binocular Telescope, show evidence of a major resurfacing event on Io's trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images show that a plume deposit from a powerful eruption at Pillan Patera has covered part of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io's surface using adaptive optics at visible wavelengths.

The Large Binocular Telescope, with its expansive collecting area, angular resolving power, and advanced optical design, provides a robust platform for development and operation of advanced instrumentation for astronomical research. The LBT currently hosts a mature suite of instruments for spectroscopy and imaging at optical through mid-infrared wavelengths, supported by sophisticated adaptive optics systems. This contribution summarizes the current state of instrumentation, including upgrades to existing instruments and commissioning of second generation instruments now in progress. The LBT is soliciting proposals for next generation instrument concepts, with participation open to consortium members and others interested in participation in the Observatory.

A new development in the field of adaptive optics (AO) on ground-based telescopes enables routine monitoring of changes on Io's surface at scales down to ~80km (achieved), or even down to ~50km (in the limit). Our observations, taken with SHARK-VIS on the Large Binocular Telescope (LBT) in Arizona, demonstrate this new capability. SHARK-VIS adds a visible light science channel to the AO system at LBT. While AO science in the infrared has been widespread for decades, visible-light AO science is new. SHARK-VIS, which saw first light at LBT on October 2nd, 2023, is one of only a few visible-light AO instruments on large telescopes.Our images of Io, taken soon after first light, are of the highest spatial resolution ever attained from a ground-based telescope. In addition to confirming known surface features, these images show a previously unseen plume deposit that obscures a portion of Pele's persistent red ring (see Fig. 1). This plume deposit, we believe, came as the result of a powerful eruption at Pillan Patera.Figure 1. The SHARK-VIS detection image on Nov. 23, 2023 (upper left), and again on Jan. 10, 2024 (upper right), and the reprojection of the Voyager and Galileo spacecraft-derived Io photomomosaic for Jan. 10, 2024 (center) (Becker & Geissler, 2005).To determine the date of the Pillan eruption, we analyzed thermal emission data collected by other telescopes over the last four years. Although these infrared images were necessarily taken at lower spatial resolution (due to the wavelengths used), the spatial resolution is sufficient to detect if and when excess thermal emission might have originated from Pillan Patera. These data show a spike in thermal emission, indicating a powerful eruption, during August 2021. Augmented with data from the Juno JIRAM instrument, we believe that this spike corresponds to the eruption responsible for the plume deposit seen in the SHARK-VIS images.These SHARK-VIS images serve as a demonstration of how adaptive optics at visible wavelengths will allow us to monitor surface changes on Io at regular intervals. Note that, prior to the SHARK-VIS observation, the most recent high-resolution imaging of the Pele region was from the New Horizons fly-by during March 2007. By April 2024, as seen by the visible imager on the Juno spacecraft, the red ring around Pele had repaired itself. Without the SHARK-VIS images, this resurfacing event would have never been detected.To date, regular monitoring of Io using ground-based facilities has largely been restricted to M-band (4.8 μm) imaging which, even using adaptive optics on 8-10 metre telescopes, yields spatial resolution of about 400-600 km. While there will always be a need for infrared images of Io for the thermal data that informs volcanology, visible-light images at 50-80km resolution allow us to "see" the landscape, to more accurately locate the effects of eruptions and associated features such as plume deposits.In our presentation, we will provide details of the Pillan plume deposit and its encroachment onto Pele's ring, and how that observation serves as a demonstration of how we will be able to monitor surface changes on Io going forward. We will also describe future ground-based systems that could produce imaging of Io down to spatial scales below 12km.

MICADO is the first-light camera of the ESO ELT, allowing NIR imaging and long-slit spectroscopy assisted by adaptive optics. MICADO is now entering its construction phase, and the software for data reduction is reaching an adequate maturity level. The PSF Reconstruction (PSF-R) of MICADO is a software tool for the blind derivation of the PSF, only using adaptive optics telemetry data. An update of the status of the PSF-R service is provided here. The PSF-R prototype has been tested on ERIS@VLT data in order to check the reconstruction of on- and off-axis PSFs. The on-axis PSF-R is accurate at a few percent level on Strehl, FWHM, Encircled Energy, and half light radius, while for the off-axis case the match is within 10-15% at a distance of half isoplanatic angle. The first version of the workflow for the PSF-R pipeline has been developed and verified using the latest release of the ESO data processing system. A set of simulations has been implemented on the morphological analysis of distant galaxies, showing that the accuracy of the PSF-R matches the goals needed to study their morphology. In summary, the PSF-R team is on the right track towards the ELT first light.

MICADO is a first light instrument for the Extremely Large Telescope (ELT), set to start operating later this decade. It will provide diffraction limited imaging, astrometry, high contrast imaging, and long slit spectroscopy at near-infrared wavelengths. During the initial phase operations, adaptive optics (AO) correction will be provided by its own natural guide star wavefront sensor. In its final configuration, that AO system will be retained and complemented by the laser guide star multi-conjugate adaptive optics module MORFEO (formerly known as MAORY). Among many other things, MICADO will study exoplanets, distant galaxies and stars, and investigate black holes, such as Sagittarius A* at the centre of the Milky Way. After their final design phase, most components of MICADO have moved on to the manufacturing and assembly phase. Here we summarize the final design of the instrument and provide an overview about its current manufacturing status and the timeline. Some lessons learned from the final design review process will be presented in order to help future instrumentation projects to cope with the challenges arising from the substantial differences between projects for 8-10m class telescopes (e.g. ESO-VLT) and the next generation Extremely Large Telescopes (e.g. ESO-ELT). Finally, the expected performance will be discussed in the context of the current landscape of astronomical observatories and instruments. For instance, MICADO will have similar sensitivity as the James Webb Space Telescope (JWST), but with six times the spatial resolution.

The highest scientific return, for adaptive optics (AO) observations, is achieved with a reliable reconstruction of the PSF. This is especially true for MICADO@ELT. In this presentation, we will focus on extending the MICADO PSF reconstruction (PSF-R) method to the off-axis case. Specifically, a novel approach based on temporal-based tomography of AO telemetry data has been recently implemented. Results from the PSF-R of both simulated and real data show that, at half isoplanatic angle distances, a precision of about 10 - 15% is achievable in both Strehl ratio and full-width at half maximum, paving the way to extend the MICADO PSF-R tool also to the multi-conjugated AO case.