We report on recent results from our successful and pioneering observational program with ALMA to study emerging ultracompact HII regions of pre-planetary nebulae (pPNe) using mm-wavelength recombination lines (mRRLs) as new optimal tracers. We focus on our study of two poster-child pPNe, namely, M 2-9 and CRL 618. We reveal the structure and kinematics of the enigmatic inner nebular regions of these objects with an unprecedented angular resolution down to 20-30 mas (∼15-30 AU linear scales). For both targets, the ionized central regions are elongated along the main symmetry axis of the large-scale nebulae, consistent with bipolar winds, and show notable axial velocity gradients with expansion velocities of up to ∼100 kms. The intensity and width of the H30α profiles are found to be time variable, denoting changes on scales of a few years of the physical properties and kinematics of the present-day post-AGB ejections. Our ongoing analysis involves 3D, non-LTE radiative transfer modeling of the mRRLs and free-free continuum emission. This approach allows us to provide an exceptionally detailed description of the physical conditions in the innermost layers of these well known pPNe.

In this article, the physical processes occurring in the convective layer and the photosphere of the Sun and their connection to the formation of active regions (ARs) and the development of the corresponding magnetic field are explored. Specifically, we test the magnetic flux emergence hypothesis and based on the line-of-sight magnetic field and Doppler shift data obtained from the Global Oscillation Network Group (GONG) observations. The study encompasses the analysis of 24 ARs observed during the period from 2011 to 2022. We find a strong correlation between the magnetic flux and the imbalance of radial velocity fluxes. The results indicate that the magnetic flux emergence hypothesis cannot fully explain the evolution of ARs during their early stages of development.

The Planetary Nebula H 2-18 is analysed with the full-3D capabilities of the MOCASSIN code. The collected HST images help to constrain the density distribution while the ARGUS 2D spectroscopy provides a new and unique information on kinematics.

We use the rotation curve from Gaia data release (DR) 3 to estimate the mass of the Milky Way. We consider an Einasto density profile to model the dark matter component. We extrapolate and obtain a dynamical mass at 112 kpc. This lower-mass Milky Way is consistent with the significant declining rotation curve, and can provide new insights into our Galaxy and halo inhabitants.

Historical sunspot records provide piece by piece more information on solar variability on a centennial scale. In this work, we analyze sunspot observations from the archives of Georg Christoph Eimmart, which is the second-richest data set of the Maunder minimum after the archives of the Paris observatory. Comparing the dates of the blank solar disk from the database by Hoyt & Schatten (1998) with dates of observations at the Eimmart observatory, we find that spotless days reports originate from astrometric observations. A comparison of the observations by La Hire and Müller of 1719 suggests that the observations by La Hire were for astrometric purposes as well, rather than aimed at sunspot counting.

During the last decade, our understanding of stellar physics and evolution has undergone a tremendous revolution thanks to asteroseismology. Space missions such as CoRoT, Kepler, K2, and TESS have already been observing millions of stars providing high-precision photometric data. With these data, it is possible to study the convection of stars through the convective background in the power spectrum density of the light curves. The properties of the convective background or granulation has been shown to be correlated to the surface gravity of the stars. In addition, when we have enough resolution (so long enough observations) and a high signal-to-noise ratio (SNR), the individual modes can be characterized in particular to study the internal rotational splittings and magnetic field of stars. Finally, the surface magnetic activity also impacts the amplitude and hence detection of the acoustic modes. This effect can be seen as a double-edged sword. Indeed, modes can be studied to look for magnetic activity changes. However, this also means that for stars too magnetically active, modes can be suppressed, preventing us from detecting them.

In this talk, I will present some highlights on what asteroseismology has allowed us to better understand the convection, rotation, and magnetism of solar-like stars while opening doors to many more questions.

The Small Magellanic Cloud (SMC), as one of the nearest galaxies to us, provides a superb laboratory for studying resolved stars in exquisite detail. We present here the largest sample of SMC Red Giant Branch (RGB) stars (∼6000) observed with the AAOmega spectrograph fed by the Two Degree Field (2dF) multi-object system at the Anglo-Australian Telescope of the Siding Spring Observatory (Australia). Metallicities were recovered using a direct estimation of [Fe/H] from the equivalent widths of the Calcium triplet (CaT). We discuss the potential implications of the metallicity gradients and compare them with previous determinations of star formation history to assess the consequences of encounters between the SMC and the Large Magellanic Cloud.

The formation of highly structured, spatially localized complex structures during solar flux emergence facilitates adaptation of topological methods, extending the research of emerging macroscopic MHD fluxes into knots, links and braids. Combining mathematical considerations, remote images and in situ satellite observations at solar vicinity, we construct new characteristics of those braided/knotted magnetic structures, applying Braid and Knot Theory to physical configurations, deducing their topological invariants, constraining the evolution and stability while delineating the relaxation path to magnetized equilibria.

The fast rotating solar analogs show a decrease of the dynamo period with an increase of the rotation rate for the moderate stellar rotation periods in the range between 10 and 25 days. Simultaneously, observations indicate two branches: the “in-active” branch stars shows short dynamo cycles and the active branch stars show the relatively long magnetic cycles. We suggest that this phenomenon can be produced by effect of the doubling frequency of the dynamo waves, which is due to excitation of the second harmonic. It is generated because of the nonlinear B2 effects in the large-scale dynamo.

The Planetary Nebula Luminosity Function (PNLF) remains an important extragalactic distance indicator despite a still limited understanding of its most important feature - the bright cut-off. External galaxies benefit from consistent distance and extinction, which makes determining the PNLF easier but detailed study of individual objects much more difficult. Now, the advent of parallaxes from the Gaia mission has dramatically improved distance estimates to planetary nebulae (PNe) in the Milky Way. We have acquired ground-based narrowband imagery and measured the [OIII] fluxes for a volume-limited sample of hundreds of PNe whose best distance estimates from Gaia parallaxes and statistical methods place them within 3 kpc of the Sun. We present the first results of our study, comparing the local PNLF to other galaxies with different formation histories, and discussing how the brightness of the PNe relates to the evolutionary state of their central stars and the properties of the nebula.

I present a short overview of the COST Action NanoSpace (“Carbon molecular nanostructures in space”; CA21126) together with the most recent updates. This includes the main motivation and scientific challenges, Action structure and organization (e.g., working groups, tasks, etc.) as well as the main objectives and deliverables. A special emphasis is given to the interdisciplinary approach proposed to attack the Action challenge and the main needs to drive the field forward. Planetary nebulae (PNe) are wonderful astrochemistry laboratories and a dominant source of complex carbon molecular nanostructures (i.e., nanocarbons) in space, being key astronomical objects for NanoSpace. The main goal is to show the power of networking as a tool to understand nanocarbons in PNe as well as to encourage the participation and collaborations between the PNe community and the multiple interdisciplinary research fields represented in NanoSpace.

We investigate the possible link between the Andromeda Giant Stream (AGS) and the 10 kpc ring structure using N-body/SPH simulations of a minor merger between the M31 and a satellite galaxy with a mass of 1010 M⊙. The simulation result successfully matches the observed features of the AGS and the 10 kpc ring concurrently. The simulation reproduced the observations, showing that the stars are smoothly distributed in the galactic disk, and the gas is shaped in a ring-like structure. In addition, we demonstrate the spatial metallicity distribution of the merger remnant, assuming the metallicity gradient of the progenitor galaxy. The result remarkably captures the observed features in the AGS exhibiting non-uniform metallicity distribution perpendicular to the AGS axis. These results indicate that a minor merger with a massive dwarf galaxy is capable of simultaneously forming the AGS and the 10 kpc ring.

We use all the Subaru/HSC-SSP photometric data to investigate spatial substructures in the outer halo of the Milky Way. In order to effectively detect them, an isochrone-filter is created for the old, metal-poor stellar systems on the color-magnitude diagram. As a result, previously discovered stellar streams (e.g. the Orphan Stream) are detected, while a new candidate substructure is discovered toward Pisces. Based on this filter, we conclude that the progenitor is an old and metal-poor system. This kind of stellar streams are expected to be found in the next-generation observation program.

The carbon-rich star V Hydrae is known to be in its transition from the asymptotic giant branch phase to a bipolar planetary nebula. However, the origin of its bipolar shape, as well as its long-term periodic obscuration, are not well understood. Using high-resolution spectra from the HERMES/Mercator spectrograph spanning over 10-yr monitoring, we disentangled the orbital signal from the intrinsic Mira-like variations of V Hya. The orbital solution obtained is compatible with the light-curve modulation, which we interpret as an obscuration caused by an extended dusty environment surrounding the unseen companion. Additionally, we report high-velocity phase-dependent absorption features in the sodium doublet and explain them by the presence of a conical jet ejected from the (accretion disc of the) companion. We confront our binary scenario with previous radio observations and discuss how this jet could shape the large-scale bipolar outflow of the system.

We correlate the annual Wolf numbers W and their time derivatives Wʹ by shifting time fragments of W and Wʹ relative to each other. The most significant (up to 0.874) correlation is with 3 years shifts for fragments covering 14 years. For longer and shorter periods, the correlation coefficients 0.771–0.855 with 2–3 years shift. The most significant 9 years shift corresponds to -0.852/-0.824 anti-correlation coefficient for 14/11 years period. The other periods are less significant. To evaluate predictive estimates, we use the times series fragments of W shifted back into the past. A forecast can be made using the leading graphs based upon the derived calibration factor. Test calculations show that the most effective is the calibration factor calculated for changing the phase of the cycle. The best linear pairwise correlation coefficient of the approximation is 0.94.

Statistical study of 3047 active regions (ARs) from 1996 to 2021 was performed using the catalog of the magneto-morphological classes (MMC) of ARs CrAO. According to the magneto-morphological classification of ARs proposed earlier, all ARs, except for unipolar spots, were sorted out between two categories: regular (bipolar groups obeying the Hale’s polarity law, the Joy’s law, etc.) and irregular ARs (all the rest). We analyzed the number and fluxes of ARs depending on their location in different (relative to the equator) hemispheres. We found that the trends for fluxes are more pronounced. For ARs of both MMC types, they demonstrate signs of both a multi-peak and double-peak structure. Some peaks coincide with the main maxima of the cycle. The second main maximum is mainly formed by the irregular ARs in the S-hemisphere. This might be due to the interaction of the dipole and quadrupole components of the global magnetic field.

OH masers are signpost of planetary nebulae (PNe) at a very young stage. In particular, Vy 2-2 was the first OH maser-emitting PN ever identified. It consists of a bright compact shell and a faint bipolar structure. The reported values for its O+2/H+ abundance discrepancy factor (ADF) are inconsistent:; 4.3, and; 11.8. To characterize the ionized gas and to redetermine the ADF(O+2), we have obtained medium-resolution optical spectra. We found that the ionized gas is oxygen-rich (C/O; 0.15), and an ADF(O+2); 13.6. Also, the N/O abundance ratio is; 0.39, implying a low-mass progenitor (Mi ≤ 1.5 Me). Unexpectedly, the detection of stellar weak emission lines (wels) suggests that the central star is carbon-rich. Alternatively, the wels may be emitted by an irradiated companion in a post-common envelope system. We have also obtained high-resolution optical spectroscopy on Vy 2-2. Our spectra kinematically resolve the bright shell and bipolar structure. We found that these expand at: 10 and: 20 km s-1, respectively.

Stellar activity depends on multiple parameters one of which is the age of the star. The members of open clusters are good targets to observe the activity at a given age of the stars since their ages are more precisely determined than that of field stars. Choosing multiple clusters, each with different age, gives us insight to the change in activity during the lifetime of stars. With the analysis of these stars we can also refine the parameters of gyrochronology (Barnes 2003), which is a method for estimating the age of low-mass, main sequence stars from their rotation periods.

On August 25 2013 Dana Patchick from the “Deep Sky Hunters” (DSH) amateur astronomer group discovered a diffuse nebulosity in the Wide-field Infrared Survey Explorer (WISE) mid-IR image archive that had no optical counterpart but appeared similar to many Planetary Nebulae (PNe) in WISE. As his 30th discovery he named it Pa 30 and it was added to the HASH PN database as a new PN candidate. Little did he know how important his discovery would become. 10 years later this object is the only known bound remnant of a violent double WD merger accompanied by a rare Type Iax SN, observed and recorded by the ancient Chinese and Japanese in 1181 AD. This makes Pa 30 and its central star IRAS 00500+6713 (WD J005311) the only SN Iax remnant in our Galaxy, the only known bound remnant of any SN, and based on the central star’s spectrum the only Wolf-Rayet star known that neither has a massive progenitor nor is the central star of a Planetary Nebula. We cover this story and our key role in it.

We present spectroscopy of NGC 3242, NGC 6153, and NGC 7009 at very high spectral resolution (λ / δλ = 75, 000 – 100, 000) obtained with the Manchester Echelle Spectrograph at the 2.1m telescope of the Observatorio Astronómico Nacional on the Sierra San Pedro Mártir. We study the kinematics of the plasma within the nebular shells, decomposing the observed line profiles considering the microscopic, macroscopic, and observational processes that broaden them. The residual kinematic structure, defined as the sum of velocity gradients, kinematic structure, and seeing dominates the broadening of the lines of heavy elements. We estimate the effect of velocity gradients, finding that it can account only for a minority of this residual kinematic structure. Whatever the origin of this residual kinematic structure, it is an important component of the kinematics of the ionized plasma within the nebular shell and implies an important energy source that is not contemplated in photoionization models of planetary nebulae.