Probably, the long-term monitoring of the solar atmosphere started in Italy with the first telescopic observations of the Sun made by Galileo Galilei in the early 17th century. His recorded observations and science results, as well as the work carried out by other following outstanding Italian astronomers inspired the start of institutional programs of regular solar observations at the Arcetri, Catania, and Rome Observatories.

These programs have accumulated daily images of the solar photosphere and chromosphere taken at various spectral bands over a time span larger than 80 years. In the last two decades, regular solar observations were continued with digital cameras only at the Catania and Rome Observatories, which are now part of the INAF National Institute for Astrophysics. At the two sites, daily solar images are taken at the photospheric G-band, Blue (λ = 409.4 nm), and Red (λ = 606.9 nm) continua spectral ranges and at the chromospheric Ca II K and Hα lines, with a 2″ spatial resolution.

Solar observation in Italy, which benefits from over 2500 hours of yearly sunshine, currently aims at the operational monitoring of solar activity and long-term variability and at the continuation of the historical series as well. Existing instruments will be soon enriched by the SAMM double channel telescope equipped with magneto-optical filters that will enable the tomography of the solar atmosphere with simultaneous observations at the K I 769.9 nm and Na I D 589.0 nm lines. In this contribution, we present the available observations and outline their scientific relevance.

The thick disc is a major component of the Milky Way but its epoch of formation and characteristics are still not yet well constrained. The Besançon Galaxy Model (BGM, Robin et al. 2003) is a population synthesis model based on a scenario of formation and evolution of the Galaxy, a star formation history, and a set of stellar evolution models. Thanks to Lagarde et al. (2017), new evolutionary tracks have been introduced into the Besancon Galaxy Model (STAREVOL, Lagarde et al. 2012) to provide global asteroseismic and surface chemical properties along the evolutionary stages. This updated Galaxy model will allow us to constrain the thick disc structure and history using the Markov Chain Monte Carlo fitting method (MCMC). We show preliminary results applying this MCMC method on the 2MASS photometric survey.

We present the initial results from a class I 44-GHz methanol maser follow-up survey, observed with the MOPRA telescope, towards 272 sources from the Methanol Multi-beam survey (MMB). Over half (∼60%) of the 6.7 GHz class II MMB maser sources are associated with a class I 44-GHz methanol maser at a greater than 5σ detection level. We find that class II MMB masers sources with an associated class I methanol maser have stronger peak fluxes compared to regions without an associated class I maser. Furthermore, as part of the MOPRA follow-up observations we simultaneously observed SiO emission which is a known tracer of shocks and outflows in massive star forming regions. The presence of SiO emission, and potentially outflows, is found to be strongly associated with the detection of class I maser emission in these regions.

The nearest millisecond pulsar PSR J0437–4715 is the ideal target to constrain the dense matter equation of state using the lightcurve modelling method. Our analysis combining XMM-Newton, NuSTAR, and ROSAT observations removed ambiguities in the spectral modelling of the surface emission from PSR J0437–4715. Furthermore, the NuSTAR observation demonstrated that the non-thermal hard tail emission was pulsed at the pulsar spin period. These features are crucial to model the lightcurve and to measure the radius of the neutron star. This conference proceeding is based on the publication Guillot et al. (2016).

PSR J0337+1715 is a millisecond radio pulsar in a hierarchical stellar triple system with two white dwarfs. This system is a unique and excellent laboratory in which to test the strong equivalence principle (SEP) of general relativity. An initial SEP-violation test was performed using direct 3-body numerical integration of the orbit in order to model the more than 25000 pulse times of arrival (TOAs) from three radio telescopes: Arecibo, Green Bank and Westerbork. In this work I present our efforts to quantify the effects of systematics in the TOAs and timing residuals, which limit the precision of an SEP test. In particular, we apply Fourier-based techniques to the timing residuals in order to isolate the effects of systematics that can masquerade as an SEP violation.

Extreme solar storms are well known in the historical databases. Since the modern era, it has been possible to associate clearly geomagnetic disturbances with solar events (flares, SEP, CMEs). In the recent solar cycles the geoeffective events (number and strength) are decreasing. As an example, in the 2002 maximum activity year, we present how many flares, and CMEs were geoeffective. Based on observations and simulations, we discuss on the size of sunspots and the field strength to get more energetic flares (> 1032 ergs) in the near future.

A strong outburst of 6.7 GHz methanol maser occurred in the high-mass young stellar object (HMYSO) G24.33+0.14 between November 2010 and January 2013. The target was observed with the Torun 32 m radio telescope as a part of a long-term monitoring programme. Almost all twelve spectral features from 108 to 120 km s−1 varied synchronously with time delays between the flux minima of about two weeks. This may indicate that the variability is driven by global changes in the pump rate. The flare peaks of the two features with the highest relative amplitude of 40-60 are delayed by about 2.5 months while their profiles undergo essential transformation with a velocity drift of 0.23 km s−1yr−1. This may suggest that the variability is caused by a rapid increase of the pump rate and excitation of a large portion of the HMYSO environment by an accretion event.

The Milky Way (MW) is interacting with its satellite galaxies and the tidal remnants of satellite galaxies have been observed especially in the MW halo. Understanding the spatial and velocity distributions of stars stripped from satellite galaxies will be of particular importance when interpreting the data from upcoming observations, such as Gaia, Subaru-HSC and PFS. We study tidal stripping events of satellite galaxies with various internal structures using high resolution N-body simulations. The dynamics of satellite galaxies is dominated by dark matter halos, but their density structure is still uncertain. The simulations reveal satellite galaxies with more tightly bound dark matter halos are more robust against the tidal force of the MW and have longer lifetimes than loosely bound ones (Ogiya et al., in prep.). Density scratches on the MW caused by the gravitational force of satellite galaxies and the observability are also discussed (Ogiya & Burkert 2016).

Methanol masers observed at high angular resolution are useful tool to investigate the processes of high-mass star formation. Here, we present the results of statistical analysis of the 6.7 GHz methanol maser structures in 60 sources observed with the EVN. The parameters of the maser clouds and exciting stars were derived. There is evidence that the emission structures composed of larger number of maser clouds are formed in the vicinity of more luminous exciting stars.

Active sun is characterized by compelling short-lived flash of solar eruption like solar flare, coronal mass ejections (CMEs), high-speed solar winds and solar energetic particles along with colossal release of energy and mass. This paper proposes a new method to evaluate solar wind parameters and geomagnetic indices based on wavelet analysis during the solar flares. The crucial role of IMF-Bz (interplanetary magnetic field) is examined for the two solar flares events. The key result obtained from our study is substantial dependence of solar flare intensity on IMF-Bz together with solar wind velocity. We also observed the duration of solar flares and their effect on ionospheric and ground based parameters.

If the observed parallax ϖ′ has a gaussian measurement error σ, there is a 68% probability that the actual parallax ϖ is in the range ϖ′ − σ < ϖ < ϖ′ + σ (the frequentist approach). The probability distribution within this range is not known from ϖ′ and σ alone, and in particular, we cannot state that the most probable distance D is given by D = 1/ϖ′. To obtain a probability distribution, we need to know or assume a distribution of pulsar distances. Similar assumptions are also required to estimate the velocity distribution of radio pulsars.

Using the VLBA, the BeSSeL survey has provided distances and proper motions of young massive stars, allowing an accurate measure of the Galactic spiral structure. By the same technique, we are planning to map the inner Galaxy using positions and velocities of evolved stars (provided by the BAaDE survey). These radio astrometric measurements (BeSSeL and BAaDE) will be complementary to Gaia results and the overlap will provide important clues on the intrinsic properties and population distribution of the stars in the bulge.

Methanol masers at 6.7 GHz are the brightest of class II methanol masers and have been found exclusively towards massive star forming regions. These masers can thus be used as a unique tool to probe the early phases of massive star formation. We present here the SED studies of 284 methanol masers chosen from the MMB catalogue, which falls in the Hi-GAL range (|l| ≤ 60°, |b| ≤ 1°). The masers are studied using the ATLASGAL, MIPSGAL and Hi-GAL data at wavelengths ranging from 24−870 micrometers. A single grey body component fit was used to model the cold dust emission whereas the emission from the warm dust is modelled by a black body. The clump properties such as isothermal mass, FIR luminosity and MIR luminosity were obtained using the best fit parameters of the SED fits. We discuss the physical properties of the sources and explore the evolutionary stages of the sources having 6.7 GHz maser emission in the timeline of high mass star formation.

Since the first light of the 2.4-m Thai National Telescope in 2013, Thailand foresees another great leap forward in astronomy. A project known as “Radio Astronomy Network and Geodesy for Development” (RANGD) by National Astronomical Research Institute of Thailand (NARIT) has been approved for year 2017-2021. A 40-m radio telescope has been planned to operate up to 115-GHz observation with prime-focus capability for low frequency and phased array feed receivers. The telescope’s first light is expected in late 2019 with a cryogenics K-band and L-band receivers. RFI environment at the site has been investigated and shown to be at reasonable level. A 13-m VGOS telescope is also included for geodetic applications. Early single-dish science will focus on time domain observations, such as pulsars and transients, outbursts and variability of maser and AGN sources.

The RAVE survey obtains moderate-resolution (R ~ 7500) spectroscopy of relatively bright stars in the region of the Ca triplet, and derives estimates of stellar atmospheric parameters (Teff, log g, and [Fe/H]) and abundance estimates for a limited number of elements. The RAVE sample is selected on apparent magnitude, effectively removing the biases typically associated with searches for metal-poor stars such as metallicity, evolutionary status, or Galactic population membership. For the past several years, we have been obtaining medium-resolution (R ~ 1800) spectroscopy over a much wider wavelength range, from 3700 Å to 5500 Å, for RAVE stars with estimated metallicities from the RAVE pipeline of [Fe/H] < −1.8.

Based on these observations, we use the well-tested n-SSPP pipeline to obtain atmospheric parameter estimates, as well as measurements of [C/Fe], for over 1,700 metal-poor star candidates. We present an analysis of the distribution of carbon-enhancement in the relatively local volume of the Galaxy as a function of metallicity, location, and kinematics. Our results are useful to test the RAVE parameter estimates, and add to the growing number of known carbon-enhanced metal-poor (CEMP) stars for future high-resolution follow-up.

Sunspot activity exhibits hemispheric asymmetry. We study the long-term variations in the hemispheric sunspot area from Kodaikanal white-light data during 1921 – 2011. The results on the presence or absence of double peak in an individual solar cycle, dominant hemispheric activity, and phase lag between the activities of northern and southern hemispheres, etc., are presented.

Hemispheric asymmetry is one of the significant parameters related to the action of solar dynamo. Comparison of hemispheric activities during various phases are found out for solar cycles 12 to 23. Asymmetry of solar activity shows extremum values during the cycles 14 and 19. Lowest and highest levels of north-south asymmetry are mainly observed during minimum and maximum phases respectively of solar cycles. A change of phase is found to be existing between the asymmetries at solar maxima and the whole cycle, after solar cycle 15 and 18. Also, for cycles 17-19, the behaviour of the asymmetry is observed to be peculiar and different from that of the other cycles. Periodic behaviour of north-south asymmetry mainly occurs in 8.8 years and noticed very high during the cycles 18-22.

We present simultaneous multi-frequency observations of PSR J1822–2256 for the first time, utilizing the unique capabilities of upgraded Giant Meterwave Radio Telescope (uGMRT). No emission is detected in about 10 % of pulses. At least two drift modes and a possibly third rare mode, occur for 66, 21 and 2 % pulses respectively (P3 ~ 17, 7.5 and 5 P0 respectively). The three drift modes and the nulls occur concurrently from 250 to 1500 MHz. Modal average profiles are distinct with their widths increasing with drift rate. These sub-pulse drift related profile mode-changes can provide independent probes of beam geometry and polar gap physics.

The age-metallicity relation (AMR) is a fundamental observational constraint for understanding how the Galactic disc formed and evolved chemically in time. However, there is not yet an agreement on the observational properties of the AMR, primarily due to the difficulty in obtaining accurate ages for individual field stars. We have started an observational campaign for providing new observational input by using wide white dwarf-main sequence (WDMS) binaries. WDs are natural clocks and can be used to derive accurate ages. Metallicities can be obtained from the MS companions. Since the progenitors of WDs and the MS stars were born at the same time, WDMS provide a unique opportunity to constrain in a robust way the properties of the AMR. We present the AMR derived from analysing a pilot sample of 23 WDMS and provide clear evidence for the lack of correlation between age and metallicity at young and intermediate ages.