In this review we present a short introduction to the X-ray Telescope on Hinode. We discuss its capabilities and new features and compare it with Yohkoh SXT. We also discuss some of the first results that include observations of X-ray jets in coronal holes, shear change in flares, sigmoid eruptions and evolution, application of filter ratios and differential emission measure analysis, structure of active regions, fine structure of X-ray bright points, and modeling non-potential fields around filaments. Finally, we describe how XRT works with other ground and space-based instrumentation, in particular with TRACE, EIS, SOT, and SOLIS.

The business session of the Working Group followed the completion of Special Session 7, Astronomy in Antarctica. The proceedings of this meeting are published in Highlights in Astronomy, Volume 14 (Ed. K. A. van der Hucht, 2007, CUP). The session involved 18 papers spread over 5 sessions, together with a further 18 poster papers. A dinner was also held in Prague following the first day of the Special Session.

We discuss astrometric capabilities of the future interferometer ALMA that will be located at a high altitude site (5000m) in Northern Chile to operate in the sub-millimeter range. In this paper, we estimate the astrometric precision of ALMA to be ~0.18 milliarcsecond at the optimum observing frequency of 345 GHz from an error budget including the thermal noise and the systematic errors caused by uncertainties in antenna coordinates, reference source coordinates, Earth orientation parameters, dry atmosphere parameter and by phase fluctuations due to moisture above the site. We briefly discuss three applications: first, astrometric search of exoplanets around 446 nearby stars detectable by ALMA; second, proper motions and parallaxes of pre-stellar cores and protostars; third, the rotation rate of the debris disk around ε Eri to test the theory of dust trapping in mean motion resonances with unseen planets.

MERLIN observations of 6.668-GHz Methanol and 6.035-GHz OH emission from the known massive star-formation region ON1 are presented. Maser components are found to lie at the southern edge of the UCHII with consistent polarization angles across the strongest features. Zeeman splitting of OH shows magnetic field strengths between +0.4 to −5.3 mG and from cross-correlation a tentative methanol magnetic field of −18mG is detected.

I discuss my stellar evolution code Ev in the context of simulations of large clusters of stars. It has long been able to handle single stars, and also binary stars up to a point. That point is far beyond what other codes are able to do, but well short of what is necessary for believable simulations. A recent version, Ev(Twin), can in principle deal with the contact phase of binary evolution, but it is not yet clear what the physical interaction is that needs to be simulated.

An upgrade, which I hope will be only a few lines, should allow it to follow Kozai cycles with tidal friction, a process that strongly influences the orbital period of close pairs that reside within wide, non-coplanar triples. However, there are many substantial gaps in the physics of even single stars, let alone binaries or triples.

We have investigated accretion of terrestrial planets from planetesimals around M dwarfs through N-body simulations including the effect of tidal interaction with disk gas. Because of low luminosity of M dwarfs, habitable zones around them are located near the disk inner edge. Planetary embryos undergo type-I migration and pile up near the disk inner edge. We found that after repeated close scatterings and occasional collisions, three or four planets eventually remain in stable orbits in their mean motion resonances. Furthermore, large amount of water-rich planetesimals rapidly migrate to the terrestrial planet regions from outside of the snow line, so that formed planets in these regions have much more water contents than those around solar-type stars.

We present recent results showing that a large fraction of red sequence galaxies contain ionized gas with LINER-like optical emission line ratios. This emission is more frequently found in galaxies with lower central velocity dispersion (σ) and these galaxies typically have younger mean ages than galaxies at the same σ which do not host emission. We suggest that the presence of LINER-like emission may be determined by the quantity of interstellar material in these galaxies and may be associated with the recent accretion of a gas-rich satellite galaxy or alternatively with stellar mass loss that declines as the galaxy stellar population ages.

We present 21 cm observations of 5×1 square degrees centered on the local Abell cluster 1367 obtained as part of the Arecibo Galaxy Environment Survey. This represents the first HI selected sample covering the core and the outskirts of a local cluster of galaxies. Combining the HI data with SDSS optical imaging we show that in HI selected samples follow scaling relations similar to the ones usually observed in optically selected samples. The most striking difference between HI and optically selected samples resides in their large scale distribution: while optical and X-ray observations trace the cluster potential very well, at radio wavelengths there is almost no evidence of the cluster presence.

It was shown in a previous paper (Ibáñez 2004) that for certain kind of plasmas the coefficient of second (bulk) viscosity can be orders of magnitude larger than the coefficients corresponding to the dynamical viscosity and to the thermometric conductivity. In the present paper, the damping effects of the second viscosity on the hydromagnetic waves propagation are analyzed. In particular, we study the effect of the second viscosity on the magnetoacustic waves propagating in a photoionized gas of arbitrary metallicity Z and mean energy E of the ionizing photons when an initial steady magnetic field H is present.

The five years that have passed since the last IAU Symposium devoted to massive stars have seen a veritable explosion of data on the high redshift universe. The tools developed to study massive stars in nearby galaxies are finding increasing application to the analysis of the spectra of star-forming regions at redshifts as high as z = 7. In this brief review, I consider three topics of relevance to this symposium: the determination of the metallicities of galaxies at high redshifts from consideration of their ultraviolet stellar spectra; constraints on the initial mass function of massive stars in galaxies at z = 2 − 3; and new clues to the nucleosynthesis of carbon and nitrogen in massive stars of low metallicity. The review concludes with a look ahead at some of the questions that may occupy us for the next five years (at least!).

The same general claims hold true as in the last report and the field is as busy as ever. Community focus is on the deployment of large mosaics (up to 108 pixels) to telescopes, the pursuit of programs to build next generation mosaics (of order 109 pixels), and the investigation of novel variations in CCD design.

In this paper we study non-axisymmetric oscillations of thin twisted magnetic tubes taking the density variation along the tube into account. We use the approximation of the zero-beta plasma. The magnetic field outside the tube is straight and homogeneous, however it is twisted inside the tube. We assume that the azimuthal component of the magnetic field is proportional to the distance from the tube axis, and that the tube is only weakly twisted, i.e. the ratio of the azimuthal and axial components of the magnetic field is small. Using the asymptotic analysis we show that the eigenmodes and eigenfrequencies of the kink and fluting oscillations are described by a classical Sturm-Liouville problem for a second order ordinary differential equation. The main result is that the twist does not affect the kink mode.

We present recent progress in searching for galaxies at redshift from z ≃ 5 to z ∼ 10. Wide-field and sensitive surveys with 8m class telescopes have been providing more than several hundreds of star forming galaxies at z ∼ 5 − 7 that are probed in the optical window. These galaxies are used to study the early cosmic star formation activity as well as the early structure formation in the universe. Moreover, near infrared deep imaging and spectroscopic surveys have found probable candidates of galaxies from z ∼ 7 to z ∼ 10. Although these candidates are too faint to be identified unambiguously, we human being are now going to the universe beyond 13 billion light years, close to the epoch of first-generations stars; i.e., Population III stars. We also mention about challenges to find Population III-dominated galaxies in the early universe.

In this report we give a brief introduction to the Five hundred meter Apeture Spherical Telescope (FAST). Some possible contributions of FAST to high precision astrometry are discussed. The illuminated aperture of FAST in normal operation mode is 300m in diameter. With special feeding mechanism, the whole 500m aperture could be used. FAST will cover frequencies from 70MHz to 3GHz, and observe at zenith angle of up to 40 degrees without a notable gain loss. As the most sensitive single dish radio telescope, FAST would be able to discover more mega-masers and measure the radial velocities of masers with higher precision. This may yield more delicate dynamics of their maser spots. FAST will increase the precision of time of arrival (ToA) measurements for pulsars. This will help in detecting the stochastic gravitational wave background and in establishing an independent timing standard based on the long-term stability of the rotations of a group of millisecond pulsars. FAST might also work as a very powerful ground station for the future space missions. In a three-way communication mode, FAST should be able to provide precise ranging and Doppler measurements. Moreover, by joining the international VLBI network, FAST would help to improve the precision of the VLBI astrometry measurements.

Encounters between binary stars and single stars and between binary stars and other binary stars play a key role in the dynamics of dense stellar systems. In the simple model, in which stars are approximated by point masses, a number of theoretical and numerical results are known. In particular there exist relationships to help to describe the destruction process of binary stars (ionisation) through three-body encounters between binary and single stars. Here we extend these results to the four-body case involving encounters between pairs of binary stars that lead to a disruption of the binaries into single stars.

We present preliminary results of a study of the low frequency radio continuum emission from the nuclei of Giant Low Surface Brightness (LSB) galaxies. We have mapped the emission and searched for extended features such as radio lobes/jets associated with AGN activity. LSB galaxies are poor in star formation and generally less evolved compared to nearby bright spirals. This paper presents low frequency observations of 3 galaxies; PGC 045080 at 1.4 GHz, 610 MHz, 325MHz, UGC 1922 at 610 MHz and UGC 6614 at 610 MHz. The observations were done with the GMRT. Radio cores as well as extended structures were detected and mapped in all three galaxies; the extended emission may be assocated with jets/lobes associated with AGN activity. Our results indicate that although these galaxies are optically dim, their nuclei can host AGN that are bright in the radio domain.

We present first results from an imaging survey with the Spitzer Space Telescope of 62 brightest cluster galaxies with optical line emission located in the cores of X-ray luminous clusters selected from the ROSAT All-Sky Survey. We find that 1/3 of these sources have signs of excess infrared emission; 22 objects of 62 are detected at 70 μm and 19 have 8 to 5.8 μm flux ratios above 0.98. The strength of the excess emission correlates with the luminosity of the optical emission lines. Excluding the four systems dominated by an AGN, the excess mid-infrared emission in the remaining brightest cluster galaxies is likely powered by star formation. We find a correlation between mass deposition rate from a cooling flow model for the X-ray emission and the star formation rate estimated from the infrared luminosity. The star formation rates are 1/10 to 1/100 of the mass deposition rates expected in the absence of heating suggesting that the re-heating of the ICM is generally very effective in reducing the amount of mass cooling from the hot phase.

Suppression of type I migration is essential for the retention of protoplanetary cores which are sufficiently massive to accrete gas in their nascent disks and evolve into gas giant planets. We explore here the possibility that special disk properties at the snow line may be the dominant process which stalled the type I migration. We simply use a 1-D model to calculate the torque with linear formula and find that, if the surface density jump near snowline is great enough, the migration can be efficiently slowed down or even halted. This mechanism offers an explanation to the observed peak, at 2–3 AU, in the extra solar planets' semi major axis distribution.

In the course of following up compact methanol masers at 6.7 GHz which were found in the Torun blind survey (Szymczak et al. 2002), we discovered a ring structure in the source G23.657−00.127. This source provides interesting insights into whether methanol masers arise in rotating disks around massive stars, in their outflows, or behind shocks. By monitoring the 12.2 GHz masers, which fortunately follow the same structure, we hope to resolve the kinematics of the ring. Moreover, the symmetry of the source points to the existence of a central source. Early results on the nature of this source indicate the existence of a hyper–compact H II region.

Commission 25 is one of three Commissions under the umbrella of Division IX on Optical and Infrared Techniques. It is a technique oriented Commission.