The early identification of the strong X-ray source in Taurus with the Crab nebula (Bowyer et al. 1964) was the first milestone in the association of X-ray emission with supernova remnants. Unfortunately, it proved to be “red herring” which clouded the interpretation of X-ray emission from supernova remnants for a decade. Because the Crab was one of the brightest X-ray sources in the sky at a few keV, the interrogation energy of the early surveys, and because it was the first (and for several years the only) X-ray source conclusively identified, the potential association of a supernova origin with the large body of unidentified X-ray sources was not an unreasonable hypothesis.

Astronomers have always had a special need for rapid communication over large distances, partly because of their interest in experiments requiring long baselines. Examples: Eratosthenes’ measurement of the circumference of the Earth; determination of longitude at sea; solar-eclipse tests of general relativity; very-long-baseline interferometry. Of these, at least the second has prompted innovations in communications techniques (beginning with the Greenwich time ball).

More recently, the pressing need to travel widely for clean air and aether, and the international flavour of the resulting collaborations, has given astronomers particular incentive to explore the latest communications innovation: electronic mail.

Glassy spherules ranging from 200 μ to 62 μ in size have been separated from lunar dust samples No. 12001.73, 12057.60, 12070.37. Most of them are regular in size (spherical, ellipsoidic, dumbbell, teardrop, etc.); some are irregularly shaped.

A tentative dynamical model of the evolution of a rotating melted spherical drop of homogeneous glassy material has been built in order to explain the observed forms. We suppose such fluid to be originated from the impact of meteoroids on the lunar surface. The energy balance between the projectile (meteoroid) and the target (lunar surface) has been calculated supposing that the impact gives rise to strong shock waves in both bodies.

Equations of the model have been solved numerically and a good agreement between these results and the experimental data regarding small spherules has been obtained.

In our studies of activity in pre-main sequence Herbig Ae/Be stars we are mainly interested in searching rotational modulation of line profile. If the period of star rotation is of the order of one or two days, the data collected from a single site is insufficient. This led us to start correlated observations from two or three sites spread as much as possible in longitude. Our first bi-site observations started in 1982 on AB Aur from two observatories located 11 hours apart.: CFHT in Hawaï and OHP in France. To achieve a high flexibility and to gain access to telescopes without attached spectrographs. We built an instrument that is mobile and specially designed for line profile studies.

From line and continuun data of the ultraviolet and visible spectrum of 48 Lib, the fundamental parameters of the circumstellar envelope are derived.

From measurements of Tautenburg Schmidt plates with the APM in Cambridge positional accuracies per plate of 0.″05 for stars and of 0.″10 for galaxies were achieved. With 0.″3/100a accuracy in a single stellar proper motion we obtained the absolute proper motion of the M3 globular cluster in good agreement between the two pairs of plates used.

Since January 1995 the International GPS Service (IGS) has been combining and analyzing daily polar motion (PM) series, produced and submitted by seven IGS analysis centers (ACs) for the IGS Final orbit/clock combinations. Since June 30, 1996 the IGS Earth Rotation Parameter (ERP) series that accompany the IGS combined orbits, also include combined PM rates. Furthermore, since March 1997, the IGS LOD (Length of Day) solutions are based on separate combinations of AC LOD solutions calibrated and weighted according to the IERS Bulletin A definite values. Similar to AC orbit solutions, the PM solutions have improved considerably since 1995, so that currently the IGS combined and the best AC PM solutions are at or below the 0.1 mas precision level, although PM biases may exceed .1 mas. Comparisons of AC ERP and PM rate solutions with the IGS Final combined ERP series revealed signals with 7 and 14-day periods for some AC solutions.

During 1998, the IGS Final and the best AC PM rate solutions compared with Atmospheric Angular Momentum (AAM) at 0.3 mas/day (rms) with an average correlation of about 0.8 and 0.6 for the PM x and PM y rate components. The correlation varied considerably with time and frequency, though significant correlation already started from 6-day periods and reaching maxima within 10 to 50 day period bands. Most of the remaining signal in the PM rate solutions could likely be accounted for by Ocean Angular Momentum (OAM) as seen from the comparisons of combined OAM and AAM with the IGS PM series during 1995 and early 1996 when also OAM data were made available. During this period the IGS PM rates agreed with the combined OAM + AAM series with 0.3 and 0.2 mas/day (rms) for the PM x and y components and with an average correlation of about 0.8 for both PM components.

A miniaturized spectrometer designed for mounting at the Cassegrain focus of a 40 cm telescope has been built and laboratory tested with promising results. The optical system consists of a slit, spherical mirror, and reflection grating in a Littrow configuration. The detector is a 128 element linear CCD cooled by an evacuated microminiature nitrogen refrigerator and interfaced to a microcomputer using direct memory access. Laboratory spectra of a mercury vapor discharge tube have been obtained and demonstrate 1 Angstrom resolution with low noise. The spectral coverage of about 100 Angstroms is suitable for measurement of stellar H-alpha line profiles, and it is anticipated that the instrument can be used to monitor bright Be stars.

The 4 configuration, distorted wave calculation of Bhatia & Doschek (1995) (hereafter referred to as BD95), together with the ground transition calculation of Pelan & Berrington (1995) are here used to predict the intensities of the Fe X EUV lines, which are then used to derive electron densities from several solar spectra, including the recent SERTS spectra.

HRCAM (High Resolution CAMera) is a Canon 50D 15-megapixel digital SLR camera equipped with a Sigma 4.5 mm f/2.8 fish-eye lens. It was installed at Dome A on the Antarctic plateau in January 2010 and photographs the sky every 15 minutes. Primarily functioning as a site-testing instrument, data obtained from HRCAM provide valuable statistics on cloud cover, sky transparency and the distribution and frequency of auroral activity. We present a first look at data from HRCAM during 2010, including an overview of how we intend to reduce the images. We also demonstrate the potential of stellar photometry by using linear combinations of the in-built Canon RGB filters to convert instrumental magnitudes into the photometric BVR bands.

Details of the organization of the 1887 astrophotographic congress have been traced in Paris Observatory archives. The following points have been especially examined: invitations, practical organization, budget, decorations and reports edition. Amiral Mouchez personality becomes apparent after the factual knowledge.

Work in progress at Steward Observatory covering three aspects of magnetism in degenerate dwarfs is reviewed. First, the identification of the Minkowski bands in Grw + 70° 8247 with Zeeman transitions in hydrogen. Second, a determination of field strengths in the more strongly magnetic white dwarfs. Third, some observations and speculations concerning the origin of white dwarf and neutron star magnetic fields.

An observational study of the Hα feature in Algol type binary systems has revealed the presence of emission in nearly all systems with periods greater than 6 days. The disks which produce this emission are generally thin and can extend out to 90% of the Roche surface of the primary star. If emission is found in the systems of shorter period, it tends to be transient, lasting only a few orbital cycles. In several systems, there is evidence of mass loss from the vicinity of the primary at phase 0.5.

The observational base of our investigation consists of a two-dimensional MK classification of about 11.000 stars in the 42 Kapteyn Areas situated along the gal.lat-s from −17° up to +72° and 200 Ap, Am stars discovered in the same KA. The dispersion of the applied objective-prism spectra is 160 Â per mm. The data are of high accuracy, close to the Michigan level, and uniformity, which make them reliable. The limit is close to the 12-th ph.mg.

The general conclusion of the undoubted importance is stated: the galactic concentration of dwarfs is closer than it had been assumed until now; on the other hand - the giants are not so closely concentrated to the galactic plane as it has been accepted.

We searched for isolated galaxies, pairs and groups of galaxies in the CfA survey (Huchra et al. 1983). It was assumed that the distances to galaxies are given by R = V/H0, where H0 = 100 km s−1 Mpc−1 and R> 6 Mpc.

The masses of 6 neutron stars have now been established through studies of binary X-ray and radio pulsars. All of the masses are found to be consistent with, but not necessarily constrained to, the range 1.2–1.6 M⊙. In this talk we discuss the methods and assumptions used in determining the masses of neutron stars in binary X-ray pulsar systems. For other recent reviews of this subject, the reader is referred to Bahcall (1978), Rappaport and Joss (1981), and references therein. Neutron-star parameters may also be obtained from studies of X-ray bursts that result from thermonuclear flashes near the surface of an accreting neutron star (see Joss 1980 and references therein), which we will not discuss here.

Some observable relationships between globular cluster parameters appear as a result of long time dynamical evolution of the cluster system. These relationships are inapplicable to the studies of the globular clusters origin.

This summary reports new emission lines of Fe XVII observed in two coronal active regions (McMath regions 12624, 12628). The lines were recorded by a Bragg plane crystal spectrometer collimated to 3′ FWHM, with a gypsum crystal scanning the wavelength range 8–14 Å. This spectrometer, part of a three spectrometer package previously used by Parkinson (1972, 1973), was mounted aboard a Skylark rocket (SL 1206) launched from Woomera at 0535 UT on 26th November 1973. One of the active regions studied (12624) was observed about 60 minutes after the peak of an importance – N class CO flare.

This paper is a review of some of the recent modeling efforts to improve our understanding of structure formation and evolution of planetary nebulae including their interaction with the interstellar medium. New propositions have been made for the formation mechanism of multi-polar PNe and PPNe. These mechanisms are based on the central engine with interacting binary stars or hole producing instabilities in expanding shock waves leading to illumination effects from the central star that change the appearance of the nebula. Furthermore, there has been a lot of progress in the observation and 3D modeling of the kinematics, which is key to the understanding of the dynamics. Extensive observational catalogs are coming online for the kinematics, as well as some very detailed proper motion measurements have been made. New techniques for morpho–kinematic 3D modeling help to make the interpretation of kinematic data more reliable and detailed. In addition to individual pointed observations, new surveys have lead to the discovery of many PNe that show clear signs of interaction with the interstellar medium. Systematic hydrodynamic models of the interaction have produced a general scheme for the observed structure that results from the interaction of an evolving planetary nebula with the ISM. Detailed modeling of the dust-gas dynamics during the interaction with the ISM have produced interesting predictions for future IR observations. Detailed models were worked out for the structure of the bowshock and tail of Mira that was recently discovered in the UV.