During a WHT service night, ISIS spectra were obtained of six symbiotic stars and polarisation was confirmed to be clearly present in the 6825Å line in all the objects. Besides confirming the presence of Raman scattering, the observation revealed that there were structural variations in the degree and angle of polarisation across the line profile. This discovery now opens up the possibility of mapping the geometric structure of the neutral hydrogen scatter in three dimensions, because the Raman scattered emission lines contain velocity and vectorial polarisation information.
 

As a test of these ideas, the consortium called the "Lovers of Active Galaxies" observed the circum-nuclear region of the Seyfert 1 galaxy NGC 4151, using both the WHT and INT as part of and International Time Programme, looking for evidence of effects on the surrounding interstellar medium of ionizing radiation emitted by the nucleus. Like many Seyferts, NGC 4151 contains an extra-nuclear emission line region (ENLR) which is elongated over several kiloparsecs. The LAG consortium find that the ENLR emission line spectrum is characteristic of photoionization by a AGN continuum source and that the ionizing radiation field is very probably anisotropic.. Furthermore, the ionising parameter decreases with distance from the nucleus, consistent with geometrical dilution of the radiation of a central source. It is thought that ionising radiation from the nucleus could be being emitted into a broad cone whose axis is inclinned at a large angle to the plane of the galactic disk (by about 70 degrees) and that the ENLR is that segment of the disk which is illuminated by the cone. An elongated nuclear radio source is obsserved at an angle to the ENLR: the ejection axis of the radio-emitting plasma could conincide with the axis of the cone. This geometry is consistent with the fact that NGC 4151 is a Seyfert 1, since our line of sight would fall within the cone, giving a direct view of the nucleus.
 

One current theory of galaxy formation suggests that the necessary densities for the formation of halo stars occurred in dwarf galaxy sized objects which later merged. If this model is correct, the stellar debris of these initial clumps should now be scattered throughout the halo and groups of stars should exist on the same orbits as their parents dust clouds. Most theories also predict considerable later accretion of halo stars from disrupted satellite galaxies, the remnants of which would also be on similar orbits. The kinematic streams should be detectable. Researchers have developed a selection technique to obtain high probability samples of halo blue horizontal branch (BHB) stars, using both direct and objective prism UK Schmidt plates scanned by the APM. The technique reliably eliminates white dwarf stars, quasars, hot subdwarfs and faint galaxies. 44 candidates were selected in this way in two fields using ISIS on the WHT; they identified 25 stars with A-type spectra in one field and 11 in another, and determined their velocities and distances. The dispersion of velocities of four stars in one field at 30kpc from the Sun is very low, 12 km sec^-1, and suggests that these stars are physically associated and may have had a commonn origin. The remaining kinematic data show the Galaxy to have a massive halo extending to at least 30kpc with a flat rotation curve.
 

Researchers used the INT and the AAT to measure the primordial helium abundance from the emission lines of HII galaxies. Combined with selected data from the literature relating to extragalactic HII regions in general, they determined Y to be 0.228±0.005 or Y < 0.242 with 95 per cent confidence. This value places in turn an upper limit of 10.4 minutes on the half-life of the neutron and limits the number of neutrino species to < 3.2. These limits based on purely astronomical work, have been confirmed by experiments in the laboratory (10.25 minutes and 3.01±0.01 species). In the course of this work, HII galaxies with broad Wolf-Rayet emission features were excluded from the analysis since they often showed higher helium abundance, supporting a suggestion that there may be additional local sources of helium in the form of winds from Wolf-Rayet stars. 
 

The light curves of newly discovered supernovae will be monitored over the period of visibility to determine their types, and in the case of type Ia discoveries their "standard candle" properties will be used to measure their distances. The distances and redshifts combined will provide a measure of the decleration parameter of the Universe to the critical density.

As part of this campaign, one type Ia supernova has already been discovered in a distant galaxy. The new supernova was detected at R=22mag on an INT CCD prime focus image and then confirmed in follow-up images over a period of weeks. A spectrum of the host galaxy was obtained with the WHT and the redshift measured to be z=0.457, making it the most distant supernova ever observed.
 

OTHER HIGHLIGHTS 

The WHT and INT were used in a survey of high latitude IRAS objects to look for Seyfert galaxies. The results confirmed a model whereby the 2 types of Seyfert galaxies are due to obscuration, coming from a single population.

ISIS on the WHT was used to demonstrate that the standard methods of obtaining velocity dispersions of galaxies could lead to wrong answers. More sophisticated models are therefore needed to fir the nuclei of galaxies better.

The WHT was used with adaptive optics to detect yellow supergiants, which act as standard candles, in NGC 4532. A value of 80 kms^-1Mpc^-1 for the Hubble constant was obtained, though lower values may be allowed.

INT images have been used to reconfirm the accepted fact that spiral disks are optically thin at optical wavelengths. There had been some new models put forward which had cast doubt on the previous results, but observations of NGC 450 and UGC 807 have shown that there is no absorbtion and that the disks are transparent.

Ultra-high resolution images of the core of M15 were obtained using the WHT and GHRIL, followed by computer post exposure sharpening (TRIFFID). It was used to examine an X-ray binary near the centre of M15. Only the HST has been able to take better images than this.

An extensive programme was carried out on the JKT to measure photometry of thousands of binary stars.