In the ROSAT era of the mid-1990's, the problems facing deep X-ray surveys could be largely solved with 10 m class telescopes. In the first decade of this new millennium, with X-ray telescopes such as the Chandra X-ray Observatory and XMM-Newton in operation, deep X-ray surveys are challenging 10 m telescopes. For example, in the Chandra Deep Field surveys, ≈ 30% of the X-ray sources have optical counterparts fainter than R=25 (I=24). This paper reviews current progress with 6-10 m class telescopes in following up sources discovered in deep X-ray surveys, including results from several X-ray surveys which have depended on telescopes such as Keck, VLT and HET. Topics include the prospects for detecting extreme redshift (z > 6) quasars and the first detections of normal and starburst galaxies at cosmologically interesting distances in the X-ray band. X-ray astronomy can significantly bolster the science case for the next generation of large aperture (30-100 m) ground-based telescopes and has already provided targets for these large telescopes through the Chandra and XMM-Newton surveys. The next generation of X-ray telescopes will continue to challenge large optical telescopes; this review concludes with a discussion of prospects from new X-ray missions coming into operation on a 5-30 year timescale.

The Sloan Digital Sky Survey represents a new paradigm for optical astronomy. It is a consortium involving several hundred astronomers from the US, Japan, and Germany, and aims to obtain basic photometric and spectroscopic data of a large representative region of the high Galactic latitude sky. Using a dedicated wide-field 2.5m telescope and unique instrumentation and software, it is imaging the sky in five photometric bands, and obtaining high-quality spectra of magnitude-limited samples of galaxies and quasars. Many of the exciting scientific results to come from this survey have been a result of follow-up of the intriguing objects found with SDSS on larger and specialized instruments, including Keck, the VLT, and the Hobby-Eberly Telescope. I discuss the synergy between the SDSS and the larger telescopes, with emphasis on studies of high-redshift quasars, and discuss how the SDSS and similar surveys are performing an important role in providing the basis for studies with these larger telescopes.

High redshift radio galaxies are great cosmological tools for pinpointing the most massive objects in the early Universe: massive forming galaxies, active super-massive black holes and proto-clusters. We report on deep narrow-band imaging and spectroscopic observations of several z > 2 radio galaxy fields to investigate the nature of giant Ly-α nebulae centered on the galaxies and to search for over-dense regions around them. We discuss the possible implications for our understanding of the formation and evolution of massive galaxies and galaxy clusters.

We present near-IR long slit spectroscopic data obtained with ISAAC on VLT/ANTU (ESO/Paranal) to produce Bracket gamma and H2 emission line maps and line profile grids of the central 4"×4" region surrounding the central engine of NGC1068. This paper summarizes the results presented in Galliano & Alloin. The seeing quality together with the use of an 0.3" wide slit and 0.3" slit position offsets allow to perform 2D-spectroscopy at 0.5" spatial resolution. The spectral resolution corresponds to 35km s^-1. An asymmetric distribution of H₂ emission is observed: no H₂ emission is detected at the location of the 2.2 μm continuum core, while two conspicuous H₂ knots of are detected at about 1" East and West of the central engine. These knots show a projected velocity difference of 140km s^-1 that we interpreted as the signature of a rotating disk of molecular material. The H₂ emission line profiles appear highly asymmetric with their low velocity wing being systematically more extended than their high velocity wing. A simple way to account for the changes of the H₂ line profiles over the entire 4"×4" region, is to consider that the emission of a radial outflow is superimposed over the emission of the rotating molecular disk. We present a model of such a kinematical configuration and compare our predicted H₂ emission line profiles to the observed ones.

Using ISAAC on VLT-ANTU and UVES on VLT-KUEYEN we have begun a program to measure stellar velocity dispersions of young star clusters in merging and interacting galaxies. In this contribution, we present results for clusters in two interacting galaxies - NGC 4038/39 and NGC 1487. Combining the measured velocity dispersions with sizes of the clusters estimated from Hubble Space Telescope imaging data resulted in the first determinations of dynamical masses of stellar clusters in galaxy mergers. Due to the faintness of the clusters and the high spectral resolution required, these results could only be obtained in with 10m class telescopes. Our results suggest that masses, sizes and concentrations of the light distributions are comparable to those of globular clusters, supporting the idea that part of the globular cluster population in elliptical galaxies is formed as a result of a merger event between to gas-rich spiral galaxies. However, the initial mass function (IMF) of the stars in the clusters seems to vary with environment: In some regions (dust-rich?), the IMF is more biased towards low-mass stars than in other (dust-poor) regions. There is a long-standing and substantial controversy in the literature whether or not their exists a "universal IMF". Our results for clusters in merging galaxies support the notion that the IMF depends on the birth environment of the cluster or perhaps some other variable. The relative content of low mass stars also influences the survival probability of stellar clusters. For their masses and light concentrations, some of the clusters have sufficiently shallow IMFs that it is likely that they will dissolve within a Hubble time, while for others, the IMF is sufficiently steep that they are likely to survive but undergo significant mass loss during their evolution.

We discuss first results from a spectroscopic survey of nuclear star clusters in nearby, late-type spiral galaxies. The data, obtained with the Space Telescope Imaging Spectrograph (STIS), allow us to derive cluster ages via stellar population synthesis methods. We present some typical data sets, describe the fitting algorithm, and discuss the results for the 6 objects studied so far. We find that only one nuclear cluster spectrum is dominated by a population older than 1 Gyr. In all cases, the fit is significantly improved by allowing for multiple generations of stars. Although preliminary, these results support the notion that nuclear cluster formation is most likely a repetitive process.

We present an abundance analysis of six main sequence turnoff, subgiant, and giant branch stars toward the Galactic bulge that were observed with Keck/HIRES during microlensing events. This is an early look at the first detailed chemical analysis of main sequence stars in the Galactic bulge. Lensing events allow the effective aperture of Keck to be increased beyond its current dimensions; although, some events still stretched its spectroscopic capabilities. Future large telescopes with high resolution and high throughput spectrometers will allow the study of abundances in distant stellar populations and in less evolved stars with greater ease.

This paper addresses the problem of measuring dynamical masses, metallicity, dust content and star formation rates of high redshift galaxies using large 8-10m class ground based telescopes and, in particular, the 8m VLT unit telescopes. The theoretical basis of the various methods and their limitations are also briefly reviewed.

In this review, the current (July. 2002) refereed astronomy journals have been surveyed for all AO papers dealing with astronomical science. In the last 9 years, 144 refereed pure science AO papers in solar system, stellar, and extra-galactic astronomy were selected. Of these 144 papers, 28% have been published in the last 18 months. The vast majority of these papers (67%) utilize broad-band near infrared imaging (J, H & K'). More complex techniques (narrowband NIR imaging, L band imaging, AO spectroscopy (2D & 3D), polarimetry, coronography) are becoming robust AO techniques in the NIR (1-2.5 μm). Of less current published success is visible (0.5-1 μm) AO, due in part from the complex technical issues, and also in part from the stiff competition from HST. As well there appears to have been little AO science in the M band. Laser guide stars have surprisingly not yet matured to a point where they enhance the science capabilities of the telescopes that have them. Now that the latest generation of 6-10m AO systems (and their facility AO camera/spectrographs) are finishing the commissioning phases we should see further robust growth in AO science in the immediate future and well into the decade.

For background-limited observations such as those at mid-infrared wavelengths, an increase in telescope aperture not only improves the angular resolution (as it does at all wavelengths) but also leads to very large increases in sensitivity because of the reduced background within the diffraction-limited point spread function. In this presentation we look at the magnitude of that increase for several different operational modes of mid-infrared instrumentation, and we consider some of the implications for science on the current generation of 8-10 meter telescopes.

Since commissioning the near-infrared spectrometer (NIRSPEC) on the Keck II telescope in April 1999 we have been carrying out an extensive spectroscopic survey of low-mass stars and brown dwarfs. At least two objects in every spectral sub-class from M6 to T8 have been observed in the J band at a resolution of R ~ 2,000. For a subset of these we have obtained complete near-infrared flux-calibrated spectra from 0.9 - 2.5 μm. In addition, J band spectra at even higher resolution (R ~ 20,000) have been obtained for many sub-classes. The results of the NIRSPEC Brown Dwarf Spectroscopic Survey (BDSS) are summarized in this paper and presented as an illustration of the progress in infrared technology and the scientific productivity of the Keck telescopes.

There is strong evidence that the planets in the solar system evolved from a disk-shaped solar nebula 4.56 Gyr ago. By studying young stars in various evolutionary stages, one aims at tracing back the early history of the solar system, in particular the timescales for disk survival and for the formation of planetary systems. ISOCAM observations show a steady decrease in the amount of infrared excess from <2 Myr old T Tauri stars to post-T Tauri stars with ages around 10 Myr. The diminished infrared excess can be explained by changes in the global dust opacities due to, e.g., grain growth on timescales of 5 to 15 Myr. In a second program we employed VLT & ISAAC to search for spatially resolved circumstellar disks around young stellar objects (YSOs) in southern star forming regions. The project aimed at establishing a sample suitable for follow-up studies with even higher angular resolution using adaptive optics at the VLT. Two disks seen close to edge-on could be identified. A comparison to HH 30 confirms theoretical predictions that a slight change in the viewing angle of a disk leads to a dramatic difference in the spectral energy distribution of YSOs. This highlights the importance of spatially resolved observations. Finally, we used ISAAC for a near infrared study of the low-mass population in the starburst cluster NGC 3603. The absence of intrinsic infrared excess in the majority of star indicates a paucity of circumstellar disks. Hence extreme environments like starburst clusters might not be fostering the formation of planetary systems.

We report 3-5 μm infrared spectroscopy obtained with VLT-ISAAC on several protostellar jets. Together with H₂ emission lines from the υ=1 rotovibrational state, the spectra show several pure rotational lines of the fundamental state with excitation temperature up to ~22000 K. These observations represent the first detection from the ground of pure rotational (υ=0) H₂ lines in jets. We show how theoretical rotation diagrams indicate these lines as unique both to probe the presence of collisionally excited gas in NLTE conditions and to infer the gas density.

We present AO observations of Io before the satellite went into eclipse, and while it was in Jupiter's shadow. For the sunlit images Io itself was used as the wavefront reference source, while nearby Ganymede was used as reference 'star' when Io was in eclipse. Observations were obtained in Kp, Lp, and Ms bands. We show results before and after deconvolution of the data. We determined the flux densities for the hot spots from the original Io-in-eclipse data via a FFT method, and from the sunlit images after deconvolution of the images with MISTRAL. We present preliminary temperatures and areal coverages for the 6 brightest volcanoes.

Searching for transits provides a very promising technique for finding close-in extra-solar planets. Transiting planets present the advantage of allowing one to determine physical properties such as mass and radius unambiguously. The EXPLORE (EXtra-solar PLanet Occultation REsearch) project is a transit search project carried out using wide-field CCD imaging cameras on 4-m class telescopes, and 8--10m class telescopes for velocity verifications of the photometric candidates. We describe some of the considerations that go into the design of the EXPLORE transit search to maximize the discovery rate and minimize contaminating objects that mimic transiting planets. We show that high precision photometry (2 to 10 millimag) and high time sampling (few minutes) are crucial for sifting out contaminating signatures, such as grazing binaries. We have an efficient data reduction pipeline which allows us to completely reduce the data in less than one month after the imaging observations, allowing us to conduct same-semester velocity follow-up observations, reducing the phase uncertainty. We have completed two searches using the 8k MOSAIC camera at the CTIO4m and the CFH12k camera at CFHT, with runs covering 11 and 16 nights, respectively. Using the 4400 images from the two fields, we obtained light curves for approximately 47,000 stars with better than $\sim1$\% photometric precision. A number of light curves with flat-bottomed eclipses consistent with being produced by transiting planets has been discovered. Preliminary results from follow-up spectroscopic observations using the VLT UVES spectrograph and the Keck HIRES spectrograph obtained for a number of the candidates are presented. Data from four of these can be interpreted consistently as possible planet candidates, although further data are still required for definitive confirmations.

The DEIMOS spectrograph has now been installed on the Keck-II telescope and commissioning is nearly complete. The DEEP2 Redshift Survey, which will take approximately 120 nights at the Keck Observatory over a three year period and has been designed to utilize the power of DEIMOS, began in the summer of 2002. The multiplexing power and high efficiency of DEIMOS enables us to target 1000 faint galaxies per clear night. Our goal is to gather high-quality spectra of ≈ 60,000 galaxies with z>0.75 in order to study the properties and large scale clustering of galaxies at z ≈ 1. The survey will be executed at high spectral resolution, R=λ/Δλ ≈ 5000, allowing us to work between the bright OH sky emission lines and to infer linewidths for many of the target galaxies (for several thousand objects, we will obtain rotation curves as well). The linewidth data will facilitate the execution of the classical redshift-volume cosmological test, which can provide a precision measurement of the equation of state of the Universe. This talk reviews the project, summarizes our science goals and presents some early DEIMOS data.

The Virmos-VLT deep survey (VVDS) is aimed to study the evolution of galaxies, large scale structure and AGNs over more than 90% of the current age of the Universe, based on a large number (more than 100.000) of spectra of galaxies. In a first step, the Vimos Spectrograph will be used to measure all galaxies from magnitude limited samples. In a second step, near IR spectroscopy will be obtained with the Nirmos spectrograph, to measure redshifts in the critical range 1.2AB = 22.5. At the center of one region a deep survey will be conducted for galaxies brighter than I_AB = 24. This deep region has also been imaged at the VLA (1400 MHz) to a flux limit of 0.08 mJy and is being observed in X-Rays with XMM.

Were massive galaxies already in place at high redshift or were they assembled to their total stellar mass only in recent epochs? Trying to quantitatively answer this question is the main goal of the K20 spectroscopic survey that we carried out at the VLT, measuring the redshift of about 500 Ks-selected galaxies. In this paper, we present the first results of this survey and discuss the first constraints on the nature, number density and clustering of EROs, the derivation of the redshift distribution of Ks<20 galaxies and the first results on the evolution of the K_s-band luminosity function. This wealth of observational results is compared to theorethical predictions of semianalytical hierarchical models. The results indicate that, up to z~1-1.5, luminosity evolution provides a satisfactory picture, whereas the strong density evolution required by the current scenarios of hierarchical merging is inconsistent with the observations. The origin of the discrepancy may reside in the incorrect treatment of the baryon assembly, the star formation modes and epoch, and the role of feedback.

We have obtained ultradeep J_s, H and K_s near-infrared imaging of the Hubble Deep Field South WFPC2 field with the ISAAC camera on the VLT. The total integration time of 100 hours resulted in the deepest ground-based infrared observations to date and the deepest K_s-band data ever taken. This depth allows us to determine the spectral energy distributions of the high-redshift galaxies with unprecendented accuracy. Together with existing optical observations, we use the multicolor data to select high-redshift galaxies by their rest-frame optical light, and study their statistical properties and morphologies. We find a wide variety of morphologies: some are large in the rest-frame optical and resemble normal spiral galaxies, others are barely detected in the observers optical and have red NIR colors. The latter belong to a new population of galaxies at redshifts z>2, that is notably absent in the HDF-North. The spectral energy distributions of many of such red galaxies show distinct breaks, which we identify as the balmer break/4000 Angstrom break, and their contribution to the stellar mass density is estimated to be substantial. At redshift z~3, we find a clear excess of superluminious galaxies (> 5 L*_B(z=0)), which is consistent with 1 magnitude of luminosity evolution. Overall, the results show the necessity of deep near-infrared imaging to obtain a full census of the high redshift universe.

An analysis of the galaxy evolution from deep multicolor imaging of optically and infrared selected galaxies is presented and compared with current models of galaxy formation and evolution. A very deep K=20-23) sample of optically and infrared selected galaxies from ESO/VLT and HST surveys like the HDF South, Chandra Deep Field, NTT Deep Field is being analyzed. First results are shown in terms of the high redshift rest frame UV luminosity density and rest frame blue luminosity function and compared with predictions of CDM hierarchical models for galaxy formation and evolution. The observations show an excess of bright sources at very high redshifts 5<z<6 respect to the expectations of the CDM models. At the same time the models predict too many dwarfs especially at intermediate and high redshifts. Possible explanations for these discrepancies are briefly discussed.

In this paper, we show that the determination of the morphological type could be difficult when we observe galaxies in the rest-frame ultraviolet. This could be crucial as soon as we wish to study galaxies at redshifts beyond z~1 since the visible wavelength range corresponds to the rest-frame ultraviolet. In order to address the problem of performing a morphological analysis on a large number of galaxies as the very large samples that will be secured by GALEX, SLOAN, ASTRO-F in the near- to mid-term and from NGST, ALMA and ELT's later on, we need to define a simple quantitative and automatic method. We propose a quantitative multi-wavelength classification that would take into account the various stellar populations lying in the observed galaxies. This method makes use of multi-wavelength data but such databases are already needed to estimate the distance through photometric redshifts. SpectroMorphology allows to perform an automatic analysis of the nature of galaxies.

Encouraged by imaging of faint galaxies around bright stars using ALFA on the 3.5-m telescope at Calar Alto, we have begun a survey to identify a large number of candidate sources near bright stars. In this contribution we report the status of this survey and show our preliminary results from deep imaging around one of these stars during the early phases of CONICA and NAOS on the 8.2-m VLT. We outline the exciting prospects for this type of work in terms of number counts, morphology, and rotation curve analyses.

The present status of weak lensing analyses of clusters of galaxies and of cosmic shear surveys are presented and discussed. We focus on the impact of very large telescopes on present-day and future surveys and compare their potential with HST or wide field 4 meter telescopes.

Studies of the cosmic gamma-ray bursts (GRBs) and their host galaxies are now starting to provide interesting or even unique new insights in observational cosmology. Observed GRB host galaxies have a median magnitude R~25 mag, and show a range of luminosities, morphologies, and star formation rates, with a median redshift z~1. They represent a new way of identifying a population of star-forming galaxies at cosmological redshifts, which is mostly independent of the traditional selection methods. They seem to be broadly similar to the normal field galaxy populations at comparable redshifts and magnitudes, and indicate at most a mild luminosity evolution over the redshift range they probe. Studies of GRB optical afterglows seen in absorption provide a powerful new probe of the ISM in dense, central regions of their host galaxies, which is complementary to the traditional studies using QSO absorption line systems. Some GRB hosts are heavily obscured, and provide a new way to select a population of cosmological sub-mm sources. A census of detected optical tranistents may provide an important new way to constrain the total obscured fraction of star formation over the history of the universe. Finally, detection of GRB afterglows at high redshifts (z>6) may provide a unique way to probe the primordial star formation, massive IMF, early IGM, and chemical enrichment at the end of the cosmic reionization era.

I present science results based on data from the VLT that reflect the quality of the data from this premier observatory, the breadth of the user community and the emerging tremendous impact of the work.

The Inamori-Magellan Areal Camera and Spectrograph is nearing completion. This reimaging spectrograph will have fields of view of 15 arcmin and 27 arcmin in its relecting grating and grism spectrographic modes, respectively, the largest such areas available on one of the new generation of large optical-IR ground-based telescopes. In addition to wide field imaging and a range of low- to medium-resolution spectroscopic modes, IMACS will have a 2 × 1000 fiber-fed integral field unit built by Durham University, an ecellette mode, and the potential for a full-field tunable filter. We review some of the planned science programs for IMACS, ranging from spectroscopy of stars in the Galactic halo and nearby dwarf spheroidal galaxies, the search for stars between galaxies, internal kinematics in normal galaxies and AGN, and the evolution of high redshift galaxies and galaxy clusters.

This paper describes the science drivers and first generation instrumentation capabilities of the Southern African Large Telescope (SALT), due to begin science operations in late 2004/early 2005. First generation instruments are confined to the visible spectrum, but optimized for UV performance, with capability to ~320 nm. Instrumentation will have access to a circular 8 arcmin diameter science field, with guidance objects outside of this region (< 5 arcmin off-axis). Although SALT will have active mirror control to optimize image quality, the mirror array will not be phased (in it's first light configuration), so adaptive optics is not planned initially and instruments will be optimized to the median seeing conditions (0.9 arcsec FWHM). The telescope design, based on the Hobby-Eberly Telescope (HET), also necessitates a queue-scheduled observing approach, which is ideal for time resolved studies of astrophysical phenomena on timescales of >days. Time resolved studies are an important aspect of the overall SALT science drivers. Special efforts are being made to ensure high time resolution capability by employing frame transfer CCDs on two of the first-light instruments, the imaging spectrograph (PFIS/IMPALAS) and imaging camera (SALTICAM). Time resolutions of ~50 ms for spectroscopy, with zero dead-time, are planned. Instrument capabilities, which include polarimetry, Fabry-Perot imaging spectroscopy and high resolution fibre-fed spectroscopy (HRS/CELESTIA), will ensure that the major science goals of SALT's partners are realized.

The Very Energetic Radiation Imaging Telescope Array System (VERITAS) is an array of seven 10m aperture telescopes used for gamma-ray astronomy in the 50 GeV to 50 TeV (1 TeV= 10¹² electron Volt) energy range. The gamma rays are detected by measuring the optical Cherenkov light emitted by the cascade of electromagnetic particles that is generated by interactions of the high energy gamma-ray with the Earth's Atmosphere. This paper describes the science goals of the VERITAS array, a description of the array, and expected performance of the instrument.

The 8.2m Subaru Telescope had its astronomical first light at the Cassegrain focus in January 1999. The partial open use of the instruments started since December 2000. Currently, all the seven instruments are offered for open use and observational proposals are reviewed by the Time Allocation Committee of the Subaru Advisory Committee for each semester. The average competition rate is 6-7 times over the last four semesters. Up to the present, about 60 scientific papers have been published in refereed journals reporting scientific results based on observations of the Subaru Telescope. Described in this overview talk is a brief summary of some remarkable results mainly on extragalactic astronomy. The topics reported include near infrared galaxy number count, luminosity functions and clustering of Lyman break galaxies, high-z Lyman α emitting galaxy, population study of clusters of galaxies, gravitational lensing of clusters, properties of extremely red objects, studies on gravitational lensed quasar images and quasar absorption lines, a hypernova, metal poor stars, planet harboring stars, and issues on other specific objects. The preliminary progress reports on the Subaru Deep Field Survey and the supernovae survey are also given.

The host galaxies of powerful radio sources are ideal laboratories to study active galactic nuclei (AGN). The galaxies themselves are among the most massive systems in the universe, and are believed to harbor supermassive black holes (SMBH). If large galaxies are formed in a hierarchical way by multiple merger events, radio galaxies at low redshift represent the end-products of this process. However, it is not clear why some of these massive ellipticals have associated radio emission, while others do not. Both are thought to contain SMBHs, with masses proportional to the total luminous mass in the bulge. It either implies every SMBH has recurrent radio-loud phases, and the radio-quiet galaxies happen to be in the "low" state, or that the radio galaxy nuclei are physically different from radio-quiet ones, i.e. by having a more massive SMBH for a given bulge mass. Here we present the first results from our adaptive optics imaging and spectroscopy pilot program on three nearby powerful radio galaxies. Initiating a larger, more systematic AO survey of radio galaxies (preferentially with Laser Guide Star equipped AO systems) has the potential of furthering our understanding of the physical properties of radio sources, their triggering, and their subsequent evolution.

The Keck II Adaptive Optics system and the NIRC2 camera provide a unique facility for high angular resolution imaging and spectroscopy in the near infrared. In this paper, we present the result of a unique project to map the entire surface of Io in the thermal infrared (Lp band centered at 3.8 μm). This project was undertaken by a team from the W. M. Keck Observatory and UC Berkeley to illustrate the power of this instrumentation. The 75-milliarcsec-resolution images, corresponding to ~200 km of linear spatial resolution on Io, have been combined to build a thermal infrared map of the entire satellite. We have identified 26 hot spots including one that was undetected by the Galileo mission. A movie and a Java applet featuring a volcanically active rotating satellite were created.

We conducted deep NIR and optical imaging observations in general fields as well as the fields of cluster of galaxies and candidates at z > 1. In the observed rich cluster environment, massive galaxies have been well developed by z=1.2-1.3. However, in a general field, HDF-N, we see conspicuous and sudden decrease of comoving number density of early-type galaxies above z=1. There are few galaxies as massive as present-day L* galaxies at z=2-4 in HDF-N. Their rest-frame optical light is dominated by very young stellar population and their morphology also does not show any clear sequence. Thus formation/evolution of galaxies seems to strongly depend on their density environment and in general fields massive galaxies which form present-day Hubble sequence might have been formed between 1 < z < 2 while early type galaxies in clusters formed earlier epoch.

The high optical quality of ESO's ISAAC instrument at the 8.2-m ANTU VLT telescope and the good observing conditions at the Paranal site allow very detailed studies of southern massive star-forming regions. Our observations revealed their large degree of complexity. By means of near- and thermal-infrared images we performed a thorough characterisation of the embedded stellar population. Imaging polarimetry provided clues on the spatial distribution of the dust grains and the illuminating sources. Special emphasis was put on the most massive objects, young luminous stars that cause ultracompact HII regions.

High-z galaxies beyond redshift ~ 4 are essentially detected from ground based observations through their Lyα emission. The anticipated Lyα flux of galaxies at redshifts ~ 6 and beyond is a few times 0.1 10^-17 ergs.s^-1.cm^-2 and its detection requires observations in low background conditions, when the observing wavelength is pushed into the near IR domain. We have carried out observations on 4-8 m telescopes to search for high z galaxies at 920 nm, 1060 and 1187 nm, resorting to various techniques: Narrow Band (NB) imaging and multi-slit windows. Observations, data reduction and preliminary results are described.

Phoenix, a high resolution near-infrared spectrograph build by NOAO, was first used on the Gemini South telescope in December 2001. Previously on the Kitt Peak 2.1 and 4 meter telescopes, Phoenix received a new detector, as well as modified refrigeration, mounting, and handling equipment, prior to being sent to Gemini South. Using a two-pixel slit the resolution is ~75,000, making Phoenix the highest resolution infrared spectrograph available on a 6-10 meter class telescope at the current time. Modifications to and performance of the instrument are discussed. Some results on Magellanic cloud stars, brown dwarf stars, premain-sequence objects, and stellar exotica are reviewed briefly.

The Hubble Space Telescope (HST) has produced dramatic images of proto-planetary disks (“proplyds”) surrounding your (<10⁶ year old) stars embedded in the Orion Nebula. The intense UV radiation field of the high-mass Trapezium stars heats the disk surfaces, drives mass-loss, and produces bright ionization fronts. Many disks are seen in silhouette against the nebular background of the Orion Nebula, or against the proplyd’s own ionization front. The sub-arcsecond resolution and light gathering power of the Keck telescopes in the near-IR provide a unique opportunity to study the earliest phases of planetary disk evolution and disk destruction under intense UV radiation fields. We present initial results from observations of a handful of proplyds using KCAM and NIRSPEC, with and without the adaptive optics (AO) system, on Keck II. These data clearly resolve, both spatially and spectrally, ionization fronts, disks, and a microjet. The data are used to constrain mass-loss rates due to photoevaporation, disk surface wind velocity, and grain size distribution.

The Texas-Oxford One Thousand (TOOT) radio source redshift survey is aimed at understanding the evolution of the radio source population down to flux density of S_151MHz = 100 mJy. This low frequency survey has a depth equivalent to about five times the NVSS limit, but does not contain the population of star forming galaxies detected in the NVSS survey. In addition, the survey reaches a high enough surface density of sources on the sky to probe large-scale structure at z ~ 1. Radio sources inhabit massive elliptical galaxies, and as such provide excellent sparse tracers of large-scale structure that are both easily identified and easily observed with spectrographs to map out their space distribution. We review the properties of the TOOT survey and its current status. We also report the discovery, using radio sources, of a huge structure at z=0.27 traced by radio sources and galaxy clusters. Such superstructures are aggregates of clusters seeded by rare (> 3σ) peaks in the power spectrum at recombination. The radio sources and galaxy clusters are shown to trace the same matter distribution. This is the first demonstration of radio AGN as direct sparse tracers of the underlying dark matter distribution. The extent of the superstructure is of order 100 h^-1 Mpc in three dimensions, making it the largest structure known, and indicating a mass similar to that of the Great Attractor. We report the properties of the superstructure, and consider the implications of its existence.

Since April 2001 a Large Program for the study of physical properties of Trans-Neptunian Objects (TNO) and Centaurs is underway at the Paranal (Very Large Telescope VLT) and La Silla (New Technology Telescope NTT) observatories of the European Southern Observatory (ESO) in Chile. Combining service (SM) and visitor mode (VM) observations multi-wavelength imaging (BVRIJHK filters) and low-dispersion spectroscopy is performed in the visible and near-IR on a sample of objects that should allow a better and more consistent taxonomic characterization and classification of these pristine bodies in our solar system. Starting with a summary of the current knowledge on the Kuiper-Belt and the populations of objects, the paper presents the goals of this project and its scientific and organizational implementation. It illustrates the progress and the scientific achievements by a hynoptic view of results from photometry and spectroscopy of these Solar System objects.