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Five decades ago, astronomers finally broke free of the boundaries of light when a new science, radio astronomy, was born. This new way of ‘seeing’ rapidly uncovered a range of unexpected objects in the cosmos. This was our first view of the non-thermal universe, and our first un obscured view of the universe. In its short life, radio astronomy has had an unequaled record of discovery, including four Nobel prizes: Big-Bang radiation, neutron stars, aperture synthesis and gravitational radiation. New technologies now make it possible to construct new and upgraded radio wavelength arrays which will provide a powerful new generation of facilities. Radio telescopes such as SKA and the upgraded VLA will have orders of magnitude greater sensitivity than existing facilities. They will be able to study thermal and non-thermal emission from a wide range of astrophysical phenomena throughout the universe as well as greatly extending the range of unique science accessible at radio wavelengths.

Several projects and studies are being prepared for the second decade of the third millennium, both in space and on the ground. Here we review the status of optical / near infrared facilities now on the drawing board, with particular emphasis on the (JWST), the (TMT), and the 100m telescope (OWL).

This report describes the new 40-meter radiotelescope which is currently close to the end of its construction phase at Yebes, near Guadalajara, Spain.

A second generation space VLBI mission, VSOP-2, is being planned for a launch in 2010 or soon after. The scientific objectives are very high angular resolution imaging of astrophysically exotic regions, including the cores, jets, and accretion disks of active galactic nuclei (AGN), water maser emissions, micro-quasars, coronae of young stellar objects, etc. A highest angular resolution of about 40 as is achieved in the 43 GHz band. Engineering developments are in progress for the deployable antenna, high data rate transmission, cryogenic receivers, antenna pointing, accurate orbit determination, etc., to realize this mission. International collaboration will be as important as it has been for VSOP.

SKA will be operating at the same time with several new large optical, X–ray and Γ–ray facilities currently under construction or planned. Fostering synergies in astrophysical research made across different spectral bands presents a compelling argument for designing the SKA such that it would offer imaging capabilities similar to those of other future telescopes. Imaging capabilities of the SKA are compared here with those of the major future astrophysical facilities.

Korean VLBI Network (KVN) is a mm-VLBI network construction project of Korea Astronomy Observatory. During the (first) project period (2001 - 2007), three observatories are going to be constructed at Seoul (Yonsei Univ.), Ulsan (Univ. of Ulsan), and Jeju (Tamna Univ.). All possible baselines and the sites of the observatories are listed in Table 1. Scientific goals are various, e.g. continuum observation of AGNs, of star forming regions, of microquasars, spectroscopy of stars, of star forming regions, and of Galactic centre region as well as geodetic observation. The antenna specifications of KVN are described in Table 2.

The electromagnetic (radio) spectrum is a very valuable natural resource that is finite and shared by an increasing number of users vying for the allocation of frequency bands. As a result, the electromagnetic environment in which astronomical observations are made is getting increasingly polluted, driven by commercial interests. In general, non-scientific spectrum use emits radiation at levels that far exceed those emitted by the cosmic sources in which astronomers are interested.

We describe the capabilities of SCUBA-2, the first CCD-like imager for submillimeter astronomy, and the technologies that make it possible. Unlike previous detectors using discrete bolometers, SCUBA-2 has two dc-coupled, monolithic arrays with a total of ~10,000 bolometers. SCUBA-2’s absorber-coupled pixels use superconducting transition edge sensors operating at ~ 120mK for photon-noise limited performance and a SQUID time-domain multiplexer for readout. It will offer simultaneous imaging of an 8 × 8 arcmin field of view at wavelengths of 850 μm and 450 μm. SCUBA-2 is expected to have a huge impact on the study of galaxy formation and evolution in the early Universe as well as star and planet formation in our own Galaxy. Mapping the sky to the same S/N up to 1000 times faster than SCUBA, SCUBA-2 will also act as a pathfinder for submillimeter interferometers such as ALMA. SCUBA-2 will begin operation on the JCMT in 2006.

The LMT is a 50m–diameter millimeter-wave antenna designed for performance in the 1–4mm band. Erection is expected to be completed by the end of 2004, with outfitting running through 2006. The LMT will have nearly 2000m of collecting area with an overall surface accuracy of 70 μm rms. Its sensitivity will exceed that of existing millimeter–wavelength telescopes by a significant margin. As a completely filled aperture, the LMT will have optimum sensitivity to low surface brightness emission at angular resolutions of 6–15 arcsec, which is comparable to that of maps made with today’s interferometric arrays. Consequently, we expect the LMT to become one of the premier instruments to explore the cosmic frontier.

The Submillimeter Array (SMA) is a new interferometer dedicated to observations in millimeter and sub-millimeter wavelengths. It is located on Mauna Kea, Hawaii, near the CSO and JCMT facilities and was commissioned in November 2003 [2]. The array consists of eight 6-meter diameter antennas which can be moved among 24 pads on the sides of four Reuleaux triangles, producing a maximum angular resolution of 0″.1. Each antenna is equipped with a cryostat at its Nasmyth focus which will accept eight receivers covering all usable bands from 175 GHz to 920 GHz. Signal processing is performed on a special purpose XF correlator, which is based on an ASIC developed at the Haystack Observatory and the NASA/SERC for VLSI Design. The highly flexible correlator will accept two channels of 2 GHz bandwidth from each antenna, making possible either dual polarization or simultaneous dual frequency operation. A pilot program to include the 15m JCMT and 10.4m CSO as part of the SMA will begin in 2005.