IAA award to VSOP team

The International Academy of Astronautics (IAA) has awarded its Laurels for Team Achievement Award for 2005 to the VLBI (Very Long Baseline Interferometry) Space Observatory Programme (VSOP) Team. The Award, presented on 16 October at the 56th International Astronautical Congress in Fukuoka, Japan, was made to an international group of 15 scientists and engineers including the ATNF's David Jauncey.

Australian involvement in space VLBI goes back almost 20 years to the TDRSS (Tracking and Data Relay Satellite System) experiments first conducted in 1986 with a geostationary TDRSS satellite, the Usuda 64-m telescope in Japan and the Tidbinbilla 64-m telescope (as it was then). These were the first successful space-to-ground VLBI observations ever undertaken (Levy, G.S. et al. 1986, Science, 234, 187). The links with Japan were strengthened during the first Space VLBI Work Week, held at Epping in April 1991. It was at this meeting that the first steps were made by radio astronomers from Australia and Japan toward an Asia-Pacific VLBI network, which led to the establishment of the Asia-Pacific Telescope (APT, www.vsop.jaxa.jp/apt/ ), providing a boost for regional VLBI collaboration and a vehicle through which the regional telescopes were able to contribute to the mission.

The radio astronomy satellite HALCA carrying an 8-m radio telescope was launched from Kagoshima by Japan's Institute of Space and Astronautical Science (ISAS) on 12 February 1997 to participate in VLBI observations with arrays of ground radio telescopes across the world. Radio telescopes from 14 countries contributed observing time to the VSOP mission, and in turn VSOP observing time was open to peer-reviewed proposals from astronomers all around the world. Five dedicated tracking stations, one at Tidbinbilla, one in Japan, two in the USA, and one in Spain, provided the critical real-time two-way link to HALCA, uplinking the LO phase (suitably Doppler shifted to take into account the satellite's motion), and receiving the satellite's digitized VLBI data-stream at 128 mega-bits per second. Three correlators, in Japan, the USA, and Canada, and two orbit determination teams, in Japan and the USA, rounded out the mission.

Australia is the principal radio astronomy nation in the southern hemisphere and our telescopes at Ceduna, Hobart, Parkes, Mopra, Narrabri and Tidbinbilla, have made a major contribution to VSOP. The involvement of Australian scientists was described in Richard Dodson's article in the previous issue of the ATNF News. Mopra has the distinction of participating in 25% of all VSOP observations! VSOP is arguably the most sophisticated and complex space science mission to date in terms of the variety and complexity of its globally distributed resources and the amount of data transmitted from a scientific spacecraft to the Earth.

Simultaneous observations with HALCA's 8-m diameter radio telescope and arrays of ground radio telescopes synthesize a radio telescope almost three times the size of the Earth, enabling the highest angular resolution 1.6-GHz and 5-GHz images to be made. The role of coordinating all ground and space elements was carried out by the small but dedicated team at ISAS (now part of the Japan Aerospace Exploration Agency, JAXA) and the National Astronomical Observatory of Japan (NAOJ).

HALCA has participated in over 780 VSOP observations, predominantly of the cores and relativistic jets in active galactic nuclei. Two-thirds of HALCA's observations have been made for observing projects selected by international peer-review from proposals submitted by the astronomical community in response to Announcements of Opportunity. The remainder have been devoted to a mission-led all-sky survey of active galactic nuclei at 5 GHz the VSOP Survey Program.

The IAA citation notes that the technique of Very Long Baseline Interferometry has enabled the longest astronomical wavelengths to be used to produce the highest angular resolution images. VSOP realized the long-held dream of radio-astronomers to extend those baselines into space, by observing celestial radio sources with the HALCA satellite, supported by a dedicated network of tracking stations, and arrays of ground radio telescopes from around the world. On behalf of the entire VSOP Team the award highlighted the astronomers and engineers who made key contributions to realizing, and operating, a radio telescope bigger than the Earth: Hisashi Hirabayashi (ISAS/JAXA), Haruto Hirosawa (ISAS/JAXA), Peter Dewdney (DRAO, Canada), Edward Fomalont (NRAO, USA), Leonid Gurvits (JIVE, The Netherlands), Makoto Inoue (NAOJ), David Jauncey (ATNF), Noriyuki Kawaguchi (NAOJ), Hideyuki Kobayashi (NAOJ), Kazuo Miyoshi (Mitsubishi Electric Corporation, Japan), Yasuhiro Murata (ISAS/JAXA), Takeshi Orii (NEC, Japan), Robert Preston (JPL, USA), Jonathan Romney (NRAO, USA), and Joel Smith (JPL, USA).

The Laurels for Team Achievement Award was created by the International Academy of Astronautics in 2001 to recognize extraordinary performance and achievement by a team of scientists, engineers and managers in the field of Astronautics. The previous recipients are the Russian Mir Space Station Team (2001), the US Space Shuttle Team (2002), the Solar and Heliospheric Observatory (SOHO) Team (2003), and the Hubble Space Telescope Team (2004).

The VSOP mission is nearing its end. However, having received their Laurels, the VSOP team are not resting on them! Planning for a next generation mission, currently dubbed VSOP-2, is well underway. The formal VSOP-2 proposal was one of three submitted to ISAS/JAXA in September, with the successful mission being decided early next year. VSOP-2 will provide ten times better angular resolution and ten times better sensitivity than VSOP, indicating a bright future for space VLBI.

The International Academy of Astronautics was founded in August 1960 in Stockholm, Sweden, during the 11th International Astronautical Congress. The Academy aims to foster the development of astronautics for peaceful purposes; recognize individuals who have distinguished themselves in a related branch of science or technology; provide a program through which members may contribute to international endeavours; and foster cooperation in the advancement of aerospace science.

Phil Edwards and Dave Jauncey
(pge@vsop.isas.jaxa.jp and David.Jauncey@csiro.au)