Onsala Space Observatory – IVS Network Station Activities during 2015–2016 (original) (raw)

Onsala Space Observatory – IVS Analysis Center Activities during 2013

2014

This report briefly summarizes the activities of the IVS Analysis Center at the Onsala Space Observatory during 2013 and gives examples of results of ongoing work. 1 General Information We concentrate on research topics that are relevant for space geodesy and geosciences. These research topics are related to data observed with geodetic VLBI and complementing techniques.

Onsala Space Observatory – IVS Analysis Center Activities during 2014

2015

This report briefly summarizes the activities of the IVS Analysis Center at the Onsala Space Observatory during 2014 and gives examples of results of ongoing work. 1 General Information We concentrate on research topics that are relevant for space geodesy and geosciences. These research topics are related to data observed with geodetic VLBI and complementing techniques.

Onsala Space Observatory – IVS Network Station Activities During 2013

2014

We participated in 40 IVS sessions. As in the previous five years, we used several of the sessions that involved both Onsala and Tsukuba to perform ultra-rapid UT1-UTC observations together with our colleagues in Tsukuba. Additionally, we observed two dedicated ultra-rapid sessions. The first was together with Tsukuba, Hobart, and HartRAO and aimed at determining ultra-rapid EOP. The second was together with Tsukuba and aimed at a northern hemisphere ultra-rapid UT1-UTC determination in parallel with the AUST-13-06 session. We also performed a short session in which we observed a GLONASS satellite using the Onsala 25-m telescope and the Wettzell 20-m telescope. The progress of the Onsala Twin Telescope (OTT) project was unfortunately delayed due to issues concerning wildlife protection. Extensive OTT simulation studies were performed, trying to optimize the sky visibility from a number of possible antenna locations. An updated application for the installation was submitted to the authorities at the end of 2013.

Onsala Space Observatory – IVS Network Station Activities during 2014

2015

We participated in 39 IVS sessions, including CONT14. Eleven out of the initially planned sessions could not be observed due to the installation of a new radome for the 20-m radio telescope. As in the previous six years, we used several of the sessions that involved both Onsala and Tsukuba to perform ultrarapid UT1-UTC sessions together with our colleagues in Tsukuba. This included the complete CONT14 campaign where near real-time UT1-UTC on the baseline Onsala-Tsukuba could be determined. The procurement of the telescopes for the Onsala Twin Telescopes was started in the summer of 2014. The contract to buy two VGOS radio telescopes was signed at the end of the year.

Onsala Space Observatory – IVS Technology Development Center Activities during 2013

2014

We give a brief overview on the technical development related to geodetic VLBI done during 2013 at Onsala Space Observatory. 1 Activities during 2013 Our activities in technical development for VLBI concentrated on the following topics: • The Onsala Twin Telescope project • Broadband feeds for VLBI2010 operations • A dual-polarized S-band system • A new IF distribution • A GNSS installation for local-tie measurements. 2 The Onsala Twin Telescope Project We worked on the preparation of the procurement documents for the Onsala Twin Telescope (OTT). We decided to separate the procurement into two parts. One part exclusively covers the antennas while the other part covers the signal chain and electronics. The request for a building permit for the OTT and the request for an exemption from the law for shoreline protection (i.e., a permit for construction within 300 m from the shoreline) had been submitted to the Kungsbacka municipality already in late 2012. The local au1. Chalmers Univers...

Twin Telescopes at Onsala and Wettzell and their contribution to the VGOS System

2015

During the last years the International VLBI Service for Geodesy and Astrometry (IVS) spent efforts to improve the accuracy of the geodetic Very Long Baseline Interferometry (VLBI) system to 1 mm for station positions and 0.1 mm/yr for station velocities. To achieve these ambitious goals the VLBI2010 Global Observing System (VGOS) concept was developed, which includes broadband observations with fast-slewing antennas and suggests twin telescopes to reduce the source switching interval and increase the number of observations. Wettzell in Germany has already installed a twin telescope and further twin telescopes will be built in the coming years at Onsala (Sweden) and Ny-Alesund (Spitsbergen, Norway). In this study, the Vienna VLBI Software (VieVS) is used to schedule and simulate a global VLBI network using the sites that participated in the CONT11 campaign. We compare schedules using the legacy telescopes at Onsala and Wettzell with schedules where either one or both legacy telescop...

Contributions of Onsala Space Observatory to GGOS

2015

The Onsala Space Observatory (OSO) on the Swedish west coast is the fundamental geodetic station of Sweden and operates several co-located geodetic and geophysical infrastructures that contribute to the GGOS. Currently, work is ongoing to establish a twin telescope to be part of the VGOS network.