NEWS
Inspection of the Vienna Scientific Cluster 4
Jakob, Jamie and Johannes used the chance and visited the Vienna Scientific Cluster 4 (VSC-4) where we will use 10 private nodes for VLBI correlation. We are still waiting for the storage to get started.
Bachelor presentation Markus Mikschi
On September 10, 2019, Markus Mikschi presented his bachelor thesis on the integration of length-of-day values for the determination of UT1. Depending on the calibration, it is possible to achieve an accuracy of 40 microseconds after a week. It should also be noted here, that his presentation was the last one in our “old meeting room” with all things prepared for the move to Freihaus.
DiFX-2.6 released
A new stable major version of DiFX: DiFX-2.6.1 has been released.
The source code can be obtained via SVN at: https://svn.atnf.csiro.au/difx/master_tags/DiFX-2.6.1 .
Documentation can be found at the DiFX Wiki: https://www.atnf.csiro.au/vlbi/dokuwiki/doku.php/difx/start
Visit by colleagues from Beijing Aerospace Control Center
On 22 August 2019, four colleagues from the Beijing Aerospace Control Center (BACC) visited us at TU Wien to inform each other about research focus points and to discuss possible future co-operation activities.
VSC-4 powered on
In June 2019, the Vienna Scientific Cluster 4 was powered on. This is very good news, because we will have 10 private nodes (480 cores in total) and 1 PByte of storage for correlation activities. Also the Standard (Austrian newspaper) reports about VSC4.
Paper on VieSched++ published
A paper on “VieSched++: A New VLBI Scheduling Software for Geodesy and Astrometry” by Schartner and Böhm was published in the Publications of the Astronomical Society of the Pacific. It will serve as reference for the new scheduling software.
The ICRF3 is here
The ICRF3 is the most recent realization of the ICRS and was calculated by an IAU working group consisting of resea
rchers from all over the world. The Vienna VLBI Center was an active part of this group with Johannes Böhm as an working group member and David Mayer as an PhD student working on this topic. The ICRF3 was finished in 2018 and was approved by the IAU as the new standard celestial reference frame.
More than 4500 sources are listed in the ICRF3. For the first time it is a multi wavelength catalog with most of the positions in X/S band and some in higher frequency bands (K and X/Ka). The noise level of this catalog is 30 µas which is equivalent to seeing a tennis ball on the surface of the moon. At such a level of accuracy even tiny effects can distort positions and therefore have to be modeled. A tiny effect which was not modeled in the ICRF2 but was modeled in the ICRF3 is the so called galactic aberration which is an effect from the rotation of our solar system about the galactic center.
The ICRF3 is freely available and can be downloaded from this link. A Vienna only solution of this reference frame can be found in our products section.