MINUTES

 

of the RadioAstron Teleconference 2
April 4, 2003

Willem Baan chaired the teleconference.

The agenda of the teleconference and the list of participants are attached as an Appendix A to the Minutes, and list of used acronyms and conventional names is given as an Appendix B.

 

The main purpose of the teleconference was to review the progress on the RadioAstron project during the first quarter of 2003.

 

The following conclusions and action items were developed as a result of the discussions:

 

1. Kardashev informed the participants about the technical progress in the development project. He specified the following achievements:

1.1. Technical documentation for the thermo‑vacuum tests (TVT) of the spacecraft and the SRT device module was written. Preparations are made for the TVT.

1.2. The Focal Container (hardware) and the cables are prepared at LA for assembly into the Electronic Complex (engineering models), which will be delivered to LA from ASC.

1.3. Geometrical adjustment of the antenna petals is continued at LA using the "adjusting points" technique.

1.4. The SRT assembly of the special configuration for the Pushchino tests was started at LA.

1.5. The checkout of the Focal Container electronics (Electronic Module) is being done at ASC before delivery to LA.

1.6. Determination of the SNR at the correlator output for different parameters of the Zero Base Interferometer has been done at ASC.

1.7. Technical documentation, necessary for the input checkout and the assembly at LA of the engineering models of the scientific payload for future Pushchino tests, was written at ASC.

 

2. Kardashev informed the participants about the time-line for the project development in 2003. He ensured the participants that the funding necessary for project development in 2003 is anticipated to be provided in full. He emphasized that the following tasks need to be completed in 2003:

2.1. Thermo-vacuum tests of the Spacecraft Bus and the SRT Device Module together with the cooling system of the LNAs.

2.2. Manufacturing of the transportation bus for SRT shipment to Pushchino. (LA, July).

2.3. SRT antenna reflector mounting and assembly for the Puschino tests. (LA, April - July).

2.4. Preparation, delivery and input checkout of the Electronic Complex (and documentation) for SRT assembly together with antenna and mechanisms. (ASC/LA, May - June).

2.5. Preparation and delivery of SRT Test Sets and the SRT tests after assembly at LA. Transportation to Puschino. (ASC/LA, July - August).

2.6. Preparation of Puschino Polygon (test facilities) and ground-based equipment. (ASC, June - July).

2.7. Assembly, mounting, checkout and tests of Engineering Model of the SRT in Puschino. (ASC, August - October).

2.8. Modernization of the SC bus equipment (TMS, radio channel, computer). (LA,March - December).

 

The Chairman suggested that ASC distribute monthly e-mail reports on the various activities in the RadioAstron project in order to keep all RISC members and telecon participants informed on the progress.

 

 

3. Kardashev provided clarification concerning the Technical Task TZ document, which is equivalent to the NASA designation of Project Plan. The document was distributed before the teleconference in raw translation into English. The document has been approved by the Director of ASC (Kardashev) and by the Director General of LA (Kulikov), but it has not yet been approved by the President of Russian Academy of Science and by Director General of Russian Aviation-Space Agency. The reason for this is the uncertainty about two main items, which are the on-board H-maser frequency standard and the configuration of tracking stations. The Technical Task (TZ) document does not treat the international collaboration in the Mission and these aspects of the mission will have to be described in separate agreements between the participating institutions.

 

4. A complex discussion followed on the advisability of implementing an on-board H-maser frequency standard. On the one hand, the H-maser has been included in the on-board science payload according to item 6.1.8. of the TZ and only a well-argued formal decision would be needed to eliminate it. On the other hand, there are strong doubts whether the manufacture and delivery of an H-maser will be possible in the given time limit and within the available funds (Gurvits). There was also the opinion expressed by Kellermann that the on-board H-maser is not a crucial element for the mission and may be treated as a supplementary non-essential device.

In response to this discussion, Kardashev informed the participants that a Memorandum on the advantages of implementing an on-board H-maser and an ultra-sensitive accelerometer is under development at the ASC. The most important question is to understand the influence of an H-maser on the maximum integration time and the sensitivity. The Memorandum will naturally include a comparison of mission parameters that will be achieved with and without the H-maser and the accelerometer. Kardashev invited foreign assistance in the development of this Memorandum, especially from those having experience with the VSOP mission. The Memorandum is planned before the next teleconference in the middle of June.

 

5. Baan raised the issue of tracking stations and particularly the status of development of Pushchino tracking station. Kardashev responded that necessary technical documentation for the instrumentation of Pushchino tracking station were prepared at ASC, but that no implementation has been started yet, because the ASC is waiting for the NASA response on a request to transfer some hardware from other NASA tracking stations. Mark Allen commented on this that earlier this year the Astrophysics Advisory Committee considered NASA participation in RadioAstron, and that its report was submitted to the Space Science Advisory Committee in March. A decision will be available in a few weeks. Kardashev emphasized that the operation of the Mission with Puschino as only tracking station would reduce the efficiency to about 30%. In order to have a higher efficiency, the Mission needs two extra tracking stations: one in the western hemisphere and one in the southern hemisphere (Green Bank and Tidbinbilla).

 

6. Popov reported on the current RISC membership. The following list presents the current status; the first line is the addressee whom the ASC sent the request, and the nominated member is indicated in the every second line below:

 

 

David Southwood, ESA, France,

Kornelis Van Klooster

 

Ron Ekers, ATNF, Epping, Australia

David Jauncey

 

Phil Diamond, EVN, Jodrell Bank, UK

Phil Diamond (Willem Baan), Leonid Gurvits

 

Hiroki Matsuo, ISAS, Sagamihara, Japan

Hisashi Hirabayashi

 

Anssi Malkki, FMI, Helsinki, Finland

Seppo Urpo

 

Zhao Junliang, ShAO, Shanghai, China

Xiaoyo Hong

 

Alain Maurissen, Neuchatel Observatory, Switzerland

Alain Maurissen

 

Leonid Lytvyenko, IRA, Kharkov, Ukraine

Leonid Lytvyenko

 

Anton Zensus, MPIfR, Bonn, Germany

Anton Zensus

 

Rajaram Nityananda, NCRA, TIFR, Pune, India

S.Anathakrishnan

 

Bernard Burke, MIT, Cambridge, USA

Bernard Burke

 

No request was sent to Canada because ASC is waiting for a reaction from the Canadian Space Agency on the letter sent from the Russian Aviation and Space Agency with a proposal to participate in the RadioAstron project.

 

No response has been received from the following addressees:

Fred K.Y. Lo, NRAO, Charlottesville, USA

Marc S. Allen, NASA, Washington, USA

Gianni Tofani, IRA, Bologna, Italy

Daniel Altschuler, Chris Saulter, Arecibo Observatory, NAIC, USA

Norbert Bartel, York University, Toronto, Canada

 

7. Popov informed the participants that comments on the Terms of Reference (version 3 from December 10 2002) are invited. The document will be present for approval at the next RadioAstron meeting in Moscow in November 2003.

 

8. The date for the next RadioAstron meeting was set for November 10-12, 2003.

 

9. The next teleconference is planned for July 3, 2003.

 

10. Action Items resulting from the discussions:

April03-1. Memorandum on the advisability of implementation of the on-board H-maser and ultra-sensitive accelerometer to be prepared by ASC before telecon in June 2003.

April03-2. Monthly reports on the main achievements in project development will be distributed by ASC at the end of every months starting from April 2003.

April03-3. Chairmen of the Working Groups are urged to submit a Plan of Activities of the Working Groups for discussion at the next teleconference.

 



Appendix A

 

Agenda for the Teleconference on RadioAstron on April 4 2003.

 

1. Sound check and attendance.

2. Review and corrections of the telecon agenda - Chairman

3. Technical progress and time-line for 2003 - N.Kardashev

3.1. Technical Task document (TZ)

3.2. Spacecraft Bus

3.3. Science Payload

3.4. Tracking Stations

4. New RISC members - M.Popov.

5. Status of the development of the Terms of Reference - M.Popov

6. To set the date of the next RadioAstron meeting (Moscow, 3-5 November 2003).

7. Suggested date for the next teleconference June 26 2003.

 


List of participants

1. Allen M. NASA, USA

2. Altunin V.I., JPL NASA, USA

3. Andreyanov V., ASC, Russia

4. Baan W.A., ASTRON, The Netherlands

5. Babakin N., ASC, Russia

6. Babyshkin V.E., LA, Russia

7. Bartel N., York University, Canada

8. Belousov K., ASC, Russia

9. Burke B., MIT, USA

10. Cannon W., CRESTech, Canada

11. D'Addario L., NRAO, USA

12. Fomalont E., NRAO, USA

13. Gurvits L., JIVE, The Netherlands

14. Hayes J., NASA, USA

15. Van't Klooster K., ESA, The Netherlands

16. Kanevsky B., ASC, Russia

17. Kardashev N.S., ASC, Russia

18. Kellermann K., NRAO, USA

19. Kovalev Yu., NRAO, USA

20. Lobanov A., MPIfR, Germany

21. Langston G., NRAO, USA

22. Popov M.V., ASC, Russia

23. Preston R., JPL NASA, USA

24. Rausch D., NASA, USA

25. Romney J., NRAO, USA

26. Savinell C., NASA, USA

27. Slysh V.I., ASC, Russia

28. Urpo S., HUT, Finland

29. Vasilkov V.I., ASC, Russia

30. Zensus A., MPIfR, Germany

 

 

 

Appendix B

The list of used acronyms

 

 

ASC Astro Space Center of Lebedev Physical Instutute

SRT Space Radio Telescope (all scientific payload including 10-m dish)

TMS Spacecraft Telemetry System (technical)

VIRK Scientific high rate (up to 2x72 Mbit/s) radio complex, including transponder

EM Engineering Model

Focal Container hermetic package with the scientific payload; it contains receivers, microwave synthesizer, control unit and is placed in focal site of dish

Cold Plate cooled LNAs and antenna feed

FM Focal Module = Focal Container+Cold Plate

DC hermetic device container (part of payload); it contains Formatter, Rb oscillators, synthesizer, control unit and is placed under dish

DM Device Module = DC + H-maser

Electronic Complex all SRT electronics

TVT - Termo-Vacuum Tests

LA - Lavochkin Association

Service Module, Spacecraft bus spacecraft itself (without payload); sometimes in text Spacecraft =service module + payload