Voyager Mission Operations Status Report # 2010-05-07,  Week Ending May 7, 2010

 

Command Transmission & Verification Operations

 

Voyager 1 command operations consisted of the uplink of two SID MRO’S, A Command Loss Timer Reset and two SID MRO’s on 05/05 [DOY 125/0254z].  The spacecraft received all commands sent and all commands were verified.

 

Voyager 2 command operations consisted of the uplink of bracketed TWNC ON and EL-40 commands on 05/03 [DOY 123/2040z] and bracketed EL-40 commands on 05/05 [DOY 125/1702z]. The spacecraft received the commands sent.

 

Sequence Generation Operations

 

No overlay sequence development activity during this report period.

 

Data Return Operations

 

Voyager 1 Data Processing and Operations:

 

There were 115.8 hours of DSN scheduled support for Voyager 1 of which 20.6 hours were large aperture coverage. There were no real-time or schedule support changes made during the period.

 

There was one significant outage of 1.8 hours on 05/04 [DOY 124] due to rain at DSS-45 [DR C105361].

 

Science instrument performance was nominal for all activities during this period.  One frame of GS-4 data was recorded this week.  A second frame of GS-4 data was recorded on May 7.  The EDR backlog is 2 day.

 

Voyager 2 Data Processing and Operations:

 

There were 58.1 hours of DSN scheduled support for Voyager 2of which 39.8 hours were large aperture coverage. There were no real-time or schedule support changes made during the period.

 

There were eight outages during the period the ground systems were not able to process CR-5T Science telemetry due to an ongoing spacecraft Flight Data Subsystem (FDS) anomaly, ISA 25395. 

 

On 05/01 [DOY 121/2315:16] the spacecraft was commanded to the engineering only format EL-40.  The ground locked-up and the health and state of the spacecraft were determined.  On board mode changes on 05/04 [DOY 124/1814:03] took the spacecraft back to the CR-5T format still manifesting the Flight Data System (FDS) anomaly. 

 

The spacecraft was again commanded back to the EL-40 mode on 05/06 [DOY 126/1840:15] and remained in the engineering mode for the remainder of the period.

 

The data outages associated with the CR-5T telemetry downlink periods; the dates, outage durations, stations supporting and associated DRs for the period are:

  1. 05/01 [DOY 121] 0.7 hours DSS-43 [DR C107351]
  2. 05/01 [DOY 121] 2.3 hours DSS-45 [DR C107352]
  3. 05/01 [DOY 121] 6.7 hours DSS-45 [DR C107353]
  4. 05/01 [DOY 121] 2.4 hours DSS-43 [DR C107354]

Processing EL-40 05/01 [DOY 121/2315:46]  -  05/04 [DOY 124/1914:03]

  1. 05/04 [DOY 124] 3.2 hours DSS-45 [No DR written]
  2. 05/05 [DOY 125] 3.1 hours DSS-43 [No DR written]
  3. 05/05 [DOY 125] 2.6 hours DSS-34 [DR C107368]
  4. 05/06 [DOY 126] 1.0 hours DSS-43 [DR C107369]

Processing EL-40 05/06 [DOY 126/1840:15 – end of period]

 

No science data was received since day 112 due to the Flight Data System (FDS) anomaly on the spacecraft.  The EDR backlog is 0 days.

 

 

Flight System Performance

 

Voyager 1 performance was nominal during this report period. Activities included an ASCAL on 5/4 [DOY 124] and a MAGROL on 5/6 [DOY 127].

 

Voyager 2 performance was nominal during this report period. On 5/1 [DOY 122], the results of commands to EL-40 were received and the DSN was able to lock-up on the data.  The problem seemed to be with the CR-5T data mode.  It was determined that all of the spacecraft had be delayed by ~2h35m.  Therefore, the PMPCAL on 5/4 ended in CR-5T data mode.  The spacecraft was switched back to the EL-40 data mode on 5/6 [DOY 126].

 

PROPELLANT/POWER CONSUMABLES STATUS AS OF THIS REPORT

 

 

Spacecraft

Consumption

One Week (Gm)

Propellant

Remaining (Kg)

Output

(Watts)

Margin

(Watts)

1

6.94

26.19

273.8

28

2

*

27.88

275.1

14**

*No CR-5T data                 **Based on EL-40 data

 

RANGE, VELOCITY AND ROUND TRIP LIGHT TIME AS OF THIS REPORT

 

 

Voyager 1

Voyager 2

Distance from the Sun (Km)

16,966,000,000

13,782,000,000

Distance from the Sun (Mi)

10,542,000,000

8,563,000,000

Distance from the Earth (Km)

16,857,000,000

13,725,000,000

Distance from the Earth (Mi)

10,475,000,000

8,528,000,000

Total Distance Traveled Since Launch (Km)

21,902,000,000

20,928,000,000

Total Distance Traveled Since Launch (Mi)

13,609,000,000

13,004,000,000

Velocity Relative to Sun  (Km/sec)

17.070

15.485

Velocity Relative to Sun  (Mi/hr)

38,182

34,638

Velocity Relative to Earth  (Km/sec)

26.082

23.171

Velocity Relative to Earth  (Mi/hr)

58,344

51,832

Round Trip Light Time (hh:mm:ss)

31:13:24

25:25:52