COVER INFORMATION Station: VLBA_HN (Code Hn ) Experiment: bw082 M87 movie pilot. Walker, Ly, Junor, Hardee Exp. Code: bw082a Schedule Version: 1.00 Processed by SCHED version: 6.04 March 2006 PI: R.C. Walker Address: NRAO, P.O. Box O Socorro, NM 87801 USA Phone: +1-505-835-7247 (w) / +1-505-835-3972 (h) EMAIL: cwalker@nrao.edu Fax: +1-505-835-7027 Phone during observation: +1-505-835-7247 (w) / +1-505-835-3972 (h) Observing mode: VLBA Notes: COVER LETTER: This 6 session project samples different possible frame rates for a 7mm movie of M87. It is needed prior to full movie observations because the rate of changes near the core is not known. It is likely that they have been severly undersampled by previous observations. Each session will use the same schedule. The sessions should fall in the following windows (days) after the first: 0, 3, 6, 12-16, 31-39, 80-100. The program committee has asked me to coordinate with Phillip Hicks on the scheduling. I will do so. I propose to use long range forcasts to identify a 6 day window in which to start, and then, at 12, 31, and 80 days, identify a day within the 5, 9, and 21 day windows that follow in which to do a session. Here is the key information from the time allocation email: ------------------ PROPOSAL STATUS ( 01/06/05 ): Approved for dynamic scheduling, high priority Proposal Selection Committee - December 3, 2004: We ask Phillip Hicks to seek permission from Craig Walker before starting the observing sequence, rather than having Phillip be responsible for making the long-term weather forecast. CURRENT TIME ALLOCATION: 6 times 10.0 hrs dynamically scheduled centered at LST 12.5 with 128 Mbits/sec recording --------------------- I apologize for the long delay in starting this project, but it will take my attention once started and, for personal reasons, I did not feel I was in a position to provide that over the last year. ------------------------------------------------------------------------- Schedule for VLBA_HN (Code Hn ) Page 2 bw082 M87 movie pilot. Walker, Ly, Junor, Hardee UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. For disks, the footages are really the GBytes TPStart: Tape motion start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) SYNC ---------------------------------------------------------------------------------------- --- Sat 8 Apr 2006 Day 98 --- Next scan frequencies: 43127.49 43127.49 43135.49 43135.49 Next BBC frequencies: 727.49 727.49 735.49 735.49 Next scan bandwidths: 8.00 8.00 8.00 8.00 01 37 45 OJ287 09 54 32 64.0 213.2 1.0 25.3 0 1 1 0 01 37 15 01 45 44 --- 10 02 32 63.1 217.0 1.1 28.0 479 F 1 8 01 37 38 01 47 48 3C274 10 04 36 46.0 122.9 -2.4 -39.0 55 1 1 8 01 47 18 02 02 45 --- 10 19 36 48.3 127.2 -2.2 -36.7 898 F 1 23 01 47 41 02 03 28 3C279 10 20 19 29.8 133.8 -2.6 -32.1 0 1 1 23 02 02 45 02 05 28 --- 10 22 19 30.0 134.3 -2.6 -31.8 120 F 1 26 02 02 45 02 06 11 3C274 10 23 03 48.8 128.2 -2.1 -36.1 0 1 1 26 02 05 28 02 21 09 --- 10 38 03 50.9 132.9 -1.9 -33.3 898 F 1 41 02 05 28 02 21 52 3C279 10 38 47 32.1 138.4 -2.3 -29.3 0 1 1 41 02 21 09 02 23 52 --- 10 40 47 32.4 138.9 -2.3 -28.9 120 F 1 44 02 21 09 02 24 36 3C274 10 41 31 51.3 134.0 -1.8 -32.6 0 1 1 44 02 23 52 02 39 34 --- 10 56 31 53.2 139.1 -1.6 -29.4 898 F 1 59 02 23 52 02 40 18 3C279 10 57 15 34.2 143.2 -2.0 -26.1 0 1 1 59 02 39 34 02 42 17 --- 10 59 15 34.5 143.8 -2.0 -25.8 120 F 1 61 02 39 34 02 43 02 3C274 10 59 59 53.6 140.4 -1.5 -28.6 0 1 1 61 02 42 17 02 57 59 --- 11 14 59 55.3 146.0 -1.3 -24.8 898 F 1 77 02 42 17 02 58 43 3C279 11 15 43 36.1 148.4 -1.7 -22.7 0 1 1 77 02 57 59 03 00 43 --- 11 17 43 36.3 148.9 -1.6 -22.3 120 F 1 79 02 57 59 03 01 27 3C274 11 18 28 55.6 147.4 -1.2 -23.8 0 1 1 79 03 00 43 03 16 25 --- 11 33 28 57.0 153.5 -1.0 -19.5 898 F 1 94 03 00 43 03 17 09 3C279 11 34 13 37.8 153.7 -1.4 -19.0 0 1 1 94 03 16 25 03 19 09 --- 11 36 13 37.9 154.3 -1.3 -18.6 120 F 1 97 03 16 25 03 19 54 3C274 11 36 57 57.2 155.0 -0.9 -18.5 0 1 1 97 03 19 09 03 34 51 --- 11 51 57 58.3 161.6 -0.7 -13.7 898 F 1 112 03 19 09 03 35 36 3C279 11 52 42 39.1 159.4 -1.1 -15.0 0 1 1 112 03 34 51 03 37 35 --- 11 54 42 39.3 160.0 -1.0 -14.6 120 F 1 115 03 34 51 Schedule for VLBA_HN (Code Hn ) Page 3 bw082 M87 movie pilot. Walker, Ly, Junor, Hardee UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. For disks, the footages are really the GBytes TPStart: Tape motion start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) SYNC ---------------------------------------------------------------------------------------- --- Sat 8 Apr 2006 Day 98 --- 03 38 20 3C274 11 55 26 58.5 163.1 -0.6 -12.5 0 1 1 115 03 37 35 03 53 17 --- 12 10 26 59.1 170.1 -0.3 -7.4 898 F 1 130 03 37 35 03 54 01 3C279 12 11 10 40.2 165.2 -0.8 -10.9 0 1 1 130 03 53 17 03 56 01 --- 12 13 10 40.3 165.8 -0.7 -10.4 120 F 1 133 03 53 17 03 58 01 OJ287 12 15 10 42.5 257.5 3.3 49.6 53 1 1 133 03 57 31 04 03 00 --- 12 20 10 41.6 258.5 3.4 49.8 299 F 1 138 03 57 54 04 04 50 J1159+2914 12 22 01 75.6 199.7 0.4 16.5 36 1 1 138 04 04 20 04 09 49 =1156+295 12 27 01 75.2 203.9 0.5 19.8 299 F 1 143 04 04 43 04 10 51 3C274 12 28 03 59.4 178.5 -0.1 -1.1 24 1 1 143 04 10 21 04 25 48 --- 12 43 03 59.3 185.7 0.2 4.3 898 F 1 158 04 10 44 04 26 33 3C279 12 43 47 41.2 175.8 -0.2 -3.1 2 1 1 158 04 25 48 04 28 32 --- 12 45 47 41.2 176.4 -0.2 -2.6 120 F 1 161 04 25 48 04 29 17 3C274 12 46 32 59.2 187.4 0.3 5.5 2 1 1 161 04 28 32 04 44 14 --- 13 01 32 58.7 194.4 0.5 10.7 898 F 1 176 04 28 32 04 44 59 3C279 13 02 16 41.2 181.9 0.1 1.4 3 1 1 176 04 44 14 04 46 58 --- 13 04 16 41.2 182.6 0.1 1.9 120 F 1 179 04 44 14 04 47 43 3C274 13 05 01 58.6 196.0 0.6 11.9 4 1 1 179 04 46 58 05 02 40 --- 13 20 01 57.6 202.7 0.8 16.8 898 F 1 194 04 46 58 05 03 25 3C279 13 20 45 40.9 188.0 0.4 5.9 5 1 1 194 05 02 40 05 05 24 --- 13 22 45 40.9 188.6 0.4 6.3 120 F 1 197 05 02 40 05 06 08 3C274 13 23 30 57.4 204.2 0.9 17.9 5 1 1 197 05 05 24 05 21 06 --- 13 38 30 56.1 210.5 1.1 22.4 898 F 1 212 05 05 24 05 21 50 3C279 13 39 14 40.3 194.0 0.7 10.2 6 1 1 212 05 21 06 05 23 50 --- 13 41 14 40.2 194.6 0.7 10.7 120 F 1 214 05 21 06 05 24 34 3C274 13 41 58 55.8 211.9 1.2 23.3 7 1 1 214 05 23 50 05 39 31 --- 13 56 58 54.2 217.7 1.4 27.3 898 F 1 230 05 23 50 05 40 16 3C279 13 57 42 39.3 199.8 1.0 14.5 8 1 1 230 05 39 31 05 42 15 --- 13 59 42 39.2 200.4 1.1 14.9 120 F 1 232 05 39 31 Schedule for VLBA_HN (Code Hn ) Page 4 bw082 M87 movie pilot. Walker, Ly, Junor, Hardee UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. For disks, the footages are really the GBytes TPStart: Tape motion start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) SYNC ---------------------------------------------------------------------------------------- --- Sat 8 Apr 2006 Day 98 --- 05 43 00 3C274 14 00 27 53.8 219.0 1.5 28.1 9 1 1 232 05 42 15 05 57 57 --- 14 15 27 52.0 224.2 1.7 31.5 898 F 1 248 05 42 15 05 58 42 3C279 14 16 11 38.0 205.5 1.3 18.5 10 1 1 248 05 57 57 06 00 41 --- 14 18 11 37.8 206.1 1.4 18.9 120 F 1 250 05 57 57 06 01 26 3C274 14 18 56 51.6 225.4 1.8 32.3 11 1 1 250 06 00 41 06 16 24 --- 14 33 56 49.5 230.2 2.0 35.2 898 F 1 265 06 00 41 06 17 08 3C279 14 34 41 36.4 210.9 1.6 22.2 12 1 1 265 06 16 24 06 19 08 --- 14 36 41 36.2 211.5 1.7 22.6 120 F 1 268 06 16 24 06 21 07 J1159+2914 14 38 41 55.5 259.8 2.6 55.6 75 1 1 268 06 20 37 06 26 07 =1156+295 14 43 41 54.6 260.9 2.7 55.9 299 F 1 273 06 21 00 06 28 08 J1310+3220 14 45 42 68.5 248.2 1.6 53.6 87 1 1 273 06 27 38 06 33 07 =1308+326 14 50 42 67.7 249.9 1.7 54.4 299 F 1 279 06 28 01 06 35 54 3C274 14 53 29 46.7 235.9 2.4 38.4 119 1 1 279 06 35 24 06 50 51 --- 15 08 29 44.3 240.0 2.6 40.5 898 F 1 294 06 35 47 06 51 35 3C279 15 09 14 32.7 220.3 2.2 28.4 15 1 1 294 06 50 51 06 53 35 --- 15 11 14 32.5 220.8 2.2 28.8 120 F 1 296 06 50 51 06 54 19 3C274 15 11 58 43.8 240.9 2.7 40.9 16 1 1 296 06 53 35 07 09 17 --- 15 26 58 41.3 244.6 2.9 42.6 898 F 1 311 06 53 35 07 10 01 3C279 15 27 42 30.4 225.0 2.5 31.4 16 1 1 311 07 09 17 07 12 00 --- 15 29 42 30.2 225.5 2.6 31.7 120 F 1 314 07 09 17 07 12 44 3C274 15 30 26 40.8 245.4 3.0 43.0 16 1 1 314 07 12 00 07 27 41 --- 15 45 26 38.2 248.8 3.2 44.3 898 F 1 329 07 12 00 07 28 24 3C279 15 46 08 27.9 229.4 2.8 34.0 16 1 1 329 07 27 41 07 30 24 --- 15 48 08 27.7 229.9 2.9 34.2 120 F 1 332 07 27 41 07 31 06 3C274 15 48 51 37.7 249.6 3.3 44.6 17 1 1 332 07 30 24 07 46 04 --- 16 03 51 35.1 252.8 3.5 45.7 898 F 1 347 07 30 24 07 46 46 3C279 16 04 33 25.3 233.6 3.1 36.3 16 1 1 347 07 46 04 07 48 45 --- 16 06 33 25.0 234.0 3.2 36.6 120 F 1 350 07 46 04 Schedule for VLBA_HN (Code Hn ) Page 5 bw082 M87 movie pilot. Walker, Ly, Junor, Hardee UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. For disks, the footages are really the GBytes TPStart: Tape motion start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) SYNC ---------------------------------------------------------------------------------------- --- Sat 8 Apr 2006 Day 98 --- 07 49 27 3C274 16 07 15 34.5 253.5 3.6 45.9 17 1 1 350 07 48 45 08 04 25 --- 16 22 15 31.8 256.5 3.9 46.8 898 F 1 365 07 48 45 08 05 05 3C279 16 22 56 22.5 237.6 3.4 38.4 16 1 1 365 08 04 25 08 07 05 --- 16 24 56 22.2 238.0 3.5 38.6 120 F 1 367 08 04 25 08 07 45 3C274 16 25 36 31.2 257.2 3.9 47.0 16 1 1 367 08 07 05 08 22 43 --- 16 40 36 28.5 260.0 4.2 47.6 898 F 1 382 08 07 05 08 23 22 3C279 16 41 15 19.6 241.4 3.7 40.2 16 1 1 382 08 22 43 08 25 22 --- 16 43 15 19.3 241.8 3.8 40.4 120 F 1 385 08 22 43 08 26 01 3C274 16 43 55 27.9 260.7 4.2 47.7 16 1 1 385 08 25 22 08 40 58 --- 16 58 55 25.2 263.4 4.5 48.1 898 F 1 400 08 25 22 08 41 37 3C279 16 59 34 16.7 245.0 4.1 41.8 16 1 1 400 08 40 58 08 43 37 --- 17 01 34 16.3 245.4 4.1 42.0 120 F 1 403 08 40 58 08 45 37 J1159+2914 17 03 34 29.2 284.1 5.1 54.4 88 1 1 403 08 45 07 08 50 36 =1156+295 17 08 34 28.3 284.8 5.1 54.2 299 F 1 408 08 45 30 08 51 13 J1310+3220 17 09 11 42.6 277.8 4.0 59.1 2 1 1 408 08 50 36 08 56 12 =1308+326 17 14 11 41.7 278.5 4.1 58.9 299 F 1 413 08 50 36 08 57 02 3C274 17 15 01 22.3 266.3 4.7 48.4 5 1 1 413 08 56 32 09 11 59 --- 17 30 01 19.5 268.9 5.0 48.5 898 F 1 428 08 56 55 09 12 42 3C279 17 30 43 11.4 250.8 4.6 44.0 20 1 1 428 09 11 59 09 14 42 --- 17 32 43 11.0 251.2 4.6 44.2 120 F 1 431 09 11 59 09 15 25 3C274 17 33 27 18.9 269.4 5.0 48.5 22 1 1 431 09 14 42 09 30 23 --- 17 48 27 16.2 272.0 5.3 48.5 898 F 1 446 09 14 42 09 31 07 3C279 17 49 11 8.2 254.1 4.9 45.1 22 1 1 446 09 30 23 09 33 06 --- 17 51 11 7.8 254.5 4.9 45.2 120 F 1 449 09 30 23 09 33 51 3C274 17 51 56 15.5 272.6 5.3 48.5 23 1 1 449 09 33 06 09 48 49 --- 18 06 56 12.8 275.1 5.6 48.3 898 F 1 464 09 33 06 09 49 32 3C279 18 07 40 4.9 257.4 5.2 H 45.9 22 1 1 464 09 48 49 09 51 32 --- 18 09 40 4.5 257.7 5.2 H 46.0 0 F 1 467 09 48 49 Schedule for VLBA_HN (Code Hn ) Page 6 bw082 M87 movie pilot. Walker, Ly, Junor, Hardee UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. For disks, the footages are really the GBytes TPStart: Tape motion start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) SYNC ---------------------------------------------------------------------------------------- --- Sat 8 Apr 2006 Day 98 --- 09 52 15 3C274 18 10 23 12.2 275.7 5.7 48.2 22 1 1 467 09 51 32 10 07 12 --- 18 25 23 9.4 278.2 5.9 47.9 898 F 1 482 09 51 32 10 10 30 3C274 18 28 41 8.8 278.7 6.0 47.8 191 1 1 482 10 10 00 10 25 28 --- 18 43 41 6.1 281.2 6.2 47.3 898 F 1 497 10 10 23 10 28 40 3C274 18 46 54 5.5 281.7 6.3 47.2 185 1 1 497 10 28 10 10 43 37 --- 19 01 54 2.9 284.2 6.5 H 46.6 0 F 1 512 10 28 33 10 46 50 3C274 19 05 07 2.3 284.8 6.6 H 46.4 186 1 1 512 10 46 20 11 01 48 --- 19 20 07 -0.3 287.3 6.8 D 45.7 0 F 1 527 10 46 43 11 25 06 1726+455 19 43 29 65.7 287.9 2.3 83.8 1266 1 1 527 11 24 36 11 28 06 --- 19 46 29 65.2 288.0 2.3 83.4 180 F 1 530 11 24 59 11 31 23 1751+288 19 49 48 62.8 248.2 1.9 50.9 165 1 1 530 11 30 53 11 34 23 --- 19 52 48 62.3 249.1 2.0 51.3 180 F 1 533 11 31 16 SETUP FILE INFORMATION: NOTE: If DOPPLER, FREQ, or BW were used, see the individual scans for the final BBC settings. Setup file: bw082.set Matches group v7mm_c8 in /home/arana/cwalker/sched/catalogs/freq.dat Setup group: 2 Station: VLBA_HN Total bit rate: 128 Format: VLBA1:4 Bits per sample: 2 Sample rate: 16.000 Number of channels: 4 Speedup factor: 2.00 Disk used to record data. 1st LO= 42400.00 42400.00 42400.00 42400.00 Net SB= U U U U Pol. = RCP LCP RCP LCP BBC = 1 2 3 4 BBC SB= U U U U IF = A C A C VLBA FE= 7mm omit 7mm omit VLBA Synth= 15.4 7.6 11.6 The following frequency sets based on this setup were used. Frequency Set: 2 Setup file default. Used pcal sets: 1 LO sum= 43127.49 43127.49 43135.49 43135.49 BBC fr= 727.49 727.49 735.49 735.49 Bandwd= 8.000 8.000 8.000 8.000 The following pulse cal sets were used with this setup: Pulse cal detection set: 1 PCAL = 1MHZ PCALXB1= S1 S3 S1 S3 S1 S2 S3 S4 PCALXB2= S2 S4 S2 S4 M1 M2 M3 M4 PCALFR1= 510 510 6510 6510 0 0 0 0 PCALFR2= 510 510 6510 6510 0 0 0 0 Track assignments are: track1= 2, 18, 3, 19 barrel=roll_off SOURCE LIST -- bw082 M87 movie pilot. Walker, Ly, Junor, Hardee Catalog positions marked with *. Precession of date coordinates is based on stop time of first scan. Names used in schedule marked with *. Short names used in VLA and SNAP files marked with +. Observation date used in B1950/J2000 coordinate conversion (PRECDATE): 1979.900 No adjustments are made for rates (DRA, DDEC). Scan hours are for recording scans only. Baseline hours are only counted for scans above horizon at both ends. Source Source position (RA/Dec) Error (B1950) (J2000) (Date) (mas) J0854+2006 08 51 57.250618 * 08 54 48.874930 08 55 10.989287 0.21 0851+202 20 17 58.41741 * 20 06 30.64086 20 05 09.67465 0.40 J0854+2006 /home/arana/cwalker/sched/catalogs/sources.vlba J0854+20 VLBA Calib Survey - GSFC sols. - created L.Petrov 2005f_astro * OJ287 0.216 scan hours, 9.723 baseline hours above horizon. * J1159+2914 11 56 57.786209 * 11 59 31.833910 11 59 52.744463 0.23 1156+295 29 31 25.73874 * 29 14 43.82684 29 12 34.98941 0.40 J1159+29 /home/arana/cwalker/sched/catalogs/sources.vlba J1159+2914 VLBA Calib Survey - GSFC sols. - created L.Petrov 2005f_astro J1159+2914 0.249 scan hours, 11.219 baseline hours above horizon. J1230+1223 12 28 17.569279 * 12 30 49.423381 12 31 09.762255 0.31 1228+126 12 40 01.74901 * 12 23 28.04383 12 21 16.04731 0.20 * 3C274 /home/arana/cwalker/sched/catalogs/sources.vlba J1230+12 VLBA Calib Survey - GSFC sols. - created L.Petrov 2005f_astro J1230+1223 7.230 scan hours, 292.449 baseline hours above horizon. J1256-0547 12 53 35.831291 * 12 56 11.166559 12 56 31.752519 0.20 1253-055 -05 31 07.99586 *-05 47 21.52472 -05 49 32.98891 0.30 * 3C279 /home/arana/cwalker/sched/catalogs/sources.vlba J1256-05 VLBA Calib Survey - GSFC sols. - created L.Petrov 2005f_astro J1256-0547 0.964 scan hours, 36.334 baseline hours above horizon. * J1310+3220 13 08 07.560131 * 13 10 28.663850 13 10 48.118906 0.24 1308+326 32 36 40.23883 * 32 20 43.78290 32 18 35.34772 0.40 J1310+32 /home/arana/cwalker/sched/catalogs/sources.vlba J1310+3220 VLBA Calib Survey - GSFC sols. - created L.Petrov 2005f_astro J1310+3220 0.166 scan hours, 7.480 baseline hours above horizon. J1727+4530 17 26 01.198750 * 17 27 27.650804 17 27 39.330524 0.29 * 1726+455 45 33 04.55118 * 45 30 39.73133 45 29 55.12204 0.40 J1727+45 /home/arana/cwalker/sched/catalogs/sources.vlba J1727+4530 VLBA Calib Survey - GSFC sols. - created L.Petrov 2005f_astro 0.050 scan hours, 2.244 baseline hours above horizon. J1753+2848 17 51 45.401869 * 17 53 42.473641 17 53 57.576149 0.23 * 1751+288 28 48 36.64959 * 28 48 04.93887 28 47 36.64878 0.40 J1753+28 /home/arana/cwalker/sched/catalogs/sources.vlba J1753+2848 VLBA Calib Survey - GSFC sols. - created L.Petrov 2005f_astro 0.050 scan hours, 2.244 baseline hours above horizon. The solar corona can cause unstable phases for sources too close to the Sun. SCHED provides warnings at individual scans for distances less than 10 degrees. The distance from the Sun to each source in this schedule is: Source Sun distance (deg) OJ287 112.3 J1159+2914 140.1 3C274 158.5 3C279 177.0 J1310+3220 140.5 1726+455 101.8 1751+288 102.4 Barry Clark estimates from predictions by Ketan Desai of IPM scattering sizes that the Sun will cause amplitude reductions on the longest VLBA baselines at a solar distance of 60deg F^(-0.6) where F is in GHz. For common VLBI bands, this is: 327 MHz 117. deg 610 MHz 81. deg 1.6 GHz 45. deg 2.3 GHz 36. deg 5.0 GHz 23. deg 8.4 GHz 17. deg 15.0 GHz 12. deg 22.0 GHz 9. deg 43.0 GHz 6. deg