COVER INFORMATION Station: TORUN (Code Tr ) Experiment: Fine-scale imaging of M87 Exp. Code: gs042 Schedule Version: 1.00 Processed by SCHED version: 11.40 Release 11.4. March 14, 2015 PI: Tuomas Savolainen Address: Aalto University Metsahovi Radio Observatory Metsahovintie 114, 02540 Kylmala, Finland Phone: +358505819717 EMAIL: tuomas.k.savolainen@aalto.fi Fax: Phone during observation: +358505819717 Observing mode: K-band dual-pol Notes: K-band, Radioastron-compatible frequency setup P-CAL is ON Tsys is ON auto-level (AGC) is ON Schedule for TORUN (Code Tr ) Page 2 Fine-scale imaging of M87 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Mon 14 May 2018 Day 134 --- Next scan frequencies: 22236.00 22236.00 22236.00 22236.00 Next BBC frequencies: 736.00 736.00 736.00 736.00 Next scan bandwidths: 16.00 16.00 16.00 16.00 13 10 30 1228+126 05 53 41 4.2 75.1 -6.6 -36.4 0 0 13 10 30 13 20 00 --- 06 03 12 5.6 76.9 -6.5 -36.8 570 18 13 10 31 13 20 30 1228+126 06 03 43 5.7 77.0 -6.5 -36.8 24 18 13 20 30 13 29 50 --- 06 13 04 7.0 78.9 -6.3 -37.1 560 36 13 20 31 13 37 20 1236+077 06 20 35 3.0 81.6 -6.3 D -36.8 421 36 13 37 20 13 38 50 --- 06 22 06 3.2 81.9 -6.3 -36.8 0 39 13 37 21 13 39 30 1228+126 06 22 46 8.5 80.8 -6.1 -37.3 6 39 13 39 30 13 48 50 --- 06 32 07 9.9 82.6 -6.0 -37.6 560 57 13 39 31 13 49 20 1228+126 06 32 37 9.9 82.7 -6.0 -37.6 24 57 13 49 20 13 53 40 --- 06 36 58 10.6 83.6 -5.9 -37.6 260 65 13 49 21 13 54 10 1156+295 06 37 28 28.3 78.2 -5.4 -42.3 -51 65 13 54 10 13 55 50 --- 06 39 08 28.5 78.5 -5.4 -42.4 49 69 13 54 11 13 56 20 1156+295 06 39 38 28.6 78.6 -5.3 -42.4 24 69 13 56 20 14 00 40 --- 06 43 59 29.2 79.4 -5.3 -42.5 260 77 13 56 21 14 01 10 1236+077 06 44 29 6.5 86.4 -5.9 -37.2 -68 77 14 01 10 14 03 10 --- 06 46 30 6.8 86.8 -5.9 -37.2 52 81 14 01 11 14 04 00 1228+126 06 47 20 12.1 85.6 -5.7 -37.8 16 81 14 04 00 14 13 10 --- 06 56 31 13.5 87.4 -5.6 -37.9 550 98 14 04 01 14 14 10 1226+023 06 57 31 5.7 94.3 -5.5 -36.8 17 98 14 14 10 14 18 10 --- 07 01 32 6.3 95.1 -5.5 -36.8 240 106 14 14 11 14 18 40 1236+077 07 02 02 9.2 89.9 -5.6 -37.3 4 106 14 18 40 14 20 10 --- 07 03 32 9.4 90.2 -5.6 -37.3 90 109 14 18 41 14 21 00 1228+126 07 04 22 14.7 89.0 -5.5 -37.9 16 109 14 21 00 14 27 20 --- 07 10 44 15.6 90.3 -5.4 -37.9 380 121 14 21 01 14 27 50 1236+077 07 11 14 10.5 91.7 -5.5 -37.2 -3 121 14 27 50 14 29 10 --- 07 12 34 10.7 92.0 -5.5 -37.2 77 124 14 27 51 Schedule for TORUN (Code Tr ) Page 3 Fine-scale imaging of M87 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Mon 14 May 2018 Day 134 --- ---------- K-band VLBI scans. Space segment 02: 1228+126 ---------- 14 30 00 1228+126 07 13 24 16.0 90.8 -5.3 -37.9 16 124 14 30 00 14 50 00 --- 07 33 27 19.0 94.9 -5.0 -37.8 1200 162 14 30 01 14 50 30 1228+126 07 33 57 19.1 95.0 -5.0 -37.8 24 162 14 50 30 14 51 30 --- 07 34 58 19.3 95.2 -4.9 -37.7 60 164 14 50 31 14 52 10 1228+126 07 35 38 19.4 95.3 -4.9 -37.7 34 164 14 52 10 15 10 00 --- 07 53 31 22.0 99.0 -4.6 -37.4 1070 198 14 52 11 ---------- K-band VLBI scans. Ground segment 03: ---------- 15 10 20 1236+077 07 53 51 16.9 100.4 -4.8 -36.6 -13 198 15 10 20 15 11 50 --- 07 55 21 17.1 100.7 -4.7 -36.5 77 201 15 10 21 15 12 40 1228+126 07 56 11 22.4 99.6 -4.6 -37.3 16 201 15 12 40 15 22 10 --- 08 05 43 23.8 101.6 -4.4 -37.0 570 220 15 12 41 15 23 10 1226+023 08 06 43 15.8 108.6 -4.4 -34.7 16 220 15 23 10 15 28 10 --- 08 11 44 16.5 109.7 -4.3 -34.5 300 229 15 23 11 15 28 40 1236+077 08 12 14 19.6 104.3 -4.5 -35.9 4 229 15 28 40 15 30 10 --- 08 13 44 19.8 104.6 -4.4 -35.9 90 232 15 28 41 15 31 00 1228+126 08 14 34 25.1 103.5 -4.3 -36.7 16 232 15 31 00 15 40 30 --- 08 24 06 26.5 105.6 -4.1 -36.3 570 250 15 31 01 15 42 10 1253-055 08 25 46 8.2 111.4 -4.5 -34.2 17 250 15 42 10 15 46 10 --- 08 29 46 8.8 112.3 -4.5 -34.0 240 258 15 42 11 15 47 50 1228+126 08 31 27 27.6 107.2 -4.0 -36.0 16 258 15 47 50 15 56 50 --- 08 40 28 28.9 109.2 -3.9 -35.5 540 275 15 47 51 15 57 30 1228+126 08 41 08 29.0 109.4 -3.8 -35.4 34 275 15 57 30 16 06 50 --- 08 50 30 30.3 111.5 -3.7 -34.9 560 293 15 57 31 16 08 30 1156+295 08 52 10 48.3 106.0 -3.1 -41.4 19 293 16 08 30 16 12 30 --- 08 56 11 48.9 107.0 -3.1 -41.1 240 301 16 08 31 16 14 00 1228+126 08 57 41 31.3 113.2 -3.6 -34.4 10 301 16 14 00 16 22 30 --- 09 06 12 32.4 115.2 -3.4 -33.8 510 317 16 14 01 16 23 10 1228+126 09 06 53 32.5 115.4 -3.4 -33.7 34 317 16 23 10 16 32 30 --- 09 16 14 33.8 117.7 -3.3 -33.0 560 335 16 23 11 Schedule for TORUN (Code Tr ) Page 4 Fine-scale imaging of M87 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Mon 14 May 2018 Day 134 --- 16 33 30 1226+023 09 17 14 25.3 124.5 -3.2 -29.7 14 335 16 33 30 16 37 30 --- 09 21 15 25.8 125.5 -3.1 -29.3 240 343 16 33 31 16 38 30 1228+126 09 22 15 34.6 119.2 -3.2 -32.5 13 343 16 38 30 16 47 30 --- 09 31 17 35.7 121.5 -3.0 -31.6 540 360 16 38 31 16 48 10 1228+126 09 31 57 35.8 121.6 -3.0 -31.6 34 360 16 48 10 16 57 30 --- 09 41 18 37.0 124.1 -2.8 -30.6 560 378 16 48 11 16 59 10 1253-055 09 42 58 18.3 128.3 -3.2 -28.3 16 378 16 59 10 17 03 10 --- 09 46 59 18.7 129.2 -3.2 -27.9 240 386 16 59 11 17 04 50 1228+126 09 48 39 37.9 126.0 -2.7 -29.8 14 386 17 04 50 17 14 10 --- 09 58 01 39.0 128.6 -2.6 -28.7 560 404 17 04 51 17 14 50 1228+126 09 58 41 39.1 128.7 -2.6 -28.6 34 404 17 14 50 17 25 00 --- 10 08 53 40.3 131.6 -2.4 -27.4 610 423 17 14 51 17 25 50 1228+126 10 09 43 40.4 131.8 -2.4 -27.2 44 423 17 25 50 17 34 20 --- 10 18 14 41.3 134.3 -2.2 -26.1 510 440 17 25 51 17 36 00 1156+295 10 19 55 59.8 132.5 -1.7 -30.5 17 440 17 36 00 17 39 20 --- 10 23 15 60.2 133.7 -1.6 -29.8 200 446 17 36 01 17 41 00 1228+126 10 24 55 42.0 136.3 -2.1 -25.1 18 446 17 41 00 17 49 20 --- 10 33 17 42.9 138.8 -2.0 -23.9 500 462 17 41 01 17 50 20 1226+023 10 34 17 33.5 144.5 -1.9 -20.4 11 462 17 50 20 17 54 20 --- 10 38 18 33.9 145.7 -1.9 -19.8 240 470 17 50 21 17 55 20 1253-055 10 39 18 24.2 141.9 -2.3 -21.9 10 470 17 55 20 17 59 20 --- 10 43 18 24.6 142.9 -2.2 -21.4 240 478 17 55 21 18 01 00 1228+126 10 44 59 44.0 142.4 -1.8 -22.0 14 478 18 01 00 18 04 20 --- 10 48 19 44.3 143.5 -1.7 -21.5 200 484 18 01 01 ---------- K-band VLBI scans. Space segment 03: 1228+126 ---------- 18 05 00 1228+126 10 48 59 44.3 143.7 -1.7 -21.3 34 484 18 05 00 18 25 00 --- 11 09 03 46.0 150.2 -1.4 -17.8 1200 522 18 05 01 18 25 40 1228+126 11 09 43 46.0 150.5 -1.4 -17.6 34 522 18 25 40 18 45 00 --- 11 29 06 47.3 157.1 -1.0 -13.8 1160 560 18 25 41 Schedule for TORUN (Code Tr ) Page 5 Fine-scale imaging of M87 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Mon 14 May 2018 Day 134 --- ---------- K-band VLBI scans. Ground segment 04: ---------- 18 45 40 1228+126 11 29 46 47.4 157.3 -1.0 -13.7 34 560 18 45 40 18 55 00 --- 11 39 08 47.9 160.6 -0.9 -11.8 560 578 18 45 41 18 56 40 1156+295 11 40 48 65.8 169.5 -0.3 -7.2 19 578 18 56 40 19 00 10 --- 11 44 18 65.9 171.3 -0.3 -5.9 210 584 18 56 41 19 01 40 1228+126 11 45 49 48.2 163.0 -0.8 -10.3 10 584 19 01 40 19 09 40 --- 11 53 50 48.5 165.9 -0.6 -8.6 480 600 19 01 41 19 11 10 1253-055 11 55 20 29.6 162.3 -1.0 -10.6 5 600 19 11 10 19 14 40 --- 11 58 51 29.7 163.2 -1.0 -10.0 210 606 19 11 11 19 16 20 1228+126 12 00 31 48.7 168.4 -0.5 -7.1 15 606 19 16 20 19 24 40 --- 12 08 52 48.9 171.5 -0.4 -5.2 500 622 19 16 21 ---------- K-band VLBI scans. Ground segment 04: ---------- 19 25 40 1228+126 12 09 53 49.0 171.8 -0.4 -5.0 53 622 19 25 40 19 34 40 --- 12 18 54 49.1 175.2 -0.2 -2.9 540 640 19 25 41 19 35 50 1226+023 12 20 04 38.8 176.8 -0.2 -1.9 17 640 19 35 50 19 39 40 --- 12 23 55 38.8 178.0 -0.1 -1.2 230 647 19 35 51 19 40 50 1228+126 12 25 05 49.2 177.5 -0.1 -1.5 17 647 19 40 50 19 49 40 --- 12 33 56 49.2 180.8 0.0 0.5 530 664 19 40 51 19 51 10 1156+295 12 35 27 65.2 198.5 0.6 12.6 16 664 19 51 10 19 54 50 --- 12 39 07 65.0 200.3 0.6 13.8 220 671 19 51 11 19 56 20 1228+126 12 40 38 49.2 183.3 0.1 2.0 17 671 19 56 20 20 05 00 --- 12 49 19 49.0 186.6 0.3 4.0 520 688 19 56 21 20 06 40 1253-055 12 50 59 31.0 178.2 -0.1 -1.1 18 688 20 06 40 20 10 00 --- 12 54 20 31.0 179.2 -0.0 -0.5 200 694 20 06 41 20 11 40 1228+126 12 56 00 48.9 189.0 0.4 5.5 19 694 20 11 40 20 20 00 --- 13 04 21 48.7 192.1 0.5 7.4 500 710 20 11 41 20 20 40 1228+126 13 05 02 48.7 192.4 0.6 7.6 34 710 20 20 40 20 25 00 --- 13 09 22 48.5 193.9 0.6 8.5 260 719 20 20 41 Schedule for TORUN (Code Tr ) Page 6 Fine-scale imaging of M87 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Mon 14 May 2018 Day 134 --- ---------- K-band VLBI scans. Ground segment 04: ---------- 20 26 20 1228+126 13 10 43 48.5 194.4 0.6 8.8 73 719 20 26 20 20 35 30 --- 13 19 54 48.1 197.8 0.8 10.8 550 736 20 26 21 20 36 50 1156+295 13 21 14 61.8 219.7 1.3 26.1 14 736 20 36 50 20 40 30 --- 13 24 55 61.5 221.2 1.4 26.9 220 743 20 36 51 20 41 50 1228+126 13 26 15 47.8 200.0 0.9 12.1 15 743 20 41 50 20 50 30 --- 13 34 56 47.3 203.1 1.1 13.9 520 760 20 41 51 20 51 50 1226+023 13 36 17 37.0 200.9 1.1 12.4 28 760 20 51 50 20 55 30 --- 13 39 57 36.8 202.0 1.2 13.0 220 767 20 51 51 20 56 50 1228+126 13 41 18 46.9 205.3 1.2 15.2 28 767 20 56 50 21 05 30 --- 13 49 59 46.3 208.3 1.3 16.9 520 784 20 56 51 21 07 00 1253-055 13 51 29 29.9 195.6 0.9 9.4 15 784 21 07 00 21 10 30 --- 13 55 00 29.8 196.6 1.0 9.9 210 790 21 07 01 21 12 00 1228+126 13 56 30 45.8 210.5 1.4 18.1 16 790 21 12 00 21 20 30 --- 14 05 01 45.2 213.3 1.6 19.7 510 807 21 12 01 21 21 10 1228+126 14 05 42 45.1 213.5 1.6 19.8 34 807 21 21 10 21 30 00 --- 14 14 33 44.3 216.3 1.7 21.4 530 824 21 21 11 21 30 40 1228+126 14 15 13 44.3 216.5 1.7 21.5 34 824 21 30 40 21 39 00 --- 14 23 34 43.5 219.2 1.9 22.8 500 840 21 30 41 ---------- K-band VLBI scans. Space segment 04: 1228+126 ---------- 21 40 00 1228+126 14 24 35 43.4 219.5 1.9 23.0 54 840 21 40 00 21 56 40 --- 14 41 17 41.7 224.5 2.2 25.5 1000 872 21 40 01 21 57 20 1228+126 14 41 57 41.7 224.7 2.2 25.6 34 872 21 57 20 22 13 20 --- 14 58 00 39.9 229.4 2.4 27.8 960 903 21 57 21 22 14 00 1228+126 14 58 40 39.8 229.5 2.4 27.9 34 903 22 14 00 22 30 00 --- 15 14 43 37.9 234.0 2.7 29.8 960 933 22 14 01 22 31 20 1253-055 15 16 03 24.1 218.4 2.3 22.0 14 933 22 31 20 22 33 20 --- 15 18 03 23.9 218.9 2.3 22.3 120 937 22 31 21 22 35 00 1156+295 15 19 44 46.7 256.7 3.3 42.0 1 937 22 35 00 22 37 00 --- 15 21 44 46.4 257.1 3.4 42.1 120 941 22 35 01 Schedule for TORUN (Code Tr ) Page 7 Fine-scale imaging of M87 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Mon 14 May 2018 Day 134 --- 22 38 40 1228+126 15 23 24 36.9 236.3 2.9 30.7 43 941 22 38 40 22 42 40 --- 15 27 25 36.4 237.3 2.9 31.1 240 949 22 38 41 22 43 30 1228+126 15 28 15 36.3 237.5 2.9 31.2 44 949 22 43 30 22 52 00 --- 15 36 46 35.2 239.7 3.1 32.0 510 965 22 43 31 22 52 40 1228+126 15 37 27 35.1 239.9 3.1 32.1 34 965 22 52 40 22 56 40 --- 15 41 27 34.6 240.9 3.2 32.5 240 973 22 52 41 22 57 30 1228+126 15 42 17 34.4 241.1 3.2 32.5 44 973 22 57 30 23 10 00 --- 15 54 49 32.8 244.2 3.4 33.6 750 997 22 57 31 SETUP FILE INFORMATION: NOTE: If DOPPLER, FREQ, or BW were used, see the individual scans for the final BBC settings. ======== Setup file: ra1cm2.set --- WARNING --- This group does not match an entry in the frequency catalog. This might be ok because the catalog is not complete. But be very careful to be sure that the setup is correct. Setup group: 18 Station: TORUN Total bit rate: 256 Format: MARK5B Bits per sample: 2 Sample rate: 32.000 Number of channels: 4 DBE type: DBBC_DDC Speedup factor: 1.00 Disk used to record data. 1st LO= 21500.00 21500.00 21500.00 21500.00 Net SB= U U L L IF SB = U U U U Pol. = RCP LCP RCP LCP BBC = 1 5 1 5 BBC SB= U U L L IF = A1 B1 A1 B1 The following frequency sets based on these setups were used. Frequency Set: 13 Setup file default. Used with PCAL = 1MHz LO sum= 22236.00 22236.00 22236.00 22236.00 BBC fr= 736.00 736.00 736.00 736.00 Bandwd= 16.00 16.00 16.00 16.00 Matching frequency sets: 13 Track assignments are: track1= 2, 4, 6, 8 barrel=roll_off POSITIONS OF SOURCES USED IN RECORDING SCANS Source Source position (RA/Dec) Error (B1950) (J2000) (Date) (mas) * FAKERA 11 57 21.769299 * 12 00 00.000000 12 00 58.985352 0.00 85 16 41.77889 * 85 00 00.00000 84 54 13.48772 0.00 From catalog imbedded in main SCHED input file. fake circumpolar target for a TS to look at J1239+0730 12 36 52.308755 * 12 39 24.588327 12 40 20.487542 0.10 * 1236+077 07 46 45.39997 * 07 30 17.18902 07 24 18.52672 0.11 J1239+07 From catalog imbedded in main SCHED input file. rfc_2012b Petrov, 2012, unpublished 1855 observations * 1226+023 12 26 33.245835 * 12 29 06.699731 12 30 03.025117 0.00 J1229+0203 02 19 43.30547 * 02 03 08.59797 01 57 05.87367 0.00 3C273B ./gs042_sources.radioastron 3C273 AGN, rfc_2013d Petrov, 2013, unpublished 32011 observations, RA-AO4-07, RA-AO3-0 * 1253-055 12 53 35.831289 * 12 56 11.166557 12 57 08.371431 0.00 J1256-0547 -05 31 07.99603 *-05 47 21.52489 -05 53 17.34581 0.00 3C279 ./gs042_sources.radioastron AGN, rfc_2013d Petrov, 2013, unpublished 7924 observations, RA-AO4-07, RA-AO3-04 * 1228+126 12 28 17.569280 * 12 30 49.423382 12 31 45.092957 0.00 J1230+1223 12 40 01.74883 * 12 23 28.04365 12 17 28.41095 0.00 3C274 ./gs042_sources.radioastron M87 AGN, rfc_2013d Petrov, 2013, unpublished 55201 observations, RA-AO3-04, RA-AO3-0 VIR-A * 1156+295 11 56 57.786212 * 11 59 31.833913 12 00 28.033628 0.00 J1159+2914 29 31 25.73868 * 29 14 43.82678 29 08 45.29167 0.00 ./gs042_sources.radioastron AGN, MASIV, rfc_2013d Petrov, 2013, unpublished 70591 observations, RA-AO3-04, R SOURCE SCAN SUMMARY FOR SOURCES LISTED ABOVE Scan hours are for recording scans only. Baseline hours are only counted for scans above horizon at both ends. Source Setup file Frequency sets Observing hours (duplicates not shown) Scan Baseline FAKERA ra1cm2.set 9 2.783 0.000 1236+077 ra1cm2.set 1 2 3 6 7 8 11 13 14 15 16 + 0.347 16.742 1226+023 ra1cm2.set 1 2 3 6 7 8 11 13 14 15 16 + 0.667 51.411 1253-055 ra1cm2.set 1 2 3 6 7 8 11 13 14 15 16 + 0.597 42.278 1228+126 ra1cm2.set 1 2 3 6 7 8 11 13 14 15 16 + 8.722 862.110 ra7mm2.set 30 31 32 0.350 15.750 1156+295 ra1cm2.set 1 2 3 6 7 8 11 13 14 15 16 + 0.617 51.640 EFFECT OF SOLAR CORONA 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) FAKERA 74.5 1236+077 131.5 1226+023 132.1 1253-055 141.6 1228+126 127.0 1156+295 111.1 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