Left: Sums of 16 CW runs at midpoint 07:44 UT with 0.625 Hz resolution. Elevation is 26 deg. No obvious secondary. Assuming the central spike is the secondary results in a far worse orbital fit than not including this data point.
All calculations are based on current system parameters, a target diameter of 700 m, and a nominal spin period of 4 hours. The taxonomy and spin period have not been determined. The size estimate is conservative and based on an absolute magnitude of 18.1 and albedo of 0.20. The spin period estimate is standard for asteroids with H < 22. Under these assumptions of size and spin rate, the predicted bandwidth for an equatorial view is ~17 Hz.
ORBITAL ELEMENTS
EPOCH= 2453895.5 ! 2006-Jun-09.00 (CT) Residual RMS= .44813
EC= .3999009391231627 QR= .9808148220236723 TP= 2453870.74366339
OM= 75.01533689474591 W= 156.1277694188605 IN= 19.44902646137039
A= 1.634421524657197 MA= 11.67735123691641 ADIST= 2.288028227290721
PER= 2.08956 N= .471691407 ANGMOM= .020156894
DAN= 2.16462 DDN= 1.00538 L= 232.3642664
B= 7.7442603 TP= 2006-May-15.2436634
With 120 optical observations spanning 2004-Feb-16 to 2006-May-25, 2004 DC
solution #31 was computed. Formal 3-sigma S/X-band uncertainties are shown below.
Date__(UT)__HR:MN POS_3sigma DOP_S-sig DOP_X-sig RT_delay-sig 2006-May-29 00:00 2.18718207 0.49 1.77 0.001429 2006-May-30 00:00 2.88914017 0.49 1.75 0.001394 2006-May-31 00:00 3.95717044 0.48 1.72 0.001335 2006-Jun-01 00:00 5.53388395 0.46 1.64 0.001235 2006-Jun-02 00:00 7.65045904 0.42 1.51 0.001070 2006-Jun-03 00:00 9.91263088 0.37 1.32 0.000821 2006-Jun-04 00:00 11.3488988 0.31 1.11 0.000520 2006-Jun-05 00:00 11.2335936 0.28 0.99 0.000323 2006-Jun-06 00:00 9.95303667 0.28 1.02 0.000417 2006-Jun-07 00:00 8.34432330 0.31 1.11 0.000595 Units are: arcseconds for POS, Hz for DOP, and seconds for RT.
Date DOY Start TXon TXoff Stop RTT SNR/run May 29 149 0600 0730 1430 1500 45.6 20 May 30 150 1045 1215 1835 1905 39.6 30 Jun 3 154 1000 1130 1910* 1940 25.9 150 Jun 5 156 1000 1145 1430 1500 28.4 130 Jun 6 157 1145 1315 1545 1745 32.7 80 * June 3 (DOY 154) overlaps with Arecibo observations from 1130 to 1315
Date DOY Start TXon TXoff Stop RTT SNR/run Jun 2 153 1000 1050 1300 1300 27.5 3000 Jun 3 154 0930 1030 1315 1330 25.9 3600 Jun 4 155 1000 1115 1230 1300 26.2 3500
ptaylor(aT)astro(dot)cornell(dot)edu 607 351 3482 CELL 607 255 2727 CORNELL 607 255 9002 FAXThe Goldstone Radar Remote Operations Center is at (818) 354-2877.
ptaylor(aT)astro(dot)cornell(dot)edu 787 878 2612 ARECIBO OBSERVATORY x 211 CONTROL ROOM x 374 VSQ ROOM
/export/data2/osod/ops/2004dc/
/share/trabuco4/jplephem/osod/ops/2004dc/PRDX.OUT.s39and:
/share/olda/Ephm/2004DC.PRDX.OUT.s39Arecibo setup/log files are here:
/share/obs4/usr/radar/2004DC/
Date DOY Start TXon TXoff Stop RTT SNR/run May 29 149 0600 0730 1430 1500 45.6 20The primary objective for the May 29 and 30 observations from Goldstone will be the refinement of the orbit ephemeris of 2004 DC. We would like to have the ephemeris accurate as possible leading into the Arecibo observations so we can maximize the time available for high resolution delay-Doppler imaging. Time and ephemeris quality-permitting, it would be good to take some delay-Doppler images to get a size estimate of the target.
Nominal Plan of Attack: 1. CW with a relatively narrowband setup. Measure the echo's bandwidth and Doppler offset. With a nominal diameter and spin period of 700 m and 4 hours, the predicted bandwidth for an equatorial view is ~17 Hz. 2. 10 usec ranging with 127-length code and the original ephemeris solution. 3. 11 usec ranging with 127-length code and the original ephemeris solution. 4. Update the ephemeris solution in OSOD with a Doppler and a range. 5. Continue 11 usec ranging to verify that the new solution is OK. 6. Do 1 usec ranging to refine the ephemeris more. Update the ephemeris again. 7. Go to higher resolution imaging for the rest of the track. The baud will depend on the bandwidth and SNR of the echoes.POINTING MACROS
TX Offsets
Date (UTC) DOY hhmmss RA Dec Macro LHA Dec OSOD
May 29
2006 05 29 149 070000 355.4657 68.5177 A 31
2006 05 29 149 080000 355.5626 68.3317 A
2006 05 29 149 090000 355.6515 68.1443 A -0.0011 -0.0024
2006 05 29 149 100000 355.7322 67.9550 A
2006 05 29 149 110000 355.8050 67.7628 AB
2006 05 29 149 120000 355.8707 67.5672 B
2006 05 29 149 130000 355.9305 67.3675 B -0.0007 -0.0026
2006 05 29 149 140000 355.9861 67.1632 B
2006 05 29 149 150000 356.0393 66.9541 B
CW observations find a bandwidth of ~11 Hz and approximately equal signal strengths in both polarizations.
Target appears to fill only one range gate at 1 us baud using soln 31, but appears to fill two gates using soln 33.
Imaging at 1/8 us baud reveals a hemispherical echo only 5 range gates deep (< 100 m!). This size would imply a spin
period of ~100 minutes to produce the observed bandwidth. The size is also at odds with the absolute magnitude and
would require an albedo > 2. Possibly the absolute magnitude is in error or we have not seen the full extent in the
1/8 us imaging.
Left: Sums of 16 CW runs at midpoint 07:44 UT with 0.625 Hz resolution. Elevation is 26 deg. No obvious secondary.
Assuming the central spike is the secondary results in a far worse orbital fit than not including this data point.
Right: Sums of 20 CW runs at midpoint 14:15 UT with 0.4 Hz resolution. Elevation is 58 deg. No obvious secondary. Assuming the rightmost spike is the secondary results in a far worse orbital fit than not including this data point.
CW Analysis on 07:44 (left) summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
Threshold Minimum : -6.3430389 Hz Threshold Maximum : 3.2904319 Hz Bandwidth of Echo : 9.6334709 Hz Signal-to-Noise : 0.20962128 Radar X-section 1 : 6129.7285 m^2 Radar X-section 2 : 6649.8057 m^2 Radar Albedo 1 : 0.086717919 Radar Albedo 2 : 0.094075507 Radar Albedo Total : 0.18079343 Polarization Ratio : 1.0848451
CW Analysis on 14:15 (right) summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
Threshold Minimum : -5.3398469 Hz Threshold Maximum : 4.7161818 Hz Bandwidth of Echo : 10.056029 Hz Signal-to-Noise : 0.32886416 Radar X-section 1 : 7151.8165 m^2 Radar X-section 2 : 7554.9417 m^2 Radar Albedo 1 : 0.10117751 Radar Albedo 2 : 0.10688056 Radar Albedo Total : 0.20805807 Polarization Ratio : 1.0563668
Date DOY Start TXon TXoff Stop RTT SNR/run May 30 150 1045 1215 1835 1905 39.6 30Ephemeris solution 35 should be pretty good from the astrometry collected yesterday. Start with CW to look for changes in the limb-to-limb bandwidth (to help constrain pole location), check polarization ratio and cross-sections obtained already. Later, attempt 1/8 us imaging again to confirm the size of the target. The signal should be up by 50% compared to the previous day.
POINTING MACROS
TX Offsets
Date (UTC) DOY hhmmss RA Dec Macro LHA Dec OSOD
May 30
2006 05 30 150 120000 357.7388 61.9210 A 35
2006 05 30 150 130000 357.7905 61.6578 A
2006 05 30 150 140000 357.8381 61.3890 A -0.0005 -0.0031
2006 05 30 150 150000 357.8835 61.1141 A
2006 05 30 150 160000 357.9285 60.8330 AB
2006 05 30 150 170000 357.9748 60.5458 B
2006 05 30 150 180000 358.0242 60.2525 B -0.0006 -0.0032
2006 05 30 150 190000 358.0782 59.9537 B
2006 05 30 150 200000 358.1378 59.6497 B
Ephemeris solution 37 was produced using ranging measurements from the 1/8 us imaging of May 29 and May 30.
The range measurements were assigned uncertainties of roughly the echo depth as we remain unconvinced that
we are seeing the true extent of the target in the 1/8 us images.
To check the size of the target, we reverted to a coarser 0.5 us baud setup. 0.5 us imaging clearly shows
an echo depth of 2-3 rg or > 150 m, at least 50% larger than the echo in the 1/8 us imaging.
Right: Sum of 23 CW runs at midpoint 18:19 UT processed with 0.625 Hz resolution. Elevation is 51 deg. Secondary is
the leftmost spike, -0.726 Hz (S-band) from the center of the echo.
NOTE: The SC echo looks much more powerful than the OC, but the polarization ratio is ~1. This is because the
echoes are plotted in terms of the st.dev. of the noise, which is different for each channel. Also, the baseline
for each channel differs. It seems that SC has more background noise (baseline) than OC, but the variability
(st.dev.) does not increase as much, giving the appearance that SC is much stronger though the SNRs are similar.
CW Analysis on 12:32 (left) summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
CW Analysis on 18:19 (right) summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
Right: Sum of 11 CW runs at midpoint 11:00 UT processed with 0.33 Hz resolution. (Azimuth, Elevation) is (37, 72) deg.
Secondary is the leftmost spike in the SC channel, -0.735 Hz (S-band) from the center of the echo.
CW Analysis on 0.25 Hz resolution summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
CW Analysis on 0.33 Hz resolution summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC); Note the drop in SNR,
the factor of two difference in radar albedo and the 0.1 drop in polarization ratio (?!):
Right: Sum of 11 CW runs at midpoint 10:45 UT processed with 0.33 Hz resolution. (Azimuth, Elevation) is (89, 74) deg.
Secondary is possibly the leftmost spike in the SC channel (based on images later), -0.523 Hz (S-band) from the center of the echo.
CW Analysis on 0.25 Hz resolution summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
CW Analysis on 0.33 Hz resolution summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC); Note the drop in SNR,
the factor of two difference in radar albedo and the 0.1 drop in polarization ratio (?!):
The similarity of these frames to the final frames of the Jun 02 Arecibo mosaic implies an orbital period for the secondary of ~22 hours.
The remainder of the track was lost to a transmitter problem.
POINTING MACROS
Right: Sum of 7 CW runs at midpoint 19:05 UT processed with 0.8 Hz resolution. Elevation is 33 deg.
Secondary is the rightmost spike, 1.183 Hz (S-band) from the center of the echo.
CW Analysis on 12:40 (left) summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
CW Analysis of 19:05 (right) summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
Right: Sum of 9 CW runs at midpoint 11:15 UT processed with 0.33 Hz resolution. (Azimuth, Elevation) is (150, 71) deg.
Secondary is possibly the leftmost spike in the SC channel, -0.526 Hz (S-band) from the center of the echo.
CW Analysis on 0.25 Hz resolution summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC); Note the drop in SNR,
the factor of two difference in radar albedo and the 0.1 drop in polarization ratio (?!):
CW Analysis on 0.33 Hz resolution summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
The remainder of the track was lost due to a turbine/transmitter problem.
POINTING MACROS
Right: Sum of 12 CW runs at midpoint 14:24 UT processed with 0.625 Hz resolution. Elevation is 39 deg.
Secondary is the rightmost spike, 0.481 Hz (S-band) from the center of the echo.
CW Analysis on 11:52 (left) summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
CW Analysis of 14:24 (right) summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
POINTING MACROS
Right: Sum of 9 CW runs at midpoint 15:40 UT processed with 0.625 Hz resolution. Elevation is 28 deg.
Secondary is the rightmost peak, 1.085 Hz (S-band) from the center of the echo.
CW Analysis on 13:21 (left) summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
CW Analysis on 15:40 (right) summed spectrum using 300 m diameter spheroid (1 = OC, 2 = SC):
I seemed to have goofed up when updating the ephemeris for Arecibo. When going from
s31 to s37 I know I made mistakes, and I must have iterated and not noted the change
in solution number (as in doing, say 'iter 29' instead of 'iter 31', realizing the mistake,
and going back and doing 'iter 31'). I realized that after adding two range corrections
from Arecibo on 2006 Jun 02, the new solution I produced "s39" had good residuals, but the
predicts were actually WORSE than the previous solution. Mike Nolan found that the true
solution number we were on was s45, not s39. I chose not to apply the correction from Jun
03 at Arecibo due to confusion about whether I was correcting the right ephemeris or not.
The correction from Goldstone on Jun 03 was used to produce s47 at Arecibo.
At Goldstone, the Jun 02 corrections from Arecibo were used to produce s39. The Jun 03
correction from Goldstone was used to produce s41.
It seems that the ephemeris was never really nailed like I had hoped (images never right
at the loopback/closed loop range gate). I wonder if it is due to my ephemeris goof up
at Arecibo. I know that up to s37 on stealth at Goldstone is good and I trust it. Beyond
that, the solutions on utuado and s39 and s41 on stealth may have been corrupted by my
goof up.
OSOD Entries
Left: Sum of 15 CW runs at midpoint 12:32 UT processed with 0.625 Hz resolution. Elevation is 54 deg. Secondary is
the central spike, -0.310 Hz (S-band) from the center of the echo. The bandwidth of the primary has increased by ~2 Hz
(X-band).
Threshold Minimum : -6.9326488 Hz
Threshold Maximum : 5.8906230 Hz
Bandwidth of Echo : 12.823272 Hz
Signal-to-Noise : 0.86000565
Radar X-section 1 : 14532.226 m^2
Radar X-section 2 : 14562.021 m^2
Radar Albedo 1 : 0.20558894
Radar Albedo 2 : 0.20601046
Radar Albedo Total : 0.41159939
Polarization Ratio : 1.0020503
Threshold Minimum : -5.9369795 Hz
Threshold Maximum : 6.1822708 Hz
Bandwidth of Echo : 12.119250 Hz
Signal-to-Noise : 1.0978323
Radar X-section 1 : 16296.332 m^2
Radar X-section 2 : 16345.869 m^2
Radar Albedo 1 : 0.23054594
Radar Albedo 2 : 0.23124674
Radar Albedo Total : 0.46179268
Polarization Ratio : 1.0030398
Sum of 80 runs at 1/8 us baud in OC channel using s35 (left) and sum of 76 runs using s37 (right). Pixels are 18.75 m x 1 Hz.
Same, but for the SC channel.
2006 Jun 02 - DOY 153 - Arecibo
Date DOY Start TXon TXoff Stop RTT SNR/run
Jun 2 153 1000 1050 1300 1300 27.5 3000
Left: Sum of 11 CW runs at midpoint 11:00 UT processed with 0.25 Hz resolution.
Threshold Minimum : 198.50561 Hz
Threshold Maximum : 202.46540 Hz
Bandwidth of Echo : 3.9597903 Hz
Signal-to-Noise : 110.71398
Radar X-section 1 : 16182.945 m^2
Radar X-section 2 : 12772.756 m^2
Radar Albedo 1 : 0.22894184
Radar Albedo 2 : 0.18069753
Radar Albedo Total : 0.40963937
Polarization Ratio : 0.78927263
Threshold Minimum : 198.40370 Hz
Threshold Maximum : 202.46104 Hz
Bandwidth of Echo : 4.0573449 Hz
Signal-to-Noise : 57.289300
Radar X-section 1 : 8580.2188 m^2
Radar X-section 2 : 5941.9350 m^2
Radar Albedo 1 : 0.12138526
Radar Albedo 2 : 0.084061184
Radar Albedo Total : 0.20544645
Polarization Ratio : 0.69251556
Mosaic showing the motion of the secondary over 1.8 hours. Each frame is the average of five individual runs.
Range increases downward, frequency increases to the right. Time increases from left to right and top to bottom.
Resolution is 7.5 m x 0.05 Hz.
2006 Jun 03 - DOY 154 - Arecibo
Date DOY Start TXon TXoff Stop RTT SNR/run
Jun 3 154 0930 1030 1315 1330 25.9 3600
Left: Sum of 11 CW runs at midpoint 10:45 UT processed with 0.25 Hz resolution.
Threshold Minimum : 198.51280 Hz
Threshold Maximum : 202.65921 Hz
Bandwidth of Echo : 4.1464059 Hz
Signal-to-Noise : 183.04670
Radar X-section 1 : 21486.242 m^2
Radar X-section 2 : 15616.990 m^2
Radar Albedo 1 : 0.30396815
Radar Albedo 2 : 0.22093521
Radar Albedo Total : 0.52490336
Polarization Ratio : 0.72683673
Threshold Minimum : 198.35284 Hz
Threshold Maximum : 202.65814 Hz
Bandwidth of Echo : 4.3053033 Hz
Signal-to-Noise : 101.18017
Radar X-section 1 : 12331.784 m^2
Radar X-section 2 : 8105.5634 m^2
Radar Albedo 1 : 0.17445906
Radar Albedo 2 : 0.11467027
Radar Albedo Total : 0.28912933
Polarization Ratio : 0.65729040
Sums of 5 images each with resolution 7.5 m x 0.05 Hz.
2006 Jun 03 - DOY 154 - Goldstone
Date DOY Start TXon TXoff Stop RTT SNR/run
Jun 3 154 1000 1130 1910 1940 25.9 150
Because of the small size of the target, we will forego the interferometry idea.
Instead, we should have Goldstone and Arecibo do their own transmitting and
receiving and collect as much data on this binary system as possible. At X-band,
the secondary should be ~0.75 Hz wide.
Proposed Sequence:
0. Configure using ephemeris s39
1. Start the track with 10 CW runs
2. Image at 1/8 us for as much of the track as possible
3. End with 10 CW runs
We have noticed differences in the strength of the CW runs from the beginning to
the end of the previous two tracks, so we should try it again on this track to
see if the pattern continues. The target should be 5x stronger than the
previous dates and should not require more than 10 runs for analysis. The main
goal is to image the system for as long as possible. However, we should not be
shy about taking breaks to take boresights on nearby radio sources (i.e, within
1 deg). The nominal period of the primary is ~3 hr given the observed size and
bandwidth, so we should easily cover a full rotation (or two) with the 1/8 us
imaging.
TX Offsets
Date (UTC) DOY hhmmss RA Dec Macro LHA Dec OSOD
2006 06 03 154 110000 3.2932 17.6221 A 39
2006 06 03 154 120000 3.3280 16.9697 A
2006 06 03 154 130000 3.3586 16.3145 A -0.0002 -0.0047
2006 06 03 154 140000 3.3860 15.6567 A
2006 06 03 154 150000 3.4116 14.9964 AB
2006 06 03 154 160000 3.4368 14.3338 B
2006 06 03 154 170000 3.4630 13.6693 B -0.0002 -0.0047
2006 06 03 154 180000 3.4915 13.0034 B
2006 06 03 154 190000 3.5235 12.3366 B
Left: Sum of 12 CW runs at midpoint 12:40 UT processed with 0.625 Hz resolution. Elevation is 51 deg.
Secondary is the leftmost spike, -0.706 Hz (S-band) from the center of the echo.
Threshold Minimum : -6.2049545 Hz
Threshold Maximum : 8.4218155 Hz
Bandwidth of Echo : 14.626770 Hz
Signal-to-Noise : 4.3112256
Radar X-section 1 : 14221.696 m^2
Radar X-section 2 : 14454.277 m^2
Radar Albedo 1 : 0.20119584
Radar Albedo 2 : 0.20448619
Radar Albedo Total : 0.40568204
Polarization Ratio : 1.0163540
Threshold Minimum : -6.8110368 Hz
Threshold Maximum : 7.8212659 Hz
Bandwidth of Echo : 14.632303 Hz
Signal-to-Noise : 3.4681510
Radar X-section 1 : 7176.2589 m^2
Radar X-section 2 : 6991.4963 m^2
Radar Albedo 1 : 0.10152330
Radar Albedo 2 : 0.098909440
Radar Albedo Total : 0.20043274
Polarization Ratio : 0.97425364
"Movies" of 1/8 us imaging in LCP/OC (left) and RCP/SC (right).
2006 Jun 04 - DOY 155 - Arecibo
Date DOY Start TXon TXoff Stop RTT SNR/run
Jun 4 155 1000 1115 1230 1300 26.2 3500
Left: Sum of 9 CW runs at midpoint 11:15 UT processed with 0.25 Hz resolution. (Azimuth, Elevation) is (150, 71) deg.
Threshold Minimum : 198.26121 Hz
Threshold Maximum : 202.20321 Hz
Bandwidth of Echo : 3.9420028 Hz
Signal-to-Noise : 84.460029
Radar X-section 1 : 11008.439 m^2
Radar X-section 2 : 9888.4222 m^2
Radar Albedo 1 : 0.15573755
Radar Albedo 2 : 0.13989256
Radar Albedo Total : 0.29563011
Polarization Ratio : 0.89825835
Threshold Minimum : 198.17079 Hz
Threshold Maximum : 202.19737 Hz
Bandwidth of Echo : 4.0265813 Hz
Signal-to-Noise : 50.126889
Radar X-section 1 : 6673.6711 m^2
Radar X-section 2 : 5380.4356 m^2
Radar Albedo 1 : 0.094413133
Radar Albedo 2 : 0.076117592
Radar Albedo Total : 0.17053072
Polarization Ratio : 0.80621827
2006 Jun 05 - DOY 156 - Goldstone
Date DOY Start TXon TXoff Stop RTT SNR/run
Jun 5 156 1000 1130 1430 1500 28.4 130
The plan for this track is the same as for the June 3 track. I have updated
the ephemeris on stealth to solution 41 using a range correction from the
June 3 1/8 us data.
0. Configure using ephemeris s41
1. Start the track with 10 CW runs
2. Image at 1/8 us for as much of the track as possible
3. End with 10 CW runs
TX Offsets
Date (UTC) DOY hhmmss RA Dec Macro LHA Dec OSOD
2006 06 05 156 120000 5.3506 -13.1599 A 41
2006 06 05 156 130000 5.3746 -13.7055 A -0.0002 -0.0043
2006 06 05 156 140000 5.3958 -14.2454 A
Left: Sum of 11 CW runs at midpoint 11:52 UT processed with 0.625 Hz resolution. Elevation is 22 deg.
Secondary is the central spike, -0.374 Hz (S-band) from the center of the echo.
Threshold Minimum : -6.1773628 Hz
Threshold Maximum : 7.5485529 Hz
Bandwidth of Echo : 13.725916 Hz
Signal-to-Noise : 2.7584822
Radar X-section 1 : 13138.515 m^2
Radar X-section 2 : 13264.241 m^2
Radar Albedo 1 : 0.18587196
Radar Albedo 2 : 0.18765063
Radar Albedo Total : 0.37352259
Polarization Ratio : 1.0095693
Threshold Minimum : -5.9050081 Hz
Threshold Maximum : 7.2430427 Hz
Bandwidth of Echo : 13.148051 Hz
Signal-to-Noise : 1.9245024
Radar X-section 1 : 9503.3922 m^2
Radar X-section 2 : 9707.6326 m^2
Radar Albedo 1 : 0.13444550
Radar Albedo 2 : 0.13733491
Radar Albedo Total : 0.27178040
Polarization Ratio : 1.0214913
Sum of 110 runs at 1/8 us baud in OC channel.
2006 Jun 06 - DOY 157 - Goldstone
Date DOY Start TXon TXoff Stop RTT SNR/run
Jun 6 157 1145 1315 1545 1745 32.7 80
0. Configure using ephemeris s41
1. Start the track with 10 CW runs
2. Image at 1/4 us to try and find the secondary quickly
3. Continue with 1/4 us or switch to 1/2 or 1/8 us depending on results
4. End with 10 CW runs
TX Offsets
Date (UTC) DOY hhmmss RA Dec Macro LHA Dec OSOD
2006 06 06 157 130000 6.2464 -25.2478 A 41
2006 06 06 157 140000 6.2650 -25.6706 A
2006 06 06 157 150000 6.2821 -26.0871 A -0.0001 -0.0038
2006 06 06 157 160000 6.2989 -26.4972 A
2006 06 06 157 170000 6.3165 -26.9008 A
Left: Sum of 10 CW runs at midpoint 13:21 UT processed with 0.4 Hz resolution. Elevation is 24 deg.
Secondary is the rightmost peak, 0.603 Hz (S-band) from the center of the echo.
Threshold Minimum : -5.5392167 Hz
Threshold Maximum : 6.7829709 Hz
Bandwidth of Echo : 12.322188 Hz
Signal-to-Noise : 1.8841006
Radar X-section 1 : 16394.996 m^2
Radar X-section 2 : 16425.674 m^2
Radar Albedo 1 : 0.23194175
Radar Albedo 2 : 0.23237575
Radar Albedo Total : 0.46431750
Polarization Ratio : 1.0018712
Threshold Minimum : -6.0160767 Hz
Threshold Maximum : 6.9352306 Hz
Bandwidth of Echo : 12.951307 Hz
Signal Power : 256.51088 arb. units
Noise Power : 156.29087 arb. units
Signal Power : 5.5760040e-21 Watts = 1.5542816 Jansky
Noise Power : 3.3974330e-21 Watts = 0.94701645 Jansky
Signal-to-Noise : 1.6412403
Radar X-section 1 : 14322.184 m^2
Radar X-section 2 : 14642.530 m^2
Radar Albedo 1 : 0.20261745
Radar Albedo 2 : 0.20714943
Radar Albedo Total : 0.40976688
Dielectric Constant : 6.9549639 (only applies for small polarization ratios)
Polarization Ratio : 1.0223671
Radar Astrometry
Initial ephemeris solution for radar observations at Goldstone on 2006 May 29 was s31.
We added corrections for the Doppler shift in the CW data and an unambiguous range
determination to produce s33. We added a correction from 1 us ranging to produce s35.
Corrections from the 1/8 us imaging on May 29 and 30 produced s37.
2006 05 29 07:40:00 P 601427.0D0 0.5 8560.D6 -14 -14 Taylor, P., Margot, J.L.
Correction of -1.5 Hz to soln 31 from 16 CW runs with 0.488 Hz res'n.
Bandwidth is about 11 Hz.
2006 05 29 08:40:00 R 46.94504797 10.0 8560.D6 -14 -14 Taylor, P., Margot, J.L.
Correction of -351 us to soln 31 from 4 runs each at 10 and 11 us.
2006 05 29 10:00:00 R 46.60867061 1.0 8560.D6 -14 -14 Taylor, P., Margot, J.L.
Correction of +6 us to soln 33 based on 12 runs at 1 us baud.
Echo appears in a single range gate.
2006 05 29 12:20:00 R 46.02346559 0.5 8560.D6 -14 -14 Taylor, P., Margot, J.L.
Based on 110 runs at 1/8 us, assume CoM at TE, 4 rg from LE.
Correction of +0.5 us to soln 35.
2006 05 30 14:00:00 R 39.90208722 0.5 8560.D6 -14 -14 Taylor, P., Margot, J.L.
Based on 61 runs at 1/8 us, assume CoM at TE, 4 rg from LE.
Correction of -1.125 us to soln 35.
2006 06 02 11:10:00 R 27.56700660 0.5 2380.D6 -1 -1 Taylor, P., Nolan, M.
Based on 10 runs at 0.05 us, assume CoM at TE.
Correction of -16.2 us to soln 37.
2006 06 02 12:30:00 R 27.42772497 0.5 2380.D6 -1 -1 Taylor, P., Nolan, M.
Based on 10 runs at 0.05 us, assume CoM at TE.
Correction of -17.25 us to soln 37.
=== NOT INCLUDED ===
2006 06 03 11:00:00 R 25.90622443 0.25 2380.D6 -1 -1 Taylor, P., Nolan, M.
Based on 8 runs at 0.05 us, assume CoM at TE.
Correction of -39.4 us to (bad) soln 39.
=== NOT INCLUDED ===
2006 06 03 15:10:00 R 25.80931750 0.25 8560.D6 -14 -14 Taylor, P.
Based on 10 runs at 1/8 us, assume CoM at TE.
Correction of +0.5 us to soln 39.
Motion of 2004DC during this apparition
The first Goldstone observations are on 2006 May 29 UT (MJD 53884).
Close approach is on 2006 June 3 (MJD 53889). The final Goldstone
observations are on 2006 June 6 (MJD 53892) after 95 degrees of sky
motion. The sky motion over the Arecibo observations from 2006 June
2-4 is 32 degrees.
Below is the motion of 2004 DC from May 27 to June 8 in distance
from Earth, right ascension, and declination. The observing times for
Goldstone are marked by the \\\ hatching, and the observing times for
Arecibo are marked by the /// hatching. Note the overlap on June 3
(MJD 53889) available for attempting interferometry.
Goldstone Setups
CW setup
--------
TX polarization RCP
RCV polarization LCP
Frequencies: 2
Dwell: 20 seconds
Bandwidth: 4000 Hz
Sampling interval: 2500 x 0.1 usec
VME FFT for PSD files: 2048 for 1.95-Hz resolution
Possible ranging setups:
---------------------------------------------------------------------------
127 x 64 10-usec single sample, 12.3-Hz resolution.
baud 10 usec
code 127
gates 127
FFT 64
CLT 2 (VME)
ncoh 1
bandwidth 787.4 Hz
resolution 12.30 Hz
TXOFF +100 Hz -> echo will be centered at +8.1 bins or in bin 32 + 8.1 = 40
---------------------------------------------------------------------------
127 x 64 11-usec single sample, 11.2-Hz resolution.
baud 11 usec
code 127
gates 127
PRP 1397
FFT 64
CLT 2 (VME)
ncoh 1
bandwidth 715.8 Hz
resolution 11.18 Hz
TXOFF +100 Hz --> echo will be centered at +8.9 bins or in bin 32 + 8.9 = 41
-------------------------------------------------------------------------
127 x 64 1-usec single sample
------------------------------
baud 1 usec
code 127
gates 127
PRP 127
FFT 64
CLT 4
ncoh 15
bandwidth 525 Hz
resolution 8.2 Hz
TXOFF +100 -> echo would be centered at +12.2 bins or in bin 32 + 12.2 = 44
-------------------------------------------------------------------------------
0.125-usec ranging
------------------
setup JX1XS001 revised
baud 0.125 usec
code 127
gates 127
FFT 64
ncoh 984
bandwidth 64.016384 Hz
resolution 1.000256 Hz
TXOFF Depends on bandwidth
-------------------------------------------------------------------------------
0.125-usec ranging - for May 29
------------------
setup JX1XS001 revised
baud 0.125 usec
code 127
gates 127
FFT 64
ncoh 492
bandwidth 128.03277 Hz
resolution 2.0005 Hz on VME, 1 Hz on PFS
TXOFF +10 Hz
PFS CLT gate 24
-------------------------------------------------------------------------------
0.125-usec ranging - for May 30
------------------
setup JX1XS001 revised
baud 0.125 usec
code 127
gates 127
FFT 64
ncoh 984
bandwidth 128.03277 Hz
resolution 1.0003 Hz
TXOFF +20 Hz, +15 Hz
PFS CLT gate
-------------------------------------------------------------------------------
0.5-usec ranging - for May 30
----------------
setup
baud 0.5 usec
code 127
gates 127
FFT 64
ncoh 49
bandwidth 321.38840 Hz
resolution 5.0217 Hz
TXOFF +15 Hz
PFS CLT gate not recorded
_____________________________________________________________________
POSSIBLE RANGING SETUPS: (code=127, FFT=64, single-pol'n)
These are from JX, w/ max-band (min-acc) options from Ray Jurgens.
Currently configured for 5-sec records.
_______________________________________________________________________
Setup Baud RP 1-acc 1-acc
usec m usec band res acc band res
_______________________________________________________________________
JX1XS110 11.000 1650 1397.0 715.8 11.2 2 358 5.6
JX1XS070 7.000 1050 889.0 1124.9 17.6 3 375 5.9
JX1XS020 2.000 300 254.0 3937.0 61.5 12 328 5.1
4 984 15.4
JX1XS010 1.000 150 127.0 7874.0 123.0 41 192 3.0
8 984 15.4
JX1XS005 0.500 75 63.5 15748.0 246.1 123 128 2.0
15 1050 16.4
JX1XS002 0.250 37.5 31.75 31496.1 492.1 492 64 1.0
30 1050 16.4
JX1XS001 0.125 18.75 15.875 62992.1 984.3 1970 32 0.5
60 1050 16.4
_______________________________________________________________________