1999 JM8 Planning
Near-Earth asteroid 1999 JM8 was discovered on 1999 May 13 by the MIT/Lincoln Labs Near-Earth asteroid (LINEAR) search program. The asteroid's absolute magnitude of 15.0 suggests that it is between 3 and 6 km in diameter and that is among the largest Earth-crossing objects. Photometric observations by Lenka Sarounova in the Czech Republic indicate that it has an unusally long rotation period that is close to one week. We know nothing else about the physical properties of this object.
1999 JM8 approaches within 0.057 AU of Earth on 1999 July 30, providing an outstanding opportunity to study its physical properties. Our SNR estimates suggest that the echoes may be comparable to the strongest we have ever detected from an asteroid. We expect to obtain high-resolution images that can be used to reconstruct a detailed model of the asteroid's three-dimensional shape.
These will be combined Goldstone and Arecibo observations. The Goldstone observations start on July 18 and conclude on August 8; Arecibo observations are scheduled for August 1-6 and August 9.
The Goldstone strategy will be to start with CW, detect the echo and measure the Doppler correction, and then update the orbit. We'll measure the asteroid's basic radar properties such as its radar cross section, SC/OC polarization ratio, and Doppler dispersion, and then we'll go from coarse-resolution ranging to high-resolution imaging as soon as possible. The echoes should be strong enough to image with 0.125 us resolution.
THERE WAS NO DISCOVERY ANNOUNCEMENT FOR THIS OBJECT!
1999 JM8 was discovered by the MIT/Lincoln Labs (LINEAR) search program on May 13 and
subsequently it was realized that LINEAR had also detected the object on 1999 April 10. The
Minor Planet Center never issued an electronic circular, but ultimately Gareth Williams
released the announcement below indicating that this object was originally discovered
on 1990 April 27, designated 1990 HD1, but then lost until LINEAR recovered it.
M.P.E.C. 1999-N15 Issued 1999 July 9, 14:38 UT
The Minor Planet Electronic Circulars contain information on unusual
minor planets and routine data on comets. They are published
on behalf of Commission 20 of the International Astronomical Union by the
Minor Planet Center, Smithsonian Astrophysical Observatory,
Cambridge, MA 02138, U.S.A.
BMARSDEN@CFA.HARVARD.EDU or GWILLIAMS@CFA.HARVARD.EDU
URL http://cfa-www.harvard.edu/iau/mpc.html ISSN 1523-6714
1999 JM8
Observations:
J99J08M C1999 07 08.47847 13 38 52.83 +49 49 56.4 14.9 V 360
J99J08M C1999 07 08.48003 13 38 52.52 +49 49 59.8 360
J99J08M C1999 07 08.48160 13 38 52.22 +49 50 03.1 360
Observer details:
360 Kuma Kogen. Observer A. Nakamura. 0.60-m f/6.0 Ritchey-Chretien + CCD.
Orbital elements:
1999 JM8 = 1990 HD1 PHA 0.018D
Epoch 1999 Aug. 10.0 TT = JDT 2451400.5 Nakano
M 3.72490 (2000.0) P Q
n 0.21927331 Peri. 165.97219 +0.50650893 +0.84532897
a 2.7236139 Node 134.13135 -0.81215543 +0.53391397
e 0.6436762 Incl. 13.69304 -0.28957254 -0.01883625
P 4.49 H 15.1 G 0.15 U 1
...
Ephemeris:
1999 JM8 a,e,i = 2.72, 0.64, 14 q = 0.9705
Date TT R. A. (2000) Decl. Delta r Elong. Phase V
1999 07 01 13 53.81 +46 10.5 0.210 1.022 85.6 82.6 14.6
1999 07 06 13 45.07 +48 25.2 0.179 1.003 80.4 89.4 14.5
1999 07 11 13 30.57 +51 32.7 0.148 0.987 74.5 97.2 14.4
1999 07 16 13 02.13 +56 07.0 0.117 0.977 67.2 106.5 14.4
1999 07 21 11 52.40 +62 28.2 0.088 0.971 57.3 118.3 14.5
1999 07 26 08 45.70 +64 27.0 0.065 0.971 45.1 132.2 15.0
1999 07 31 05 42.49 +43 18.7 0.057 0.975 44.6 133.0 14.8
1999 08 05 04 34.49 +16 20.3 0.069 0.985 62.9 113.5 13.7
1999 08 10 04 06.28 -00 00.6 0.094 0.999 78.3 96.4 13.4
1999 08 15 03 51.34 -09 07.0 0.123 1.018 88.7 84.4 13.5
1999 08 20 03 41.68 -14 40.0 0.153 1.040 96.4 75.2 13.7
1999 08 25 03 34.24 -18 23.2 0.184 1.067 102.7 67.6 13.9
1999 08 30 03 27.58 -21 03.8 0.215 1.096 108.2 61.1 14.1
1999 09 04 03 20.91 -23 04.9 0.245 1.128 113.4 55.1 14.3
1999 09 09 03 13.81 -24 37.9 0.275 1.163 118.2 49.7 14.5
1999 09 14 03 06.11 -25 47.9 0.306 1.200 122.9 44.8 14.6
1999 09 19 02 57.86 -26 37.5 0.337 1.238 127.3 40.2 14.8
1999 09 24 02 49.19 -27 08.0 0.369 1.278 131.4 36.1 14.9
1999 09 29 02 40.32 -27 20.6 0.404 1.319 135.1 32.4 15.1
1999 10 04 02 31.45 -27 16.1 0.440 1.361 138.4 29.2 15.3
1999 10 09 02 22.86 -26 55.7 0.478 1.403 141.0 26.6 15.4
1999 10 14 02 14.79 -26 20.7 0.520 1.446 142.8 24.7 15.6
1999 10 19 02 07.48 -25 32.8 0.565 1.490 143.7 23.3 15.8
1999 10 24 02 01.07 -24 34.4 0.614 1.534 143.8 22.5 16.0
1999 10 29 01 55.64 -23 27.5 0.666 1.577 143.1 22.2 16.3
1999 11 03 01 51.23 -22 14.2 0.722 1.621 141.7 22.3 16.5
1999 11 08 01 47.83 -20 56.3 0.781 1.665 139.6 22.7 16.8
1999 11 13 01 45.42 -19 35.1 0.845 1.709 137.1 23.2 17.0
1999 11 18 01 43.96 -18 12.0 0.912 1.752 134.3 23.8 17.2
1999 11 23 01 43.38 -16 48.1 0.983 1.795 131.3 24.4 17.5
1999 11 28 01 43.59 -15 24.4 1.057 1.838 128.1 25.0 17.7
1999 12 03 01 44.52 -14 01.2 1.135 1.881 124.8 25.5 17.9
1999 12 08 01 46.11 -12 39.1 1.216 1.924 121.5 25.9 18.1
1999 12 13 01 48.29 -11 18.5 1.300 1.966 118.1 26.2 18.3
1999 12 18 01 51.01 -09 59.4 1.386 2.007 114.7 26.5 18.5
1999 12 23 01 54.21 -08 42.3 1.475 2.049 111.3 26.6 18.7
1999 12 28 01 57.83 -07 27.1 1.567 2.090 107.9 26.6 18.9
2000 01 02 02 01.83 -06 13.9 1.660 2.130 104.5 26.5 19.0
2000 01 07 02 06.18 -05 02.8 1.755 2.170 101.1 26.4 19.2
2000 01 17 02 15.76 -02 46.7 1.949 2.249 94.4 25.9 19.5
2000 01 27 02 26.34 -00 39.1 2.147 2.327 87.8 25.0 19.7
2000 02 06 02 37.72 +01 20.2 2.346 2.402 81.2 23.9 20.0
2000 02 16 02 49.75 +03 11.3 2.545 2.476 74.7 22.6 20.2
2000 02 26 03 02.31 +04 54.0 2.742 2.548 68.4 21.2 20.4
2000 03 07 03 15.29 +06 28.7 2.933 2.619 62.0 19.6 20.5
Gareth V. Williams (C) Copyright 1999 MPC M.P.E.C. 1999-N15
H = 15 ==> diameter = 3.1 km; assume period = 12 days (!), equatorial view, radar albedo
= 0.1. Assume optimal parameters for Goldstone and Tsys = 31 K, sensitivity = 7.3 K/Jy
for Arecibo. Tracks in bold are those scheduled for observations, where the times
shown and SNR/date correspond to the actual tracks.
------------GOLDSTONE---------- -------------ARECIBO-----------
Max Max
Dat Run UTC Dat Run UTC
Date RA Decl Delta Runs SNR SNR Window Runs SNR SNR Window
1999 7 18 190 58 0.105 190 1400 100 19:55-07:15 0 0 0 -
1999 7 20 183 61 0.094 23 720 160 02:30-03:40 0 0 0 -
1999 7 21 178 62 0.088 22 860 180 17:40-18:45 0 0 0 -
1999 7 23 164 65 0.078 27 1600 290 00:30-01:40 0 0 0 -
1999 7 24 154 65 0.073 82 3300 350 16:55-20:15 0 0 0 -
1999 7 27 119 62 0.062 41 4100 640 01:30-02:55 0 0 0 -
1999 7 28 108 59 0.059 56 5500 730 17:10-19:00 0 0 0 -
1999 7 31 86 43 0.057 92 8100 850 17:00-19:55 0 0 0 -
1999 8 1 80 37 0.058 132 9400 810 11:45-16:00 53 47000 6400 12:17-14:00
1999 8 2 76 32 0.060 327 12000 720 10:30-21:53 72 71000 8400 11:35-14:00
1999 8 3 73 26 0.062 302 10000 620 10:24-21:23 82 66000 7200 11:09-13:59
1999 8 4 71 21 0.066 277 7900 520 10:24-20:53 65 48000 6000 11:00-13:44
1999 8 5 68 16 0.069 254 6200 420 10:24-20:30 65 41000 5000 11:00-13:29
1999 8 6 66 12 0.074 233 4800 350 10:24-20:06 20 18000 4100 12:15-13:05
1999 8 7 65 9 0.078 35 1600 280 16:35-18:05 51 22000 3300 10:35-12:54
1999 8 8 64 5 0.083 173 3200 240 11:20-19:20 42 16000 2600 10:35-12:35
1999 8 9 62 2 0.089 180 2200 180 10:24-19:11 25 10000 2000 10:43-12:00
1999 8 10 61 0 0.094 167 1700 140 10:24-18:53 22 5600 1300 10:48-11:48
- - - - - - - - - -
From Lenka Sarounova (1999 July 6):
"I have observed it on 4 nights between July 3-6 and probably less than half
a cycle is covered. The amplitude seems to be more than 0.6 mag.
...More than 7 days?"
- - - - - - - - - -
From Michael Hicks (1999 July 8):
"I am happy to report that we were able to observe 1999 JM8
with SpectroCam 10 on the 200-inch on Palomar the night of July 5 UT.
The observers were Martha Hanner, Tom Haward, and myself. Bill Owen
got near simultaneus R-band photometry from Table Mountain the same
evening. IR imaging from 8-12 microns. No real reductions yet but
it seemed 1999 JM8 was about twice as bright as expected...
I'll try to get colors and LC next week in Arizona, but that
depends on the monsoon!"
- - - - - - - - - -
From Lenka Sarounova (1999 July 15):
"I have four more nights of 1998 JM8 (July 11, 13, 14, 15) with preliminary
linkage only, but the weather should be more promising in next days to
get better calibrations. ...It is sure the period can be very long, more than
some 13 days (the time span of our observations is only 12 days with 5 days
interruption). I cannot exclude it is half of that value (7.3 d)..."
- - - - - - - - - -
From Petr Pravec (1999 July 16):
"I have looked briefly at Lenka's and Yura Krugly's data and believe that the
period showed in the lightcurve is 12 or 13 days. I will have
a more detailed look later today and will let you know then, but I
consider a 7 day period not very likely. We shall also
prepare a www page showing a preliminary lightcurve. In any case, it is
likely to be an object in a complex rotational state and you will certainly
want to cover it extensively enough to describe it. The lightcurve period
can be related to the excited rotational state in a complex way."
- - - - - - - - - -
From Petr Pravec (1999 July 17):
"I have looked in some detail at the lightcurve data obtained by Lenka
(9 nights) and Yura (2 nights) from 1999 July 3.0 to 15.9...
The data show a period of (7.6 +/- 0.2) d. This period corresponds to
reccurence of deep minima (ampl. >0.6 mag) in the lightcurve. The minima
is the most prominent feature apparent there. We have, however, detected
only two of them, on July 4.9 and 12.5. If these two minima correspond
to opposite views of the asteroid, that is likely, then the detected period
is a half of the true period which is then 15.2 d with an error possibly
greater than 1 day (considering possible deviations of the lightcurve from
symmetry). Since the available data cover interval shorter than this period,
this derivation relies on the assumed symmetry (dominance of even harmonics)
in the lightcurve. A shorter period of about 13 days I suggested
earlier doesn't seem likely now, since it requires too asymmetric
shape of the lightcurve and some assumptions which are unlikely to be
held in this case.
The mean, absolute R magnitude is (15.5 +/- 0.5) mag for G=0.15 +/- 0.2.
Assuming V-R=0.4, the mean absolute V magnitude is H=15.9 +/- 0.5.
Note that the error is mostly due to the large phase angle (about 90 deg)
and it will not be lessened when a final calibration is available.
There are some features in the lightcurve which indicate that it is
not a single periodic; a plausible explanation is that the object is
in a complex rotation..."
- - - - - - - - - -
From Petr Pravec (1999 July 18):
"Lenka has obtained and reduced two more nights for 1999 JM8 and made
a new calibration. The available lightcurve data now cover 13 nights
from 1999 July 3.0 to 17.9.
With the nearly 15-d interval covered, it is now possible to derive the
period directly (rather than indirectly by assuming a symmetry of a
shorter lightcurve as I did yesterday). The best fit period
is P=(14.1 +/- 0.5) d. This value is somewhat shorter than but consistent
with that I reported yesterday (15.2 d with error possibly greater than 1 d).
The lightcurve is double peaked, somewhat asymmetric, amplitude >0.6 mag.
There are some features suggesting a complex rotation. The absolute
magnitude estimate which I made yesterday remains unchanged."
- - - - - - - - - -
From Petr Pravec (1999 July 23):
"If the object is 5 km in diameter as your observations indicate,
then its mean, absolute magnitude H=15.9 +/- 0.5 (still my best
estimate) indicates a very dark geometric albedo of 0.03 (+0.02/-0.01).
We have made visual observations on a few more nights, and there are also
visual data by Mike Hicks that I will include as well...
My best estimate for the apparent rotation
period is still (14.1 +/- 0.5) d..."
UTC PDT
UTC UTC TRANSMIT WINDOW TRANSMIT WINDOW
1999 1999 START STOP START STOP
DOY Date hhmm-hhmm hhmm-hhmm DURATION
199 Jul 18 1955-0715 Sun Jul 18 1255-0015 11:20
201 Jul 20 0230-0340 Mon Jul 19 1930-2040 1:10
202 Jul 21 1740-1845 Wed Jul 21 1040-1145 1:05
204 Jul 23 0030-0140 Thu Jul 22 1730-1840 1:10
205 Jul 24 1655-2015 Sat Jul 24 0955-1315 3:20
208 Jul 27 0130-0255 Mon Jul 26 1830-1955 1:25
209 Jul 28 1710-1900 Wed Jul 28 1010-1200 1:50
212 Jul 31 1700-1955 Sat Jul 31 1000-1255 2:55
213 Aug 1 1145-1600 Sun Aug 1 0445-0900 4:05
219 Aug 7 1635-1805 Sat Aug 7 0935-1105 1:30
220 Aug 8 1120-1920 Sun Aug 8 0420-1220 8:00
Total transmit window duration: 37:50
UTC PDT AST
UTC UTC TRANSMIT WINDOW TRANSMIT WINDOW TRANSMIT WINDOW
1999 1999 START STOP START STOP START STOP
DOY Date hhmm-hhmm hhmm-hhmm hhmm-hhmm Duration
213 Aug 1 1217-1400 0517-0700 0817-1000 1:43
214 Aug 2 1135-1400 0435-0700 0735-1000 2:25
215 Aug 3 1109-1359 0409-0659 0709-0959 2:50
216 Aug 4 1100-1344 0400-0634 0700-0944 2:44
217 Aug 5 1100-1329 0400-0629 0700-0929 2:29
218 Aug 6 1215-1305 0515-0605 0815-0905 0:50
221 Aug 9 1043-1207 0343-0507 0643-0800 1:17
Total duration: 14:18
From Jon Giorgini (1999 June 27):
With 136 optical observations 10-APR-1999 to 19-JUN-1999
1-sigma X-band uncertainties for newly determined 1999 JM8
soln #2 are:
DATE Pointing X-band Dop Delay
UTC (") Hz (sec)
----------------- --------- ---------- ----------
16-JUL-1999 00:00 27.208 91.502 0.055272
19-JUL-1999 00:00 41.002 91.404 0.051009
22-JUL-1999 00:00 63.030 86.670 0.045315
25-JUL-1999 00:00 96.346 73.198 0.037030
28-JUL-1999 00:00 134.961 45.552 0.024803
31-JUL-1999 00:00 151.616 8.995 0.010299
3-AUG-1999 00:00 129.880 40.454 0.008343
6-AUG-1999 00:00 94.816 70.413 0.015429
9-AUG-1999 00:00 66.537 89.131 0.019155
There is the potential for a systematic error (bias)
not modelled in these values.
Although it is moving closer to the Sun in the POS, an
observing window will open up this week that should allow
observation while at magnitude 14+ in the morning sky
during July. Thus, additional astrometry is possible up
until around July 20, when the dark sky elevation is less
than 20 degrees. Astrometry will probably be obtainable
after that at the higher elevation angles, but will be in the
same sky as a waxing Moon (70+ deg away) over 50%+
illuminated.
- - - - - - - - - -
From Jon Giorgini (1999 June 29):
With 3 more observations reported, 139 total, solution #4 was
computed for 1999 JM8. 1-sigma X-band uncertainties with the data
arc 10-APR-1999 to 26-JUN-1999 are:
DATE Pointing X-band Dop Delay
(") Hz (sec)
----------------- --------- ---------- ----------
16-JUL-1999 00:00 18.207 77.838 0.040926
19-JUL-1999 00:00 27.677 76.775 0.037694
22-JUL-1999 00:00 42.929 71.723 0.033529
25-JUL-1999 00:00 66.233 59.305 0.027655
28-JUL-1999 00:00 93.699 35.215 0.019165
31-JUL-1999 00:00 106.388 6.613 0.009261
3-AUG-1999 00:00 92.221 36.220 0.006339
6-AUG-1999 00:00 68.218 60.385 0.010415
9-AUG-1999 00:00 48.584 75.060 0.013015
- - - - - - - - - -
From Jon Giorgini (1999 June 30):
With 7 more observations from Bill Owen at JPL's Table Mountain,
1999 JM8 solution #6 was computed and 1-sigma X-band uncertainties
found to be:
DATE Pointing X-band Dop Delay
(") Hz (sec)
----------------- --------- ---------- ----------
16-JUL-1999 00:00 9.532 65.467 0.027391
19-JUL-1999 00:00 14.847 63.606 0.025093
22-JUL-1999 00:00 23.621 58.348 0.022351
25-JUL-1999 00:00 37.299 46.972 0.018746
28-JUL-1999 00:00 54.101 26.149 0.013782
31-JUL-1999 00:00 63.046 5.549 0.008119
3-AUG-1999 00:00 56.160 31.920 0.005330
6-AUG-1999 00:00 42.756 50.883 0.006545
9-AUG-1999 00:00 31.394 61.954 0.008126
- - - - - - - - - -
From Jon Giorgini (1999 July 1):
With 151 obs 10-APR-1999 to 30-JUN-1999, 1999 JM8
solution #8 1-sigma X-band uncertainties are:
DATE Pointing X-band Dop Delay
(") Hz (sec)
----------------- --------- ---------- ----------
16-JUL-1999 00:00 6.866 62.817 0.024225
19-JUL-1999 00:00 11.070 60.780 0.022139
22-JUL-1999 00:00 18.128 55.461 0.019735
25-JUL-1999 00:00 29.349 44.273 0.016689
28-JUL-1999 00:00 43.531 24.075 0.012591
31-JUL-1999 00:00 51.773 5.318 0.007886
3-AUG-1999 00:00 46.999 31.066 0.005120
6-AUG-1999 00:00 36.421 48.936 0.005591
9-AUG-1999 00:00 27.191 59.230 0.006916
- - - - - - - - - -
From Jon Giorgini (1999 July 8):
With 175 optical observations of 1999 JM8 from 10-APR-1999
to 4-JUL-1999, solution #10 was determined and found to have
1-sigma X-band uncertainties as follows:
DATE Pointing X-band Dop Delay
(") Hz (sec)
----------------- --------- ---------- ----------
16-JUL-1999 00:00 5.147 58.697 0.020676
19-JUL-1999 00:00 8.463 56.599 0.018822
22-JUL-1999 00:00 14.087 51.459 0.016751
25-JUL-1999 00:00 23.135 40.899 0.014217
28-JUL-1999 00:00 34.758 22.068 0.010907
31-JUL-1999 00:00 41.837 5.131 0.007191
3-AUG-1999 00:00 38.414 28.837 0.005055
6-AUG-1999 00:00 30.096 45.170 0.005429
9-AUG-1999 00:00 22.708 54.500 0.006643
- - - - - - - - - -
From Jon Giorgini (1999 July 9):
Accepting the identification of 1999 JM8 as being 1990 HD1,
and incorporating recent astrometry of 1999 JM8, a new solution
#13 was developed and found to have 1-sigma X-band uncertainties
as follows (data arc 29-APR-1990 to 6-JUL-1999):
DATE Pointing X-band Dop Delay
(") Hz (sec)
----------------- --------- ---------- ----------
16-JUL-1999 00:00 2.246 1.290 0.006927
19-JUL-1999 00:00 3.916 1.450 0.006760
22-JUL-1999 00:00 6.862 1.520 0.006412
25-JUL-1999 00:00 11.800 1.436 0.005696
28-JUL-1999 00:00 18.495 1.710 0.004322
31-JUL-1999 00:00 23.161 3.009 0.002255
3-AUG-1999 00:00 22.080 4.529 0.000578
6-AUG-1999 00:00 17.931 5.623 0.001665
9-AUG-1999 00:00 14.001 6.286 0.002576
As a comment, a pass through of the data with solution #10
(fit prior to the 1990 HD1 identification) showed the four 1990
observations with residuals of -3300" RA*cos(dec) and 100 to 150"
in DEC relative to solution #10 trajectory.
Subsequent iterations were unable to fit 2 of the 1990 DEC values to
better than 3-4", so those two early observations were deleted for now.
Gareth Williams writes:
>> jdg:
>> How much confidence is there in the identification of 1990 HD1
>> as being 1999 JM8?
> Pretty certain (otherwise we wouldn't have published it :-).
>
> The somewhat poor residuals in 1990 are not unexpected for photographic
>observations, particularly those from the 18-inch Palomar Schmidt. Just
>looking at the 1990 observations alone, there are indications that the
>object is unusual.
- - - - - - - - - -
From Jon Giorgini (1999 July 12):
With new astrometry (201 observations total),
1999 JM8 solution #15 1-sigma X-band uncertainties are:
DATE Pointing X-band Dop Delay
(") Hz (sec)
----------------- --------- ---------- ----------
16-JUL-1999 00:00 2.141 1.272 0.006721
19-JUL-1999 00:00 3.750 1.420 0.006562
22-JUL-1999 00:00 6.596 1.482 0.006229
25-JUL-1999 00:00 11.376 1.409 0.005540
28-JUL-1999 00:00 17.876 1.708 0.004216
31-JUL-1999 00:00 22.434 2.986 0.002217
3-AUG-1999 00:00 21.427 4.460 0.000561
6-AUG-1999 00:00 17.429 5.513 0.001582
9-AUG-1999 00:00 13.630 6.147 0.002467
- - - - - - - - - -
From Jon Giorgini (1999 July 17):
Incorporating the observations sent directly by Lenka
Sarounova, making a total of 220 useable spanning 29-APR-1990
to 15-JUL-1999 20:36, 1999 JM8 solution #17 was determined and
found to have 1-sigma X-band uncertainties as follows:
DATE Pointing X-band Dop Delay
(") Hz (sec)
----------------- --------- ---------- ----------
16-JUL-1999 00:00 1.084 1.159 0.003683
19-JUL-1999 00:00 1.885 1.201 0.003615
22-JUL-1999 00:00 3.354 1.240 0.003463
25-JUL-1999 00:00 5.893 1.316 0.003131
28-JUL-1999 00:00 9.462 1.653 0.002467
31-JUL-1999 00:00 12.143 2.368 0.001442
3-AUG-1999 00:00 11.859 3.094 0.000539
6-AUG-1999 00:00 9.858 3.564 0.000765
9-AUG-1999 00:00 7.869 3.811 0.001206
These will be monostatic observations.
We'll use the GSSR Controller to run automatically.
During the track on DOY 220 (!), the strategy will be to get a
CW detection and then we'll devote the rest of the track to
0.25 us x 0.075 Hz imaging.
CW setup for the DOY 220 track:
TX polarization RCP
RCV polarization LCP
Frequencies: 4
Dwell: 20 seconds
Bandwidth: 1000 Hz
Sampling interval: 10000 x 0.1 usec
VMT FFT for PSD files: 4096 for 0.244-Hz resolution
Possible ranging setups:
---------------------------------------------------------------------------
127 x 64 10-usec single sample
baud 10 usec
code 127
gates 127
FFT 64
CLT 11
ncoh 2
bandwidth 394 Hz
resolution 6.15 Hz
TXOFF TBD
incoh sums 64 => 10.4 sec/record
---------------------------------------------------------------------------
127 x 64 11-usec single sample.
baud 11 usec
code 127
gates 127
PRP 1397
FFT 64
CLT 11
ncoh 2
bandwidth 357.9 Hz
resolution 5.59 Hz
TXOFF TBD
-------------------------------------------------------------------------
0.125-usec ranging
setup JX1XS001
baud 0.125 usec
code 127
gates 127
FFT 64
ncoh 1968
bandwidth 32.008 Hz
resolution 0.5001 Hz
TXOFF 6 Hz = 12 cells, => cell 44
incoh sums 4 looks=> 8 sec/record => expect records per run ~ RTT/8
CLT gate 34.8
_____________________________________________________________________
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
_______________________________________________________________________
Ray Jurgens and Carl Franck have added 3 new configurations that
provide range over-sampling. The original long baud configurations
are set up as follows:
Config. baud over range FFT coh BW Res
micro samp gates freqs sums Hz Hz
sec
JX1XS0700 7.0 1 127 64 3 375 5.86
JX1XS1000 10.0 1 127 64 2 394 6.15
JX1XS1100 11.0 1 127 64 2 358 5.59
We added the following to the JX set:
JX1XS0350 7.0 2 254 64 3 375 5.86
JX1XS0500 10.0 2 254 64 2 394 6.15
JX1XS0550 11.0 2 254 64 2 358 5.59
These new configurations have exactly the same coverage in range
and Doppler frequency as the previus set. They provide 2 range samples
per baud filling in the deep hole between gates in the original set. The
only disadvantages in using these are that they record more data in a
given amount of time for the same amount of integration, and the display
is crowded if you try to show all gates at one time.
SNR tests using the these are essentially identical to the originals.
____________________________________________________________________
RANGING SETUPS from Toutatis 1992: (code=255, FFT=256, 1 channel)
____________________________________________________________________
Setup Baud NACC bandwidth resolution 1/res'n CLT
Hz Hz sec gate
____________________________________________________________________
TU1XS01 0.125 123 255.06 0.9963 1.00 34
890 35.25 0.1377 7.26
1471 21.327 0.08331 12.00
2210 14.196 0.05545 18.03
2942 10.664 0.04166 24.01
3309 9.4810 0.03704 27.00
3700 8.4791 0.03312 30.19
7400 4.2395 0.01656 60.38
14800 2.1198 0.00828 120.77
TU1XS02 0.25 123 127.5 0.498
TU1XS04 0.500 307 25.5 0.100
TU1XS08 1.000 153 25.6 0.100
TU1XS16 2.000 4 490.2 1.915
TU1XS32 4.000 2 490.2 1.915
TU1XS33 4.125 2 475.3 1.857
TU1XS80 10.000 1 392.2 1.532 11
TU1XS88 11.000 1 356.5 1.393 11
For these observations, we need the following files:
PRDX.OUT.s26
PUNCH.OUT.s26
These files are created in: intruder:/export/data2/osod/ops/1999jm8/
and are copied to: intruder:/d1/1999JM8/support/
POINTING
Date (UTC) DOY hhmmss RA Dec MACRO TX Offsets RTT OSOD
LHA Dec
1999 08 07 219 160000 64.2117 6.3765 A 81.4 26
1999 08 07 219 170000 64.1504 6.2451 A 0.0014 -0.0030 81.6 26
1999 08 07 219 180000 64.0903 6.1142 A 81.8 26
1999 08 08 220 110000 63.2403 3.9952 A 85.5 26
1999 08 08 220 120000 63.1869 3.8766 85.7 26
1999 08 08 220 130000 63.1328 3.7584 85.9 26
1999 08 08 220 140000 63.0781 3.6407 86.1 26
1999 08 08 220 150000 63.0234 3.5236 A 0.0013 -0.0028 86.3 26
1999 08 08 220 160000 62.9691 3.4069 86.6 26
1999 08 08 220 170000 62.9155 3.2907 86.8 26
1999 08 08 220 180000 62.8630 3.1751 87.0 26
1999 08 08 220 190000 62.8120 3.0600 A 87.2 26
1999 08 08 220 200000 62.7626 2.9455 87.5 26
PRDX.OUT.s26
RECEIVER U.T. RANGE DOPPLER LHA DEC AZ EL
1999 AUG 07 16:30 81.5194970201 -505041.827 22.1840 6.3107 220.212 54.458
1999 AUG 07 16:40 81.5549343262 -506099.689 24.7010 6.2888 223.731 53.068
1999 AUG 07 16:50 81.5904451674 -507140.046 27.2181 6.2670 227.036 51.590
1999 AUG 07 17:00 81.6260282776 -508161.245 29.7350 6.2451 230.138 50.034
1999 AUG 07 17:10 81.6616822472 -509161.668 32.2520 6.2232 233.053 48.410
1999 AUG 07 17:20 81.6974055643 -510139.740 34.7689 6.2014 235.796 46.725
1999 AUG 07 17:30 81.7331966080 -511093.926 37.2858 6.1796 238.382 44.988
1999 AUG 07 17:40 81.7690536514 -512022.737 39.8026 6.1578 240.825 43.203
1999 AUG 07 17:50 81.8049748746 -512924.733 42.3194 6.1360 243.139 41.378
1999 AUG 07 18:00 81.8409583295 -513798.526 44.8362 6.1142 245.337 39.516
1999 AUG 07 18:10 81.8770020112 -514642.782 47.3529 6.0925 247.430 37.623
PRDX.OUT.s26
RECEIVER U.T. RANGE DOPPLER LHA DEC AZ EL
1999 AUG 08 11:20 85.5454839727 -498682.550 306.4157 3.9556 109.676 31.505
1999 AUG 08 11:30 85.5804639187 -499417.425 308.9314 3.9358 111.612 33.410
1999 AUG 08 11:40 85.6154965239 -500184.719 311.4472 3.9161 113.628 35.290
1999 AUG 08 11:50 85.6505840104 -500983.256 313.9630 3.8963 115.731 37.139
1999 AUG 08 12:00 85.6857285252 -501811.798 316.4788 3.8766 117.932 38.955
1999 AUG 08 12:10 85.7209321267 -502669.049 318.9946 3.8568 120.240 40.733
1999 AUG 08 12:20 85.7561967901 -503553.656 321.5105 3.8371 122.667 42.468
1999 AUG 08 12:30 85.7915243744 -504464.213 324.0263 3.8174 125.223 44.154
1999 AUG 08 12:40 85.8269166480 -505399.265 326.5422 3.7977 127.920 45.786
1999 AUG 08 12:50 85.8623752756 -506357.307 329.0581 3.7781 130.770 47.356
1999 AUG 08 13:00 85.8979018148 -507336.789 331.5740 3.7584 133.784 48.857
1999 AUG 08 13:10 85.9334977227 -508336.121 334.0900 3.7388 136.973 50.282
1999 AUG 08 13:20 85.9691643146 -509353.673 336.6059 3.7191 140.346 51.619
1999 AUG 08 13:30 86.0049028288 -510387.778 339.1219 3.6995 143.910 52.861
1999 AUG 08 13:40 86.0407143568 -511436.738 341.6378 3.6799 147.669 53.997
1999 AUG 08 13:50 86.0765998795 -512498.826 344.1538 3.6603 151.623 55.015
1999 AUG 08 14:00 86.1125602560 -513572.289 346.6698 3.6407 155.765 55.906
1999 AUG 08 14:10 86.1485962213 -514655.349 349.1857 3.6212 160.081 56.658
1999 AUG 08 14:20 86.1847083856 -515746.212 351.7017 3.6016 164.553 57.262
1999 AUG 08 14:30 86.2208972324 -516843.067 354.2177 3.5821 169.151 57.710
1999 AUG 08 14:40 86.2571631180 -517944.093 356.7336 3.5626 173.841 57.994
1999 AUG 08 14:50 86.2935062754 -519047.456 359.2496 3.5431 178.582 58.110
1999 AUG 08 15:00 86.3299267993 -520151.322 1.7655 3.5236 183.332 58.056
1999 AUG 08 15:10 86.3664246557 -521253.851 4.2815 3.5041 188.046 57.833
1999 AUG 08 15:20 86.4029996914 -522353.210 6.7974 3.4846 192.682 57.445
1999 AUG 08 15:30 86.4396516295 -523447.567 9.3133 3.4652 197.204 56.897
1999 AUG 08 15:40 86.4763800363 -524535.103 11.8292 3.4457 201.580 56.197
1999 AUG 08 15:50 86.5131843894 -525614.008 14.3451 3.4263 205.788 55.355
1999 AUG 08 16:00 86.5500640016 -526682.492 16.8610 3.4069 209.811 54.381
1999 AUG 08 16:10 86.5870180994 -527738.782 19.3768 3.3875 213.642 53.285
1999 AUG 08 16:20 86.6240457520 -528781.129 21.8926 3.3681 217.276 52.078
1999 AUG 08 16:30 86.6611459264 -529807.812 24.4084 3.3488 220.716 50.771
1999 AUG 08 16:40 86.6983174697 -530817.137 26.9242 3.3294 223.969 49.374
1999 AUG 08 16:50 86.7355591020 -531807.445 29.4399 3.3101 227.042 47.896
1999 AUG 08 17:00 86.7728694329 -532777.113 31.9556 3.2907 229.946 46.345
1999 AUG 08 17:10 86.8102469697 -533724.558 34.4713 3.2714 232.692 44.730
1999 AUG 08 17:20 86.8476900806 -534648.239 36.9869 3.2521 235.293 43.057
1999 AUG 08 17:30 86.8851970664 -535546.660 39.5026 3.2329 237.758 41.333
1999 AUG 08 17:40 86.9227660958 -536418.374 42.0181 3.2136 240.101 39.563
1999 AUG 08 17:50 86.9603952473 -537261.985 44.5337 3.1943 242.331 37.753
1999 AUG 08 18:00 86.9980825131 -538076.151 47.0492 3.1751 244.459 35.908
1999 AUG 08 18:10 87.0358257740 -538859.587 49.5646 3.1559 246.495 34.030
1999 AUG 08 18:20 87.0736228324 -539611.066 52.0800 3.1367 248.448 32.124
1999 AUG 08 18:30 87.1114714069 -540329.423 54.5954 3.1175 250.325 30.193
1999 AUG 08 18:40 87.1493691462 -541013.556 57.1107 3.0983 252.135 28.240
1999 AUG 08 18:50 87.1873136145 -541662.430 59.6260 3.0791 253.885 26.268
1999 AUG 08 19:00 87.2253022864 -542275.075 62.1413 3.0600 255.581 24.279
1999 AUG 08 19:10 87.2633326192 -542850.594 64.6564 3.0409 257.230 22.275
1999 AUG 08 19:20 87.3014019616 -543388.159 67.1716 3.0218 258.837 20.259
GOLDSTONE OBSERVATIONS LOG
199-200 (July 18-19)
-------------------
filename
kernel setup OSOD runs start-stop
----------------------------------------------------------
99199-4k, CW 15 8 211432-213931 4k & 16k FFTs
99199-16k --We switched FFTs on the fly--
99199-8k CW 15 11 014044-021542 8k FFT; 1st run bad
99199B CW 15 3 070604-071410 8k FFT
Bandwidth is about 1.5 Hz.
==========================================================
201 (July 20)
-------------------
filename
kernel setup OSOD runs start-stop
----------------------------------------------------------
99201 CW 17 2 023155-023633 FFT=4096
jm20103 10us x 6.15 Hz 17 3 025009-025802
jm20107 11us x 2.236 17 1 030858-031029
jm20108 1 us x 0.1 Hz 17 2 033703-034149 127 code x 64 fft
Bandwidth is about 2 Hz.
==========================================================
202 (July 21)
-------------------
filename
kernel setup OSOD runs start-stop
---------------------------------------------------------------
99202 CW 4k FFT 19 1 174136-174257
jm20203 1.0us x 0.1 Hz 19 +5 Hz 2 175851-180305 255 code x 256 pt FFT
jm20203 1.0us x 0.1 Hz 19 +5 Hz,+30us 14 180541-184433 255 code x 256 pt FFT
==========================================================
204 (July 23)
-------------------
filename
kernel setup OSOD runs start-stop
----------------------------------------------------------------
99204 CW 4k FFT 21 1 003648-003803 2 hops
jm20403 0.5 us x 0.075 Hz 21 +5 Hz 4 005306-010223 255 code x 256 pt FFT
jm20403 0.5 us x 0.075 Hz 21 +5 Hz,+25us 13 010410-013854 255 code x 256 pt FFT
==========================================================
205 (July 24)
-------------------
filename
kernel setup OSOD runs start-stop
----------------------------------------------------------------
99205 CW 4 k FFT 21 2 165825-170154 2 hops
jm20505 10 us x 2.46 Hz 21 +25 2 172513-172850 127 code x 64 pt FFT
jm20508 11 us x 2.24 Hz 21 +22 2 174329-174659 127 code x 64 pt FFT
jm20511 0.5 us x 0.075 Hz 21 +5Hz,+25us 49 180151-195954 255 code x 256 pt FFT
The bandwidth is about 2.2 Hz.
================================================================
208 (July 27)
-------------------
filename
kernel setup OSOD runs start-stop
-------------------------------------------------------------
99208 CW 4k FFT 21 2 013115-013422 2 hops
jm20803 0.25usx0.05Hz 21 2.5Hz,37.5us 30 014947-025407 255 code x 256 pt FFT
The bandwidth is about 3 Hz, the widest seen to date.
=============================================================
209 (July 28)
-------------------
filename
kernel setup OSOD runs start-stop
-------------------------------------------------------------
99209 CW 23 1 ~1714 incomplete run
jm20903 0.25us x 0.05Hz 23 +2.5 Hz,+25us 18 173023-180552 acsm stopped
jm20903 0.25us x 0.05Hz 23 +2.5 Hz,+25us 25 181013-190102 255 code x 256 pt FFT
Twin peaks!
=============================================================
212 (July 31)
-------------------
filename
kernel setup OSOD runs start-stop
----------------------------------------------------------
99212 CW 23 2 170111-170404
jm21203 0.125usx0.05Hz 23 +2.5Hz,-12.5us 48 172454-190134 VAX halted
jm21204 0.125usx0.05Hz 23 +2.5Hz,-12.5us 24 190739-195539
255 code x 256 pt FFT
==========================================================
213 (August 1)
-------------------
filename
kernel setup OSOD runs start-stop
----------------------------------------------------------
99213 CW 23 2 120321-120617
jm21303 0.125usx0.05Hz 23 +3Hz,+6.25us 2 122101-122405
" 0.125usx0.05Hz 23 +3Hz,+12.5us 3 122647-123152
" 0.125usx0.05Hz 23 +3Hz,+15us 45 123337-140627 VAX halt on run 46
jm21304 0.124usx0.05Hz 23 +3Hz,+15us 52 141225-155925
255 code x 256 pt FFT
==========================================================
219 (August 7)
-------------------
filename
kernel setup OSOD runs start-stop
----------------------------------------------------------
jm21903 0.25 us x 0.075 Hz 26 +3 Hz 2 171958-172405
" 0.25 us x 0.075 Hz 26 +3Hz,+25us 14 172616-180409
255 code x 256 point FFT
==========================================================
220 (August 8)
-------------------
filename
kernel setup OSOD runs start-stop
----------------------------------------------------------
jm22003 0.25 us x 0.075 Hz 26 +3Hz,+25us 50 115342-142242
jm22004 0.25 us x 0.075 Hz 26 +3Hz,+25us 53 142939-170807
jm22005 0.25 us x 0.075 Hz 26 +3Hz,+25us 6 171246-172906
jm22006 0.25 us x 0.075 Hz 26 +3Hz,+25us 36 173238-191931
255 code x 256 point FFT
==========================================================
ASTROMETRY
1999 07 18 21:30:00 P 580912.4D0 0.4 8560.D6 -14 -14 Benner, L.
Corr'n of +1.7 Hz to soln 15 based on cw echoes w/0.122 Hz res'n
1999 07 20 02:40:00 P 547278.4D0 0.3 8560.D6 -14 -14 Benner, L.
Corrn of -0.5 Hz to soln 17 w/0.24 Hz res'n using echo center
1999 07 20 03:00:00 R 92.6270694 10.0 8560.D6 -14 Benner, L.
Corrn of -3132.5 us to soln 17 w/10 & 11us bauds
1999 07 21 17:40:00 P 528308.3D0 0.4 8560.D6 -14 -14 Benner, L.
Corrn of +0.8 Hz to soln 19 using center freq w/0.244 Hz res'n.
1999 07 24 17:00:00 P 420950.7D0 0.3 8560.D6 -14 -14 Benner, L.
Corr'n of +0.5 Hz to soln 21 from center freq of cw echo w/0.24 Hz res'n
1999 07 24 19:00:00 R 69.426792 5.0 8560.D6 -14 Benner, L.
Corrn of -4 us to soln 21 w/0.5 us baud. Assume COM = TE +/- 5 us.
1999 07 27 01:30:00 P 264385.7D0 0.3 8560.D6 -14 -14 Benner, L.
Corr'n of +0.5 Hz to soln 21 from center freq of cw echo w/0.24 Hz res'n
1999 07 27 02:30:00 R 61.40113 5.0 8560.D6 -14 Benner, L.
Corr'n of -20 us to soln 21 w/0.25 us baud. Assume COM = TE +/- 5 us.
HIGH-RESOLUTION DELAY-DOPPLER IMAGES
JULY 20: NUMBER OF RUNS = 2
JULY 21: NUMBER OF RUNS = 14
This image has a logarithmic stretch
JULY 23: NUMBER OF RUNS = 13
This image has a logarithmic stretch
JULY 24: NUMBER OF RUNS = 49
This image has a logarithmic stretch
"MOVIE" FROM JULY 24. EACH PANEL SPANS ABOUT 40 MINUTES
AND IS AN INTEGRATION OF ABOUT 16 RUNS
JULY 27: NUMBER OF RUNS = 30 (34 looks)
This image has a linear stretch. The peak SNR/pixel
is about 30.
JULY 28: NUMBER OF RUNS = 43 (43 looks)
This image has a linear stretch. The peak SNR/pixel
is about 34.
This is the same image from July 28 but
with a logarithmic stretch
JULY 31: NUMBER OF LOOKS = 72
This image has a linear stretch. The peak SNR/pixel
is about 28.
AUGUST 1: NUMBER OF LOOKS = 102
This image has a linear stretch. The peak SNR/pixel
is about 27. Note the similarity between this image
and the ones obtained on July 24. It appears that
the rotation period about one of the axes is close
to 8 days. The bandwidth is about 3 Hz.
AUGUST 7: NUMBER OF LOOKS = 28
This image has a linear stretch. The peak SNR/pixel
is about 23. The bandwidth is 3 Hz and the visible
range extent is 2.4 km.
AUGUST 8:
11:54:10-14:22:51 UTC. 50 RUNS (250 LOOKS).
This image has a logarithmic stretch. The peak SNR/pixel
is about 42. The orientation of 1999 JM8 in this image
is similar to the orientation seen on July 24 and August 1.
14:30:06-17:03:16 UTC. 53 RUNS (264 LOOKS).
This image has a logarithmic stretch. The peak SNR/pixel
is about 43. Note the slight rotation relative to the
previous image.
17:32:38-19:19:31 UTC. 36 RUNS (180 LOOKS).
This image has a logarithmic stretch. The peak SNR/pixel
is about 30. Note the additional rotation relative to the
previous two images.
Arecibo images of 1999 JM8 are available at:
http://www.naic.edu/~margot/NEAS/1999JM8/
Last modified: 1999 August 10
Dr. Steven J. Ostro | PHONE: (818) 354-3173
300-233 | FAX: (818) 354-9476
Jet Propulsion Laboratory | email: ostro@echo.jpl.nasa.gov
Pasadena, CA 91109-8099
Asteroid Radar Astronomy