(152664) 1998 FW4 Goldstone Radar Observations Planning


Background


(152664) 1998 FW4 was discovered on March 20, 1998 by LINEAR - Lincoln Laboratory ETS in New Mexico.    
This asteroid is a moderately sized object (D ~ 0.4 km, plus/minus a factor of two), 
and it will be a very strong radar target in late September due to the closeness of its approach within
0.022 AU (less than 9 lunar distances). 

It has a highly eccentric orbit (e=0.72) with an aphelion at 4.32 AU. It makes moderately close approaches 
to Jupiter (within 1.2 AU) as well as close approaches to Venus (within 0.02 AU). It has a Tisserand parameter 
of 3.03, right at the threshold for a Jupiter-family comet, which raises the possibility that this object is 
an extinct comet. We will be able to achieve the highest resolution (19 m) with the Goldstone radar. 

Goldstone observations are scheuled on Sep. 26-28.
This object will also be observed at Arecibo on Sep. 30-Oct. 4. 

1998 FW4 has been classified as a "Potentially Hazardous Asteroid" by the 
Minor Planet Center.
Orbital and Physical Characteristics  
 orbit type               Apollo
 semimajor axis           2.511 AU     
 eccentricity             0.72
 inclination              3.5°       
 perihelion distance      0.700 AU     
 aphelion distance        4.323 AU     
 absolute magnitude (H)   19.5
 diameter                 0.4 km (plus/minus a factor of two)
 rotation period          unknown
 pole direction           unknown  
 lightcurve amplitude     unknown
 spectral class           unknown

Last update: 2009 Sep 27

Discovery

M.P.E.C. 1998-F18                                Issued 1998 Mar. 24, 23:29 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

                                   1998 FW4

Observations:
     J98F04W* C1998 03 20.22789 12 36 49.21 -03 50 23.7          19.3        704
     J98F04W  C1998 03 20.24800 12 36 45.61 -03 50 09.5          19.1        704
     J98F04W  C1998 03 20.26810 12 36 42.30 -03 49 55.3          19.2        704
     J98F04W  C1998 03 20.28830 12 36 38.55 -03 49 44.3          19.8        704
     J98F04W  C1998 03 22.34631 12 31 05.83 -03 28 09.6          19.0        704
     J98F04W  C1998 03 22.35602 12 31 04.36 -03 28 01.6          19.0        704
     J98F04W  C1998 03 22.37545 12 31 01.20 -03 27 50.2          19.3        704
     J98F04W  C1998 03 23.92565 12 27 08.55 -03 12 33.7                      557
     J98F04W  C1998 03 23.94316 12 27 05.88 -03 12 23.5          19.0 V      557
     J98F04W  C1998 03 23.96128 12 27 03.17 -03 12 12.0          18.8 V      046
     J98F04W  C1998 03 23.96272 12 27 03.01 -03 12 11.5                      046
     J98F04W  C1998 03 23.96413 12 27 02.73 -03 12 10.5                      046
     J98F04W  C1998 03 23.96576 12 27 02.65 -03 12 09.1                      046
     J98F04W  C1998 03 23.96703 12 27 02.23 -03 12 08.3                      046
     J98F04W  C1998 03 24.50031 12 25 44.67 -03 07 01.2                      673
     J98F04W  C1998 03 24.50456 12 25 44.03 -03 06 59.5                      673

Observer details:
046 Klet.  Observers M. Tichy, Z. Moravec.  Measurer M. Tichy.  0.57-m f/5.2
    reflector + CCD.
557 Ondrejov.  Observer P. Pravec.  0.65-m f/3.6 reflector + CCD.
673 Table Mountain Observatory, Wrightwood.  Observer M. L. Hicks.  Measurer
    D. L. Rabinowitz.  0.6-m reflector + CCD.
704 Lincoln Laboratory ETS, New Mexico.  Observers M. Blythe, F. Shelly,
    M. Bezpalko.  Measurers J. Stuart, H. Viggh.  1.0-m f/2.15 reflector + CCD.

Orbital elements:
1998 FW4
Epoch 1998 Mar. 8.0 TT = JDT 2450880.5                  Williams
M  13.05797              (2000.0)            P               Q
n   0.19199182     Peri.   74.14394     +0.21639465     -0.97629749
a   2.9758719      Node     3.36667     +0.86713232     +0.19027942
e   0.7809797      Incl.    3.97420     +0.44861442     +0.10313561
P   5.13           H   19.0           G   0.15
From 16 observations 1998 Mar. 20-24.

Ephemeris:
1998 FW4                 a,e,i = 2.98, 0.78, 4                   q = 0.6518
Date    TT    R. A. (2000) Decl.     Delta      r     Elong.  Phase     V
1998 03 18    12 43.31   -04 15.2    0.450    1.435   165.6     9.9    18.7
1998 03 23    12 29.43   -03 21.4    0.501    1.495   174.1     3.9    18.7
1998 03 28    12 18.03   -02 35.9    0.557    1.555   177.9     1.3    18.9
1998 04 02    12 08.88   -01 59.0    0.619    1.613   170.7     5.7    19.5
1998 04 07    12 01.77   -01 30.4    0.686    1.671   164.0     9.5    19.9
1998 04 12    11 56.44   -01 09.4    0.758    1.728   157.7    12.7    20.3
1998 04 17    11 52.63   -00 55.2    0.835    1.784   151.8    15.4    20.7
1998 04 22    11 50.14   -00 47.3    0.917    1.840   146.3    17.6    21.1
1998 04 27    11 48.79   -00 44.7    1.002    1.894   141.1    19.5    21.4
1998 05 02    11 48.42   -00 47.0    1.091    1.948   136.2    21.0    21.7
1998 05 07    11 48.90   -00 53.6    1.184    2.001   131.5    22.2    21.9

Gareth V. Williams           (C) Copyright 1998 MPC           M.P.E.C. 1998-F18


SNR Calculation

Target Name:    1998 FW4
HMag:           19.5
Diameter:       0.4 km  (plus/minus a factor of two)
Period:         2.2 h    

                                               #           max
Start date  UT  window      RA, dec   dist    runs   SNR  SNR/run
----------------------------------------------------------------
2009 Sep 25  23:46-10:49    328,  -7  0.043    273    140      9
2009 Sep 26  23:10-10:08    319,  -7  0.035    326    330     20
2009 Sep 27  22:16-09:08    306,  -6  0.028    392    790     44
2009 Sep 28  20:57-07:45    286,  -4  0.023    458   1600     83
2009 Sep 29  19:12-06:12    262,  -2  0.022    490   2000     96
2009 Sep 30  17:27-04:52    240,   1  0.025    463   1200     62
2009 Oct 01  16:07-03:56    224,   3  0.031    402    540     29
2009 Oct 02  15:13-03:17    213,   4  0.039    341    230     13

Goldstone SNRs assume Ptx = 430 kW 

Track Assignments


Goldstone Schedule

         UT          UT      PDT                    AST                      Duration  Round-trip
DOY     Date      TX Window  TX Window              TX Window                hh:mm     time (sec)  SNR/Run 
---     ----      ---------  ---------              ---------                --------- -------     -------
269     Sep 26    0130-0700  1830-0000  Sep 25      2130-0300 Sep 25/26      05:30       43.1         9
270     Sep 27    0315-0820  2015-0120  Sep 26/27   2315-0420 Sep 26/27      05:05       34.6        20
271     Sep 28    0315-0635  2015-2335  Sep 27      2315-0235 Sep 27/28      03:20       27.5        44

Arecibo Schedule

273     Sep 30    1921-2036  1221-1336  Sep 30      1521-1636 Sep 30         01:15       24.7       800    
274     Oct 01    1757-1937  1057-1237  Oct 01      1357-1537 Oct 01         01:40       30.1       470 
275     Oct 02    1703-1855  1003-1155  Oct 02      1303-1455 Oct 02         01:52       37.9       220 
276     Oct 03    1626-1825  0926-1125  Oct 03      1226-1425 Oct 03         01:59       46.4       110 
277     Oct 04    1600-1803  0900-1103  Oct 04      1900-2103 Oct 04         02:03       55.8        58

Arecibo SNRs assume Ptx = 500 kW


Uncertainties

From Jon Giorgini, 2009 Sep 22:
With 179 optical measurements (1994-Mar-9 to 2009-Sep-21),
solution #28 was computed. Formal 3-sigma X-band uncertainties
are shown below.

Date__(UT)__HR:MN   POS_3sigma   DOP_X_3sig  RT_delay_3sig
 2009-Sep-24 00:00        1.064         1.23       0.000998
 2009-Sep-25 00:00        1.355         1.28       0.001004
 2009-Sep-26 00:00        1.861         1.35       0.001003
 2009-Sep-27 00:00        2.831         1.41       0.000979
 2009-Sep-28 00:00        4.748         1.46       0.000898
 2009-Sep-29 00:00        7.920         1.45       0.000687

From Horizons, 2009 Sep 11: JPL Solution 20, #obs = 122 (1994-2009):
 2009-Sep-20 00:00 *m  346.47418  -7.23595 0.10470587102072       1.536        0.38        1.37       0.001171
 2009-Sep-21 00:00 *m  345.07896  -7.27510 0.09436276936111       1.698        0.40        1.41       0.001193
 2009-Sep-22 00:00 *m  343.35338  -7.31246 0.08413309552413       1.893        0.41        1.46       0.001217
 2009-Sep-23 00:00 *m  341.16735  -7.34469 0.07403783051472       2.131        0.42        1.50       0.001243
 2009-Sep-24 00:00 *m  338.31472  -7.36465 0.06411390740739       2.430        0.43        1.55       0.001271
 2009-Sep-25 00:00 *m  334.45321  -7.35622 0.05442809835493       2.822        0.45        1.60       0.001300
 2009-Sep-26 00:00 *m  328.98577  -7.28065 0.04510677939988       3.384        0.46        1.64       0.001326
 2009-Sep-27 00:00 *m  320.83060  -7.03895 0.03640398610586       4.323        0.46        1.66       0.001337
 2009-Sep-28 00:00 *m  308.07799  -6.37294 0.02885934531841       6.226        0.46        1.64       0.001296
 2009-Sep-29 00:00 *m  288.27892  -4.72619 0.02359102325808       9.897        0.43        1.52       0.001109
 2009-Sep-30 00:00 *m  262.41224  -1.75765 0.02226830578782      13.379        0.38        1.37       0.000708
 2009-Oct-01 00:00 *m  238.68866   1.29784 0.02551475070930      12.745        0.39        1.41       0.000424
 2009-Oct-02 00:00 *   222.37550   3.29489 0.03197738821073      10.058        0.44        1.56       0.000559
 2009-Oct-03 00:00 *   212.04224   4.42261 0.04014628167694       7.747        0.48        1.71       0.000742
 2009-Oct-04 00:00 *   205.31452   5.07294 0.04919621941168       6.133        0.51        1.83       0.000876
 2009-Oct-05 00:00 *   200.70251   5.46987 0.05874090740422       5.021        0.54        1.94       0.000974

From Horizons, 2009 Aug 23: JPL Solution 16, #obs = 98 (1994-2009):
 Date__(UT)__HR:MN     R.A._(a-appar)_DEC.            delta  POS_3sigma  DOP_S_3sig  DOP_X_3sig  RT_delay_3sig
 2009-Sep-20 00:00     346.59082  -7.16718 0.10469435191246       4.204        1.09        3.89       0.002907
 2009-Sep-21 00:00     345.19348  -7.20522 0.09435263592013       4.544        1.11        3.98       0.002988
 2009-Sep-22 00:00     343.46532  -7.24123 0.08412455777119       4.922        1.14        4.07       0.003078
 2009-Sep-23 00:00     341.27607  -7.27179 0.07403117949189       5.333        1.16        4.14       0.003178
 2009-Sep-24 00:00     338.41935  -7.28967 0.06410956169050       5.764        1.17        4.20       0.003290
 2009-Sep-25 00:00     334.55255  -7.27861 0.05442668495366       6.177        1.18        4.22       0.003414
 2009-Sep-26 00:00     329.07830  -7.19974 0.04510927586825       6.519        1.16        4.16       0.003545
 2009-Sep-27 00:00     320.91489  -6.95417 0.03641195056646       6.986        1.11        3.96       0.003656
 2009-Sep-28 00:00     308.15536  -6.28522 0.02887511107768       9.692        0.96        3.43       0.003654
 2009-Sep-29 00:00     288.36175  -4.64312 0.02361678157252      19.276        0.65        2.31       0.003263
 2009-Sep-30 00:00     262.52525  -1.69842 0.02230189580610      30.998        0.40        1.43       0.002153
 2009-Oct-01 00:00     238.83247   1.32340 0.02554909027132      31.866        0.76        2.71       0.000798
 2009-Oct-02 00:00     222.53060   3.29598 0.03200841378106      25.851        1.08        3.86       0.000681
 2009-Oct-03 00:00     212.19793   4.40904 0.04017357488605      20.030        1.27        4.55       0.001295
 2009-Oct-04 00:00     205.46768   5.05040 0.04922034615698      15.795        1.40        4.99       0.001743
 2009-Oct-05 00:00     200.85268   5.44144 0.05876245598265      12.820        1.48        5.31       0.002064

---------------------------------------------------------

Apparent Magnitudes and Solar Elongations:

Date__(UT)__HR:MN     R.A._(a-appar)_DEC.   APmag            delta    S-O-T /r
 2009-Sep-10 00:00     352.94019  -6.83714  16.91 0.21325265830963  175.1464 /L
 2009-Sep-11 00:00     352.61614  -6.86339  16.73 0.20198091004656  176.0207 /L
 2009-Sep-12 00:00     352.25137  -6.89124  16.56 0.19080478853126  176.6471 /L
 2009-Sep-13 00:00     351.83953  -6.92069  16.40 0.17972255909600  176.8244 /L
 2009-Sep-14 00:00     351.37273  -6.95175  16.27 0.16873265361750  176.4297 /T
 2009-Sep-15 00:00     350.84101  -6.98437  16.15 0.15783374010945  175.5584 /T
 2009-Sep-16 00:00     350.23164  -7.01852  16.03 0.14702482839886  174.3717 /T
 2009-Sep-17 00:00     349.52807  -7.05409  15.91 0.13630543821681  172.9663 /T
 2009-Sep-18 00:00     348.70840  -7.09095  15.78 0.12567587343621  171.3790 /T
 2009-Sep-19 00:00     347.74299  -7.12880  15.64 0.11513767279647  169.6108 /T
 2009-Sep-20 00:00     346.59082  -7.16718  15.49 0.10469435191246  167.6380 /T
 2009-Sep-21 00:00     345.19348  -7.20522  15.32 0.09435263592013  165.4132 /T
 2009-Sep-22 00:00     343.46532  -7.24123  15.13 0.08412455777119  162.8587 /T
 2009-Sep-23 00:00     341.27607  -7.27179  14.93 0.07403117949189  159.8512 /T
 2009-Sep-24 00:00     338.41935  -7.28967  14.71 0.06410956169050  156.1913 /T
 2009-Sep-25 00:00     334.55255  -7.27861  14.47 0.05442668495366  151.5443 /T
 2009-Sep-26 00:00     329.07830  -7.19974  14.22 0.04510927586825  145.3232 /T
 2009-Sep-27 00:00     320.91489  -6.95417  13.98 0.03641195056646  136.4577 /T
 2009-Sep-28 00:00     308.15536  -6.28522  13.83 0.02887511107768  123.0454 /T
 2009-Sep-29 00:00     288.36175  -4.64312  14.01 0.02361678157252  102.6096 /T
 2009-Sep-30 00:00     262.52525  -1.69842  14.97 0.02230189580610   76.0601 /T
 2009-Oct-01 00:00     238.83247   1.32340   n.a. 0.02554909027132   51.6992 /T
 2009-Oct-02 00:00     222.53060   3.29598   n.a. 0.03200841378106   34.9731 /T
 2009-Oct-03 00:00     212.19793   4.40904   n.a. 0.04017357488605   24.5204 /T
 2009-Oct-04 00:00     205.46768   5.05040   n.a. 0.04922034615698   18.0454 /T


Setups



CW setup:
---------------------------------------------------------------------------
TX polarization           RCP
RCV polarization          LCP & RCP
Frequency hops:           2                          
Dwell                     10 seconds                      
Bandwidth:                4000 Hz 
Sampling interval:        2500 x 0.1 usec
VME FFT for PSD files:    4096 for 0.98-Hz resolution 

Ranging setups:
---------------------------------------------------------------------------
127 x 64 10-usec single sample
baud             10 usec
code            127
gates           127
PRP            1270 usec
FFT              64   
CLT       VME     ?
          PFS     ?
ncoh              4
bandwidth        196.9 Hz   
resolution       3.1 Hz
TXOFF          +50 Hz -> echo will be centered at +16 bins or in bin 32 + 16 = 48
---------------------------------------------------------------------------
127 x 64 11-usec single sample
baud             11 usec
code            127
gates           127
PRP            1397 usec
FFT              64  
CLT       VME     ?
          PFS     ?
ncoh              4
bandwidth        179.0  Hz   
resolution       2.8  Hz
TXOFF          +50 Hz --> echo will be centered at +18 bins or in bin 32 + 18 = 50
-------------------------------------------------------------------------
1-usec single sample
baud              1 usec
code              127
ncoh              20
bandwidth         393.7  Hz
FFT               128
dfreq             3.1  Hz
TXoff            +50 Hz  (echo in bin 64+16 =80)
-------------------------------------------------------------------------------
0.25-usec imaging  
baud            0.25 usec
code            127
FFT             128
ncoh            246
bandwidth       128 Hz    
resolution      1.00 Hz
TXOFF          +20  Hz, echo is in bin 64+20=84 
--------------------------------------------------------------------------
0.125-usec 
baud           0.125 usec
code           255  
FFT            256 
ncoh           122
bandwidth      257.15 Hz      
resolution     1.0045 Hz
TXOFF          +30 Hz to put echo at 128 + 30 = bin 158 

_____________________________________________________________________
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 
____________________________________________________________________


Instructions

NOTE: Data should be moved to the appropriate subdirectories in aardvark:/export/data0/1998FW4/raw/

1998 FW4 POINTING:

  OSOD and predicts are on aardvark:

/export/data3/osod/ops/a152664/PRDX.OUT.s38
                              /PUNCH.OUT.s38
                              /EPH.OUT.s38


POINTING  
                                                          TX Offsets    
Date (UTC)   DOY  hhmmss    RA        Dec         Macro   LHA     Dec    RTT    OSOD
2009 09 28   271  030000    306.1214 -6.2052        A                    28.0  
2009 09 28   271  040000    305.3932 -6.1563        A                    27.7  
2009 09 28   271  050000    304.6519 -6.1050        A     5.70    0.40   27.5   s38   
2009 09 28   271  060000    303.8987 -6.0511        A                    27.2  
2009 09 28   271  070000    303.1350 -5.9947        A                    27.0  

Transmit offsets are given in millidegrees.  


PRDX.OUT.s38 TRANSMITTER: STATION #14, RECEIVER: STATION #14 RECEIVER U.T. RANGE DOPPLER LHA DEC RA EL 2009 SEP 28 03:00 27.9720679338 633196.985 349.0181 -6.2052 306.121 47.105 2009 SEP 28 03:10 27.9277785912 630522.923 351.6453 -6.1972 306.001 47.641 2009 SEP 28 03:20 27.8836772247 627833.661 354.2729 -6.1892 305.880 48.037 2009 SEP 28 03:30 27.8397648347 625131.325 356.9010 -6.1811 305.759 48.291 2009 SEP 28 03:40 27.7960422436 622418.054 359.5294 -6.1729 305.637 48.399 2009 SEP 28 03:50 27.7525101615 619695.996 2.1582 -6.1646 305.516 48.360 2009 SEP 28 04:00 27.7091691291 616967.303 4.7873 -6.1563 305.393 48.174 2009 SEP 28 04:10 27.6660195262 614234.128 7.4168 -6.1479 305.271 47.844 2009 SEP 28 04:20 27.6230615916 611498.618 10.0467 -6.1395 305.148 47.373 2009 SEP 28 04:30 27.5802954237 608762.910 12.6770 -6.1310 305.024 46.765 2009 SEP 28 04:40 27.5377209522 606029.128 15.3075 -6.1224 304.900 46.026 2009 SEP 28 04:50 27.4953379683 603299.377 17.9385 -6.1137 304.776 45.163 2009 SEP 28 05:00 27.4531461260 600575.737 20.5697 -6.1050 304.652 44.182 2009 SEP 28 05:10 27.4111449152 597860.263 23.2013 -6.0962 304.527 43.092 2009 SEP 28 05:20 27.3693337021 595154.976 25.8332 -6.0873 304.402 41.900 2009 SEP 28 05:30 27.3277116840 592461.860 28.4654 -6.0783 304.277 40.613 2009 SEP 28 05:40 27.2862779681 589782.859 31.0980 -6.0693 304.151 39.239 2009 SEP 28 05:50 27.2450314697 587119.871 33.7308 -6.0602 304.025 37.785 2009 SEP 28 06:00 27.2039710207 584474.744 36.3639 -6.0511 303.899 36.258 2009 SEP 28 06:10 27.1630952966 581849.274 38.9974 -6.0419 303.772 34.664 2009 SEP 28 06:20 27.1224028581 579245.200 41.6311 -6.0326 303.645 33.009 2009 SEP 28 06:30 27.0818921565 576664.196 44.2651 -6.0232 303.518 31.298 2009 SEP 28 06:40 27.0415615082 574107.876 46.8994 -6.0138 303.391 29.537 2009 SEP 28 06:50 27.0014091288 571577.782 49.5339 -6.0043 303.263 27.730 2009 SEP 28 07:00 26.9614331282 569075.387 52.1687 -5.9947 303.135 25.882

1998 FW4 GOLDSTONE MASTERLOG

============================================================================== Receive TX Setup hops dwell code ncoh FFT runs start -stop OSOD offset Poln Notes ------------------------------------------------------------------------------ POINTING TX Offsets Date (UTC) DOY hhmmss RA Dec Macro LHA Dec RTT OSOD
Dr. Lance A. M. Benner | PHONE: (818) 354-7412 Mail Stop 300-233 | FAX: (818) 354-9476 Jet Propulsion Laboratory | email: lance.benner@jpl.nasa.gov California Institute of Technology | Plan: To live long and prosper Pasadena, CA 91109-8099 http://echo.jpl.nasa.gov/asteroids/1998FW4/1998FW4_planning.html

Asteroid Radar Astronomy