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Upcoming transient event

Near Earth Orbit Asteroid Close Approach of 1998 OR2
Joe Cali

In late April and early May, an asteroid, designated 1998 OR2 will pass moderately close to Earth. Perigee distance is about 6 million km or 15 x Earth-Moon distance. At closest approach, 22:00 EST on April 29, the asteroid will move through the constellation of Hydra at about 1o every three hours against background stars, this is approximately 2/3 the rate that the Moon moves against background stars. The object travels 80o over a 2 week period centred on perigee.

The magnitude at closest approach is 10.8. This is not an event for the casual observer, more of an expert level or at least for an intermediate level user with a small to medium size scope. Magnitude 10.8 is near the visual magnitude limit for a pair of 7x50mm binoculars. Magnitude 11 is moderately easy in an 80mm refractor. Easier in anything over 100mm aperture. These objects are so small that they look like a star so the easiest way to visually identify and observe these objects is by observing the motion as it passes close to a nearby star field of similar brightness stars.  On April 29, at the very sociable hours of 8:30-10:00pm, 1998 OR2 passes through a field of similarly bright stars. During this observing window, the asteroid passes within 50”of a magnitude 10.7 star at 21:15 EST. In my opinion, this is the prime time to observe the motion of this object [Figure 2].


The 80o path of the asteroid between April 23rd and May 7th.



Animation of the orbital path of 1998 OR2 from April 21st and May 7th.



Detailed star chart for the evening of April 29th, the night of perigee.


DETAILED EPHEMERIDES

Minor Planet Ephemeris Service


Orbital Elements
This file kindly prepared by the IAU Minor Planet Center & Central Bureau for Astronomical Telegrams.
Enter these Besselian Elements into your app as a new obiting body to get it to show up on the planetarium view.
Ob Num Name
Mag.
a
e
i
Node
w
L
Epoch
52768 1998 OR2 15.8 2.384436 0.573084 5.8659 27.0154 174.5662 12.1014 2459000.5


Detailed Ephemerides APRIL 22 - MAY 8

NASA HORIZONS Web-Interface
This tool provides a web-based limited interface to JPL's HORIZONS system which can be used to generate ephemerides for solar-system bodies. Full access to HORIZONS features is available via the primary telnet interface. HORIZONS system news shows recent changes and improvements. A web-interface tutorial is available to assist new users.

Current Settings
Ephemeris Type
Target Body
Observer Location
Time Span
Table Settings
Display/Output

OBSERVER
52768 (1998 OR2)
Mount Stromlo [414] ( 14900'27.7''E, 3519'13.8''S, 741.0 m )
Start=2020-04-22, Stop=2020-05-08, Step=6 h
defaults
default (formatted HTML)


Object Data Page
JPL/HORIZONS                  52768 (1998 OR2)             2020-Mar-22 06:14:00
Rec #:   52768 (+COV) Soln.date: 2020-Mar-21_06:55:19   # obs: 2091 (1987-2020)
 
IAU76/J2000 helio. ecliptic osc. elements (au, days, deg., period=Julian yrs):
 
  EPOCH=  2457807.5 ! 2017-Feb-23.00 (TDB)         Residual RMS= .19657
   EC= .5728052280975267   QR= 1.016473389171861   TP= 2457613.8454594337
   OM= 27.06302722989552   W=  174.4320178657206   IN= 5.879761121461315
   A= 2.379414393685317    MA= 52.00278843412976   ADIST= 3.742355398198773
   PER= 3.6704             N= .268533786           ANGMOM= .021750384
   DAN= 3.71883            DDN= 1.01822            L= 201.5241552
   B= .5695021             MOID= .013769           TP= 2016-Aug-13.3454594337
 
Asteroid physical parameters (km, seconds, rotational period in hours):
   GM= n.a.                RAD= n.a.               ROTPER= 4.112
   H= 15.8                 G= .150                 B-V= n.a.
                           ALBEDO= n.a.            STYP= n.a.
 
ASTEROID comments:
1: soln ref.= JPL#237, PHA  OCC=0
2: source=ORB

Results
*******************************************************************************
Ephemeris / WWW_USER Sun Mar 22 06:14:00 2020 Pasadena, USA      / Horizons   
*******************************************************************************
Target body name: 52768 (1998 OR2)                {source: JPL#237}
Center body name: Earth (399)                     {source: DE431}
Center-site name: Mount Stromlo
*******************************************************************************
Start time      : A.D. 2020-Apr-22 00:00:00.0000 UT     
Stop  time      : A.D. 2020-May-08 00:00:00.0000 UT     
Step-size       : 360 minutes
*******************************************************************************
Target pole/equ : No model available
Target radii    : (unavailable)                                               
Center geodetic : 149.007700,-35.320485,0.7379299 {E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: 149.007700,5210.55368,-3667.362 {E-lon(deg),Dxy(km),Dz(km)}
Center pole/equ : High-precision EOP model        {East-longitude positive}
Center radii    : 6378.1 x 6378.1 x 6356.8 km     {Equator, meridian, pole}   
Target primary  : Sun
Vis. interferer : MOON (R_eq= 1737.400) km        {source: DE431}
Rel. light bend : Sun, EARTH                      {source: DE431}
Rel. lght bnd GM: 1.3271E+11, 3.9860E+05 km^3/s^2                             
Small-body perts: Yes                             {source: SB431-N16}
Atmos refraction: NO (AIRLESS)
RA format       : HMS
Time format     : CAL
EOP file        : eop.200320.p200611                                          
EOP coverage    : DATA-BASED 1962-JAN-20 TO 2020-MAR-20. PREDICTS-> 2020-JUN-10
Units conversion: 1 au= 149597870.700 km, c= 299792.458 km/s, 1 day= 86400.0 s
Table cut-offs 1: Elevation (-90.0deg=NO ),Airmass (>38.000=NO), Daylight (NO )
Table cut-offs 2: Solar elongation (  0.0,180.0=NO ),Local Hour Angle( 0.0=NO )
Table cut-offs 3: RA/DEC angular rate (     0.0=NO )                          
*******************************************************************************
Initial IAU76/J2000 heliocentric ecliptic osculating elements (au, days, deg.):
  EPOCH=  2457807.5 ! 2017-Feb-23.00 (TDB)         Residual RMS= .19657       
   EC= .5728052280975267   QR= 1.016473389171861   TP= 2457613.8454594337     
   OM= 27.06302722989552   W=  174.4320178657206   IN= 5.879761121461315      
  Equivalent ICRF heliocentric equatorial cartesian coordinates (au, au/d):
   X= 1.769599056990521E+00  Y=-1.181712637227931E+00  Z=-7.405197041526462E-01
  VX= 1.123399293640273E-02 VY= 3.269663458858851E-03 VZ= 1.191080589202955E-03
Asteroid physical parameters (km, seconds, rotational period in hours):       
   GM= n.a.                RAD= n.a.               ROTPER= 4.112              
   H= 15.8                 G= .150                 B-V= n.a.                  
                           ALBEDO= n.a.            STYP= n.a.                 
*******************************************************************************************************
 Date__(UT)__HR:MN     R.A._____(ICRF)_____DEC  APmag            delta      deldot    S-O-T /r    S-T-O
*******************************************************************************************************
$$SOE
 2020-Apr-22 00:00 *m  09 13 02.19 +12 11 59.4  12.11 0.05596696692739  -5.8606921 104.8760 /T  72.0857
 2020-Apr-22 06:00 *m  09 15 09.16 +11 23 45.3  12.06 0.05511500034443  -5.7966055 105.3582 /T  71.6574
 2020-Apr-22 12:00     09 17 05.78 +10 33 25.2  12.02 0.05432256544367  -5.1661400 105.8074 /T  71.2584
 2020-Apr-22 18:00     09 19 17.09 +09 40 58.7  11.97 0.05359820434423  -5.0077326 106.3226 /T  70.7907
 2020-Apr-23 00:00 *m  09 21 45.67 +08 47 29.3  11.93 0.05284679519232  -5.4115495 106.9148 /T  70.2484
 2020-Apr-23 06:00 *m  09 24 06.19 +07 52 52.7  11.88 0.05206036151070  -5.3369973 107.4833 /T  69.7316
 2020-Apr-23 12:00     09 26 15.87 +06 56 11.4  11.83 0.05133594647152  -4.6804735 108.0151 /T  69.2476
 2020-Apr-23 18:00     09 28 40.83 +05 57 28.1  11.79 0.05068431383157  -4.4867769 108.6142 /T  68.6934
 2020-Apr-24 00:00 *m  09 31 24.41 +04 57 26.3  11.74 0.05000991061423  -4.8692001 109.2964 /T  68.0587
 2020-Apr-24 06:00 *m  09 34 00.17 +03 55 59.4  11.69 0.04930259024512  -4.7831168 109.9550 /T  67.4490
 2020-Apr-24 12:00     09 36 24.51 +02 52 34.9  11.64 0.04865981044539  -4.1000442 110.5715 /T  66.8775
 2020-Apr-24 18:00     09 39 04.69 +01 47 21.1  11.60 0.04809487605238  -3.8664222 111.2549 /T  66.2361
 2020-Apr-25 00:00 *m  09 42 04.96 +00 40 36.4  11.55 0.04751225485295  -4.2221169 112.0262 /T  65.5093
 2020-Apr-25 06:00 *m  09 44 57.77 -00 27 49.6  11.50 0.04689925754041  -4.1242158 112.7731 /T  64.8080
 2020-Apr-25 12:00     09 47 38.49 -01 37 57.7  11.46 0.04635313742115  -3.4161382 113.4703 /T  64.1525
 2020-Apr-25 18:00     09 50 35.52 -02 49 30.7  11.42 0.04589001626238  -3.1392702 114.2311 /T  63.4301
 2020-Apr-26 00:00 *m  09 53 54.23 -04 02 40.7  11.37 0.04541499435025  -3.4632717 115.0827 /T  62.6193
 2020-Apr-26 06:00 *m  09 57 05.93 -05 17 43.7  11.32 0.04491245801274  -3.3547992 115.9074 /T  61.8365
 2020-Apr-26 12:00     10 00 04.78 -06 34 02.2  11.28 0.04447859897623  -2.6263563 116.6720 /T  61.1095
 2020-Apr-26 18:00     10 03 20.26 -07 51 06.7  11.24 0.04413255412445  -2.3054023 117.4936 /T  60.3221
 2020-Apr-27 00:00 *   10 06 59.08 -09 09 44.2  11.20 0.04378083560488  -2.5941025 118.4061 /T  59.4461
 2020-Apr-27 06:00 *m  10 10 31.49 -10 30 19.2  11.16 0.04340454324532  -2.4786632 119.2868 /T  58.6028
 2020-Apr-27 12:00     10 13 50.11 -11 51 31.3  11.12 0.04309771898962  -1.7384941 120.0944 /T  57.8280
 2020-Apr-27 18:00     10 17 25.46 -13 12 34.4  11.09 0.04288261069523  -1.3762070 120.9492 /T  57.0026
 2020-Apr-28 00:00 *   10 21 25.84 -14 34 54.2  11.05 0.04266807503346  -1.6283851 121.8913 /T  56.0920
 2020-Apr-28 06:00 *m  10 25 20.50 -15 59 07.3  11.01 0.04243162885755  -1.5124542 122.7942 /T  55.2211
 2020-Apr-28 12:00     10 29 00.28 -17 23 08.7  10.98 0.04226391662031  -0.7733826 123.6096 /T  54.4330
 2020-Apr-28 18:00     10 32 56.54 -18 45 53.0  10.96 0.04219028920081  -0.3766098 124.4599 /T  53.6066
 2020-Apr-29 00:00 *   10 37 19.45 -20 09 25.1  10.93 0.04212298869942  -0.5940238 125.3905 /T  52.7017
 2020-Apr-29 06:00 *m  10 41 37.42 -21 34 38.4  10.90 0.04203577723060  -0.4866495 126.2731 /T  51.8452
 2020-Apr-29 12:00  m  10 45 39.19 -22 58 46.7  10.88 0.04201463660209   0.2353963 127.0543 /T  51.0851
 2020-Apr-29 18:00     10 49 56.75 -24 20 22.9  10.86 0.04208793374711   0.6563596 127.8577 /T  50.2993
 2020-Apr-30 00:00 *   10 54 42.39 -25 42 09.3  10.84 0.04217236353436   0.4692763 128.7326 /T  49.4438
 2020-Apr-30 06:00 *m  10 59 23.90 -27 05 20.8  10.83 0.04223793790846   0.5578336 129.5504 /T  48.6454
 2020-Apr-30 12:00  m  11 03 47.64 -28 26 37.3  10.81 0.04236487289303   1.2462069 130.2563 /T  47.9537
 2020-Apr-30 18:00     11 08 25.90 -29 44 09.9  10.81 0.04258442075806   1.6794556 130.9743 /T  47.2467
 2020-May-01 00:00 *   11 13 33.32 -31 01 12.4  10.80 0.04281870826379   1.5168100 131.7545 /T  46.4790
 2020-May-01 06:00 *m  11 18 37.41 -32 19 24.6  10.79 0.04303419320172   1.5771324 132.4705 /T  45.7752
 2020-May-01 12:00  m  11 23 21.89 -33 35 03.8  10.79 0.04330453692433   2.2173973 133.0701 /T  45.1827
 2020-May-01 18:00     11 28 18.95 -34 46 00.1  10.79 0.04366372479530   2.6517617 133.6761 /T  44.5808
 2020-May-02 00:00 *   11 33 45.74 -35 55 49.2  10.79 0.04404008255814   2.5077643 134.3364 /T  43.9260
 2020-May-02 06:00 *m  11 39 09.92 -37 06 37.9  10.80 0.04439686505436   2.5331319 134.9288 /T  43.3385
 2020-May-02 12:00  m  11 44 12.44 -38 14 33.1  10.80 0.04480077448369   3.1153401 135.4071 /T  42.8603
 2020-May-02 18:00     11 49 24.87 -39 17 04.9  10.82 0.04528835656664   3.5422338 135.8910 /T  42.3736
 2020-May-03 00:00 *   11 55 06.98 -40 18 00.4  10.83 0.04579459834211   3.4123608 136.4237 /T  41.8396
 2020-May-03 06:00 *m  12 00 47.06 -41 19 52.2  10.84 0.04627998591841   3.3996269 136.8884 /T  41.3727
 2020-May-03 12:00  m  12 06 03.31 -42 18 48.5  10.85 0.04680422174485   3.9191412 137.2471 /T  41.0074
 2020-May-03 18:00     12 11 26.18 -43 12 01.2  10.87 0.04740621158503   4.3333004 137.6151 /T  40.6305
 2020-May-04 00:00 *   12 17 17.96 -44 03 17.9  10.89 0.04802773231794   4.2146788 138.0280 /T  40.2098
 2020-May-04 06:00 *m  12 23 08.20 -44 55 34.2  10.91 0.04862694393934   4.1640224 138.3759 /T  39.8533
 2020-May-04 12:00  m  12 28 32.48 -45 45 08.3  10.93 0.04925679388076   4.6209410 138.6296 /T  39.5870
 2020-May-04 18:00     12 33 59.62 -46 28 56.8  10.95 0.04995832122687   5.0201375 138.8985 /T  39.3035
 2020-May-05 00:00 *   12 39 54.29 -47 10 38.4  10.98 0.05067992447363   4.9112949 139.2100 /T  38.9788
 2020-May-05 06:00 *   12 45 47.82 -47 53 27.0  11.00 0.05137783680419   4.8252789 139.4607 /T  38.7139
 2020-May-05 12:00  m  12 51 13.54 -48 33 57.6  11.03 0.05209868563770   5.2230940 139.6307 /T  38.5261
 2020-May-05 18:00  m  12 56 38.18 -49 08 54.5  11.06 0.05288540340220   5.6073135 139.8224 /T  38.3153
 2020-May-06 00:00 *   13 02 28.51 -49 41 40.5  11.08 0.05369262274377   5.5076650 140.0546 /T  38.0652
 2020-May-06 06:00 *   13 08 18.10 -50 15 43.0  11.11 0.05447498267747   5.3901505 140.2309 /T  37.8699
 2020-May-06 12:00  m  13 13 38.51 -50 47 57.4  11.14 0.05527333154484   5.7343090 140.3394 /T  37.7395
 2020-May-06 18:00  m  13 18 54.10 -51 14 58.9  11.17 0.05613226003577   6.1048644 140.4756 /T  37.5806
 2020-May-07 00:00 *   13 24 33.26 -51 39 50.7  11.20 0.05701211434445   6.0142333 140.6501 /T  37.3844
 2020-May-07 06:00 *   13 30 12.16 -52 06 08.4  11.23 0.05786620271247   5.8695034 140.7734 /T  37.2385
 2020-May-07 12:00  m  13 35 21.15 -52 31 09.0  11.26 0.05873017779474   6.1662530 140.8404 /T  37.1463
 2020-May-07 18:00  m  13 40 22.05 -52 51 22.7  11.30 0.05965007356966   6.5250845 140.9396 /T  37.0216
 2020-May-08 00:00 *   13 45 44.35 -53 09 31.0  11.33 0.06059136912104   6.4433791 141.0749 /T  36.8618
$$EOE
*******************************************************************************************************




*******************************************************************************************************


SIX HOURLY EPHEMERIS APRIL 9 - MAY 8
Object Data Page
JPL/HORIZONS                  52768 (1998 OR2)             2020-Apr-09 00:34:58
Rec #:   52768 (+COV) Soln.date: 2020-Apr-08_06:21:13   # obs: 2933 (1987-2020)
 
IAU76/J2000 helio. ecliptic osc. elements (au, days, deg., period=Julian yrs):
 
  EPOCH=  2457895.5 ! 2017-May-22.00 (TDB)         Residual RMS= .20083
   EC= .572793283722937    QR= 1.016595413114546   TP= 2457613.8483493342
   OM= 27.06327209776162   W=  174.4399336720654   IN= 5.879736774088401
   A= 2.379633499149479    MA= 75.62254058443961   ADIST= 3.742671585184413
   PER= 3.67091            N= .268496699           ANGMOM= .021751606
   DAN= 3.71921            DDN= 1.01834            L= 201.5322748
   B= .5686926             MOID= .0143959          TP= 2016-Aug-13.3483493342
 
Asteroid physical parameters (km, seconds, rotational period in hours):
   GM= n.a.                RAD= n.a.               ROTPER= 4.112
   H= 15.8                 G= .150                 B-V= n.a.
                           ALBEDO= n.a.            STYP= n.a.
 
ASTEROID comments:
1: soln ref.= JPL#255, PHA  OCC=0
2: source=ORB
Results
*******************************************************************************
Ephemeris / WWW_USER Thu Apr  9 00:34:58 2020 Pasadena, USA      / Horizons   
*******************************************************************************
Target body name: 52768 (1998 OR2)                {source: JPL#255}
Center body name: Earth (399)                     {source: DE431}
Center-site name: Mount Stromlo
*******************************************************************************
Start time      : A.D. 2020-Apr-09 00:00:00.0000 UT     
Stop  time      : A.D. 2020-May-08 00:00:00.0000 UT     
Step-size       : 360 minutes
*******************************************************************************
Target pole/equ : No model available
Target radii    : (unavailable)                                               
Center geodetic : 149.007700,-35.320485,0.7379299 {E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: 149.007700,5210.55368,-3667.362 {E-lon(deg),Dxy(km),Dz(km)}
Center pole/equ : High-precision EOP model        {East-longitude positive}
Center radii    : 6378.1 x 6378.1 x 6356.8 km     {Equator, meridian, pole}   
Target primary  : Sun
Vis. interferer : MOON (R_eq= 1737.400) km        {source: DE431}
Rel. light bend : Sun, EARTH                      {source: DE431}
Rel. lght bnd GM: 1.3271E+11, 3.9860E+05 km^3/s^2                             
Small-body perts: Yes                             {source: SB431-N16}
Atmos refraction: NO (AIRLESS)
RA format       : HMS
Time format     : CAL
EOP file        : eop.200408.p200630                                          
EOP coverage    : DATA-BASED 1962-JAN-20 TO 2020-APR-08. PREDICTS-> 2020-JUN-29
Units conversion: 1 au= 149597870.700 km, c= 299792.458 km/s, 1 day= 86400.0 s
Table cut-offs 1: Elevation (-90.0deg=NO ),Airmass (>38.000=NO), Daylight (NO )
Table cut-offs 2: Solar elongation (  0.0,180.0=NO ),Local Hour Angle( 0.0=NO )
Table cut-offs 3: RA/DEC angular rate (     0.0=NO )                          
*******************************************************************************
Initial IAU76/J2000 heliocentric ecliptic osculating elements (au, days, deg.):
  EPOCH=  2457895.5 ! 2017-May-22.00 (TDB)         Residual RMS= .20083       
   EC= .572793283722937    QR= 1.016595413114546   TP= 2457613.8483493342     
   OM= 27.06327209776162   W=  174.4399336720654   IN= 5.879736774088401      
  Equivalent ICRF heliocentric equatorial cartesian coordinates (au, au/d):
   X= 2.594513395297817E+00  Y=-8.071786125754339E-01  Z=-5.795173721973448E-01
  VX= 7.661860472515089E-03 VY= 4.963525131290760E-03 VZ= 2.307608855850730E-03
Asteroid physical parameters (km, seconds, rotational period in hours):       
   GM= n.a.                RAD= n.a.               ROTPER= 4.112              
   H= 15.8                 G= .150                 B-V= n.a.                  
                           ALBEDO= n.a.            STYP= n.a.                 
*******************************************************************************************************
 Date__(UT)__HR:MN     R.A._____(ICRF)_____DEC  APmag            delta      deldot    S-O-T /r    S-T-O
*******************************************************************************************************
$$SOE
 2020-Apr-09 00:00 *   08 09 28.22 +33 38 56.6  13.67 0.10774876135889  -7.6054734  97.7065 /T  76.2923
 2020-Apr-09 06:00 *   08 10 10.05 +33 27 55.3  13.65 0.10664116878519  -7.6122190  97.6565 /T  76.4019
 2020-Apr-09 12:00  m  08 10 44.88 +33 15 46.6  13.64 0.10557430965761  -7.1613160  97.5851 /T  76.5305
 2020-Apr-09 18:00  m  08 11 28.02 +33 02 28.0  13.62 0.10454979357886  -7.1510279  97.5447 /T  76.6262
 2020-Apr-10 00:00 *   08 12 19.87 +32 49 44.9  13.60 0.10348503517352  -7.5978425  97.5343 /T  76.6946
 2020-Apr-10 06:00 *   08 13 04.90 +32 37 38.4  13.58 0.10237878631013  -7.6001052  97.5008 /T  76.7882
 2020-Apr-10 12:00  m  08 13 42.78 +32 24 21.2  13.56 0.10131420474006  -7.1423639  97.4455 /T  76.9013
 2020-Apr-10 18:00  m  08 14 29.33 +32 09 51.2  13.54 0.10029257486831  -7.1311401  97.4229 /T  76.9796
 2020-Apr-11 00:00 *   08 15 24.88 +31 55 55.6  13.52 0.09923054236119  -7.5795218  97.4317 /T  77.0292
 2020-Apr-11 06:00 *   08 16 13.43 +31 42 34.8  13.49 0.09812717002375  -7.5773801  97.4167 /T  77.1047
 2020-Apr-11 12:00  m  08 16 54.66 +31 27 59.8  13.47 0.09706643477319  -7.1121758  97.3795 /T  77.2000
 2020-Apr-11 18:00  m  08 17 44.93 +31 12 08.8  13.45 0.09604937721366  -7.0992071  97.3769 /T  77.2586
 2020-Apr-12 00:00 *m  08 18 44.53 +30 56 50.5  13.43 0.09499182636759  -7.5490519  97.4074 /T  77.2868
 2020-Apr-12 06:00 *   08 19 36.93 +30 42 05.0  13.40 0.09389307462536  -7.5425704  97.4134 /T  77.3416
 2020-Apr-12 12:00  m  08 20 21.85 +30 26 01.4  13.38 0.09283797292206  -7.0691833  97.3968 /T  77.4165
 2020-Apr-12 18:00  m  08 21 16.20 +30 08 38.2  13.36 0.09182741044713  -7.0535237  97.4168 /T  77.4527
 2020-Apr-13 00:00 *m  08 22 20.25 +29 51 45.5  13.33 0.09077634909361  -7.5046620  97.4718 /T  77.4565
 2020-Apr-13 06:00 *   08 23 16.91 +29 35 22.9  13.31 0.08968421956692  -7.4938740  97.5017 /T  77.4876
 2020-Apr-13 12:00  m  08 24 05.92 +29 17 38.0  13.28 0.08863680612755  -7.0114652  97.5085 /T  77.5392
 2020-Apr-13 18:00  m  08 25 04.75 +28 58 29.5  13.26 0.08763495182903  -6.9919936  97.5541 /T  77.5497
 2020-Apr-14 00:00 *m  08 26 13.72 +28 39 48.5  13.23 0.08659269893862  -7.4441570  97.6370 /T  77.5257
 2020-Apr-14 06:00 *   08 27 15.11 +28 21 34.2  13.21 0.08550951343491  -7.4290470  97.6942 /T  77.5295
 2020-Apr-14 12:00     08 28 08.64 +28 01 53.2  13.18 0.08447217580496  -6.9366341  97.7278 /T  77.5541
 2020-Apr-14 18:00  m  08 29 12.45 +27 40 44.0  13.15 0.08348160333036  -6.9120119  97.8026 /T  77.5353
 2020-Apr-15 00:00 *m  08 30 26.85 +27 19 58.4  13.12 0.08245086551618  -7.3647941  97.9173 /T  77.4794
 2020-Apr-15 06:00 *   08 31 33.51 +26 59 35.4  13.10 0.08137934671439  -7.3452780  98.0058 /T  77.4517
 2020-Apr-15 12:00     08 32 32.10 +26 37 40.7  13.07 0.08035488865299  -6.8417116  98.0701 /T  77.4453
 2020-Apr-15 18:00  m  08 33 41.42 +26 14 13.0  13.04 0.07937862083272  -6.8103337  98.1784 /T  77.3928
 2020-Apr-16 00:00 *m  08 35 01.87 +25 51 03.7  13.01 0.07836258847465  -7.2631420  98.3294 /T  77.3002
 2020-Apr-16 06:00 *   08 36 14.41 +25 28 11.7  12.98 0.07730596123410  -7.2390445  98.4539 /T  77.2362
 2020-Apr-16 12:00     08 37 18.65 +25 03 43.0  12.95 0.07629770679256  -6.7229849  98.5536 /T  77.1940
 2020-Apr-16 18:00  m  08 38 34.10 +24 37 35.7  12.92 0.07533932537629  -6.6829240  98.7002 /T  77.1027
 2020-Apr-17 00:00 *m  08 40 01.29 +24 11 40.4  12.88 0.07434179151999  -7.1349173  98.8929 /T  76.9680
 2020-Apr-17 06:00 *   08 41 20.43 +23 45 56.0  12.85 0.07330390840347  -7.1059439  99.0589 /T  76.8620
 2020-Apr-17 12:00     08 42 31.00 +23 18 29.2  12.82 0.07231583023230  -6.5758398  99.1994 /T  76.7784
 2020-Apr-17 18:00  m  08 43 53.32 +22 49 18.0  12.78 0.07137961011301  -6.5247821  99.3899 /T  76.6425
 2020-Apr-18 00:00 *m  08 45 28.03 +22 20 10.9  12.75 0.07040511584491  -6.9747923  99.6303 /T  76.4594
 2020-Apr-18 06:00 *   08 46 54.58 +21 51 06.5  12.71 0.06939061089900  -6.9404970  99.8440 /T  76.3049
 2020-Apr-18 12:00     08 48 12.28 +21 20 14.0  12.68 0.06842748645520  -6.3945713 100.0315 /T  76.1736
 2020-Apr-18 18:00  m  08 49 42.27 +20 47 31.1  12.64 0.06751855743888  -6.3297467 100.2723 /T  75.9865
 2020-Apr-19 00:00 *m  08 51 25.42 +20 14 42.5  12.60 0.06657256679193  -6.7761813 100.5674 /T  75.7477
 2020-Apr-19 06:00 *m  08 53 00.31 +19 41 46.5  12.56 0.06558704071073  -6.7359313 100.8361 /T  75.5374
 2020-Apr-19 12:00     08 54 26.05 +19 06 56.8  12.53 0.06465463856261  -6.1721836 101.0775 /T  75.3511
 2020-Apr-19 18:00  m  08 56 04.65 +18 30 10.6  12.49 0.06377917547304  -6.0902986 101.3756 /T  75.1055
 2020-Apr-20 00:00 *m  08 57 57.26 +17 53 06.9  12.45 0.06286827998344  -6.5310271 101.7331 /T  74.8033
 2020-Apr-20 06:00 *m  08 59 41.57 +17 15 44.0  12.41 0.06191851625481  -6.4839723 102.0646 /T  74.5289
 2020-Apr-20 12:00     09 01 16.38 +16 36 21.9  12.37 0.06102381022325  -5.9002154 102.3675 /T  74.2798
 2020-Apr-20 18:00     09 03 04.64 +15 54 57.8  12.33 0.06018924637099  -5.7974057 102.7307 /T  73.9679
 2020-Apr-21 00:00 *m  09 05 07.88 +15 13 02.7  12.28 0.05932139237950  -6.2296402 103.1586 /T  73.5937
 2020-Apr-21 06:00 *m  09 07 02.83 +14 30 34.1  12.24 0.05841559583075  -6.1747027 103.5614 /T  73.2466
 2020-Apr-21 12:00     09 08 47.89 +13 46 01.8  12.20 0.05756699504377  -5.5686640 103.9337 /T  72.9265
 2020-Apr-21 18:00     09 10 47.01 +12 59 23.9  12.15 0.05678224241252  -5.4404988 104.3694 /T  72.5402
 2020-Apr-22 00:00 *m  09 13 02.19 +12 11 59.4  12.11 0.05596696033889  -5.8606932 104.8760 /T  72.0857
 2020-Apr-22 06:00 *m  09 15 09.16 +11 23 45.4  12.06 0.05511499359474  -5.7966068 105.3582 /T  71.6574
 2020-Apr-22 12:00     09 17 05.79 +10 33 25.3  12.02 0.05432255850549  -5.1661413 105.8074 /T  71.2584
 2020-Apr-22 18:00     09 19 17.10 +09 40 58.8  11.97 0.05359819723014  -5.0077337 106.3226 /T  70.7907
 2020-Apr-23 00:00 *m  09 21 45.67 +08 47 29.4  11.93 0.05284678792353  -5.4115506 106.9148 /T  70.2484
 2020-Apr-23 06:00 *m  09 24 06.20 +07 52 52.8  11.88 0.05206035406702  -5.3369987 107.4833 /T  69.7316
 2020-Apr-23 12:00     09 26 15.87 +06 56 11.5  11.83 0.05133593882476  -4.6804750 108.0151 /T  69.2476
 2020-Apr-23 18:00     09 28 40.84 +05 57 28.2  11.79 0.05068430599700  -4.4867780 108.6142 /T  68.6934
 2020-Apr-24 00:00 *m  09 31 24.41 +04 57 26.4  11.74 0.05000990261528  -4.8692012 109.2964 /T  68.0587
 2020-Apr-24 06:00 *m  09 34 00.17 +03 55 59.5  11.69 0.04930258206060  -4.7831182 109.9550 /T  67.4490
 2020-Apr-24 12:00     09 36 24.51 +02 52 35.0  11.64 0.04865980204656  -4.1000457 110.5715 /T  66.8775
 2020-Apr-24 18:00     09 39 04.70 +01 47 21.2  11.60 0.04809486745783  -3.8664234 111.2549 /T  66.2361
 2020-Apr-25 00:00 *m  09 42 04.96 +00 40 36.5  11.55 0.04751224608911  -4.2221181 112.0262 /T  65.5092
 2020-Apr-25 06:00 *m  09 44 57.77 -00 27 49.6  11.50 0.04689924858546  -4.1242173 112.7731 /T  64.8080
 2020-Apr-25 12:00     09 47 38.49 -01 37 57.6  11.46 0.04635312824658  -3.4161397 113.4703 /T  64.1525
 2020-Apr-25 18:00     09 50 35.53 -02 49 30.6  11.42 0.04589000689071  -3.1392715 114.2311 /T  63.4301
 2020-Apr-26 00:00 *m  09 53 54.23 -04 02 40.6  11.37 0.04541498481156  -3.4632729 115.0827 /T  62.6193
 2020-Apr-26 06:00 *m  09 57 05.94 -05 17 43.6  11.32 0.04491244828545  -3.3548007 115.9074 /T  61.8365
 2020-Apr-26 12:00     10 00 04.79 -06 34 02.2  11.28 0.04447858903255  -2.6263577 116.6720 /T  61.1095
 2020-Apr-26 18:00     10 03 20.26 -07 51 06.6  11.24 0.04413254399136  -2.3054034 117.4936 /T  60.3221
 2020-Apr-27 00:00 *   10 06 59.08 -09 09 44.1  11.20 0.04378082531666  -2.5941036 118.4061 /T  59.4461
 2020-Apr-27 06:00 *m  10 10 31.49 -10 30 19.1  11.16 0.04340453278143  -2.4786645 119.2868 /T  58.6028
 2020-Apr-27 12:00     10 13 50.12 -11 51 31.2  11.12 0.04309770832345  -1.7384954 120.0944 /T  57.8279
 2020-Apr-27 18:00     10 17 25.46 -13 12 34.4  11.09 0.04288259985805  -1.3762080 120.9492 /T  57.0026
 2020-Apr-28 00:00 *   10 21 25.84 -14 34 54.2  11.05 0.04266806406403  -1.6283861 121.8913 /T  56.0920
 2020-Apr-28 06:00 *m  10 25 20.50 -15 59 07.2  11.01 0.04243161773700  -1.5124554 122.7942 /T  55.2211
 2020-Apr-28 12:00     10 29 00.28 -17 23 08.7  10.98 0.04226390532313  -0.7733838 123.6096 /T  54.4330
 2020-Apr-28 18:00     10 32 56.54 -18 45 52.9  10.96 0.04219027776170  -0.3766106 124.4599 /T  53.6066
 2020-Apr-29 00:00 *   10 37 19.46 -20 09 25.0  10.93 0.04212297716126  -0.5940245 125.3906 /T  52.7017
 2020-Apr-29 06:00 *m  10 41 37.43 -21 34 38.4  10.90 0.04203576557635  -0.4866505 126.2731 /T  51.8452
 2020-Apr-29 12:00  m  10 45 39.20 -22 58 46.6  10.88 0.04201462480671   0.2353954 127.0543 /T  51.0851
 2020-Apr-29 18:00     10 49 56.75 -24 20 22.8  10.86 0.04208792184707   0.6563590 127.8577 /T  50.2993
 2020-Apr-30 00:00 *   10 54 42.39 -25 42 09.2  10.84 0.04217235157556   0.4692759 128.7326 /T  49.4438
 2020-Apr-30 06:00 *m  10 59 23.91 -27 05 20.8  10.83 0.04223792587550   0.5578330 129.5504 /T  48.6454
 2020-Apr-30 12:00  m  11 03 47.64 -28 26 37.2  10.81 0.04236486076025   1.2462063 130.2563 /T  47.9537
 2020-Apr-30 18:00     11 08 25.90 -29 44 09.9  10.81 0.04258440856149   1.6794554 130.9743 /T  47.2467
 2020-May-01 00:00 *   11 13 33.32 -31 01 12.3  10.80 0.04281869605085   1.5168099 131.7545 /T  46.4790
 2020-May-01 06:00 *m  11 18 37.41 -32 19 24.5  10.79 0.04303418095820   1.5771320 132.4705 /T  45.7751
 2020-May-01 12:00  m  11 23 21.90 -33 35 03.8  10.79 0.04330452462285   2.2173969 133.0701 /T  45.1827
 2020-May-01 18:00     11 28 18.95 -34 46 00.0  10.79 0.04366371246935   2.6517617 133.6761 /T  44.5808
 2020-May-02 00:00 *   11 33 45.75 -35 55 49.1  10.79 0.04404007025513   2.5077645 134.3364 /T  43.9260
 2020-May-02 06:00 *m  11 39 09.92 -37 06 37.8  10.80 0.04439685276087   2.5331318 134.9288 /T  43.3384
 2020-May-02 12:00  m  11 44 12.44 -38 14 33.0  10.80 0.04480076216992   3.1153400 135.4071 /T  42.8602
 2020-May-02 18:00     11 49 24.87 -39 17 04.8  10.82 0.04528834426197   3.5422341 135.8911 /T  42.3736
 2020-May-03 00:00 *   11 55 06.98 -40 18 00.3  10.83 0.04579458609282   3.4123612 136.4237 /T  41.8396
 2020-May-03 06:00 *m  12 00 47.06 -41 19 52.2  10.84 0.04627997371172   3.3996270 136.8884 /T  41.3727
 2020-May-03 12:00  m  12 06 03.32 -42 18 48.5  10.85 0.04680420954843   3.9191413 137.2471 /T  41.0074
 2020-May-03 18:00     12 11 26.18 -43 12 01.2  10.87 0.04740619942338   4.3333008 137.6151 /T  40.6304
 2020-May-04 00:00 *   12 17 17.97 -44 03 17.9  10.89 0.04802772023556   4.2146793 138.0280 /T  40.2098
 2020-May-04 06:00 *m  12 23 08.20 -44 55 34.1  10.91 0.04862693192424   4.1640227 138.3759 /T  39.8533
 2020-May-04 12:00  m  12 28 32.49 -45 45 08.3  10.93 0.04925678189842   4.6209412 138.6296 /T  39.5870
 2020-May-04 18:00     12 33 59.62 -46 28 56.8  10.95 0.04995830929683   5.0201380 138.8986 /T  39.3035
 2020-May-05 00:00 *   12 39 54.30 -47 10 38.3  10.98 0.05067991263840   4.9112956 139.2100 /T  38.9788
 2020-May-05 06:00 *   12 45 47.82 -47 53 26.9  11.00 0.05137782505286   4.8252793 139.4607 /T  38.7138
 2020-May-05 12:00  m  12 51 13.54 -48 33 57.6  11.03 0.05209867393416   5.2230943 139.6307 /T  38.5261
 2020-May-05 18:00  m  12 56 38.19 -49 08 54.5  11.06 0.05288539176139   5.6073141 139.8224 /T  38.3153
 2020-May-06 00:00 *   13 02 28.52 -49 41 40.5  11.08 0.05369261120627   5.5076658 140.0546 /T  38.0652
 2020-May-06 06:00 *   13 08 18.10 -50 15 43.0  11.11 0.05447497123376   5.3901510 140.2309 /T  37.8699
 2020-May-06 12:00  m  13 13 38.51 -50 47 57.3  11.14 0.05527332015790   5.7343093 140.3395 /T  37.7395
 2020-May-06 18:00  m  13 18 54.11 -51 14 58.9  11.17 0.05613224871646   6.1048651 140.4756 /T  37.5806
 2020-May-07 00:00 *   13 24 33.26 -51 39 50.7  11.20 0.05701210313164   6.0142341 140.6501 /T  37.3844
 2020-May-07 06:00 *   13 30 12.16 -52 06 08.3  11.23 0.05786619159824   5.8695039 140.7735 /T  37.2385
 2020-May-07 12:00  m  13 35 21.16 -52 31 09.0  11.26 0.05873016674173   6.1662534 140.8405 /T  37.1463
 2020-May-07 18:00  m  13 40 22.05 -52 51 22.7  11.30 0.05965006258525   6.5250852 140.9396 /T  37.0216
 2020-May-08 00:00 *   13 45 44.35 -53 09 30.9  11.33 0.06059135824261   6.4433798 141.0749 /T  36.8618
$$EOE
*******************************************************************************************************
Column meaning:
 
TIME

  Times PRIOR to 1962 are UT1, a mean-solar time closely related to the
prior but now-deprecated GMT. Times AFTER 1962 are in UTC, the current
civil or "wall-clock" time-scale. UTC is kept within 0.9 seconds of UT1
using integer leap-seconds for 1972 and later years.

  Conversion from the internal Barycentric Dynamical Time (TDB) of solar
system dynamics to the non-uniform civil UT time-scale requested for output
has not been determined for UTC times after the next July or January 1st.
Therefore, the last known leap-second is used as a constant over future
intervals.

  Time tags refer to the UT time-scale conversion from TDB on Earth
regardless of observer location within the solar system, although clock
rates may differ due to the local gravity field and no analog to "UT"
may be defined for that location.

  Any 'b' symbol in the 1st-column denotes a B.C. date. First-column blank
(" ") denotes an A.D. date. Calendar dates prior to 1582-Oct-15 are in the
Julian calendar system. Later calendar dates are in the Gregorian system.

  NOTE: "n.a." in output means quantity "not available" at the print-time.
 
SOLAR PRESENCE (OBSERVING SITE)
  Time tag is followed by a blank, then a solar-presence symbol:

        '*'  Daylight (refracted solar upper-limb on or above apparent horizon)
        'C'  Civil twilight/dawn
        'N'  Nautical twilight/dawn
        'A'  Astronomical twilight/dawn
        ' '  Night OR geocentric ephemeris

LUNAR PRESENCE (OBSERVING SITE)
  The solar-presence symbol is immediately followed by a lunar-presence symbol:

        'm'  Refracted upper-limb of Moon on or above apparent horizon
        ' '  Refracted upper-limb of Moon below apparent horizon OR geocentric
             ephemeris
 
 R.A._____(ICRF)_____DEC =
  Astrometric right ascension and declination of the target center with
respect to the observing site (coordinate origin) in the reference frame of
the planetary ephemeris (ICRF). Compensated for down-leg light-time delay
aberration.

  Units: RA  in hours-minutes-seconds of time   (HH MM SS.ff)
         DEC in degrees-minutes-seconds of arc  (sDD MN SC.f)
 
 APmag =
   Asteroid's approximate apparent visual magnitude from the standard
IAU H-G magnitude relationship:
   APmag = H + 5*log10(delta) + 5*log10(r) - 2.5*log10((1-G)*phi1 + G*phi2).
For solar phase angles > 90 deg, the error could exceed 1 magnitude. For phase
angles > 120 degrees, output values are rounded to the nearest integer to
indicate error could be large and unknown.
   Units: MAGNITUDE
 
 delta  deldot =
   Range ("delta") and range-rate ("delta-dot") of target center with respect
to the observer at the instant light seen by the observer at print-time would
have left the target center (print-time minus down-leg light-time); the
distance traveled by a light ray emanating from the center of the target and
recorded by the observer at print-time. "deldot" is a projection of the
velocity vector along this ray, the light-time-corrected line-of-sight from
the coordinate center, and indicates relative motion. A positive "deldot"
means the target center is moving away from the observer (coordinate center).
A negative "deldot" means the target center is moving toward the observer.
Units: AU and KM/S
 
 S-O-T /r =
    Sun-Observer-Target angle; target's apparent SOLAR ELONGATION seen from
the observer location at print-time. Angular units: DEGREES

    The '/r' column indicates the target's apparent position relative to
the Sun in the observer's sky, as described below:

    For an observing location on the surface of a rotating body
(considering its rotational sense):

    /T indicates target TRAILS Sun (evening sky; rises and sets AFTER Sun)
    /L indicates target LEADS Sun  (morning sky; rises and sets BEFORE Sun)

For an observing point NOT on a rotating body (such as a spacecraft), the
"leading" and "trailing" condition is defined by the observer's
heliocentric orbital motion: if continuing in the observer's current
direction of heliocentric motion would encounter the target's apparent
longitude first, followed by the Sun's, the target LEADS the Sun as seen by
the observer. If the Sun's apparent longitude would be encountered first,
followed by the target's, the target TRAILS the Sun.

NOTE: The S-O-T solar elongation angle is numerically the minimum
separation angle of the Sun and target in the sky in any direction. It
does NOT indicate the amount of separation in the leading or trailing
directions, which are defined in the equator of a spherical coordinate
system.
 
 S-T-O =
   "S-T-O" is the Sun->Target->Observer angle; the interior vertex angle at
target center formed by a vector to the apparent center of the Sun at
reflection time on the target and the apparent vector to the observer at
print-time. Slightly different from true PHASE ANGLE (requestable separately)
at the few arcsecond level in that it includes stellar aberration on the
down-leg from target to observer.  Units: DEGREES


 Computations by ...
     Solar System Dynamics Group, Horizons On-Line Ephemeris System
     4800 Oak Grove Drive, Jet Propulsion Laboratory
     Pasadena, CA  91109   USA
     Information: http://ssd.jpl.nasa.gov/
     Connect    : telnet://ssd.jpl.nasa.gov:6775  (via browser)
                  telnet ssd.jpl.nasa.gov 6775    (via command-line)
     Author     : Jon.D.Giorgini@jpl.nasa.gov





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