User:Wikibob/Sandbox3
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Attempt at getting Deimos transit info from JPL Horizons.
Deciphering timestamps from Mars Rover image filenames
[1] Explains the image filename fields, and we're interested in characters:
3 to 11 Spacecraft clock
This is the number of seconds since January 1, 2000
at 11:58:55.816 UTC.
So from the Sol 30 March 4 Deimos transit image filenames.
If I've not made a miscalculation, and if Opportunity's onboard clock was correct, then UTC times for the 4 Deimos transit images were:
Mar 4 03:03:43 = Image 1 showing mid-transit Mar 4 03:03:53 = Image 2 still in transit Mar 4 03:04:03 = Image 3 approaching third contact Mar 4 03:04:13 = Image 4 possibly between third and fourth contact
Compare with the 3 Opportunity images mentioned in IAU circular 08298:
Mar 4 03:03:56 Mar. 4.12773 UT Mar 4 03:04:06 Mar. 4.12785 Mar 4 03:04:16 Mar. 4.12819
Some calculations, MER-0 is 0 seconds for the Rover clock:
UTC decimal HH:MM:SS Julian Day secs since MER-0 ----------------------------------------------------------- 2000 Jan 1 noon = 2451545.0 64.184 2004 Mar 3 noon = 2453068.0 131587264.184 =1523 days +64secs 2004 Mar 4.127581 03:03:43 2453068.627581 131641487.0 = Image 1 2004 Mar 4.127697 03:03:53 2453068.627697 131641497.0 = Image 2 2004 Mar 4.127812 03:04:03 2453068.627812 131641507.0 = Image 3 2004 Mar 4.127928 03:04:13 2453068.627928 131641517.0 = Image 4
more notes...
Local Time Filename Seconds 10:28:17 1P131641487ESF0544P2665R8M1 131641487 10:28:27 1P131641497ESF0544P2666R8M1 131641497
See Transit of Deimos from Mars and User_talk:Curps.
2 198.05 miles = 3 537.41858 kilometers 564.48 miles = 908.442501 kilometers
Using Mars Rover Spirit's coords: -175.4833, 3537.41, 908.44
Select ... [E]phemeris, [F]tp, [M]ail, [R]edisplay, ?, <cr>: 402
*******************************************************************************
Revised: May 04, 1999 Deimos / (Mars) 402
SATELLITE PHYSICAL PROPERTIES:
Radius (km) = 7.8 x 6.0 x 5.1 Density (g cm^-3) = 1.76 +- 0.30
Mass (10^20 kg ) = 1.80 (10^-5) Geometric Albedo = 0.06
(+- 0.15) V(1,0) = +12.89
SATELLITE ORBITAL DATA:
Semi-major axis, a (km) = 23.4632(10^3) Orbital period = 1.262441 d
Eccentricity, e = 0.00033 Rotational period = Synchronous
Inclination, i (deg) = 1.791
*******************************************************************************
Select ... [E]phemeris, [F]tp, [M]ail, [R]edisplay, ?, <cr>: e
Observe, Elements, Vectors [o,e,v,?] : o
Coordinate center [ <id>,coord,geo ] : Spirit@499
# E. Lon DXY DZ Observatory Name
--- -------- ------- ------- ----------------
-175.4833 +219805 -056448 Spirit Landing Site (MER) / Gusev
Confirm selected station [ y/n ] --> y
Starting UT [ex: 1976-Jun-02 00:02 ] : 2004-Mar-09 15:50
Ending UT [ex: 2025-Jan-10 23:56 ] : 2004-Mar-09 15:58
Output interval [ex: 10m, 1h, 1d, ? ] : 1m
Current output table defaults --
Reference frame = ICRF/J2000.0
Time zone correction = UT+00:00
Time format = CAL
Time digits output = MIN
R.A. format = HMS
RA/DEC extra precision= NO
Apparent coord. type = AIRLESS
Range units = AU
Suppress range-rate = NO
Minimum elevation = -90.0
Maximum airmass = 38.0000
Rise-Transit-Set only = NO
Skip daylight = NO
Solar elong. cut-off = 0,180
CSV spreadsheet output= NO
Table quantities = A
Accept default output [ cr=(y), n, ?] :
Select table quantities [ <#,#..>, ?] : 4,5,13,23,34
Working ...
*******************************************************************************
Ephemeris / PORT_LOGIN Thu Jun 17 16:17:25 2004 Pasadena, USA / Horizons
*******************************************************************************
Target body name: Deimos (402) {source: MAR033.DE405}
Center body name: Mars (499) {source: DE-0406LE-0406}
Center-site name: Spirit Landing Site (MER) / Gusev
*******************************************************************************
Start time : A.D. 2004-Mar-09 15:50:00.0000 UT
Stop time : A.D. 2004-Mar-09 15:58:00.0000 UT
Step-size : 1 minutes
*******************************************************************************
Center geodetic : -175.483300, -14.5667, -0.0{E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: -175.483300, 3288.2360, -844.4{E-lon(deg),Dxy(km),Dz(km)}
Center pole/equ : IAU_MARS {East-longitude -}
Center radii : 3396.2 x 3396.2 x 3376.2 km {Equator, meridian, pole}
Target pole/equ : IAU_DEIMOS {East-longitude -}
Target radii : 7.5 x 6.1 x 5.2 km {Equator, meridian, pole}
Target primary : Mars {source: DE-0406LE-0406}
Interfering body: PHOBOS (Req= 13.400) km {source: MAR033.DE405}
Deflecting body : Sun {source: DE-0406LE-0406}
Deflecting GM : 1.3271E+11 km^3/s^2
Atmos refraction: NO (AIRLESS)
RA format : HMS
Previous attempt using DXY and DZ as KM when they were miles.
telnet ssd.jpl.nasa.gov 6775
...
Horizons> 402
*******************************************************************************
Revised: May 04, 1999 Deimos / (Mars) 402
SATELLITE PHYSICAL PROPERTIES:
Radius (km) = 7.8 x 6.0 x 5.1 Density (g cm^-3) = 1.76 +- 0.30
Mass (10^20 kg ) = 1.80 (10^-5) Geometric Albedo = 0.06
(+- 0.15) V(1,0) = +12.89
SATELLITE ORBITAL DATA:
Semi-major axis, a (km) = 23.4632(10^3) Orbital period = 1.262441 d
Eccentricity, e = 0.00033 Rotational period = Synchronous
Inclination, i (deg) = 1.791
*******************************************************************************
Select ... [E]phemeris, [F]tp, [M]ail, [R]edisplay, ?, <cr>: e
Observe, Elements, Vectors [o,e,v,?] : o
Use previous center [ cr=(y), n, ? ] : n
Coordinate center [ <id>,coord,geo ] : c@499
Cylindrical or Geodetic input [ c,g ] : c
Input units must be DEGREES and KILOMETERS --
Specify cylindr {E. Long, DXY, DZ} : -175.4833, +3198.05, -0564.48
Starting UT [ex: 1976-Jun-02 00:02 ] : 2004-Mar-09 15:50
Ending UT [ex: 2025-Jan-10 23:56 ] : 2004-Mar-09 15:59
Output interval [ex: 10m, 1h, 1d, ? ] : 1m
*******************************************************************************
Ephemeris / PORT_LOGIN Thu Jun 17 15:18:18 2004 Pasadena, USA / Horizons
*******************************************************************************
Target body name: Deimos (402) {source: MAR033.DE405}
Center body name: Mars (499) {source: DE-0406LE-0406}
Center-site name: (User Defined Site)
*******************************************************************************
Start time : A.D. 2004-Mar-09 15:50:00.0000 UT
Stop time : A.D. 2004-Mar-09 15:59:00.0000 UT
Step-size : 1 minutes
*******************************************************************************
Center geodetic : -175.483300, -10.1318, -148.0{E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: -175.483300, 3198.0500, -564.4{E-lon(deg),Dxy(km),Dz(km)}
Center pole/equ : IAU_MARS {East-longitude -}
Center radii : 3396.2 x 3396.2 x 3376.2 km {Equator, meridian, pole}
Target pole/equ : IAU_DEIMOS {East-longitude -}
Target radii : 7.5 x 6.1 x 5.2 km {Equator, meridian, pole}
Target primary : Mars {source: DE-0406LE-0406}
Interfering body: PHOBOS (Req= 13.400) km {source: MAR033.DE405}
Deflecting body : Sun {source: DE-0406LE-0406}
Deflecting GM : 1.3271E+11 km^3/s^2
Atmos refraction: NO (AIRLESS)
RA format : DEG
< Scroll & Page: space, <cr>, <b>ack, OR arrow keys. <q> ends display. > 20%
Time format : CAL
RTS-only print : NO
EOP file : eop.040617.p040908
EOP coverage : DATA-BASED 1962-JAN-20 TO 2004-JUN-17. PREDICTS-> 2004-SEP-07
Units conversion: 1 AU= 149597870.691 km, c= 299792.458 km/s, 1 day= 86400.0 s
Table cut-offs 1: Elevation (-90.0deg=NO ),Airmass n.a. , Daylight (NO )
Table cut-offs 2: Solar Elongation ( 0.0,180.0=NO )
*******************************************************************************
Date__(UT)__HR:MN:SS Azi_(a-appr)_Elev L_Ap_Sid_Time Ang-diam S-O-T /r
*******************************************************************************
$$SOE
2004-Mar-09 15:50:00 *x 235.1606 -74.2769 14.1024935262 116.462 130.0487 /T
2004-Mar-09 15:51:00 *x 235.0815 -74.3112 14.1187385252 116.459 130.2516 /T
2004-Mar-09 15:52:00 *x 235.0020 -74.3453 14.1349835243 116.456 130.4545 /T
2004-Mar-09 15:53:00 *x 234.9223 -74.3795 14.1512285233 116.454 130.6573 /T
2004-Mar-09 15:54:00 *x 234.8422 -74.4136 14.1674735223 116.451 130.8602 /T
2004-Mar-09 15:55:00 *x 234.7618 -74.4477 14.1837185213 116.448 131.0630 /T
2004-Mar-09 15:56:00 *x 234.6810 -74.4818 14.1999635203 116.446 131.2659 /T
2004-Mar-09 15:57:00 *x 234.6000 -74.5158 14.2162085193 116.443 131.4687 /T
2004-Mar-09 15:58:00 *x 234.5185 -74.5498 14.2324535183 116.441 131.6716 /T
2004-Mar-09 15:59:00 *x 234.4368 -74.5838 14.2486985174 116.438 131.8744 /T