Comet NEOWISE (C/2020 F3)


Chanan Greenberg
 

Hi All,

I just got an AP900 GTOCP2 from a friend. I used this mount 10 years ago and have forgotten a few of the basics. I was looking to track Comet Neowise and completely forgot how to figure out what Custom RA and Dec information to enter into the AP V2 ASCOM Driver window. I did visit the JPL Horizons website and downloaded the data but was not sure which data to use.

Hope someone will help me figure it out. I did once, for the life of me cannot remember what I did. 

Clear skies,
Chanan


Willie Strickland
 

I found myself in the same position last night.  Due to family commitments I have been absent from imaging for an extended period.  I thought I remembered as well, but when I entered the correction, the scope began a significant slew.  Oops.

Willie


Chanan Greenberg
 

This is a sample of the data I get from JPL
There is RA ICRF / Apparent RA and dRA*COS D  - I know there is an interface to newer versions that converts all this automatically via an interface. But i do not have that. Can someone help me figure out the custom RA and DA rate or at least how to calculate them?

*******************************************************************************
JPL/HORIZONS                 NEOWISE (C/2020 F3)           2020-Jul-19 17:55:59
Rec #:90004465 (+COV) Soln.date: 2020-Jul-18_14:19:12     # obs: 372 (113 days)
 
IAU76/J2000 helio. ecliptic osc. elements (au, days, deg., period=Julian yrs):
 
  EPOCH=  2459064.5 ! 2020-Aug-03.0000000 (TDB)    RMSW= n.a.
   EC= .9991691234351144   QR= .2946512233784272   TP= 2459034.1790709617
   OM= 61.00939569131192   W= 37.27847625028863    IN= 128.9374034572737
   A= 354.6269516206773    MA= .004474958062287851 ADIST= 708.9592520179763
   PER= 6678.2984358648    N= .000147586           ANGMOM= .013202626
   DAN= .32816             DDN= 2.87401            L= 35.4432405
   B= 28.1073672           MOID= .36253801         TP= 2020-Jul-03.6790709617
 
Comet physical (GM= km^3/s^2; RAD= km):
   GM= n.a.                RAD= n.a.
   M1=  10.7     M2=  14.9     k1=  17.75  k2=  5.      PHCOF=  .030
 
COMET comments 
1: soln ref.= JPL#14, data arc: 2020-03-27 to 2020-07-18
2: k1=17.75, k2=5., phase coef.=0.03;
*******************************************************************************
 
 
*******************************************************************************
Ephemeris / WWW_USER Sun Jul 19 17:55:59 2020 Pasadena, USA      / Horizons
*******************************************************************************
Target body name: NEOWISE (C/2020 F3)             {source: JPL#14}
Center body name: Earth (399)                     {source: DE431}
Center-site name: (user defined site below)
*******************************************************************************
Start time      : A.D. 2020-Jul-19 00:00:00.0000 UT
Stop  time      : A.D. 2020-Aug-19 00:00:00.0000 UT
Step-size       : 1 minutes
*******************************************************************************
Target pole/equ : No model available
Target radii    : (unavailable)                                           
Center geodetic : 238.110000,37.3378000,0.0000000 {E-lon(deg),Lat(deg),Alt(km)}
Center cylindric: 238.110000,5077.34335,3847.2668 {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 
RTS-only print  : NO       
EOP file        : eop.200717.p201008                                           
EOP coverage    : DATA-BASED 1962-JAN-20 TO 2020-JUL-17. PREDICTS-> 2020-OCT-07
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=  2459064.5 ! 2020-Aug-03.0000000 (TDB)    RMSW= n.a.         
   EC= .9991691234351144   QR= .2946512233784272   TP= 2459034.1790709617
   OM= 61.00939569131192   W= 37.27847625028863    IN= 128.9374034572737       
  Equivalent ICRF heliocentric equatorial cartesian coordinates (au, au/d):
   X=-8.321621038925854E-02  Y=-8.646020467729936E-01  Z= 3.618176019624061E-02
  VX=-1.306354356457230E-02 VY=-2.045458056181457E-02 VZ=-9.533388646221023E-03
Comet physical (GM= km^3/s^2; RAD= km):                               
   GM= n.a.                RAD= n.a.                                           
   M1=  10.7     M2=  14.9     k1=  17.75  k2=  5.      PHCOF=  .030           
************************************************************************************************************************************
 Date__(UT)__HR:MN     R.A._____(ICRF)_____DEC R.A.__(a-apparent)__DEC dRA*cosD d(DEC)/dt L_Ap_Sid_Time            delta      deldot
************************************************************************************************************************************
$$SOE
 2020-Jul-19 00:00 *m  09 01 50.18 +48 07 02.9 09 03 11.57 +48 02 20.9 543.8484  -35.6628 11 41 25.4736 0.71619678171961 -20.7392241
 2020-Jul-19 00:01 *m  09 01 51.08 +48 07 02.3 09 03 12.48 +48 02 20.3 543.8628  -35.7024 11 42 25.6378 0.71618846394532 -20.7348636
 2020-Jul-19 00:02 *m  09 01 51.99 +48 07 01.7 09 03 13.38 +48 02 19.7 543.8771  -35.7421 11 43 25.8021 0.71618014791953 -20.7305061


Worsel
 

Chanan

Do you have APCC Standard or Pro?  If you do, the included Horizons program will extract the JPL data and set up the mount for you.

Demos at https://www.astro-physics.info/index.htm?tech_support/software/apcc/apcc-download

See section 13 in Standard or Section 14 in Section in Pro

If you do not have APCC, then I am sure Ray can provide insight on how to use the Custom tracking rates.



Bryan


Chanan Greenberg
 

It is an AP900 connected via the AP V2 ASCOM Driver - it is not APCC standard or pro download from the AP website


On Sun, Jul 19, 2020 at 6:52 PM Worsel via groups.io <bryancashion=yahoo.com@groups.io> wrote:
Chanan

Do you have APCC Standard or Pro?  If you do, the included Horizons program will extract the JPL data and set up the mount for you.

Demos at https://www.astro-physics.info/index.htm?tech_support/software/apcc/apcc-download

See section 13 in Standard or Section 14 in Section in Pro

If you do not have APCC, then I am sure Ray can provide insight on how to use the Custom tracking rates.



Bryan


Ray Gralak
 

Hi Chanan,

Sorry but the AP V2 ASCOM driver only supports tracking rates for GTOCP3 control boxes with Rev S or later firmware.

You might try downloading my PulseGuide program from http://www.pulseguide.com.

-Ray Gralak
Author of APCC (Astro-Physics Command Center): https://www.astro-physics.com/apcc-pro
Author of PEMPro V3: https://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of chanan2009@gmail.com
Sent: Saturday, July 18, 2020 11:27 PM
To: main@ap-gto.groups.io
Subject: [ap-gto] Comet NEOWISE (C/2020 F3)

Hi All,

I just got an AP900 GTOCP2 from a friend. I used this mount 10 years ago and have forgotten a few of the
basics. I was looking to track Comet Neowise and completely forgot how to figure out what Custom RA and Dec
information to enter into the AP V2 ASCOM Driver window. I did visit the JPL Horizons website and downloaded
the data but was not sure which data to use.

Hope someone will help me figure it out. I did once, for the life of me cannot remember what I did.

Clear skies,
Chanan