Astrometry

For this example, I am using data taken on the Mauna Kea 88" on the 19th and 20th of May, 2001.

astrom.pro: Begin by running doast.pro with the /nodisplay flag. The following items in doast need to be updated:

pro doast,num1,num2,TWOSTAR=twostar,NOOBJ=noobj,OBJNAME=objname, $
KILLREF=killref,EDIT=edit,NEWCAT=newcat, $
NODISPLAY=nodisplay, MINREFRESH=minrefresh

if badpar(twostar,[0,2,3],0,caller='siteast: (twostar) ',default=0) then return
; skip interactive selection of objects by default
if badpar(noobj,[0,2,3],0,caller='siteast: (noobj) ',default=1) then return
if badpar(num2,[0,2,3],0,caller='siteast: (num2) ',default=num1) then return
if badpar(minrefresh,[0,2,3],0,caller='siteast: (minrefresh) ',default=1) then return

root='010519'
for num=num1,num2 do begin
astrom,binfac=4,gain=1.74,objname=objname,key='../mko88.key', $
/noremind,objrad=5,path='/gryll/data8/buie/rawfits/mko/010519', $
/roam,center=2,nodisplay=nodisplay,minrefresh=minrefresh, $
root,num,noobj=noobj,maxphotsig=66000.0, $
twostar=twostar,edit=edit,newcat=newcat, $
plastfile='none', $
killref=killref ; ,catpath='/pub/home/koehn/starnet/dist/USNO-A2.0'
endfor

end

The file astrom.inf contains information about the orientation and plate scale of the detector. This should be obtained from previous observations using that telescope and should be in the same directory where you run doast.

doast generates the file astrom.err, which gives warnings of poor star coverage. If there is poor coverage on three or more enneanants, astrom will abort and move on to the next file. For those files, run doast with the flags /killref and /newcat. If there is still bad coverage, run doast with the flags /killref and /twostar to interactively obtain the reference star fit.

Astrom will create .ast files for each object that is flagged with a "y".

astcol.pro: From the directory with .ast files, type

IDL> astcol,obs=568

where 568 is the observatory code for Mauna Kea. A file is created called /gryll/data1/buie/astrometry/mko0105.ted. Next, type

% mkdir lplast
% cd lplast
% cp /gryll/data1/buie/astrometry/0105mko.ted .
% /info/yoda1/bernstein/kbomatch

This program will ask you for the input file, 0105mko.ted. It will go through each linked object and ask you to verify the match. You should check that the orbit elements don't change by a huge amount when the new observations are added. Residuals and the RMS should be mostly less than 1 arcsec. The program creates a file called kbomatch.xrft. Type

% cp kbomatch.xrft ../lplast.xrft
% cd ..
IDL> astcol,obs=568

The program will ask if you want to setup the final ID codes; type "no." Look at the file lplast.xrft to see that all objects you thought should be linked up were. At this point, use ephcheck.pro to see if a non-linked object has a sensible orbit. To use ephcheck, type

IDL>ephcheck,'Aobject',568,'ast file'
e.g.,
IDL>ephcheck,'A99HT11',586,'2060800.ast'

You can edit the lplast.xrft file carefully, not adding any blank lines anywhere. Next, run astcol again, and say "yes" when it asks if you want to setup final ID codes. Next, use the template /gryll/data1/buie/astrometry/header to create a header for the .ted file. The last step is to convert the .ted file into the MPC's format by typing

% mar2pack

from the astrometry directory.