ZTF moving target checker for short object lists.

• Python 3.5+
• astropy v2.0+
• requests
• astroquery 0.3.8
• sqlite3
• wget
• Montage and montage_wrapper, optional, for image reprojection with zproject

Create a file with your preferred locations for the database, log file, etc. in ~/.config/zchecker.config. To see the file format and current allowed configuration parameters::

$ zchecker --help

...
{
"database": "/path/to/zchecker.db",
"log": "/path/to/zchecker.log",
"user": "IRSA account user name",
"password": "IRSA account password",
"cutout path": "/path/to/cutout/directory",
"stack path": "/path/to/stack/directory"
}

1. (Optional) Make a list of objects: objects.list.

2. Update local database with ephemerides, specifying objects through the list or on the command line::

   zchecker eph-update objects.list --start=YYYY-MM-DD --end=YYYY-MM-DD

   zchecker eph-update "C/2017 Y1, C/2017 Y2" --start=YYYY-MM-DD --end=YYYY-MM-DD

   Broad date ranges are best. Ephemerides can be updated as the orbital elements are refined.

3. Alternatively, add ephemerides, but only if none are found in the time period, using the --add option::

   zchecker eph-update "C/2017 Y1" --add --start=YYYY-MM-DD --end=YYYY-MM-DD

4. Delete ephemerides from the database::

   zchecker clean-eph objects.list

   zchecker clean-eph objects.list --start=YYYY-MM-DD --end=YYYY-MM-DD

   zchecker clean-eph "C/2017 Y1, C/2017 Y2" --start=YYYY-MM-DD --end=YYYY-MM-DD

1. Update local database with ZTF observations from a date::

   zchecker ztf-update --date=YYYY-MM-DD

   Or to simply check the last night::

   zchecker ztf-update

2. List which nights are in local database::

   zchecker list-nights

3. Find observations of your targets from the last night::

   zchecker search

   For a specific date::

   zchecker search --date=YYYY-MM-DD

   Over a range of dates::

   zchecker search --start=YYYY-MM-DD --end=YYYY-MM-DD

   For all dates in the local database::

   zchecker search --full

   For a subset of targets saved to the file subset.list::

   zchecker search subset.list --full

   For a subset of targets specified on the command line::

   zchecker search "C/2017 AB5" --full

   zchecker search "C/2017 Y1,C/2017 Y2" --full

   Using a different V magnitude limit::

   zchecker search "C/2017 Y1,C/2017 Y2" --full --vlim=18

4. Clean the found object database and associated cutout files, if they exist::

   zchecker clean-found "C/2017 AB5"

   zchecker clean-found "C/2017 AB5" --start=YYYY-MM-DD --end=YYYY-MM-DD

5. Download cutouts around each found target::

   zchecker download-cutouts

6. Reproject downloaded cutouts to align projected velocity vectors and comet-Sun vectors along the +x axis::

   zproject

The obs and nights tables joined by nightid.

Coarse ephemerides for objects of interest.

The combination of desg and jd is unique in the table.

Objects with ephemeris positions covered by ZTF.

The combination of desg and pid is unique in the table.

The found and obs tables joined together by product ID, with the addition of url for a URL to a cutout centered on the ephemeris position. Append '&size=5arcmin` or similar to specify the cutout size.