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Troubleshooting - What to do if your Firewall prevents you from connecting to the USNO-B1.0 catalogue

This situation arises when your firewall is set up so that you need to input a password before accessing the internet. If this is the case, you will need to download the portion of the USNO-B1.0 catalogue that corresponds to your image and then tell Astrometrica where to look for this file.

1. Find out the central coordinates of your image.

   You need these coordinates to extract the stars around this position from the USNO-B1 catalogue. Select Images » Display Header...

   This will return the header information for the Faulkes Telescope image. The header of the image contains a wealth of information about where, when and how the image was taken. Scroll down until you find the RA and DEC entries and note these positions down.
   

2. Download the portion of the USNO-B1.0 catalogue that corresponds to your Faulkes Telescope Images.

   The USNO-B1.0 catalogue can be found at:

   http://www.nofs.navy.mil/data/fchpix/

   The fields you need to fill out are displayed in the following image and highlighted in red:
   

   Now you need to input some data and make some changes to the default settings:

   • Field Name : enter the name of the asteroid under investigation
   • RA : enter the RA obtained from the header above
   • Dec : enter the Dec obtained from the header above
   • Rectangle of Size : input 6 and 6. The field of view (size of the image) of the Faulkes Telescope is about 5 arcminutes by 5 arcminutes. By selecting 6 arcminutes by 6 arcminutes here, you can be assured that you will have all the stars in the image.
   • Make sure you select USNO-B1.0 under Catalogue(s)
   • Make sure you uncheck the Finder Charts box

   Once all this is complete, click on Retrieve Data. You will be returned a page similar to the following:
   

   Right-click on the link to the USNO-B1.0 Star List and Save Target to the desktop of your computer. Extract the data file from the compressed file you have just downloaded (right-click on file and select Extract files...). Rename this extracted file to be USNO-B.dat and move this file to your Astrometrica directory.

3. Tell Astrometrica where to find this file.

   Select File » Settings... Go to the Environment Tab and in the Star Catalogue field, input the directory where you have placed the USNO-B.dat file.
   

4. Tell Astrometrica not to connect to the internet.

   To do this, you have to manually edit the Astrometrica.cfg file in your Astrometrica directory. Open this file with Wordpad or a similar program.

   Add the following line to the end of the [Settings] section of this configuration file (it must be on a new line):
   

   USNOMode=1

   Save the configuration file and restart Astrometrica. Astrometrica will now use this file to match the stars in your images to the stars in the USNO-B1.0 catalogue and you should now have no troubles.

Note: You have to download a new file from the web version of the USNO-B1.0 catalogue, rename it to be USNO-B.dat and place it in the correct directory for each asteroid you are analysing.

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