BAA Winchester Weekend - Step 5 - Text Files
We now have quite a lot of information about comet 70P, including measurements of multibox magnitudes, MPC positions and magnitudes, a visual equivalent magnitude and an estimate of coma size. Step 5 concerns how to get the information into the formats required by: - Minor Planet Center (MPC); the position and single magnitude estimate for each of the three measurements selected in FoCAs - COBS; the visual equivalent magnitude and estimate of coma size - Cometas; the multibox magnitude estimates and (in addition) MPC and COBS information (as above) Each of the bodies above maintains a database that users can consult at will and each requires that data submitted to it be submitted in a very specific format that its computers can handle automatically. Again, Roger Dymock has provided information on the BAA webpage referred to in Stage 1 and each of the bodies noted above (see links below) provides additional information. We will continue here using the information that I used at Winchester. The good news is that the databases require information in text file format, so all you need to manipulate the information is the basic text editor that comes free with Windows. MPC FoCAs produces the information in the format required but there’s one quirk that I have never been able to resolve. For some reason (at least with my setup) FoCAs inserts the catalogue used on the same line as the measurements required by the MPC. If I were to submit the information in this format, the MPC would reject it. So I have to manually delete the first 12 columns in each measurement as shown in the “before” and “after” shots below: Once the information has been tidied up I save the final version as a text file called “MPC report data.txt”. The information actually goes to the MPC as an email - I cut and paste the text from the file into an email with html disabled as the MPC prefers plain text emails - but the text file is required by Cometas (see below) and it’s always good to have a copy in case of later queries. Note that you will need your own observer code with the MPC to submit data to it, guidance is available here: COBS Kphot produces most of the information required but for speed I tend to keep a standard template in a text file called “COBS-ICQ kphot visual mag estimate.txt” and then paste in the Kphot information, estimate of coma size and other observer specific data as required. The data required for 70P is shown in the screen shot below: You will recognise much of the data from Steps 3 and 4, the additional data is observer specific (name, equipment used, image scale etc) so you will need to work yours out independently, but guidance is available through Roger Dymock’s BAA page and on the COBS website referred to earlier. COBS differers from MPC and Cometas in that it requires that information be input to its systems online at the website referred to earlier, rather than by email. There are two choices, either through an online form on a comet by comet basis or through bulk posting. I usually bundle together measurements and use the bulk posting method but both work well. Cometas For speed I tend to keep a standard template in a text file called “Multibox report data.txt” and then paste in the MPC data (as above) and additional multibox magnitude estimates as shown in the screen shot below: Once complete I cut and paste the text from the file into an email to Cometas along with three text files (as attachments): - MPC report data.txt - Multibox report data.txt - COBS-ICQ kphot visual mag estimate.txt That’s the end of Step 5. Final thoughts... Applying the techniques the first few times feels cumbersome, but as with most things (like driving a car) the more you do it, the easier it becomes. Start by getting data that you are comfortable with. As mentioned previously, you don’t need pretty images or excellent guiding, but it is important to reduce the images using bias, dark and flat frames. The specific formats required by MPC, COBS and Cometas are necessary to enable their computers to handle the data automatically. The first time you use them you will need to spend some time working out the codes for your specific system (e.g. things like image scale, focal length etc.) But the good news is that once you have done this for the first time, if you continue to use the same equipment the data will remain the same. So you can make use of templates in simple text files and drop in new measurements to speed up submission. In fact, once you get into the swing of it, you can complete the entire process for a comet in less than 10 minutes and contribute meaningful data to the scientific community. Good luck!
Hills Observatory: 1 January 2013 to 30 March 2020