TESS

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TESS

This page summarizes some aspects of the processing of TESS full-frame images using the tools provided by the FITSH package.

How to start, what do you need

  • A local copy of the calibrated full-frame TESS FFIs. These files can directly be retrieved from MAST, using the link of http://archive.stsci.edu/tess/bulk_downloads/bulk_downloads_ffi-tp-lc-dv.html. Here, go for the section Full Frame Images and, within then, take look at Calibrated FFIs. There are the download scripts named tesscurl_sector_1_ffic.sh, tesscurl_sector_2_ffic.sh, ... one for each sector.
    • The simplest solution is to use these scripts directly to retrieve the files. Since these scripts retrieve just a bunch of files (without any particular directory tree), you may create some filesystem-level standard for the storage. A recommended directory tree can be /pub/tess/ffi/cal/s1, /pub/tess/ffi/cal/s2, ... for TESS Sectors 1, 2, ... respectively.
    • In each of these directories, there will be ~15500 ... ~20600 files. Each of these files has a size of 34 megabytes - therefore, in total, 520 ... 700 gigabytes for are needed for each directory. Up to Sector 12, the total volume is 7.6 terabytes.
    • These file-by-file retrieval tesscurl_sector_*_ffic.sh scripts are not so optimal in many sense. There might be a need of a day (20 ... 28 hours) to retrieve a single sector. However, you can speed up this process by using these instructions.
  • A local copy of the DR2 data release of the GAIA catalogue. The full catalogue is available via the GAIA archive, most importantly from this directory: http://cdn.gea.esac.esa.int/Gaia/gdr2/.
    • One can create a similar filesystem hierarchy like for the calibrated TESS FFI archives, e.g. it can be put into the directory /pub/gaia/gdr2
    • The total size of the GAIA DR2 (GDR2) catalogue is around 567 gigabytes: this amount of data has exactly the same order of magnitude like a single TESS sector, so it indeed worth to download it.
    • The 98.8% of the GAIA DR2 data volume is in the point source catalog and in the format of gzipped CSV files. Following the aforementioned standard, these files are then located in the directory /pub/gaia/gdr2/gaia_source/csv. Here, there are 61234 *.csv.gz files, named and organized according to their HEALPix coverage
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