Fermi LAT Schema

GCN notices are machine-readable packets that are available in different formats; text, binary, and VOEvent. For each event and instrument-specific, different types of notices are available. Each type of notice contains different properties.

In this example, Fermi-LAT GCN notice is used as a text file, then schema and example are created as following steps:

• Extract the URL of the GCN notice text file from the HTML table at: https://gcn.gsfc.nasa.gov/fermi_lat_mon_trans.html using the BeautifulSoup library
• Convert the notice text into json example file, fermi_lat_example.json
• Generate the JSON schema as fermi_lat_schema.json using genson from the provided JSON example
• Validate the schema example against the JSON schema using Draft7Validator

Kafka notices

Typical Fermi LAT GCN notice contains the following information:

Properties	Type	Value
TITLE	string	GCN/FERMI NOTICE
NOTICE_DATE	string	Thu 23 Feb 23 15:49:32 UT
NOTICE_TYPE	string	Fermi-LAT Monitor
SOURCE_OBJ	string	BLLac_86400.png
REF_NUM	string	1677167372
RA	string	330.680d {+22h 02m 43s} (J2000),
DEC	string	+42.278d {+42d 16\' 40"} (J2000),
CURR_FLUX	string	1.70e-06 +- 6.50e-08 [ph/cm2/sec]
BASE_FLUX	string	6.99e-07 +- 1.59e-07 [ph/cm2/sec]
SIGNIFICANCE	string	5.59 [sigma]
TIME_SCALE	string	0 {0=1day, 1=1week}
ENERGY_BAND	string	0.1 - 300.0 [GeV]
OUTBURST_DATE	string	19997 TJD; 53 DOY; 23/02/22 (yy/mm/dd)
OUTBURST_TIME	string	43200.00 SOD {12:00:00.00} UT
SOLN_STATUS	string	0x0
LC_URL	string	http://fermi.gsfc.nasa.gov/FTP/glast/data/lat/catalogs/asp/current/lightcurves/BLLac_86400.png
SUN_POSTN	string	336.62d {+22h 26m 28s} -9.76d {-09d 45\' 42"}
SUN_DIST	string	52.41 [deg] Sun_angle= 0.4 [hr] (West of Sun)
MOON_POSTN	string	19.50d {+01h 17m 59s} +6.71d {+06d 42\' 18"}
MOON_ILLUM	string	15 [%]
GAL_COORDS	string	92.59,-10.44 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS	string	354.26, 49.58 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS	string	``