HMI Ring Diagrams
Data Product Descriptions

sha.GONGsite_info

Description

This is a tiny data series containing the (supposedly) fixed geographical information associated with each of the six GONG sites. It can be referred to when detailed ephemeris information, specifically the components of the heliocentric observer velocity for a given site at a given time, are required. The series obviates the need for massive repetition of the keys in a series combining records from multiple sites. (For a series specific to a single site, they would be handled as constant keys.) There is of course no "image" SUMS data associated with the records to be archived.

The contents of the six records are:

# sha.GONGsite_info[BB]
SiteCode="BB"
Latitude=34.260330
Longitude=-116.921420
Elevation=2038.00
TimeZone=-480

# sha.GONGsite_info[CT]
SiteCode="CT"
Latitude=-30.167830
Longitude=-70.805470
Elevation=2230.00
TimeZone=-240

# sha.GONGsite_info[LE]
SiteCode="LE"
Latitude=-22.218499
Longitude=114.102721
Elevation=23.67
TimeZone=480

# sha.GONGsite_info[ML]
SiteCode="ML"
Latitude=19.536140
Longitude=-155.575920
Elevation=3441.33
TimeZone=-600

# sha.GONGsite_info[TD]
SiteCode="TD"
Latitude=28.300833
Longitude=-16.511944
Elevation=2478.00
TimeZone=0

# sha.GONGsite_info[UD]
SiteCode="UD"
Latitude=24.614940
Longitude=73.669690
Elevation=603.00
TimeZone=330

Note that in the original GONG site headers, the Latitude and Longitude are given in radians rather then degrees, expressed to a precision of 6 to 9 decimal digits depending on the processing version. This corresponds to a precision of between 6 m and 6 mm for latitude (or longitude at the equator). However, the reported values have occasionally changed considerably from time to time. For example the reported latitude of the Udaipur site has varied from 24.585 to 24.615 degrees, corresponding to a displacement of over 3 km. Likewise the reported elevations (which are undoubtedly of no importance for ephemeris determinations) have varied from 603 to 750 m for the Udaipur site and by 30 to 50 m for other sites. The adopted values correspond to those in headers from 2019.

JSOC Series Definition

#=====Global Series Information=====
Seriesname:	sha.GONGsite_info
Description:	"Location information for each GONG site"
Author:		"Rick Bogart"
Unitsize:	0
Archive:	0
Retention:	14610
Tapegroup:	0
PrimeKeys:	SiteCode

#=====Links=====

# ===== Keyword list ===== #
# Format:
#   Keyword: , link, , , 
# or
#   Keyword: , , {variable | variable}, {record | segment}, 
#            , , , 

# Prime keys
Keyword: SiteCode, string, variable, record, "", %s, N/A, "Site abbreviation"

# Variable keys
Keyword: Latitude, double, variable, record, NaN, %.6f, deg, "Geographic Latitude (north)"
Keyword: Longitude,double, variable, record, NaN, %.6f, deg, "Geographic Longitude (east)"
Keyword: Elevation,double, variable, record, NaN, %.2f, m, "Altitude"
Keyword: TimeZone, short,  variable, record, 0, %d, min, "Time Zone"

# Prime key slotting info (hidden)

#=====Segments=====

HMI Ring Diagrams

11 Feb 2024, 23:52-0800