Table 1: A complete list of all coordinate parameters referred to in this document. Also included is the associated WCS label where appropriate, and the units in which the parameters are expressed. Parameters given in meters can also be expressed as relative to the solar radius $R_\odot$ .
Par Units WCS label Description

t - Observation date/time

$R_\odot$ m Solar radius ( ${\approx}6.96 \times 10^{8}$ m)

$D_\odot$ m DSUN Distance between the observer and Sun center

$\Theta$ deg HGLT Heliographic latitude

CRLT Synonym when used with CRLN

$\Phi$ deg HGLN Stonyhurst heliographic longitude

$\Phi\mbox{$_{\mbox{\tiny C}}$ }$ deg CRLN Carrington heliographic longitude

L₀ deg Carrington longitude of central meridian as seen from Earth

r m HECR Radial distance from sun center

h m HECH Radial distance from the solar surface, $h=r-R_\odot$

x m SOLX Heliocentric westward distance

y m SOLY Heliocentric northward distance

z m SOLZ Heliocentric observerward distance

$\rho$ m SOLI Heliocentric impact parameter

$\psi$ deg HCPA Position angle from solar North

HRLN Synonym when used with HRLT

$\theta_x$ deg HPLN Helioprojective westward angle

$\theta_y$ deg HPLT Helioprojective northward angle

$\theta_\rho$ deg Helioprojective impact angle

$\delta_\rho$ deg HRLT Helioprojective-radial declination angle, defined as $\theta_\rho - 90\hbox{$^\circ$ }$

d m DIST Radial distance from the observer

$\zeta$ m HPRZ Helioprojective analog of z, defined as $D_\odot - d$

$\mu$ - Cosine of the angle to the surface normal

B₀ deg Tilt of the solar North rotational axis toward the observer (heliographic latitude of the observer)

$\Phi_0$ deg Stonyhurst heliographic longitude of the observer

**Table 1:** A complete list of all coordinate parameters referred to in this document. Also included is the associated WCS label where appropriate, and the units in which the parameters are expressed. Parameters given in meters can also be expressed as relative to the solar radius $R_\odot$ .
Par	Units	WCS label	Description
t	-		Observation date/time
$R_\odot$	m		Solar radius ( ${\approx}6.96 \times 10^{8}$ m)
$D_\odot$	m	`DSUN`	Distance between the observer and Sun center
$\Theta$	deg	`HGLT`	Heliographic latitude
		`CRLT`	Synonym when used with `CRLN`
$\Phi$	deg	`HGLN`	Stonyhurst heliographic longitude
$\Phi\mbox{$_{\mbox{\tiny C}}$ }$	deg	`CRLN`	Carrington heliographic longitude
L₀	deg		Carrington longitude of central meridian as seen from Earth
r	m	`HECR`	Radial distance from sun center
h	m	`HECH`	Radial distance from the solar surface, $h=r-R_\odot$
x	m	`SOLX`	Heliocentric westward distance
y	m	`SOLY`	Heliocentric northward distance
z	m	`SOLZ`	Heliocentric observerward distance
$\rho$	m	`SOLI`	Heliocentric impact parameter
$\psi$	deg	`HCPA`	Position angle from solar North
		`HRLN`	Synonym when used with `HRLT`
$\theta_x$	deg	`HPLN`	Helioprojective westward angle
$\theta_y$	deg	`HPLT`	Helioprojective northward angle
$\theta_\rho$	deg		Helioprojective impact angle
$\delta_\rho$	deg	`HRLT`	Helioprojective-radial declination angle, defined as $\theta_\rho - 90\hbox{$^\circ$ }$
d	m	`DIST`	Radial distance from the observer
$\zeta$	m	`HPRZ`	Helioprojective analog of z, defined as $D_\odot - d$
$\mu$	-		Cosine of the angle to the surface normal
B₀	deg		Tilt of the solar North rotational axis toward the observer (heliographic latitude of the observer)
$\Phi_0$	deg		Stonyhurst heliographic longitude of the observer

Source LaTeX | All tables | In the text