Internal reference system
The internal cartesian reference system is a right-handed equatorial system with the particularity that the axes labels are unorthodox. Usually, points to the fundamental direction (
),
points “up” and
is the fundamental plane (
), with
.
In our case, it is which points to the fundamental direction (
),
points up and
is the fundamental plane (
), with
. In order to convert from common equatorial cartesian coordinates
to Gaia Sky coordinates
, you just need to swap the axes:
Or, what is the same, , and
.
Description
So, in Gaia Sky is the equatorial plane (
).
points towards the
vernal equinox point (
).
points towards the north celestial pole (
).
is perpendicular to both
and
and points to
so that
.
![Gaia Sky reference system](_images/refsys.png)
Gaia Sky reference system
All the positions and orientations of the entities in the scene are at some point converted to this reference system for representation. The same happens with the orientation sensor data in mobile devices.
Internal units
Internally, the objects in Gaia Sky are positioned using Internal Units.
The default Internal Units () are defined as follows:
When running in Virtual Reality mode, and only for the duration of the session, the Internal Units are scaled as follows: