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Sundial for 6:00 sidereal time

This is a horizontal sundial with hour lines for local apparent time.
Around the sundial is a date scale, showing the sum of the fixed longitude adjustment and the date-dependent equation of time. The numbers apply always to the first of the month.
This allows one to calculate civil time from the apparent time reading.
Another hour should be added for summer time (dst).
This elegantly shows the relation between solar and civil time.

Within the date scale there is another circular scale. This represents the ecliptic.
Also shown are the constellations in which the sun is on any given date.

The figure below names three constellations:
Leo, or Lion
Gemini, or Twins
Pisces, or Fish

Apparent time is the hour angle of the sun. At 12 hours LAT, the sun is due south.
Sidereal time is related to the position of the stars; it is the hour angle of the spring point: the First Point of Aries, or Vernal Equinox.

At 0:00 sidereal time, the spring point is due south.
The spring point is one of the two intersections between equator and ecliptic. It is where the sun is at the beginning of spring.

The sundial shows the position of the stars at 06:00 local sidereal time.
The summer point (1st of Cancer) is in the south, in the extension of the 12:00 hour line. The summer point lies between the constellations Gemini and Taurus (although it is in the sign of Cancer).
The spring point is now in the west, in the extension of the 18:00 hour line. The spring point lies between the constellations of Pisces and Aquarius (although in the sign of Aries).

When the shadow of the style on the outer edge indicates today’s date, it is 6:00 sidereal time, and therefore the actual positions of the constellations in the sky correspond to those indicated by the sundial.

Of course, the sun shines. It is therefore stargazing… by day!