Sideric means “stellar”.

True Sidereal Astrology is based on the actual, astronomically observable constellations in the sky as they truly exist—meaning that it does not simply assign 30° to each sign, but instead uses the exact size of each constellation, which varies because the constellations differ in their length in relation to the ecliptic.

Here is a list of how the Sun moves along the ecliptic through the zodiac signs, adjusted for the year 2026:

• Aries 22.4.- 12.5.

• Taurus 12.5.- 19.6.

• Gemini 20.6.- 20.7.

• Cancer 21.7.- 7.8.

• Leo 8.8.- 15.9.

• Virgo 16.9.- 5.11.

• Libra 6.11.- 23.11.

• Scorpio 24.11.- 6.12.

• Ophiuchus 7.12.- 19.12

• Sagittarius 20.12.- 20.1.

• Capricorn 21.1- 15.2.

• Aquarius 16.2. -10.3.

• Pisces 11.3.- 21.4.
  
  The colors are adapted to Truesky's horoscope display
  (as you can see, the zodiac sign columns are different sizes):

Frequently asked questions

What is different from Western Astrology?

The constellations in the sky no longer correlate with the Western Zodiac Signs, as these were fixed to days and seasons rather than the actual constellations.

For example, the Western Zodiac begins with the equinox in March with the sun in Aries. In the actual sky, however, the sun is still in the zodiac sign of Pisces.

The Western Zodiac describes symbolic cycles, and True Sidereal Astrology shows the visible sky.

Is there an online calculator?

No, because in True Sidereal Astrology one works with the actual lengths of the zodiac signs along the ecliptic, while in Vedic Astrology one works with equal 30° signs. Furthermore, in Vedic Astrology one uses a completely different house system.

Why do so few people know about it?

As in Western Astrology, I use the Placidus House System, so the positions of the celestial bodies in relation to each other and in relation to the houses are identical to those in Western Astrology.
Therefore there are many similarities, for example, the positions of the planets in relation to each other and the position of the planets in the houses.

More and more people have at least heard of it.
However, many people identify strongly with a few signs in their horoscope, making it very difficult to change their minds, especially if they have been involved with Western Astrology for a long time.

Which house system do I use?

Who wants to hold on to their “old” zodiac sign?

The most difficult thing for people born between January 21 and February 15 is the “transition” from Aquarius to Capricorn. Some also find it very difficult to let go of Sagittarius or Scorpio.

What is the 13th sign of the zodiac?

The Snakecarrier, Ophiuchus, is the 13th sign of the zodiac, which has been omitted in Western, Vedic, and Sidereal Astrology. The sun passes through it between December 7 and 19, and it is a hybrid of water and fire, death and rebirth.

Yes, fortunately there is now a dedicated online website that I can recommend for creating True Sidereal horoscopes.
Make an account and dont forget to switch from „Tropical“ to „Midpoint Sidereal“.
https://truesky.masteringthezodiac.com/

Is Sidereal Astrology equal to Vedic Astrology?