From ancient times, astrology developed as early scientists followed planets moving across the sky, with the fixed stars and constellations as a reference point. All of it was visible to the human eye.
The ancient vedic system of astrology, still in use today, is faithful to its origins. This includes the use of the seven visible planetary bodies and the visible sidereal zodiac.
Most of the astrology practiced in the western world in modern times, however, has developed with recourse to invisible phenomena. The tropical zodiac was identical to the sidereal zodiac in 200 A.D.. Since then, the tropical zodiac has drifted by 25° (23° 51' in terms of the traditional Lahiri ayanamsa) with reference to the Vernal Point of the sideral zodiac (at 5° Pisces in 2000 A.D.) and the fixed stars. It has moved 1° per 72 years due to the precession of the equinoxes and is now 25° removed from the visible zodiac. Moreover, 360 years from now (5° x 72 years) , the tropical zodiac will have moved a whole sign, or 30°, from its placement in 200 A.D. Indeed, 2,190 years later the sidereal zodiac will still be seen to be in the same heavenly location, marked by the constellations that make up the sign Aries. However, by then the Sun's entry into the sign Aries, will take place a month later in the year for vedic or sidereal astrologers. As an example, the Sun entered 0° Aries on March 20, in 200 A.D. with both the tropical and sidereal zodiacs aligned. The Sun will again enter Aries in the sidereal zodiac on April 20 of 2,390 A.D. However, for the tropical zodiac, on March 20, 2,390 A.D. the Sun will be seen by western or tropical astrologers to enter constellations that make up the sign Pisces, but it will then be known as the sign Aries.
The ancient vedic astrology is not only based on the visual zodiac in the sky but it also only uses the visible planetary bodies in the sky. Indeed, aside from the Sun which rules over the sky in daytime, it is only the Moon, Venus, Mercury, Mars, Jupiter and Saturn which are visible in the sky at night. In addition, Vedic astrology also uses the calculated astronomical points in the Moon's orbit around the Earth, the Moon's nodes, Rahu and Ketu. This is because the lunar nodes are important to time solar and lunar eclipses, as explained in the article The truth about eclipses. Aside from that, Vedic astrology does not use the invisible zodiac or the invisble and distant planets of Uranus and Neptune. Nor does it use the very distant, tiny and invisible bodies of e.g. Pluto, Sedna, Eris, etc. These more distant astronomical bodies were discovered in more recent times with advances in telescopy. The influence of the invisible and distant bodies on terrestrial life is much more controversial than that of the closer and visible bodies, notably the Moon. Vedic astrology is focused on the visible and fundamental elements and is accordingly known as the Science of Light.
There are many amazing information resources on the internet. In the domain of astrology, the web site of Indian astrologer V.K. Choudhry, creator of the Systems' Approach, is one such resource. It offers information about how to correctly interpret horoscopes and make repeat accurate predictions. Importantly, the Systems’ Approach astrology (SA) is based on the ancient vedic astrology of the visible planets and sidereal zodiac.