1. 800 years long journey explained. By: Bilal Karim Mughal

2. Tycho Brahe 14 Dec 1546 – 24 Oct 1601 Danish nobleman Known for accurate planetary observations Refuted Aristotle and Ptolemy’s theories about the Universe.

3. Tycho Brahe In November, 1572, Tycho Brahe observed the Supernova SN1572 Built an observatory “Uraniborg” in 1576

4. Tycho Brahe Presented Geo-Heliocentric explanation of the Solar System Prepared detailed star charts with accurate timings, without any telescope. Achieved supreme accuracy in predicting the positions of celestial bodies

5. Johannes Kepler Dec 27, 1571 – Nov 15, 1630 German Mathematician, Astronomer, and Astrologer Famous for his Laws of Planetary Motion.

6. Johannes Kepler Worked as Tycho Brahe’s assistant for 2 years Tycho did not trust Kepler, allowed him little access to his data Tycho Brahe asked him to develop an explanation of the Solar System

7. Johannes Kepler Tycho never believed the Planets to be orbiting the Sun. Kepler was unable to match this with Geometrical Models. Finally in 1609, Kepler gave Laws of Planetary Motion, describing that the Planets orbit the Sun.

8. The Question Was it purely the work of Tycho Brahe and Johannes Kepler that led to the current understanding of the Solar System?

9. Era of Muslim Scientists Spans over 600 years. Significant improvements in Geometry and Mathematics. Development of more sophisticated instruments like Sextant, Astrolabe.

10. Muhammad ibn Musa Al-Khwarizmi 780 – 850 C.E Mathematician, Astronomer, Geographer Developed the Tables for movements of Sun, Moon and 5 planets in 830. A.D

11. Muhammad Ibn Jabir Al Battani 858 – 929 C.E Determined the value of Solar day to be 365 days, 5 hours, 46 minutes and 24 seconds. Made significant advances in Trigonometry.

12. Abd al-Rehman Al Sufi December 7, 903 – May 25, 986 Wrote “The Book of Fixed Stars” in 964 Observed and described the Stars, their magnitudes, and their positions

13. Abu-Mahmud al-Khujandi 940 – 1000 C.E Persian Mathematician, Astronomer Accurately computed the tilt of the Earth’s axis to be (23.53°) in 994 A.D

14. Abu Rayhan Al-Biruni 973 – 1048 C.E Believed the Earth rotated about its own axis and around the Sun Wrote 35 treatises on Astronomy

15. Abu Rayhan Al-Biruni Calculated the circumference of Earth Believed in spherical Earth therefore Also discovered that gravity exists within the heavenly bodies

16. Ibn al-Haytham 965 – 1040 C.E Proposed the Earth's rotation on its axis in The Model of the Motions

17. Abu Said al-Sijzi 945 – 1020 C.E Persian Mathematician, Astronomer Suggested for the first time, the heliocentric system, in which Planets orbit the Sun Al-Biruni agreed with his ideas

18. Nasir al-Din al-Tusi 1201 – 1274 C.E Built an observatory at Maragha Made accurate tables of planetary motions Calculated the Precession of Equinoxes

19. Mirza Muhammad Tariq Ulugh Beg 1394 – 1449 C.E In 1424 built an observatory at Samarkand Found the values of trigonometric tables up to 8 decimal places Determined the Earth’s axial tilt to be 23.52 degrees

20. Mirza Muhammad Tariq Ulugh Beg Calculated the value of Sidereal year to be 365d, 6h, 10m, 8s (only 62 seconds more than the present estimation)

21. Taqi al-Din Muhammad ibn Ma'ruf 1526 – 1585 C.E Built an observatory at Istanbul Wrote 33 treatises on Astronomy

22. Taqi al-Din Muhammad ibn Ma'ruf Paved the way for the transfer of Islamic knowledge to the West Developed an Astronomical Catalogue more accurate than Nicolaus Copernicus and Tycho Brahe Final astronomer of Muslim Era

23. Conclusion Tycho Brahe was the champion in observations Kepler was successful in presenting the true image of Solar System But the real pioneers of it were Muslim scientists of Medieval times who had researched for more than 400 years and had founded the base for Tycho Brahe and Johannes Kepler

24. References Dictionary of Scientific Biography (1970) Encyclopedia of the History of Arabic Science by Regis Morelon and Rushdi Rashed The Touch of Midas: Science, Values and Environment in Islam and the West by M.A Kettani Astronomy and Mathematics by Carra de Vaux