Humans have been watching the night sky for thousands of years.  The ancient Babylonians developed astrology and identified the 12 signs of the Zodiac.  The Greeks inherited this knowledge and developed it further, and the Arabs built upon the Greek system and added what they learned from the Indians.  Astrology is the belief that the planets and stars affect the lives of people here on earth.  Most ancient cultures believed in this, and so they watched the stars very carefully in order to try and predict the future.  From this belief in astrology arose the science of astronomy.

Ptolemy - famous Greek astronomer and mathemetician, who lived in Alexandria, Egypt, in the 2nd century A.D. He developed what became known as the Ptolemaic System of astronomy, in which the stars and planets revolve around the earth.  He catalogued over 1000 stars and their measurements.

Bayt al-ikmah - "The House of Wisdom."   Institution founded by the Khalifah (Caliph) al-Ma'muun in the year 830 to translate scientific texts from Greek, Syriac, Persian and other languages into Arabic.

Muslims built first observatory as scientific institution in 13th century at Maraghah in Iran.  Back then there were no telescopes and star observations were made with the human eye alone.  Precise measurement of the stars could be used for navigation on land and sea.  The Arabs not only developed the observatories, but also the instruments to observe and measure the stars and planets.

One of the most important inventions was the astrolabe:  it was first developed by the Greeks, but the Arabs perfected it.  By calculating the positions of the stars, the astrolabe could tell you what direction you were going, what direction to pray in toward Mecca etc.  The astrolabe was used for some 1000 years in Europe and the Arab world for navigation at sea and on land.

Some famous Arab and Iranian astronomers, scientists and mathematicians
There are many others, but here are a few of the most famous.  Some are known in the West by their Latinized names, because their works were translated into Latin.  The translation of Arabic scientific texts, and the introduction of Arabic numerals into Europe, are some of the most important factors which sparked the European Renaissance.

Al-Khwarizmi, d. 849  Invented Algebra as we know it, based on mathematical works of the Greeks and Indians.  "Algorithm" and "Algorism" are two English math words that come from his name.

Al-Farghani (Alfraganus), d.850, wrote the Elements, a summary of Ptolemaic astronomy studied in Europe until 1600.

Al-Battani (Albategnius), d. 929   Arab astronomer and mathematician, well known throughout Europe. He corrected some of Ptolemy's observations. His most famous work is "On Stellar Motion."

Ibn al-Haytham (Alhazen), d. 1038  Astronomer and physicist.  He wrote the Optical Thesaurus, the first important work on dioptrics (the optics of the eyes), which influenced the work of Roger Bacon, the 13th century English scholar.

^cUmar Khayyam, d. 1123  Known mostly as a Persian poet, he became famous in the West when his book of poems The Rubaiyat were translated into English.  However, he was also a famous philosopher, mathematician and astronomer.  He
made important developments in geometry and corrected the calendar which was being used at that time.
 
Ibn Sina (Avicenna), d.1037  Probably the most famous Arab scientist of them all.   He wrote on astronomy, physics, and medicine, which he also practiced, and his great medical textbook was taught in Europe for  700 years.

Al-Biruni,  d.1048, one of the greatest Arab encyclopedists of science.  He wrote books on mathematics, astronomy and astrology, geography, and history, and even botany.
 
Ibn Rushd (Averroes) d. 1198, Famous Arab scientist and philosopher, whose writings were very influential for hundreds
of years.  Among other things, he wrote important commentaries on Aristotle which were studied in Europe.
 

ENGLISH WORDS FROM ARABIC
Astronomy and Math

Algebra
Algorism
Algorithm
Almanac
Azimuth
Cipher
Nadir
Sine
Zenith
Zero

STAR NAMES FROM ARABIC

Many names of stars that we know are from Arabic--some of the biggest stars in the sky.    Some of them, having to do with the constellations, the Arabs translated from the Greek names.  But Europe got the names from the Arabs.

Aldebaran - the follower
Algol - the ghoul
Altair -  the flyer
Betelgeuse - in Orion - the house of Gemini
Deneb - tail (of the swan Cygnus)
Fomalhaut - mouth of the fish - Pisces
Hamal - lamb
Rigel - in Orion--the foot
Vega - The falling (eagle)

AL-ABRAAJ 
The Signs of the Zodiac

Burj - Astrological Sign or constellation (plural Abraaj)

Ma burjak?  What's your sign? (to a man)
Ma burjik?  What's your sign? (to a woman)
 
Aries - Al-amal - the Lamb (Ram)
Taurus - Ath-Thawr - the Bull
Gemini - Al-Jawzaa' or Al-Taw'amaan - the Twins
Cancer - As -Saraaan - the Crab
Leo - Al-Asad - the Lion
Virgo - Al-^cAthraa' - the Virgin (or as-Sunbulah - the Ear of Wheat)
Libra - Al-Miizaan - the Scales
Scorpio - Al-^cAqrab - the Scorpion
Sagittarius - Al-Qaws or ar-Raamii - the Archer
Capricorn - Al-Jadiy - the Goat
Aquarius - Ad-Dalw - the Water Pail
Pisces - As-Samakah or Al-uut - the Fish (or As-Samakataan - the Two Fishes)
 
For all sorts of information about astronomy and the Arab and Islamic study of astronomy, you can visit the web site of
the Jordanian Astronomical Society:   http://www.jas.org.jo/