4500 BC Around this time, cultures like those in
Greece and
Rome began diving into the sea as a source of food gathering, commerce, and possibly even warfare.
1800 BC Basic measuring of the depths is done in Egypt.
1500 BC Middle Eastern peoples explored the Indian Ocean
600 BC
Phoenicians developed sea routes around the entire Mediterranean and into the
Red Sea and the
Indian Ocean. Going around
Africa they reached
England by sailing along the western European coast. Although they understood
celestial navigation, they probably stayed within sight of land whenever possible.
500-200 BC Greeks developed trade routes in the Mediterranean using the length of the day (corrected for the time of the year) to estimate
latitude.
450 BC
Herodotus publishes a map of the Mediterranean region.
325 BC
Pytheas, a Greek
astronomer and
geographer, sailed north out of the Mediterranean, reaching England and possibly even Iceland and Norway. He also developed the use of sightings on the
North Star to determine latitude.
150 AD
Ptolemy produces a map of the Roman world, including lines of
latitude and
longitude, the continents of
Asia, Europe, and Africa and the surrounding oceans.
1002 Leif Erikson reaches North America 500 years before Columbus.[2]
1405-1433 Chinese send
seven voyages to extend Chinese influence and impress their neighbor states. These expensive voyages are ended after a short time. See
Zheng He (1371–1433).
1698-1700
Edmund Halley made probably the first primarily scientific voyage to study the variation of the
magnetic compass, sailing as far as 52 deg S. in the
Atlantic Ocean. On a previous expedition to
St. Helena, he made an important contribution to knowledge of the trade winds.
1768-1780
James Cook explores the southern parts of the oceans looking for the southern continent. He was the first to use a
marine chronometer to determine longitude.
1872-1876
H.M.S. Challenger travels around the world on a scientific mission taking sediment samples, water samples, soundings, and collecting many biological specimens.
1960
Bathyscaphe Trieste dives to what was believed to be the deepest point in the
Mariana Trench. A depth of 10,915 meters was observed.
The renaissance of ocean exploration occurred in the 20th century, when
human-powered exploration became increasingly popular. Via this new medium, pioneering has once again become the goal of
ocean explorers.[3]