The top satellite picture of Kalutara, Sri Lanka was taken about an hour after the first tsunami wave hit on December 26, 2004. Water is rushing back out to sea after inundating the land. The lower picture shows what the same area looks like under normal conditions. Click on image for full size (133 Kb) NASA

On the morning of December 26th, 2004, an enormous earthquake occurred below the Indian Ocean, 150 km west of an Indonesian island called Sumatra. The earthquake was caused by moving tectonic plates and was the most powerful to occur on our planet in the past 40 years. The earthquake caused part of the sea floor to rise about 10 meters. The seawater above was pushed up and formed huge tsunami waves that spread across the ocean.

The huge waves moved quickly across the ocean before hitting land. The waves caused a huge amount of destruction to towns and resorts along the coast. Over 150,000 people were killed as the tsunami waves hit the coasts of Indonesia, Malaysia, Myanmar, Thailand, Bangladesh, Sri Lanka, India, and the east coast of Africa. There was very little time to sound alarms and get people away from the coast.

The more you know about how the Earth works, the more you can keep yourself and others as safe as possible from natural disasters. We at Windows to the Universe would like to congratulate Tilly Smith, a 10-year-old British girl who used her knowledge about how tsunamis works to save 100 people during the event. Tilly learned about tsunamis at school two weeks before the tsunami hit where her family was vacationing in Phuket, Thailand. She saw the water drawing out quickly from the shore and remembered that this can happen before a tsunami wave hits the coast. Thanks to Tilly, her mother, and the hotel staff, everyone was cleared off the beach minutes before the wave arrived.