Google on Monday launched the latest version of Google Earth with new features that enable users to dive into the ocean, travel back in time and visit Mars.

The ocean feature of Google Earth 5.0 provides users the opportunity to navigate beneath the ocean surface, explore 3D sea floor terrain and visit some of the most difficult-to-reach parts of the world.

Google expects the new feature to help change users' view about the ocean and related environmental issues.

"In discussions about climate change, the world's oceans are often overlooked despite being an integral part of the issue," Eric Schmidt, Google's chief executive officer, said in a statement.

"About one-third of the carbon dioxide that we emit into the atmosphere ends up in the oceans. Furthermore, biodiversity loss in our oceans in the next 20-30 years will be roughly equivalent to losing an entire Amazon rainforest, but this goes unnoticed because we can't see it," he added.

The new version of Google Earth also introduces Historical Imagery, a feature that allows users to observe a single location' s development over time through archival satellite and aerial imagery.

Another feature is Google Mars 3D, which uses high resolution imagery and 3D terrain of Mars to guides users to take a virtual tour of the planet.

Google Earth is a computer program that combines satellite imagery, maps and other geographic information to help users virtually view locations around the globe.

Since its launch in June 2005, Google Earth has been downloaded more than 500 million times.

(Xinhua News Agency February 3, 2009)