Oceans cover around 70 per cent of the Earth’s surface. As so much of the Earth’s surface is underwater, it is no surprise that marine species outnumber those on land. Actually 94 per cent of the living species exist within the oceans. As per the national ocean service, an office within the US department of commerce national oceanic and atmospheric administration, we have been able to explore less than five per cent of Earth’s oceans. In fact, Earth’s longest chain of mountains, the Mid-Ocean Ridge, is almost entirely beneath the ocean, stretching across a distance of 65,000 km. And we have explored Venus or Mars much more than this mountain chain.