️<unk>️<unk>️<unk>️  ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️ Scientists have provided the best estimates yet, claiming it once had more water than the Arctic Ocean - and the planet kept these oceans for more than 1.5 billion years.<unk> Scientists have provided the best estimates yet, claiming it once had more water than the Arctic Ocean - and the planet kept these oceans for more than 1.5 billion years. ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️ NASA scientists in Maryland have calculated how much water was once on Mars.<unk> NASA scientists in Maryland have calculated how much water was once on Mars.<unk> NASA scientists in Maryland have calculated how much water was once on Mars. They found that 3.7 billion years ago it had more than the Arctic Ocean.<unk> They found that 3.7 billion years ago it had more than the Arctic Ocean. Most of this would have been in the northern hemisphere of the planet (illustrated).<unk> Most of this would have been in the northern hemisphere of the planet (illustrated). <unk> <unk> <unk> ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️ During its wet Noachian period - 4.1 to 3.7 billion years ago - it is estimated that it had enough water to cover the entire surface in a liquid layer 450 feet (137 meters) deep.<unk> During its wet Noachian period - 4.1 to 3.7 billion years ago - it is estimated that it had enough water to cover the entire surface in a liquid layer 450 feet (137 meters) deep. ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️ ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️ Microsoft's <unk>HoloLens' headset, which allows wearers to see 3D images superimposed over their vision, may look like it belongs in a sci-fi film. <unk> Microsoft's <unk>HoloLens' headset, which allows wearers to see 3D images superimposed over their vision, may look like it belongs in a sci-fi film. <unk> <unk> <unk> <unk> <unk> <unk> <unk> <unk> <unk> <unk> <unk> <unk> ️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️<unk>️ ••••••••••••••
NASA Goddard scientists in Maryland studied past water on Mars <unk> NASA Goddard scientists in Maryland studied past water on Mars <unk> They found that 3.7 billion years ago it had more than the Arctic Ocean. Most of this would have been in the northern hemisphere of the planet.<unk> Most of this would have been in the northern hemisphere of the planet.<unk> Since then, 87% has been lost to space and the rest is in ice at the poles.<unk> Since then, 87% has been lost to space and the rest is in ice at the poles. <unk> <unk> <unk> <unk> <unk> <unk> <unk> <unk> <unk> This is longer than the period of time needed for life to develop on Earth<unk>