Satellite images beamed down from outer space have given scientists unprecedented insights into our natural world and the ability to help protect it.
We’ve learnt a lot of things by looking out into space; how stars work, how black holes are formed, how light travels through the Universe. But we can also learn more about our world by looking at Earth from space. Satellite images beamed down from outer space have given scientists unprecedented insights into our natural world and the ability to help protect it.
In the offshore coral reefs that surround many island nations, patterns have been forming. Within the reefs, scores of tiny fish call these coral paradises home. Using the coral structures as protection from larger predators, they often venture to just beyond the reef in search of food - knowing they can quickly swim back to safety. As they feast on the food sources around the coral, they leave behind the sand beneath. These sandy rings around the coral are visible from space - known to scientists as a 'grazing halo'. More than just a patch of empty sand, these halos keep scientists informed about the health of our marine ecosystems. If the rings of sand get too big around the coral it shows that the number of predators has declined, allowing more and more of the smaller fish to safely venture out for food at greater distances. If the grazing halos are too small, or non-existent, it means that there are too many predators and the smaller fish cannot leave the coral to feed. A good-sized halo means the marine environment is in its natural balance.