This nebula was discovered in 1747 by Le Gentil, but the open cluster of NGC 6530 was discovered the previous century by John Flamsteed.
HOW TO FIND IT:
With M8, we are going to be moving along a chain of nebulae and clusters.
On a clear, dark night, M8 should be visible with the unaided eye. It is a hazy patch in the cloud-like Milky Way.
Draw a line from Eta Scorpii through Lamda Scorpii, extending the line about twice that distance.
WHAT TO LOOK FOR:
The observer will find this object by looking for what will appear to look like a pair of nebulae. A dark lane cuts across this nebula, giving M8 its nickname as the Lagoon Nebula.
You will see an open cluster of stars (NGC 6530) in the same view.
M8 is one of the best nebulae in the heavens.