A SpaceX Falcon 9 launch using a booster that has now flown three dozen times created a “space jellyfish” effect in the ...

Now is the time to look for noctilucent clouds — shimmering ice clouds that glow near the edge of space.

It takes just minutes for the earth to swallow me whole as I abseil into the cave’s mouth. My feet bounce off rock until suddenly the wall slopes away into a yawning cavern and I’m kicking out at open ...