... In front of a famous background of stars and galaxies lies some of Earth's more unusual trees. ... About 3 million years ago in the nearby galaxy M33, a large cloud of gas spawned dense internal knots which gravitationally collapsed to form stars. ... The Astronaut Who Captured a Satellite . ... In 1984, high above the Earth's surface, an astronaut captured a satellite. ... Earth at Night . ... No one is sure, but it is likely related to an active supermassive black hole at its center. ...