Deep mystery
Three years back, the Earth-orbiting Hubble Space Telescope aimed its Wide Field Planetary Camera 2 at what seemed to be an empty patch of sky, dubbed the Hubble Deep Field. The results revealed many far-off galaxies and strange, lumpy blue knots of light. Now, the spacecraft has reexamined the region using its Near-Infrared Camera and Multi-Object Spectrometer, which has a greater viewing range and shows many more distant galaxies, some of which are over 12 billion years old. The pictures reveal the blue clumps in the optical set to be areas of intense star formation within otherwise-ordinary galaxies.