LOS ANGELES: Endlessly fascinated with the night sky, scientists are preparing to put a large, high-resolution infrared camera into orbit that will give a much clearer picture of what is in ''our solar neighbourhood''.

Because most telescopes plumb the heavens in visible light, vast landscapes of the cosmos are hidden from direct view. But the Wide-field Infrared Survey Explorer, or WISE, will photograph the entire night sky in infrared light. In the process, it will capture hundreds of thousands of previously unknown objects that are too cool and too dark to be seen.

The NASA Wide-field infrared Survey Explorer is shown inside one-half of the nose cone, or fairing, that will protect it during launch.

The expected launch of the $US320 million ($350 million spacecraft from Vandenberg Air Force Base in central California was delayed until Monday due to bad weather.

Once it is in orbit, scientists expect to find tens of thousands more asteroids between Mars and Jupiter; dozens of failed stars known as brown dwarfs; and possibly a giant planet beyond Pluto. Scientists say WISE could revise the familiar portrait of our solar system.