Final selection of two projects for full funding will be based on data from the concept studies. Earth's day and night skies are lit with a bright infrared haze that makes it very difficult to see much of the infrared radiation coming from distant galaxies, just as sunlight makes it difficult to see most stars during the day. NGST's primary objective is to study the early universe, so it also will observe mainly in the infrared. From a perch beyond the orbit of the moon, NGST will be able to detect radiation from the distant universe with unprecedented sensitivity.
Astronomers can learn the most about the distant universe from rare and unusual objects.
NGST can give them a highly detailed look at those objects, but they've got to find the rare objects first, a job more suited to an instrument capable of surveying wider swaths of space in less detail. High redshift quasars, which emit incredible amounts of energy, are thought to be distant galaxies with supermassive black holes in their centers. The higher a quasar's redshift, the faster it is traveling away from Earth and the more distant it is. The current record for a quasar's redshift is 5.8. This prospect has astrophysicists like Zheng and Tsvetanov excited.