Perspective: John Mather

Back Scientist's Perspective: John Mather
John Mather

Senior Project Scientist, JWST

Interview Date: Spring 2002

The James Webb Space Telescope will help us see the very first objects that formed after the Big Bang. Predictions say that we should be able to see clusters of the very first objects which are thought to be super-massive stars, that we call Population-3 stars, with a redshift of about 12 to 20. And there was possibly a second wave of star and galaxy formation with a redshift around seven to 11 that would have reionized the universe. So, we'll hope to see that these predictions are correct. We have the expectation of direct imaging of the very first ordinary galaxies. We don't know yet whether we should be able to see individual objects of the Population-3 type. Population-3 stars are expected to also explode as very luminous supernovae which could either lead directly to black holes or possibly just to ordinary, very metal-rich expulsions of gas into the inter-galactic medium. So, both are likely possibilities for us to attempt to see. Calculation says we should be able to see those giant supernovas.