Plans are now afoot to build a $500 million replacement called the Next Generation Space Telescope, which will be a 4-meter telescope designed to explore the 1 - 5 micron region, and to search for faint galaxies being born soon after the Big Bang. Because of the expansion redshift of the universe, to see galaxies like the Milky Way, you need to look at a wavelength in the near infrared where most of their star light has been redshifted. For more on the NGST, visit the NGST public site whose creation I am privileged to be working on these days!