Recent advances in astronomy have enabled scientists to reach the early universe to an unprecedented depth. With the new telescopes such as the Chandra, FUSE, and with the Sloan Digital Sky Survey (SDSS), we have gained critical insights into the “Origin of our Universe”, i.e. how the intergalactic medium evolves to form galaxies and quasars. SDSS has broken a ten-year barrier of z = 5 to reach the very early universe, with the discovery of five quasars at z ≥ 5. 0. The survey will find more than ten thousands of quasars, enabling us to carry out the most comprehensive classification of quasars. FUSE finds traces of the primordial matter at z ～ 3, which corresponds to hydrogen column density as low as 10-11 cm-2 and cannot be detected even with the largest optical telescope. The finding suggests that the intergalactic medium is an evolving and complex entity, and it is ionized mainly by the accumulated radiation from quasars. The Chandra telescope has taken a million second deep exposure of a selected region,reaching about twenty times deeper than ROSAT to a limiting flux of 5 × 1 0-17 ergs s-1 cm-2 in the 0. 5-2 keV band. The sources found so far can account for up to 90 % of the hard X-ray background field, and they consist of Seyfert-2 and normal galaxies at z ＜ 1 and quasars at z ＜ 4.5. In the near future, the Next Generation Space Telescope and others will reveal the first generation of baryonic objects after the Big Bang.
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