edited by H Gursky (Naval Research Laboratory, USA), R Ruffini (University of Roma La Sapienza, Italy), & L Stella (Osservatorio Astronomico di Roma, Italy)

This volume is dedicated to Riccardo Giacconi for his sixty-fifth birthday, on the occasion of his being awarded a “Laurea Honoris Causa” in physics at the University of Rome “La Sapienza”. A meeting was held in his honor, and presentations were given that reflected the state-of-the-art of research on subjects related to Giacconi's scientific interests and achievements through the decades. This volume is based upon the papers presented at that meeting. It provides a tribute to Riccardo Giacconi for his outstanding contributions towards opening up the entire field of high energy astrophysics.

• X-Ray Astronomy: The First Decade (H Gursky)
• X-Ray Astronomy from Uhuru to Einstein (W H Tucker & H Tananbaum)
• Historical Development of X-Ray Optics for Astronomy (L P van Speybroeck)
• The Divergent Evolution of the X-Ray Telescope (P Gorenstein)
• From Starfish to EXOSAT — My Various Interactions with Riccardo Giacconi (K A Pounds)
• X-Ray Astronomical Spectroscopy (S Holt)
• The X-Ray Background and the ROSAT Deep Surveys (G Hasinger & G Zamorani)
• Musings About X-Ray Luminosity Functions and Source Counts (M Schmidt)
• The Brightest Extragalactic Radio Sources in the Sky as Observed at Radio, HST and X-Ray Wavelengths (M S Longair)
• Clusters of Galaxies in X-Rays (A Cavaliere)
• Hot Gas and Dark Matter in Galaxies and Clusters (W Forman & C Jones)
• Clusters of Galaxies: A Commentary (G Chincarini)
• Evolution of the Abundance of X-Ray Galaxy Clusters Out to z ~ 1 (P Rosati)
• Life and Times of the X-Ray Gas in Elliptical Galacies (A Renzini)
• The Beginnings of Stellar X-Ray Astronomy (R Rosner)
• Stellar Cornal Structures (S Serio)
• Understanding X-Ray Stars: The Discovery of Binary X-Ray Sources (E J Schreier & H Tananbaum)
• X-Ray Emission from Neutron Stars — Some Personal Reflections and Recent Developments (J Trümper)
• X-Ray Imaging of Crowded Fields and Grain Scattered Halos (G W Clark & J W Woo)
• Iron Kα-Line Emission from Neural Interstellar Gas (R Sunyaev)
• General Relativity with Quasi-Periodic Oscillations from Low Mass X-Ray Binaries (L Stella)
• Lessons from X-Ray Astronomy Applied to HST (E J Schreier & R Doxsey)
• HST Observations of Extragalactic Optical Jets (F D Macchetto)
• High Redshift Radio Galaxies: From HST to VLT — A Proto-Cluster at z=2.2? (G Miley et al.)
• Probing the Cosmic “Dark Age” with the VLT (M J Rees)
• On the Critical Mass (R Ruffini)