The James Webb Space Telescope (JWST) is a large, infrared space telescope that has recently started its science program which will enable breakthroughs in astrophysics and planetary science. Notably, JWST will provide the very first observations of the earliest luminous objects in the universe and start a new era of exoplanet atmospheric characterization. This transformative science is enabled by a 6.6 m telescope that is passively cooled with a 5 layer sunshield. The primary mirror is comprised of 18 controllable, low areal density hexagonal segments, that were aligned and phased relative to each other in orbit using innovative image-based wave front sensing and control algorithms. This revolutionary telescope took more than two decades to develop with a widely distributed team across engineering disciplines. We present an overview of the telescope requirements, architecture, development, superb on-orbit performance, and lessons learned. JWST successfully demonstrates a segmented aperture space telescope and establishes a path to building even larger space telescopes.

X-ray diffraction from piezoelectrically amplified acoustic shear waves in GaAs is reported. The spectrum of amplified acoustic flux is obtained in the microscopic limit, where the electron mean free path is much greater than the acoustic wavelength. The peak acoustic intensity occurs at 50 GHz, which corresponds to the frequency of maximum net gain according to the linear theory. The spectrum of piezoelectrically amplified acoustic waves is observed at frequencies an order of magnitude larger than may be studied by the previously reported Brillouin scattering technique.

The Video Guidance Sensor is a key element of an automatic rendezvous and docking program administered by NASA. The system uses laser illumination of a passive target in the field of view of an on-board camera and processes the video image to determine the relative position and attitude between the target and the sensor. Theoretical predictions and evaluations, and laboratory measurements and tests are presented for the lasers, target components, camera system, signal processor, and a solar simulator.

The James Webb Space Telescope (JWST) is a large, infrared space telescope that has recently started its science program which will enable breakthroughs in astrophysics and planetary science. Notably, JWST will provide the very first observations of the earliest luminous objects in the Universe and start a new era of exoplanet atmospheric characterization. This transformative science is enabled by a 6.6 m telescope that is passively cooled with a 5-layer sunshield. The primary mirror is comprised of 18 controllable, low areal density hexagonal segments, that were aligned and phased relative to each other in orbit using innovative image-based wavefront sensing and control algorithms. This revolutionary telescope took more than two decades to develop with a widely distributed team across engineering disciplines. We present an overview

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