This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.

The Near Infrared Camera (NIRCam) is one of the four science instruments of the James Webb Space Telescope (JWST). Its high sensitivity, high spatial resolution images over the 0.6 − 5 μm wavelength region will be essential for making significant findings in many science areas as well as for aligning the JWST primary mirror segments and telescope. The NIRCam engineering test unit was recently assembled and has undergone successful cryogenic testing. The NIRCam collimator and camera optics and their mountings are also progressing, with a brass-board system demonstrating relatively low wavefront error across a wide field of view. The flight model's long-wavelength Si grisms have been fabricated, and its coronagraph masks are now being made. Both the short (0.6 − 2.3 μm) and long (2.4 − 5.0 μm) wavelength flight detectors show good performance and are undergoing final assembly and testing. The flight model subsystems should all be completed later this year through early 2011, and NIRCam will be cryogenically tested in the first half of 2011 before delivery to the JWST integrated science instrument module (ISIM).

This paper is the third in the series on the technology development for the EXCEDE (EXoplanetary Circumstellar Environments and Disk Explorer) mission concept, which in 2011 was selected by NASA's Explorer program for technology development (Category III). EXCEDE is a 0.7m space telescope concept designed to achieve raw contrasts of 1e6 at an inner working angle of 1.2 l/D and 1e7 at 2 l/D and beyond. This will allow it to directly detect and spatially resolve low surface brightness circumstellar debris disks as well as image giant planets as close as in the habitable zones of their host stars. In addition to doing fundamental science on debris disks, EXCEDE will also serve as a technological and scientific precursor for any future exo-Earth imaging mission. EXCEDE uses a Starlight Suppression System (SSS) based on the PIAA coronagraph, enabling aggressive performance.Previously, we reported on the achievement of our first milestone (demonstration of EXCEDE IWA and contrast in monochromatic light) in air. In this paper, we report on our continuing progress of developing the SSS for EXCEDE, and in particular (a) the reconfiguration of our system into a more flight-like layout, with an upstream deformable mirror and an inverse PIAA system, as well as a LOWFS, and (b) testing this system in a vacuum chamber, including IWA, contrast, and stability performance. The results achieved so far are 2.9e-7 contrast between 1.2-2.0 l/D and 9.7e-8 contrast between 2.0-6.0 l/D in monochromatic light; as well as 1.4e-6 between 2.0-6.0 l/D in a 10% band, all with a PIAA coronagraph operating at an inner working angle of 1.2 l/D. This constitutes better contrast than EXCEDE requirements (in those regions) in monochromatic light, and progress towards requirements in broadband light. Even though this technology development is primarily targeted towards EXCEDE, it is also germane to any exoplanet direct imaging space-based telescopes because of the many challenges common to different coronagraph architectures and mission requirements.

The science capabilities and features of an innovative and revolutionary approach to remote sensing imaging systems aimed at increasing the return on future planetary science missions many fold are described. Our concept, called Multiple Instrument Distributed Aperture Sensor (MIDAS), provides a large-aperture, wide-field, diffraction-limited telescope at a fraction of the cost, mass and volume of conventional space telescopes, by integrating advanced optical imaging interferometer technologies into a multi-functional remote sensing science payload. MIDAS acts as a single front-end actively controlled telescope array for use on common missions, reducing the cost, resources, complexity, and risks of developing a set of back-end science instruments (SIs) tailored to each specific mission. By interfacing to multiple science instruments, MIDAS enables either sequential or concurrent SI operations in all functional modes. Passive imaging modes enable remote sensing at diffraction-limited resolution sequentially by each SI, as well as at somewhat lower resolution by multiple SIs acting concurrently on the image, such as in different wavebands. MIDAS inherently provides nanometer-resolution hyperspectral passive imaging without the need for any moving parts in the SI's. Our optical design features high-resolution imaging for long dwell times at high altitudes, <1m GSD from the 5000km extent of spiral orbits, thereby enabling regional remote sensing of dynamic planet surface processes, as well as ultra-high resolution of 2cm GSD from a 100km science orbit that enable orbital searches for signs of life processes on the planet surface. In its active remote sensing modes, using an integrated solid-state laser source, MIDAS enables LIDAR, vibrometry, surface illumination, ablation, laser spectroscopy and optical laser communications. The powerful combination of MIDAS passive and active modes, each with sequential or concurrent SI operations, increases potential science return for space science missions many fold. For example, on a mission to the icy moons of Jupiter, MIDAS enhances detailed imaging of the geology and glaciology of the surface, determining the geochemistry of surface materials, and conducting seismic and tidal studies.

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