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.

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Orbital spacecrafts face the problem of high thermal gradients or different thermal loads mediated by differential illumination from the sun. As spacecrafts are limited in weight there is a growing interest in heat transfer solutions, which are lightweight and economical. Variable electrochromic radiation heat transfer is a promising approach as it offers a better mass budget by saving heater power in the coldest boundary conditions. The focus of the present work is on the engineering and the material science of such electrochromic radiators, which are based on electrochemical cells and the intercalation of Li +-Ions into transition-metal-oxides. Samples out of soda lime glass, Kapton and high thermal conductive pyrolytic graphite foil, with different absorption modulation, are prepared by the use of reactive magnetron sputtering and electrochemical intercalation. The purpose of this work is represented by maximizing the Δα and Δε, feasibility of oppositional α/ε modulation, different substrate testing and relate the results with preliminary on-orbit simulations. Several concepts of electrochromic radiators are investigated in the last years. They are made out of full solid state materials or implemented with electrolyte-polymers and a Δε up to 0.5 and still high absorptivity. We found a modulation range of-0.14 up to 0.23 for the infrared emissivity and 0.43 up to 0.58 for transmittance in the spectral range of 300 to 1000 nm in the case of single layers. Aluminized Kapton shows twice as high absorption modifications as aluminized graphite foil, which is caused by the intercalation of Li + in the graphite-structure instead of tungsten oxide. The modulation is not yet sufficient in range and it's oppositional α/ε. The pyrolytic graphite foils are not suitable for direct deposition of the electrochromic stack and should be used for thermal distribution only. According to the experimental data, a simple stack with a Δε in the range of 0.21 to 0.29 seems to be realizable.

: The HADES Europa mission concept aims to provide a framework for an astrobiological in-depth investigation of the Jupiter moon Europa, relying on existing technologies and feasibility. This mission study proposes a system consisting of an orbiter, lander and cryobot as a platform for detailed exploration of Europa. While the orbiter will investigate the presence of a liquid ocean and characterize Europa's internal structure, the lander will survey local dynamics of the ice layer and the surface environment. The lander releases a cryobot, that melts into the ice, will sample the pristine subsurface and is expected to provide data on organic and gaseous content and putative bio-signatures. In summary, we present the scientific objectives for an astrobiological investigation of Europa, resulting in a mission concept with a detailed evaluation of scientific instrumentation, mission sequences, basic design of the spacecraft, technology needs and cost estimations.

The Near-Infrared Spectrograph (NIRSpec) is one of the four focal plane instruments on the James Webb Space Telescope which was launched on Dec. 25, 2021. We present an overview of the as-run NIRSpec commissioning campaign, with particular emphasis on the sequence of activities that led to the verification of all hardware components of NIRSpec. We also discuss the mechanical, thermal, and operational performance of NIRSpec, as well as the readiness of all NIRSpec observing modes for use in the upcoming JWST science program.