The European Space Agency's Planck satellite, launched on 14 May 2009, is the third-generation space experiment in the field of cosmic microwave background (CMB) research. It will image the anisotropies of the CMB over the whole sky, with unprecedented sensitivity ( ΔT T ∼ 2 × 10 −6 ) and angular resolution (∼5 arcmin). Planck will provide a major source of information relevant to many fundamental cosmological problems and will test current theories of the early evolution of the Universe and the origin of structure. It will also address a wide range of areas of astrophysical research related to the Milky Way as well as external galaxies and clusters of galaxies. The ability of Planck to measure polarization across a wide frequency range (30−350 GHz), with high precision and accuracy, and over the whole sky, will provide unique insight, not only into specific cosmological questions, but also into the properties of the interstellar medium. This paper is part of a series which describes the technical capabilities of the Planck scientific payload. It is based on the knowledge gathered during the on-ground calibration campaigns of the major subsystems, principally its telescope and its two scientific instruments, and of tests at fully integrated satellite level. It represents the best estimate before launch of the technical performance that the satellite and its payload will achieve in flight. In this paper, we summarise the main elements of the payload performance, which is described in detail in the accompanying papers. In addition, we describe the satellite performance elements which are most relevant for science, and provide an overview of the plans for scientific operations and data analysis.

Conventional architectures for the implementation of Boolean logic are based on a network of bistable elements assembled to realize cascades of simple Boolean logic gates. Since each such gate has two input signals and only one output signal, such architectures are fundamentally dissipative in information and energy. Their serial nature also induces a latency in the processing time. In this paper we present a new, principally non-dissipative digital logic architecture which mitigates the above impediments. Unlike traditional computing architectures, the proposed architecture involves a distributed and parallel input scheme where logical functions are evaluated at the speed of light. The system is based on digital logic vectors rather than the Boolean scalars of electronic logic. The architecture employs a novel conception of cascading which utilizes the strengths of both optics and electronics while avoiding their weaknesses. It is inherently non-dissipative, respects the linear nature of interactions in pure optics, and harnesses the control advantages of electrons without reducing the speed advantages of optics. This new logic paradigm was specially developed with optical implementation in mind. However, it is suitable for other implementations as well, including conventional electronic devices.

Current ideas regarding the abiogenic synthesis of organic compounds on the planets rest on the theories of Oparin (1) and Urey (2), and on the experiments of Miller (3) and others, showing that the synthesis of biologically important compounds on the primitive earth was favored by the chemically reducing character of the primitive atmosphere. The importance of an excess of a reduced gas such as hydrogen, methane, or ammonia in laboratory simulations of these processes has often been pointed out (4). In view of these findings, it appears a priori unlikely that a synthesis of organic matter would be demonstrable in a gas mixture compositionally similar to the oxidized atmosphere of Mars. This atmosphere consists almost entirely of CO2 (5) with 0.1-0.3% CO (5, 6) and a small, seasonally variable quantity of water (7). Small amounts of other gases are not excluded. The mean surface pressure is about 6.5 mb (8). Solar ultraviolet (UV) reaching the surface is filtered through the CO2, which effectively absorbs wavelengths shorter than 1950 A. Thus, little energy is available at the surface for the activation of C02, CO, or water.We have performed organic synthesis experiments with mixtures of C02, CO, and H20 exposed to UV in the presence of soil or powdered vycor glass. The purpose of these tests was to uncover possible sources of error in an experiment, planned for the first Mars lander, designed to detect biosynthesis of organic matter in Martian soil (9). The The reservoirs were then brought to a total pressure of 1 atm by filling with diluent gas and with about 50 ml of liquid water previously flushed with the diluent gas. The [14C]CO reservoirs were attached to a pyrex manifold which had five positions for attachment of sample chambers. The latter consisted of quartz tubes (1.3 X 8 cm) with a detachable pyrex section containing a stopcock. Each chamber had a gas volume of about 5.5 ml. The chambers were evacuated and flushed with diluent gas, then filled manometrically to 1 atm with ['4C]CO and diluent gases. The pressure in the reservoir was maintained at 1 atm by adding water flushed with diluent gas.The vacuum system contained a liquid nitrogen trap to prevent diffusion of impurities from the mechanical vacuum pump. The vacuum indicator was a Wallace and Tiernan Gage. The gas reservoirs, manifold, and sample chambers were constructed of new glass that presumably had never been exposed to mercury. Also, all glassware was cleaned with 8 N HNO3 to minimize adventitious mercury contamination.The organic soil was an arable, fertile, brown soil with particle size less than 1 mm. Before exposure to [14C]CO, the soil was sterilized overnight in an oven at 1750C and then equilibrated for 1 hr at 100% relative humidity at 23°C.The vycor substratum was 80-100 mesh, highly fractured particles with a surface area of 173 m2/g. Before use, the vycor was heated to 7200C in air and equilibrated with water vapor as described above.Sample chambers containing gas mixtures were irradiated in a horizontal position with the soil...

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