Planck pre-launch status: The optical system

Planck is a scientific satellite that represents the next milestone in space-based research related to the cosmic microwave background, and in many other astrophysical fields. Planck was launched on 14 May of 2009 and is now operational. The uncertainty in the optical response of its detectors is a key factor allowing Planck to achieve its scientific objectives. More than a decade of analysis and measurements have gone into achieving the required performances. In this paper, we describe the main aspects of the Planck optics that are relevant to science, and the estimated in-flight performance, based on the knowledge available at the time of launch. We also briefly describe the impact of the major systematic effects of optical origin, and the concept of in-flight optical calibration. Detailed discussions of related areas are provided in accompanying papers

Planck pre-launch status : The Planck mission

Peer reviewe

The Rosetta Lander ("PHILAE") investigations

Abstract. The paper describes the Rosetta Lander named Philae and introduces its complement of scientific instruments. Philae was launched aboard the European Space Agency Rosetta spacecraft on 02 March 2004 and is expected to land and operate on the nucleus of 67/Churyumov-Gerasimenko at a distance of about 3 AU from the Sun. Its overall mass is ~98 kg (plus the support systems remaining on the Orbiter), including its scientific playload of ~27 kg. It will operate aufomously, using the Rosetta Orbiter as a communication relay to Earth. The scientific goals of its experiments focus on elemental, isotopic, moleculer and mineralogical of the cometary material, the characterization of physical properties of the surface and subsurface material, the large-scale structure and the magnetic and plasma environment of the nucleus. In particular,sub-surface and surface samples will be acquired and sequentially analyzed by a suite of instruments. Measurements will be performed primarily during descent and along the first five days following touch-down. Philae is designed to also operate on a long time-scale, to monitor the evolution of the nucleus properties. Philae is a very integrated project at system, science and management levels, provided by an international consortium. The Philae experiments have the potential of providing unique scientific outcomes, complementing by in situ ground truth the Rosetta Orbiter investigations

Solar Orbiter: Mission and spacecraft design

The main scientific goal of Solar Orbiter is to address the central question of heliophysics: ‘how does the Sun create and control the heliosphere?’ To achieve this goal, the spacecraft carries a unique combination of ten scientific instruments (six remote-sensing instruments and four in-situ instruments) towards the innermost regions of the Solar System, to as close as 0.28 AU from the Sun during segments of its orbit. The orbital inclination will be progressively increased so that the spacecraft reaches higher solar latitudes (up to 34° towards the end of the mission), making detailed studies of the polar regions of the Sun possible for the first time. This paper presents the spacecraft and its intended trip around the Sun. We also discuss the main engineering challenges that had to be addressed during the development cycle, instrument integration, and testing of the spacecraft