European Space Agency Science Research Articles

Turbulence Heating ObserveR – satellite mission proposal

The Universe is permeated by hot, turbulent, magnetized plasmas. Turbulent plasma is a major constituent of active galactic nuclei, supernova remnants, the intergalactic and interstellar medium, the solar corona, the solar wind and the Earth’s magnetosphere, just to mention a few examples. Energy dissipation of turbulent fluctuations plays a key role in plasma heating and energization, yet we still do not understand the underlying physical mechanisms involved. THOR is a mission designed to answer the questions of how turbulent plasma is heated and particles accelerated, how the dissipated energy is partitioned and how dissipation operates in different regimes of turbulence. THOR is a single-spacecraft mission with an orbit tuned to maximize data return from regions in near-Earth space – magnetosheath, shock, foreshock and pristine solar wind – featuring different kinds of turbulence. Here we summarize the THOR proposal submitted on 15 January 2015 to the ‘Call for a Medium-size mission opportunity in ESAs Science Programme for a launch in 2025 (M4)’. THOR has been selected by European Space Agency (ESA) for the study phase.

Europe's Path To Mars: The European Space Agency's Mars Express Mission

Mars Express is the first planetary mission accomplished by the European Space Agency (ESA). Launched in early June 2003, the spacecraft entered Mars's orbit on Christmas day of that year, demonstrating the new European commitment to planetary exploration. Following a failed attempt in the mid-1980s, two valid proposals for a European mission to Mars were submitted to ESA's decision-making bodies in the early 1990s, in step with renewed international interest in Mars exploration. Both were rejected, however, in the competitive selection process for the agency's Science Programme. Eventually, the Mars Express proposal emerged during a severe budgetary crisis in the mid-1990s as an exemplar of a “flexible mission” that could reduce project costs and development time. Its successful maneuvering through financial difficulties and conflicting scientific interests was due to the new management approach as well as to the public appeal of Mars exploration. In addition to providing a case study in the functioning of the ESA's Science Programme, the story of Mars Express discussed in this paper provides a case study in the functioning of the European Space Agency's Science Programme and suggests some general considerations on the peculiar position of space research in the general field of the history of science and technology.

Venus Express: a Fascinating Journey to Our Planet-neighbor

Venus Express is the first mission of the European Space Agency (ESA) to Venus. The mission aims at the global and long-term remote and in-situ survey of the atmosphere and the plasma environment from orbit and addresses some aspects of surface physics. The spacecraft, based on the Mars Express bus modified for the conditions at Venus, provides a versatile platform for nadir and limb observations as well as solar, stellar, and radio occultation. The payload consists of seven experiments and includes a powerful suite of imagers and spectrometers, instruments for in-situ analysis of the planetary plasma, and a radio science experiment. For the first time, the investigations make systematic use of the infrared transparency “windows” to probe the lower atmosphere. The polar and highly elliptic 24 hours orbit with pericenter altitude of about 200 km over the Northern polar region and apocenter distance of 66,000 km provides a fortunate combination of global views of the planet with close-up imaging. The spacecraft was inserted in orbit on April 11, 2006 and completed the nominal mission on October 2, 2007. The mission is extended till the end of 2012. Venus Express is a part of the ESA's science program for the exploration of the solar system, which includes missions to the Sun, Mercury, Venus, the Moon, Mars, comets and asteroids.

The gamma-ray lens technology reference study

The Science Payload and Advanced Concepts Office (SCI-A) at the European Space Agency (ESA) conducts technology reference studies (TRSs), hypothetical science driven missions that are not currently part of the ESA science programme. The purpose of the TRS programme is to establish a series of preliminary scientific requirements and, from these, define technology development activities required in order to realise similar potential future missions. One such TRS has been conducted on a gamma-ray lens (GRL) mission. In response to the realisation that greatly increased sensitivity in gamma-ray astronomy requires a focusing optic, the GRL TRS investigates the application of a broad bandpass Laue crystal lens, a novel high-energy focusing optic, to a gamma-ray observatory. Two mission concepts are considered: a Soyuz Fregat, dual-launch mission and a larger Ariane 5 mission. Due to the long focal length of the optics, both mission scenarios require formation flying between two spacecraft. This paper focuses on the establishment of a baseline mission design capable of meeting a set of reference science objectives. The key mission and spacecraft design drivers are introduced and preliminary mass budgets are established. Finally, necessary areas for future study and technology development, key to the realisation of a gamma-ray focusing mission using Laue crystals, are presented, in line with the main objective of TRSs.

The PLATO space mission: studying planetary transits and stellar oscillations simultaneously

AbstractPLATO (PLAnetary Transits and Oscilliations of stars) is a proposed mission of the European Space Agency's Science programme Cosmic Vision 2015–2025, currently under industrial study, and with a planned launch by the end of 2017. Its task is to better understand the properties of exoplanetary systems. As such it will detect and characterise exoplanets using their transit signature in front of a large sample of bright stars and simultaneously measuring the seismic oscillations of the parent star of these exoplanets. The mission will be orbiting the Sun-Earth L2 point, which provides a stable thermal environment and maximum uninterrupted observing efficiency. The payload consists of a number (> 28) of individual catadioptric telescopes, covering > 550 sq. degrees. Since the goal is to search for terrestrial exoplanets within the habitable zone of their host stars, and carry out asteroseismological observations of the host stars, very high photometric precision, high time resolution, and high duty-cycle visible photometry is required. Ground-based observations are needed to complement the observations made by PLATO to allow for further exoplanetary characterization. This paper consists of a summary of the preliminary results achieved by the ESA internal pre-assessment study.

Hubert Curien

Hubert Curien

New Science Chief Must Juggle Missions and Politics

With calls to tie the European Space Agency (ESA) more closely to the business and security sectors (see sidebar), space scientists hope David Southwood, who will take over next May as ESA's science director, can nurture the agency's research with the skill he showed transforming its earth sciences division. Experts say he's up to the task.

The European Space Agency and its successful Science Programme

The article gives, first of all, a general presentation of the European Space Agency (ESA), followed by a more detailed outline of the ESA's Science Programme, its content, resources, organization, advisory structure and decision procedures. The various types of missions and the place they occupy in the programme are described. From a scientific point of view, these missions fit into four main themes of research, which are also potential ‘roadmaps’ for international collaboration. In the second part of the article, an outline is given of most of the projects that have been already undertaken, are in process or are being planned at the present time.

The European Space Agency and its successful Science Programme

The article gives, first of all, a general presentation of the European Space Agency (ESA), followed by a more detailed outline of the ESA's Science Programme, its content, resources, organization, advisory structure and decision procedures. The various types of missions and the place they occupy in the programme are described. From a scientific point of view, these missions fit into four main themes of research, which are also potential ‘roadmaps’ for international collaboration. In the second part of the article, an outline is given of most of the projects that have been already undertaken, are in process or are being planned at the present time.

Europe Forges a Plan in Collaboration With Industry

[ Helen Gavaghan ][1] Last month, a European Space Agency (ESA) task force outlined a new strategy for supporting Earth-observation missions that would make industry a full partner in designing, developing, and funding an entire class of missions. The proposal, previewed at a crowded meeting of industrialists at ESA's science and technology center in Noordwijk, the Netherlands, on 18 December, would divide future Earth-observation programs into two types: scientific mission, which would be fully paid for out of ESA's budget, and applications missions, which would be private initiatives or risk- and cost-sharing partnerships between the agency and industry, which ESA would join only if the industrial sponsors already have purchasers for their data lined up. This new plan, which will be fleshed out at ESA headquarters over the next few months and presented to the organization's member states this summer, is designed to fill a looming gap in ESA's Earth-observation program. [1]: http://www.sciencemag.org#name