References of "Fridlund, Malcolm"
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See detailThe Search for Worlds Like Our Own
Fridlund, Malcolm; Eiroa, Carlos; Henning, Thomas et al

in Astrobiology (2010), 10(1), 5-17

The direct detection of Earth-like exoplanets orbiting nearby stars and the characterization of such planets -- particularly, their evolution, their atmospheres, and their ability to host life ... [more ▼]

The direct detection of Earth-like exoplanets orbiting nearby stars and the characterization of such planets -- particularly, their evolution, their atmospheres, and their ability to host life -- constitute a significant problem. The quest for other worlds as abodes of life has been one of mankind's great questions for several millennia. For instance, as stated by Epicurus 300 BC: Other worlds, with plants and other living things, some of them similar and some of them different from ours, must exist. Demokritos from Abdera (460-370 BC), the man who invented the concept of indivisible small parts - atoms - also held the belief that other worlds exist around the stars and that some of these worlds may be inhabited by life-forms. The idea of the plurality of worlds and of life on them has since been held by scientists like Johannes Kepler and William Herschel, among many others. Here, one must also mention Giordano Bruno. Born in 1548, Bruno studied in France and came into contact with the teachings of Nicolas Copernicus. He wrote the book De l'Infinito, Universo e Mondi in 1584, in which he claimed that the Universe was infinite, that it contained an infinite amount of worlds like Earth, and that these worlds were inhabited by intelligent beings. At the time, this was extremely controversial, and eventually Bruno was arrested by the church and burned at the stake in Rome in 1600, as a heretic, for promoting this and other equally confrontational issues (though it is unclear exactly which idea was the one that ultimately brought him to his end). In all the aforementioned cases, the opinions and results were arrived at through reasoning--not by experiment. We have only recently acquired the technological capability to observe planets orbiting stars other than 6our Sun; acquisition of this capability has been a remarkable feat of our time. We show in this introduction to the Habitability Primer that mankind is at the dawning of an age when, by way of the scientific method and 21st-century technology, we will be able to answer this fascinating controversial issue that has persisted for at least 2500 years. [less ▲]

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See detailDarwin---an experimental astronomy mission to search for extrasolar planets
Cockell, Charles S; Herbst, Tom; Léger, Alain et al

in Experimental Astronomy (2009), 23

As a response to ESA call for mission concepts for its Cosmic Vision 2015--2025 plan, we propose a mission called Darwin. Its primary goal is the study of terrestrial extrasolar planets and the search for ... [more ▼]

As a response to ESA call for mission concepts for its Cosmic Vision 2015--2025 plan, we propose a mission called Darwin. Its primary goal is the study of terrestrial extrasolar planets and the search for life on them. In this paper, we describe different characteristics of the instrument. [less ▲]

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See detailCoRoT Measures Solar-Like Oscillations and Granulation in Stars Hotter Than the Sun
Michel, Eric; Baglin, Annie; Auvergne, Michel et al

in Science (2008), 322

Oscillations of the Sun have been used to understand its interior structure. The extension of similar studies to more distant stars has raised many difficulties despite the strong efforts of the ... [more ▼]

Oscillations of the Sun have been used to understand its interior structure. The extension of similar studies to more distant stars has raised many difficulties despite the strong efforts of the international community over the past decades. The CoRoT (Convection Rotation and Planetary Transits) satellite, launched in December 2006, has now measured oscillations and the stellar granulation signature in three main sequence stars that are noticeably hotter than the sun. The oscillation amplitudes are about 1.5 times as large as those in the Sun; the stellar granulation is up to three times as high. The stellar amplitudes are about 25% below the theoretic values, providing a measurement of the nonadiabaticity of the process ruling the oscillations in the outer layers of the stars. [less ▲]

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See detailGENIE: High-Resolution Study of Debris Disks
Absil, Olivier ULg; Augereau, Jean-Charles; Den Hartog, Roland et al

in Richichi, A.; Delplancke, F.; Paresce, F. (Eds.) et al The Power of Optical/IR Interferometry: Recent Scientific Results and 2nd Generation Instrumentation (2008)

GENIE, the Ground-based European Nulling Interferometer Experiment, will combine the lights collected in the L’ band by two VLT telescopes in a destructive way, thereby revealing the thermal and/or ... [more ▼]

GENIE, the Ground-based European Nulling Interferometer Experiment, will combine the lights collected in the L’ band by two VLT telescopes in a destructive way, thereby revealing the thermal and/or scattered emission of faint objects in the close neighbourhood of the target star. A prime scientific goal for GENIE thus consists in the detection and characterization of debris disks around nearby Vega-type stars. Thanks to its high angular resolution and operating wavelength (3.8 µm), GENIE will be particularly sensitive to the thermal emission from the warm dust standing within a few AU from the star, a part of the disks which is not accessible with current detection methods (IR photometric excesses, sub-millimeter imaging, …). In this paper, we investigate the capabilities of GENIE to detect and characterize the physical parameters of the debris disk around zeta Leporis, a prototypical Vega-type star suspected to harbour a warm dust component in its debris disk (Fajardo-Acosta et al., AJ 115, 2101). This study is then extended to the detection of faint exozodiacal disks around typical Darwin/TPF targets, thereby demonstrating the very high potential of GENIE in the field of high-contrast imaging. [less ▲]

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See detailCharacterisation of disks around YSOs with GENIE
Kaltenegger, Lisa; Absil, Olivier ULg; Eiroa, Carlos et al

in Fridlund, Malcolm; Henning, Thomas (Eds.) Towards Other Earths: DARWIN/TPF and the Search for Extrasolar Terrestrial Planets (2003, October 01)

Recent interferometric observations show that the interfered near-IR size of the circumstellar material around Young Stellar Object (YSO) are larger than those expected from accretion disk models. There ... [more ▼]

Recent interferometric observations show that the interfered near-IR size of the circumstellar material around Young Stellar Object (YSO) are larger than those expected from accretion disk models. There are currently different models that account for the excess IR emission of Young Stellar Objects (YSO). At the same time, the answers to many questions on the evolutionary status and the origin of the activity and variability depend critically on the relative importance of circumstellar distribution of material in disks or envelopes at different spatial scales. Operating at mid-infrared wavelengths, the Ground-based European Nulling Interferometer Experiment (GENIE) will be particularly sensitive to warm circumstellar dust and will thus provide the opportunity to characterize dust disks around YSOs. Observations with GENIE will enable us to investigate the properties of the circumstellar dust, which are responsible for the excess near-infrared fluxes. The nulling of the central star will bring out the disk in much more detail and hence put stronger constraints on these models. [less ▲]

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