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The DENIS project is the first attempt to carry out a complete digitized survey of the southern sky in the range 1–2.5 μm. The main objectives of the programme and the main specifications of the camera and of the data processing stream are briefly outlined

International audience; The Rosetta spacecraft accomplished a flyby of Mars on its way to 67P/Churyumov-Gerasimenko on 25 February 2007. In this paper we describe the measurements obtained by the M channel of the Visual and Infrared Thermal Imaging Spectrometer (VIRTIS-M) and the first scientific results derived from their analysis. The broad spectral coverage of the VIRTIS-M in the IR permitted the study of various phenomena occurring in the Martian atmosphere; observations were further exploited to achieve accurate absolute radiometric calibration. Nighttime data from the VIRTIS-M constrain the air temperature profile in the lower atmosphere (5-30 km), using variations in CO2 opacity at 4.3 mum. A comparison of this data with the global circulation model (GCM) by Forget et al. (1999) shows a trend of slightly higher air temperature in the VIRTIS-M retrievals; this is accompanied by the presence of moderate decreases (˜5 K) in large sections of the equatorial region. This is potentially related to the occurrence of water ice clouds. Daytime data from the VIRTIS-M reveal CO2 non-local thermodynamic equilibrium emission in the high atmosphere. A mapping of emission intensity confirms its strict dependence on solar zenith angle. Additionally, devoted limb observations allowed the retrieval of vertical emission intensity profiles, indicating a peak around 105 km in southern tropical regions. Ozone content can be effectively monitored by the emission of O2 (a1Deltag) at 1.27 mum. Retrieved emission intensity shows that polar regions are particularly rich in ozone. Aerosol scattering was observed in the 1-2.5 mum region above the night region above the night disk, suggesting the occurrence of very high noctilucent clouds.

International audience; The VIRTIS (Visual IR Thermal Imaging Spectrometer) experiment has been one of the most successful experiments built in Europe for Planetary Exploration. VIRTIS, developed in cooperation among Italy, France and Germany, has been already selected as a key experiment for 3 planetary missions: the ESA-Rosetta and Venus Express and NASA-Dawn. VIRTIS on board Rosetta and Venus Express are already producing high quality data: as far as Rosetta is concerned, the Earth-Moon system has been successfully observed during the Earth Swing-By manouver (March 2005) and furthermore, VIRTIS will collect data when Rosetta flies by Mars in February 2007 at a distance of about 200 kilometres from the planet. Data from the Rosetta mission will result in a comparison – using the same combination of sophisticated experiments – of targets that are poorly differentiated and are representative of the composition of different environment of the primordial solar system. Comets and asteroids, in fact, are in close relationship with the planetesimals, which formed from the solar nebula 4.6 billion years ago. The Rosetta mission payload is designed to obtain this information combining in situ analysis of comet material, obtained by the small lander Philae, and by a long lasting and detailed remote sensing of the comet, obtained by instrument on board the orbiting Spacecraft. The combination of remote sensing and in situ measurements will increase the scientific return of the mission. In fact, the “in situ” measurements will provide “ground-truth” for the remote sensing information, and, in turn, the locally collected data will be interpreted in the appropriate context provided by the remote sensing investigation. VIRTIS is part of the scientific payload of the Rosetta Orbiter and will detect and characterise the evolution of specific signatures – such as the typical spectral bands of minerals and molecules – arising from surface components and from materials dispersed in the coma. The identification of spectral features is a primary goal of the Rosetta mission as it will allow identification of the nature of the main constituent of the comets. Moreover, the surface thermal evolution during comet approach to sun will be also studied.

A Raytheon HgCdTe (cut-off 5 μm) 436×270 Infrared Focal Plane Array (IRFPA) is mounted at two of the three focal planes of an infrared imaging spectrometer, VIRTIS, on board the ESA/ROSETTA cometary mission. VIRTIS is comprised of a mapping spectrometer (-M) under Italian responsibility (Officine Galileo) and a high-resolution spectrometer (-H) under French responsibility (Observatoire de Paris, Meudon).

During the last 30 years, the Space Research Department (DESPA) of Paris Observatory has developed infrared instrumentation for space and ground-based telescopes. First, we present the PbS linear detector of the ISM IR imaging spectrometer of the Phobos mission. Then the CID InSb focal plane of ISOCAM-SW is described. The studies of this CID InSb focal plane allowed us to develop an IR camera for the first astronomical observations using adaptive optics. We also describe the linear array built for the OMEGA imaging spectrometer of the Mars 96 mission. The last chapter is dedicated to the IR spectrometer of the Huygens probe. To conclude, the needs and challenges in the area of mid-band infrared astronomy are discussed.

VIRTIS, the infrared imaging spectrometer of the ESA/ROSETTA mission, to be launched in January 2003, is devoted to the in-orbit remote sensing study of comet P/46 Wirtanen. Within the infrared imaging spectrometer VIRTIS, the high spectral resolution channel, VIRTIS-H, has for main scientific objectives to study the fine spectral details of the coma and cometary nucleus, with their composition and physical parameters, in parallel with the imaging spectrometer channel VIRTIS-M. The instrument is a cross-dispersor spectrometer, working in the range 2 - 5 micrometers , at about approximately 1200 spectral resolving power. Its design consists of a telescope, an entrance slit, followed by a collimator, and a prism separating 8 orders of a grating

Two scientific programs will work simultaneously on adjacent regions of the sky: Asteroseismology and Exoplanet Detection. Ultra high photometry, good stability and a wide field are the main goals. We explain the requirements and the definition of the payload and we present the focal box with four EEV 42-80 CCDs. The last section is dedicated to the special CCD calibration for highly stable stellar photometry.

This paper presents the first I-band photometric catalog of the brightest galaxies extracted from the Deep Near Infrared Survey of the Southern Sky (DENIS) An automatic galaxy recognition program has been developed to build this provisional catalog. The method is based on a discriminating analysis. The most discriminant parameter to separate galaxies from stars is proved to be the peak intensity of an object divided by its array. Its efficiency is better than 99%. The nominal accuracy for galaxy coordinates calculated with the Guide Star Catalog is about 6 arcseconds. The cross-identification with galaxies available in the Lyon-Meudon Extragalactic DAtabase (LEDA) allows a calibraton of the I-band photometry with the sample of Mathewson et Al. Thus, the catalog contains total I-band magnitude, isophotal diameter, axis ratio, position angle and a rough estimate of the morphological type code for 20260 galaxies. The internal completeness of this catalog reaches magnitude $I_{lim}=14.5$, with a photometric accuracy of $\sim 0.18m$. 25% of the Southern sky has been processed in this study. This quick look analysis allows us to start a radio and spectrographic follow-up long before the end of the survey., 13 pages, 17 figures, to appear A&A Supl. S

The visible infrared thermal imaging spectrometer (VIRTIS) is one of the principal payloads to be launched in 2003 on ESA's Rosetta spacecraft. Its primary scientific objective s are to map the surface of the comet Wirtanen, monitor its temperature, and identify the solids and gaseous species on the nucleus and in the coma. VIRTIS will also collet data on two asteroids, one of which has been identified as Mimistrobell. The data is collected remotely using a mapping spectrometer co-boresighted with a high spectral resolution spectrometer. The mapper consists of a Shafer telescope matched to an Offner grating spectrometer capable of gathering high spatial, medium spectral resolution image cubes in the 0.25 to 5 micrometers waveband. The high spectral resolution spectrometer uses an echelle grating and a cross dispersing prism to achieve resolving powers of 1200 to 300 in the 1.9 to 5 micrometers band. Both sub-systems are passively cooled to 130 K and use two Sterling cycle coolers to enable two HgCdTe detector arrays to operate at 70 K. The mapper also uses a silicon back-side illuminated detector array to cover the ultra-violet to near-infrared optical band.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Proposed to both the French and the European Space Agency as one possible small mission, SPICE is a project for a dedicated small satellite for a near-IR spectroscopic all-sky survey. The instrument would cover the spectral range 1.8 – 3.6 μm, possibly extended to 1.8 – 7 μm, at a resolution of ≈ 100, with pixels of 1 arc-min. The excellent sensitivity (0.02 MJy sr-1) results from: i) the quasi-zero level of background due to the efficient passive cooling of the whole experiment; ii) the use of large format arrays; iii) the non-stop observing mode (drift-scanning). The spectral domain, complementing the one of ISO, partially opaque from the ground, is specially rich in spectral features tracing stars and all components of the Interstellar Medium (molecular, atomic and ionized gas, dust). With a cooling below 80 K of the focal instrument, then it becomes possible to consider doubling the spectral domain and to cover the whole 1.8-7 μm range.

We briefly report on the first astronomical results obtained with the DENIS camera at the ESO 1 meter telescope.

ISOCAM, the camera of the Infrared Space Observatory, will image the sky at various angular and spectral resolutions in the wavelength range 2.5 to 17 microns. We recall the main steps of the development, leading to the delivery of the flight model to ESA, and we outline some of the scientific programs to which it will be applied.

The most recent projects in which the space research department of the Paris Observatory has participated are summarized. These include the Common User Near-Infrared CIRCUS (Camera Infrared Rouge Courtes longueurs d'onde pour Utilisation au Sol) camera, the adaptive optics COME-ON system, the High-Resolution Near-IR Camera for VLT, and the on-board IR 2D array camera of the ISO satellite, called ISOCAM. Technical characteristics and performance data for these instruments are listed.

The Infrared Space Observatory (ISO) camera (ISOCAM) is designed to map selected regions of the sky in the spectral region from 2.5 to 17 μm at various spatial and spectral resolutions and at high sensitivity (at >4 μm

An infrared camera for use in ground based astronomical observations in the 1-5 microns region of the spectrum under low photon flux , has been developped in Meudon Observatory . This camera uses a 32 x 32 pixels InSb Charge Injection Device built by SAT (*) . We hereafter present a description of the camera , its performances and some results , recently obtained at OPMT and ESO with 2 and 2.2 m telescopes .© (1987) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The use at liquid helium temperature of a InSb-CID detector array differs significantly from opera-tion at conditions usually adopted by the manufacturer (77K). In particular, the dark current behaviour hugely changes between the two temperatures. Only the tunnel current, independant of temperature conditions, is still active at 4.2K while the thermal-family currents vanish. We have studied the tunnel current of one InSb-MIS detector to determine its suitability to the low background conditions that will be met in the space experiment ISO. The search for the maximum integration time and the best quantum efficiency, the constraint about the photonic response linearity (especially at low photon flux), and the reduction of the readout noise constitute the main points of this study. Moreover, laboratory measurements showed secondary effects due to the detector (lag) or to the wiring (crosstalk). The CID array reactions to high energy radiations (Gamma rays) are finally discussed.© (1988) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper presents the CIRCUS infrared camera and recent results in extragalactic astronomy obtained using this 32 x 32 array camera. Observations were carried on starburst galaxies, 3.3μm PAH emission line at large scale in NGC 891 and the twin quasar Q0957+561.