09/2015: Presentations of the "Solar Metrology, Needs and Methods II" Meeting
One year after the first meeting in Paris, the CNES, the LATMOS and the STCE organized the second edition of the meeting "Solar Metrology, Needs and Methods". It took place at the Royal Observatory of Belgium in Brussels on Sepemtber 21 to 23 2015.
It intent was to review the recent progresses in those two fields, to analyze the possibilities, but also the limitations of the current ground- or space-based observation facilities, and to discuss the major challenges for future missions.
Presentations made during the Meeting:
Moday September 21
- Dr. MEFTAH, Mustapha - Introduction
- Dr. DEWITTE, Steven - The RMIB space odissey: new frontiers
- Dr. SHAPIRO, Alexander - Can we use stellar photometric data to better understand solar variability?
- Dr. VERMA, VIRENDRA - On long-term behavior of North-South Asymmetry of Solar Phenomena
- Dr. SIGISMONDI, Costantino - 2016 transit of Mercury and the solar diameter: new opportunities after the Venus transits
- Dr. DAME, Luc - SUITS /SWUSV : A Solar - Terrestrial Space Weather & Climate Investigation
- Solspec Discussion
Mardi 22 septembre
- Dr. DEWITTE, Steven - Total Solar Irradiance measurements over the last 30 years and reconstruction over the last 300 years
- Dr. HAUCHECORNE, Alain - Solar forcing of the Earth climate: the role of the middle atmosphere-troposphere coupling
- Dr. BUSH, Rock - Measurements of the Solar Oblateness during the SDO Mission
- Dr. LAMY, Philippe - Projet SOLIMB : métrologie du bord du soleil et détermination de son diamètre pendant les éclipses solaires
- Prof. EMILIO, MARCELO - Using HMI-SDO for limb seismology
- Dr. WAUTERS, Laurence - Mid-term Periodicities of the LYRA data spectrum
- Mr. DAMMASCH, Ingolf - Long-term variability of LYRA data
- Dr. DEWITTE, Steven - The value of the Solar Constant
- Dr. MEFTAH, Mustapha - Five Years of Solar Observation with PICARD
- Dr. CESSATEUR, Gaël - Solar Spectral Irradiance observations from the PICARD/PREMOS radiometer
- Metrology Discussion
Mercredi 23 septembre
- Dr. BOLSÉE, David - The Solar Spectral Irradiance in the Near IR
- Dr. THUILLIER, Gerard - The 2008 Minimum Solar Spectral Irradiance from ISS SOLAR Spectrometers Measurements
- Dr. SHAPIRO, Alexander - The quest for understanding solar brightness variation. How can SOLSPEC contribute?
- Dr. BENMOUSSA, Ali - Space-based instrument developments for UV solar observations - detector technology -
- DOMINIQUE, Marie - Progress towards understanding the degradation affecting the PROBA2/LYRA instrument
- Dr. THUILLIER, Gerard - The SOLSPEC Spectrometers onboard the International Space Station
- Dr. HOCHEDEZ, Jean-François - Non-linearties in SODISM telescope
- Dr. MEFTAH, Mustapha - SERB, a nano-satellite dedicated to Sun-Earth relationship
- Dr. SARKISSIAN, Alain - Atmospheric Research and Monitoring with a SATellite (ARM-SAT) for Sun-Earth measurements
- Dr. LEFEVRE, Laure - The new and improved Sunspot Number SN
02/2015: Presentations of the "Solar Metrology, Needs and Methods" Symposium
CNES and LATMOS organized the "Solar Metrology, Needs and Methods" symposium in Paris that took place from October 7th to 9th, 2014.
The goal of this symposium was to meet together scientists involved in physics, metrology and modeling of the Sun to confront the available observations of solar parameters (total and spectral irradiance, solar diameter and shape, helioseismology, ...) from existing space missions (PICARD, SOHO, SDO) with the needs of solar models.
Agenda of the symposium:
Tuesday, October 7
14h20-15h30: Data for Climate Science
Joanna HAIGH - Imperial College of London, UK: Solar spectral variability and the Earth's atmosphere
Andrew SCHURER - The University of Edinburgh, UK: Detection and attribution of the role of solar and other forcings over the last millennium
Sébastien BOSSAY - LATMOS-IPSL, France: Sensitivity of tropical stratospheric and mesospheric ozone to short term solar variability: observations vs chemistry climate model simulations
16h-17h30: Space Era Data vs Historical Records
Edouard BARD - CEREGE, Aix-en-Provence, France: Cosmogenic isotopes as proxies for the solar activity
Mélanie BARONI - CEREGE, Université d'Aix-Marseille, France: The 10Be record recovered from an Antarctic ice core as a solar activity proxy: limitations and possibilities
Frédéric CLETTE - Royal Meteorological Institute of Belgium, Brussels: The new Sunspot Number: a full recalibration
Matthieu KRETZSCHMAR - LPC2E, University of Orleans, France: Validation of solar spectral irradiance datasets
Wednesday, October 8
9h00-10h30: Solar Modelling
Paul CHARBONNEAU - University of Montreal, Canada: Deep-seated modulation of the quiet-sun irradiance by the solar magnetic cycle
Cassandra BOLDUC - - University of Montreal, Canada: Modelling TSI with a Monte Carlo simulation of active region decay
Jean-Pierre BARRIOT - Geodesy Observatory of Tahiti, French Polynesia: Comparative determinations of the solar diameter from light curves taken during the solar eclipses of November 13, 2012 and November 3, 2013
Jean-Pierre ROZELOT - Planète Sciences Méditerranée, Grasse, France: Solar quadruple moment and relativistic gravitation contributions
11h-12h30: Solar Modelling: Tentative interpretation of the Data
Alexander SHAPIRO - PMOD/WRC, Davos Dorf, Switzerland: Variability of the solar irradiance: what we do and do not know
Rosaria SIMONIELLO - CEA SAP, Gif-sur-Yvette, France: SOLar - Stellar - ICE (SOLSTICE) connection: understanding solar / stellar magnetic activity and its variability
Jose Luis BALLESTER - University of Baleares, Spain: Solar Atmospheric metrology using prominence oscillations
Anatoliy VUIETS - LPC2E, University of Orleans, France: An empirical approach to the modelling of the solar spectral irradiance in the UV
14h-15h30: Solar Irradiance: Tentative interpretation of the Data
Gérard THUILLIER - LATMOS CNRS, Guyancourt, France: Modelling the solar spectral irradiance
David BOLSÉE - BIRA-IASB, Brussels, Belgium: SOLAR SOLSPEC on ISS: Solar Spectral Irradiance variability during the Solar Cycle 24
Wilnelia ADAMS - PMOD/WRC, Davos Dorf, Switzerland: A new model of solar irradiance: reconstructing the past and forecasts into the future
Steven DEWITTE - Royal Meteorological Institute of Belgium, Brussels: Total solar irradiance measurements: quantification of the solar radiative forcing of the earth's climate from 30 years of observations from space
Thursday, October 9
9h-12h50: Recent Solar Missions
Greg KOPP - University of Colorado, USA: High "flux" of total solar irradiance missions
Mustapha MEFTAH - LATMOS, France: Solar astrophysical fundamental parameters
Sébastien COUVIDAT - Stanford University, USA: A brief review of 4+ years of SDO/HMI scientific results
David SALABERT - CEA Saclay, Gif-sur-Yvette, France: Solar magnetic activity inferred by helioseismology: the weak solar cycle 24
Marcelo EMILIO - Ponta Grossa State University, Brazil: Using 2012 Venus transit for solar metrology
Rock BUSH - Stanford University, USA: The constant size and sharp of the sun
Rabah IKHLEF - Observatoire de la Côte d'Azur, Nice, France: Seeing measurements for ground based solar astrometry
Jin QI - NSMC, Beijing, China: The new TSI observations from FY-3C Solar Irradiance Monitor
Els JANSSEN - Royal Meteorological Institute of Belgium, Brussels: Revision of the value of the solar constant and Sova-Picard TSI results
14h-15h30: Future Solar Missions
Sylvaine TURCK-CHIEZE - CEA, CE Saclay, Gif-sur-Yvette, France: Why new space solar measurements and which?
Alain HAUCHECORNE - CNRS, France: SERB, a nano-satellite to study the Sun and the Earth
Luc DAME - LATMOS, Guyancourt, France: A UV telescope for space weather and solar variability studies (SUAVE)
Erik RICHARD - LASP, University of Colorado, Boulder, USA: The future of solar spectral irradiance measurements from space: ISS TSIS and beyond
Alain HAUCHECORNE, Steven DEWITTE, Paul CHARBONNEAU: Discussion on different points of the meeting
Grzegorz MICHALEK - Jagiellonian University, Poland : Dynamics of CMEs in the LASCO field of view
Hongrui WANG - Changchun Institute of Optics, Chinese Academy of Sciences, China : Total Solar Irradiance Monitor on FY-3 satellites, instrument and space operations
Cyril BAZIN - IAP, Paris, France : Contribution of eclipse flash spectra for defining the true solar edge
Abdanour IRBAH - LATMOS, France : Thermal effects on solar images recorded in space
Zhenling YANG - Changchun Institute of Optics, Chinese Academy of Science, China : Experimental characterization and correction of nonequivalence of Solar Irradiance Absolute Radiometer
Jean-Pierre ROZELOT - Planète Sciences Méditerranée, Grasse, France : Wavelength dependence of the Solar Oblateness
Thierry CORBARD - Observatoire de la Côte d'Azur, Nice, France : Solar internal flows from PICARD/SODISM and SDO/HMI helioseismic signal
Thierry CORBARD - Observatoire de la Côte d'Azur, Nice, France : Astronomical refraction correction for ground-based full disk solar astrometry
Thierry DUDOK DE WIT - LPC2E, University of Orleans, France : Making of solar spectral irradiance composites out of multiple datasets
Thierry DUDOK DE WIT - LPC2E, University of Orleans, France : 60 years of solar radio proxies for characterizing the upper atmosphere
Alain HAUCHECORNE - CNRS, France : Revisiting the determination of solar oblateness from space observations using an optimization method
Micha SCHOLL - CNRS/LPC2E, University of Orleans, France : Can we find a long-term solar trend?
Margit HABERREITER - PMOD/WRC, Davos Dorf, Switzerland : FP7 SOLID - Latest advances from The First European Comprehensive SOLar Irradiance Data Exploitation (SOLID)
10/07-10/09/2014: "Solar Metrology, Needs and Methods" Symposium in Paris
From October 7th to 9th, 2014, CNES and LATMOS organize the "Solar Metrology, Needs and Methods" symposium in Paris.
The goal of this symposium is to meet together scientists involved in physics, metrology and modeling of the Sun to confront the available observations of solar parameters (total and spectral irradiance, solar diameter and shape, helioseismology, ...) from existing space missions (PICARD, SOHO, SDO) with the needs of solar models.
The objectives are to evaluate if these observations are adequate in terms of methods and accuracy to constraint the solar models, to determine if some parameters are missing and to discuss in which direction we have to improve them for future solar missions.
04/04/2014: Last telecommand sent to PICARD satellite
The last telecommand was sent to PICARD satellite during its passage at 10h56 over Toulouse.
A presentation of the mission and its scientific results was given at Toulouse Space Center.
- Michel Rouzé : Tout ce que vous avez toujours voulu savoir sur la mission Picard
- M. Meftah : La charge utile PICARD
- Alain Hauchecorne : Objectifs et résultats scienentifiques de PICARD
- Florence Duchevet : Les expérimentations technologiques de fin de vie
- Christine Fallet : Les expérimentations fin de vie autour du sous système de contrôle d'attitude et d'orbite
12/03/2013: A solar eclipse happened on November 3, 2013
It was the ninth solar eclipse of this century and the second eclipse of the year 2013. The Moon played with the Sun for an exceptional hybrid eclipse, annular at the beginning, then total. This eclipse could be seen from the American continent to the African continent. The telescope of space mission PICARD could "photograph" this event. Several observations have been done at different wavelengths (393.37, 535.7 and 607.1 nm). The Sun reveals the increase of activity that it is going through by showing dark spots and bright faculae. In fact, the Sun emitted a big eruption on November 5, 2013.
12/2013: SODISM-II images, Ca II at 393 nm acquired in Calern during the summers 2012 and 2013
The PICARD-SOL mission is operational since May 2011. The images above were obtained in the Ca II absorption line at 393 nm. They give information about the chromospheric activity of the Sun since this date (the data are available through the mission's PI, Alain Hauchecorne).
See the complete article on the Côte d'Azur Observatory website
10/21/2013: The PICARD data are now available to the scientific community
The PICARD data are now available to the scientific community on the web site: http://picard.busoc.be with the following elements:
For a more specific search of the SODISM data (Level N1), the catalog of the SODISM data is on-line on the web site http://picso.busoc.be
A "Help" button is placed on the PICSO homepage. It sends back to an "assistance" page for the use of the search tool (and to get the selected data).
This site is accessible with the same: Username: GISGENPI, and Password: 4LdL!v;8
In case of problem or for further information, you can contact: Michel Rouzé
For scientific questions about the mission, please contact the mission's PI: Alain Hauchecorne.
09/25-09/26/2013: PICARD scientific workshop at CNES Headquarters
The workshop gathered the Principal Investigators, the Co-Investigators, as well as the PICARD Guest Investigators. Its objective was to present the latest scientific results, to tackle some important technical problems for the scientific exploitation of the data, to identify some possible cooperations between laboratories, etc.
Some of the presentations are available in the agenda below.
Agenda of the Workshop
Wednesday 25th September
- 09:30 Welcome
- 10:00 A. Hauchecorne: PICARD Scientific objectives
- 10:25 M. Rouzé: The PICARD mission
- 10:50 P. Boumier: The MEDOC solar data centre
- 11:15 Coffee break
- 11:35 M. Meftah: SODISM behaviour in flight
- 12:00 J.F. Hochedez: SODISM optical modelling
- 12:25 G. Cessateur: The PREMOS/PICARD Radiometer: An overview after 3 Years of Observations
- 12:50 Lunch break
- 14:00 E. Janssen: The method to revise the absolute level of the DIARAD radiometer type
- 14:25 S. Dewitte: Revision of the absolute level of DIARAD radiometer type
- 14:50 Zhu Ping: The BOS sensor and its performance in Space
- 15:15 M. Kretschmar: Analysis of spectral irradiance observed by PREMOS: degradation and comparison with SODISM and various proxies
- 15:40 Coffee break
- 15:55 G Thuillier: The Solar spectral irradiance at solar acivity minimum during the transition cycles 23 to 24: A contribution to the PICARD-Climate program
- 16:20 S Bekki: Impact of short-term solar variability on middle atmospheric ozone
- 16:45 S Couvidat: The Venus transit of 2012 observed by SDO/HMI
- 17:10 JP Rozelot: Solar metrology (diameter, limb shape, asphericity)
- 17:35 T Dudok de Wit: High resolution solar diameter measurements for PICARD
- 18:00 adjourn
Thursday 26th September
- 09:00 W Schmutz: The future of PMOD/WRC TSI measurements
- 09:25 G Kopp: PICARD Contributions to the 35-Year Total Solar Irradiance Record
- 09:50 M. Meftah: SOVAP/PICARD, a space radiometer to measure the TSI
- 10:15 A Hauchecorne: Solar diameter determination during the June 2012 Venus transit
- 10:40 coffee break
- 11:00 JY Prado/JP Barriot: Determination of the sun diameter from photometer measurements during the November 3, 2012 solar eclipse in North Australia
- 11:25 R Bush: Solar studies with HMI on SDO
- 11:50 R Ikhlef: PICARD sol: results after 28 months of observations
- 12:15 E Rozanov: the solar contribution to future climate and ozone layer changes
- 12:40 Lunch break
- 14:00 D. Salabert: Helioseismology with PICARD
- 14:25 A Irbah: Solar oblateness for SODISM observations
- 14:50 S Turck-Chièze: Prediction of different indicators of the PICARD mission
- 15:15 coffee break
- 15:40 Round table on the scientific exploitation of PICARD data until the end of the mission and beyond and the future of solar observations from space and during astronomical phenomena
- 17:00 adjourn
05/29/2013: PICARD/SODISM and SDO/HMI agreement
Philip H. Scherrer (Stanford University) PI of HMI mission on board SDO and Alain Hauchecorne (LATMOS) PI of PICARD mission, signed a Letter of Intent for scientific and technical cooperation between these two space missions.
05/28/2013: Technological experimentations with PICARD satellite
PICARD International Steering Committee ratified the recommendation of the REDEM Steering Committee not to extend PICARD mission in. Following the PICARD Exploitation Review of November 27 and 28, 2012, CNES proposed to realize in flight experimentations with the PICARD satellite during the phase F. In order to prepare these experimentations, a call for ideas has been issued at the beginning of 2013 to the CNES technical services, as well as ASTRIUM and THALES ALENIA SPACE. 16 propositions have been received and 9 have been selected. 7 propositions are underway until the end of October 2013; they concern:
- the study of the SODISM instrument CCD detector performances,
- the validation of the CORTEX Quantum equipment performances and the functionalities of the S Band interface,
- the analysis of PICARD star tracker performances, as well as the validation of its performances improvement due to the modifications in its software,
- the inspection of PICARD by Mango/PRISMA satellite: a rendez-vous demonstration with a non-cooperative satellite (PICARD) will be performed then the inspection of this satellite by the Swedish satellite Mango/PRISMA.
Other propositions should take place at the beginning of 2014, and should enable to:
- validate the autonomous guiding defined by ISIS for the future missions,
- enable to validate a new command law for the wheels for the future missions.
In addition, CNES endorsed the laboratories demand to acquire, when possible, payload data during these technological operations.
02/2013: The solar oblateness measurement: history of the measurements, objectives and scientific results
(MP4 format 108 Mb)
01/2013: The millionth image of SODISM instrument
Since the launch of PICARD mission (June 15, 2010), SODISM instrument acquired its millionth image in January 2013. This observation has been done at a particular wavelength: the calcium line (Ca II K) in the night-blue part of the solar spectrum. The interest in this observation at such a wavelength (393.37 nm) is that it reveals the regions of the chromosphere and detects the active regions of the Sun (facules and spots). These images are mainly dedicated to the study of the solar activity and enable to measure the differential rotation. The instruments of the space mission PICARD are pursuing their acquisitions. The data exploitation and the scientific activities are continuing...
11/2012: Solar eclipse on November 13, seen by PICARD
Animation of SODISM images acquired during the solar eclipse by the moon at 535 nm wavelength on November 13, 2012.
11/2012: Movies of the Presentations of the scientific PICARD workshop held on April 10th, 2012 at CNES Paris are now available in the Media Gallery!
07/2012: The history of Venus transits
Video presenting the history of Venus transits observed by men from Galileo to PICARD
06/21/2012: Presentations of the scientific PICARD workshop held on April 10th, 2012 at CNES Paris
The workshop presentations are available through its agenda.
06/06/2012: The Picard satellite observed the Venus Transit
Here are the first images of SODISM telescope (at 607 nm) on board PICARD satellite of the Venus Transit (credits CNES/CNRS-LATMOS)
The satellite is rotating around the Earth while keeping focus on the Sun. This would cause a sine wave like pattern to be observed for the path of the object between the satellite and the Sun (Venus of course in this case).
06/05/2012: The Picard satellite will observe the Venus Transit on June 5-6
With the data obtained during the Venus Transit on June 5-6, the Picard satellite will improve our knowledge of the shape of the sun, and provide an accurate measure of the Sun diameter.
Another interest is to test current methods to search the exoplanets by the transit method (variation the light intensity received at the detectors level). Other scientific objectives are targeted as the study of the Venus atmosphere.
From a technical standpoint, the VENUS Transit will help the PSF determination of the SODISM instrument.
05/20/2012: Eclipse flower seen by PICARD
On this image taken by the SODISM instrument on board Cnes' satellite Picard on May 20th, a strange "Moon flower" seems, like the Little Prince's rose, to have grown on our natural satellite limb.
Of course, without atmosphere and liquid water, no flower can grow on the Moon. This beautiful plant was just a group of sun spots that the perspective placed at the limb of the Moon during the partial solar eclipse by the Moon.
Continuously ausculting our star since June 2010, Picard satellite was ideally placed to photograph this partial eclipse.
Note that Picard will also be well placed to observe Venus transit in front of our star on June 6th, the last transit before 2117!
04/10/2012: PICARD Scientific Workshop at CNES headquarters in Paris
This workshop objective is to present the first results of the mission, as well as the instruments in-flight performances. Another objective will be to prepare a Call for "Guest Investigators" and PICARD data use.
The workshop will be held at:
Centre national d'études spatiales
2 place Maurice Quentin
75039 PARIS Cedex 01
For more information and inscription to the workshop, contact Michel Rouzé
03/2012: The enormous Sun spot that produces eruptions
The origin of the solar eruption on the March 7, 2012 is a big sun spot that appeared on March 2 on the border of the Sun. This spot is named AR 1429 by astronomers.
The SODISM telescope of the PICARD satellite captured a set of images at 393 nm wavelength, more particularly between March 6 and 9. Theses images show the evolution of AR 1429 position, which extends on a length equivalent to 8 times the Earth diameter!!!
The different and powerful solar eruptions that took place during this period could have provoked magnetic disturbances in the Earth's environment (especially for satellites). They also are at the origin of magnificent polar aurora, which result from the entry of solar particles in the atmosphere.
06/01/2011: PICARD observes a new partial Sun eclipse
The six images above have been taken on June 1st, 21h59, 22h02, 22h05, 22h07, 22h10 and 22h14 (Universal Time UTC) at the wavelength of 535 nm.
They enable to observe the transition of the Moon between the Earth and the Sun.
Otherwise, scientists pursue their analysis and interpretation work of the enormous volume of data collected.
01/04/2011: PICARD observes the partial Sun eclipse
The four images above have been taken on January 4th, 2011 at 8h25-8h26-8h27 and 8h28 (Universal Time UTC) at the wavelength of 782 nm while the satellite flew over Greenland.
They enable to observe the transition of the Moon between the Earth and the Sun.
The Sun image is gradually shifted from the center of the image, due to the satellite driving principle which points towards the gravity center of the lighted part of the Sun.
From a scientific point of view, the interest of this observation is limited because the eclipse is partial. Nonetheless, by using SOVAP and PREMOS instruments measurements, the consequences of the darkening of the center-border of the Sun on the total and spetral radiation can be studied.
Otherwise, scientists pursue their analysis and interpretation work of the enormous volume of data collected.
11/24/2010: Scientific Mission Center delivery to its operator
The delivery key point (hand over) of PICARD CMS took place on November 23 and 24, 2010, in Brussels with representatives from CNES, which was the prime contractor for this development, from B-USOC which is its operator, from Belpso, which funds the development and the operations and from IASB which hosts it.
The CMS-P was developed by the Belgian company Spacebel.
After the key point, the CMS-P was accepted without reservation by its operator. The operations responsibility, conducted in coordination with the Mission Operations Preparation Group (scientific group) and its maintenance switches from CNES to B-USOC.
These last delivery and responsibility change conclude the passage of PICARD system to routine operation mode.
CNES and B-USOC responsibles working
Bruno Millet PICARD system responsible
with Dominique Fonteyn, Belspo Director
11/18/2010: Definitive opening of SOVAP right shutter
SOVAP instrument was victim, since July 26, of a dysfunction of the entry shutter of the right cavity. Faced with this issue, the instrument responsibles decided to let this shutter permanently open; however the different commands sent to this objective failed until November 18 when the opening manoeuvre succeeded. The shutter will now stay open until the end of the mission, enabling the instrument to ensure its scientific mission.
11/12/2010: Entry in eclipses period
The 6h00-18h00 orbit choice is dedicated to minimize the eclipses periods during the year, interrupting the continuous observation of the Sun. This period is thus limited to a few weeks around the winter solstice.
It begun on November 12 and the eclipses duration will gradually increase to reach the value of 20 mn on December 20.
The eclipse entry and exit go with a period during which the Sun is seen through the atmosphere, which refracts its rays: the Sun image is thus distorted and seen in a different direction than the real one.
During this absorption period, the satellite stay guided as long as possible by its solar ecartometry sensor, in the Sun direction. The scientific instruments continue the acquisition of measurements in order for SODISM, to study the distortion of the limb through the atmosphere, and for the radiometers, to analyse the impact of the atmosphere on the spectral repartition of the solar radiation.
At the beginning of the eclipse, the pointing is realised by star sensors.
At the end of the eclipse, the satellite stay pointed in the theoretical direction of the Sun until the solar ecartometry sensor receives enough solar flux to enable a correct pointing. This period is used by SODISM to try to evaluate the impact of the temperature variation of its front part (it was notably cooled during the eclipse) on the instrument metrology.
The graphic above represents the variation (expressed in arc second) between the direction aimed by the satellite and the direction of the Sun. Two eclipses periods can be observed with an important variation during the beginning and the end of the eclipse (effect of the switch between the star sensor and the solar ecartometry sensor) and a decreased pointing performance when the satellite is driven by the star sensors instead of the solar ecartometry sensor.
10/15/2010: PICARD declared ready for duty
The in-flight commissioning operations successfully ended on October 8.
The system was declared ready to begin the exploitation phase after the in-flight commissioning review.
The Calibration Validation phase, dedicated to the last tuning to reach the system ultimate performances thus begins.
10/07/2010: New images of the Sun taken by SODISM instrument
SODISM instrument continu its regular acquisition of images of the Sun (one each minute). The 5 images below have been taken at 5 wavelength of SODISM instrument SODISM. They have been obtained after application of a processing to correct the main optical and radiometric defaults of the raw images.
Image at 535 nm taken on 04/09/2010 at 13h31
Image at 607 nm taken on 02/09/2010 at 04h04
Image at 782 nm taken on 03/09/2010 at 09h04
Image at 215 nm taken on 22/09/2010 at 03h53
Image at 393 nm taken on 22/09/2010 at 04h23
The images at 535 nm, 607 nm and 782 nm are mainly used to measure the Sun's diameter and the study of its shape.
The images at 215 nm and 393 nm are mainly used to study the solar activity.
All these images enable to visualise several sun spots. These images confirm the increase of the solar activity.
| High resolution AVI format ~26,5 Mb|
High resolution MOV format ~23 Mb
Low resolution AVI format ~2,4 Mb
Low resolution MOV format ~2,7 Mb
This video is a series of images taken at the wavelength of 393 nm between August 5 and 31, 2010. It shows a nearly complete rotation of the Sun.
These images have been obtained after processing to correct the main defaults of the instrument.
10/06/2010: First stellar pointing
During the in-flight commissioning operations, PICARD successfully realised its first stellar pointing sequence.
During this particular operation, the satellite doesn't point towards the Sun, but towards a couple of stars which angular distance is near the value of the solar diameter, located in the opposit direction from the Sun. The image taken by SODISM serves to compare the distance between the stars as measured by the instrument to the distance foretold by Hipparcos catalogue, to calibrate, in the absolute, the measurement function of SODISM.
07/27/2010: First image of the Sun taken by SODISM instrument on July 22, 2010 at 16h12.
It is a raw image, level L0, thus obtained before processing, at 607 nm wavelength in a very narrow band of 0.5 nm width.
Several solar spots can be seen in the lower left part. These spots appear at high solar lattitude then move slowly towards the solar equator, their number increasing with the solar activity.
The 607 nm wavelength enables to measure the shape (diameter, flatening) of the solar disk at the photosphere level.
SODISM also has filters at 215, 393, 535 and 782 nm, enabling to study the active regions (sun spots, facula) as well as the Sun internal structure interne (heliosismology).
The CCD has 4 Millions pixels.
PICARD payload is also composed of 2 radiometers measuring the total and spectral solar irradiance. PICARD is a solar metrology mission, not an imaging mission. The wealth of the mission is in the continuous observation of the Sun during several years to get very precise measurements of characteristics such as the diameter and the emitted power, their variations (with a precision of about 10-6) and their relations during all the increasing phase of the 11 years solar cycle.
07/02/2010: End of the first operations to bring the payload to operational configuration
The 3 instruments are now functioning, all their parameters are nominals.
SODISM is in decontamination mode, at the mean temperature of 25°C; dark current images are regularly acquired.
All the system componants (satellite and payload, control center, network, mission center) are fonctioning nominally.