09/2015: Presentations at the Solar Metrology, Needs and Methods II symposium
A year after the first one in Paris, CNES, LATMOS and STCE, Belgium’s Solar-Terrestrial Centre of Excellence, organized the second Solar Metrology, Needs and Methods symposium, at the Belgian Royal Observatory in Brussels, from 21 to 23 September.
The symposium’s objective was to review recent advances in these two domains, to analyse the capabilities and limitations of current ground-based and space-based observation systems, and to discuss the major challenges facing future missions.
Presentations given at the symposium.
07-09/10/2014: Solar Metrology, Needs and Methods symposium in Paris
CNES and LATMOS are organizing a symposium on Solar Metrology, Needs and Methods from 7 to 9 October in Paris.
The objective of this symposium is to bring together research scientists working in the fields of solar physics, metrology and modelling to look at available observations of solar parameters (total and spectral irradiance, diameter and figure of the Sun, helioseismology, etc.) obtained from current space missions (Picard, SOHO, SDO) in the light of solar model requirements.
The aim is to assess if these observations are adequate in terms of methods and precision to constrain solar models, to determine whether certain parameters are lacking and to discuss the direction to be taken to improve them for future solar missions.
04/04/2014 : Dernière télécommande envoyée au satellite PICARD
La dernière télécommande a été envoyée au satellite PICARD aujourd'hui lors du passage du satellite à 10h26, heure de Toulouse, en visibilité de la Station de Kourou.
Une présentation exposant la mission et ses résultats scientifique a ensuite eu lieu au Centre Spatial de Toulouse.
- Christine Fallet : Les expérimentations fin de vie autour du sous système de contrôle d'attitude et d'orbite
03/11/2013: Hybrid solar eclipse on 3 November
Observations of the eclipse at several wavelengths (393.37, 535.7 and 607.1 nm)
It was the ninth solar eclipse of this century and the second of the year. The Moon played with the Sun to produce an extremely rare hybrid, annular eclipse to begin with, and then a total eclipse. The eclipse was visible from the American and African continents. The Picard satellite’s telescope was able to capture pictures of the event, observing it at several wavelengths (393.37, 535.7 and 607.1 nm). The Sun is displaying signs of renewed activity, with dark sunspots and faculae, and a big solar flare on 5 November.
11/2013: SODISM-II Ca II images at 393 nm acquired from Calern during summer 2012 and 2013
SODISM-II images acquired between April and October 2012 (left)
and April and September 2013 (right)
The ground component of the Picard mission is operational since May 2011. Images are acquired in the Ca II absorption line at 393 nm, revealing details of activity in the Sun’s chromosphere since this date (data available from the mission’s PI, Alain Hauchecorne).
See the full article on the Côte d'Azur Observatory website.
21/10/2013 : Données PICARD disponibles pour la communauté scientifique
Picard data are now available to the scientific community via the http://picard.busoc.be website:
For more specific searches of SODISM data (level 1), the SODISM catalogue is on line on the website (http://picso.busoc.be).
A "Help" button on the PICSO home page links to a short page with help for using the search tool (and obtaining selected data).
This website can be accessed with the same username (GISGENPI) and password (4LdL!v;8).
In the event of a problem or for further information, contact Michel Rouzé.
For science-related questions about the mission, contact the PI Alain Hauchecorne
25/09-26/09/2013: Picard science workshop at CNES Head Office
The workshop brought together Picard Principal Investigators, Co-Investigators and Guest Investigators to present the latest science results, address certain important technical issues regarding exploitation of science data and identify possible areas of cooperation between the research laboratories, etc.
Some of the presentations can be viewed in Meetings.
29/05/2013: Picard/SODISM and SDO/HMI letter of intent
Philip H. Scherrer (Stanford University), PI of the HMI mission on SDO, and Alain Hauchecorne (LATMOS), PI of the Picard mission, signed a letter of intent to cooperate on science and technology work for these two space missions.
28/05/2013: Technology experiments with the Picard satellite
The Picard International Steering Committee endorsed the recommendation of the REDEM Steering Committee not to extend the Picard mission in 2013. Following the Picard Exploitation Review of 27 and 28 November 2012, CNES proposed to conduct in-flight experiments on Picard during phase F of the mission. To ready these experiments, a call for ideas was issued early in 2013 to CNES’s technical departments and to Astrium and Thales Alenia Space. Sixteen proposals were received, from which nine were selected. Seven are still ongoing until end October:
- performance assessment of the SODISM instrument’s CCD detector
- performance validation of the CORTEX Quantum device and the features of the S-band interface
- performance analysis of Picard’s star tracker and validation of performance enhancements due to changes to its software
- inspection of Picard by the Mango/PRISMA satellite: operations to rendezvous with a non-cooperative satellite (Picard) will be demonstrated and it will then be inspected by the Swedish Mango/PRISMA satellite
Other proposals are expected to be implemented early in 2014 to:
- validate the autonomous guidance defined by ISIS for future missions
- enable validation of a new wheel command law for future missions
CNES has also granted the laboratories’ request to acquire data from the payload during these technology operations wherever possible.
02/2013: Measurement of solar flattening: history of measurements, science goals and results
(MP4 format - 108 Mb, in French)
01/2013 : La millionième image de l'instrument SODISM
Depuis le lancement de la mission spatiale PICARD (15 juin 2010), l'instrument SODISM a acquis sa millionième image en janvier 2013. Cette observation a été réalisée à une longueur d'onde bien particulière : la raie du calcium (Ca II K) dans la partie bleue-nuit du spectre solaire. L'intérêt de cette observation à cette longueur d'onde (393,37 nm) est qu'elle révèle les régions de la chromosphère, et détecte les régions actives du Soleil (facules et tâches). Ces images sont principalement destinées à l'étude de l'activité solaire et permettent en particulier la mesure de la rotation différentielle. Les instruments de la mission spatiale PICARD continuent leurs acquisitions. L'exploitation des données et les activités scientifiques se poursuivent...
11/2012: Solar eclipse of 13 November viewed by Picard
Animation of SODISM images acquired of the eclipse of the Sun by the Moon at the wavelength of 535 nm on 13 November 2012.
11/2012: Films of presentations at the Picard Science Workshop of 10 April 2012 at CNES in Paris are now viewable from the Multimedia Gallery page.
07/2012: History of Venus transits
Video about the history of Venus transits in front of the Sun seen by man from Galileo to Picard.
21/06/2012: Presentations at the Picard Science Workshop of 10 April 2012 at CNES in Paris
The Workshop presentations can be accessed via the diary.
06/06/2012: Picard satellite observes Venus transit
Here are the first images from the SODISM telescope (at 607 nm) on the Picard satellite of the Venus transit (credits: CNES/CNRS-LATMOS)
The satellite is orbiting Earth but stays pointed at the Sun, giving the impression of a sinusoidal motion observed when an object (here, Venus) passes between the satellite and the Sun.
05/06/2012: Picard satellite to observe Venus transit on night of 5-6 June
With the data it is set to acquire on 5 and 6 June, Picard will tell us more about the figure of the Sun and enable us to measure its diameter very precisely.
This event will also serve to test current transit methods for detecting exoplanets, which look for a dip in brightness when they pass in front of their star. Other science goals include studying Venus’ atmosphere.
From a technical standpoint, the transit will help to highlight the SODISM instrument’s point spread function (PSF).
20/05/2012: Picard sees eclipse ‘flower’
In this image taken by the SODISM instrument on CNES’s Picard satellite on 20 May, a strange flower-like form, reminiscent of the rose in Antoine de Saint-Exupéry’s The Little Prince, appears to be growing from the limb of the Moon.
Obviously, as the Moon has no atmosphere or liquid water, flowers can’t grow there. This beautiful ‘plant’ is in fact a cluster of sunspots on the Moon’s limb from the perspective of a partial eclipse of the Sun.
Probing our star since June 2010, Picard was ideally placed to capture this partial eclipse.
Picard will be equally well placed to see the transit of Venus in front of our star on 6 June, the last time such an event will occur before 2117!
10/04/2012: Picard Science Workshop at CNES Head Office in Paris
The aim of this workshop is to present the first results from the mission and detail the in-flight performance of the instruments. It will also be looking to prepare a call for investigations and utilization of Picard data.
The workshop will take place at:
Centre national d'études spatiales
2 place Maurice Quentin
75039 PARIS Cedex 01
For further information and to register for the workshop, contact Michel Rouzé.
03/2012: Huge sunspot produces flares
The solar flare of 7 March came from an enormous sunspot that appeared at the edge of the Sun on 2 March. This sunspot has been recorded as AR 1429 by astronomers.
The SODISM telescope on the Picard satellite acquired a series of images at the wavelength of 393 nm, in particular between 6 and 9 March. These images show the movement of AR 1429, which spans the equivalent of 8 times Earth’s diameter!
The powerful solar flares during this period could have generated magnetic perturbations in Earth’s environment, especially for satellites. Such phenomena are also what cause the magnificent polar aurorae, when solar particles enter the atmosphere.
01/06/2011: Picard observes new partial solar eclipse
These six views were acquired on 1 June at 21:59, 22:02, 22:05, 22:07, 22:10 and 22:14 (UTC) at the wavelength of 535 nm.
They show the transit of the Moon between the Earth and Sun.
Meanwhile, the science teams are continuing to sift through and interpret the masses of data collected.
04/01/2011: Picard observes partial solar eclipse
The four views above were taken on 4 January 2011 at 8:25, 8:26, 8:27 and 8:28 (UTC) at the wavelength of 782 nm as the satellite was flying over the south of Greenland.
They show the Moon’s transit between the Earth and the Sun.
The image of the Sun is gradually offset from the centre of the image due to the satellite’s guidance principle, which points it towards the centre of gravity of the luminous part of the disk.
The science value of this observation is limited, as the eclipse is only partial. However, measurements from the SOVAP and PREMOS instruments will enable us to study the consequences of the darkening of the centre-edge of the Sun on total and spectral irradiance.
Meanwhile, the science teams are continuing to sift through and interpret the masses of data collected.
24/11/2010: Science Mission Centre delivered to operator
The handover of the Picard Science Mission Centre (CMS-P) took place on 23 and 24 November in Brussels with representatives from CNES, which was prime contractor for the centre’s development, the operator B-USOC, BELSPO (the Belgian Science Policy Office), which is funding development and operations, and IASB, the Royal Belgian Institute for Space Aeronomy, which is hosting the centre.
CMS-P was developed by Belgian firm Spacebel.
At the end of the handover, CMS-P was accepted with no reservations by the operator. Responsibility for operating the centre, in coordination with the Mission Operations Preparation Group (science group), and for maintaining it is therefore transferred from CNES to B-USOC.
This handover concludes the switch to routine operation of the Picard system.
The CNES manager and the B-USOC manager at work
Bruno Millet, PICARD systeme manager
with Dominique Fonteyn,
18/11/2010: SOVAP’s right shutter opening confirmed
The SOVAP instrument had been experiencing a malfunction of the shutter mechanism in its right cavity since 26 July. As a result, the instrument PIs took the decision to leave the shutter permanently open, but attempts to send commands to this effect had failed until the manoeuvre was finally successful on 18 November. The shutter will now remain open until the end of the mission to allow the instrument to accomplish its science mission.
Film explaining how mission teams went about opening the shutter (in French)
Flv format, viewable in VLC
12/11/2010 : Entrée en période d'éclipses
The spacecraft’s 6:00-18:00 dawn-to-dusk orbit is designed to reduce eclipse periods during the year that preclude continuous observation of the Sun to a minimum. This orbit limits eclipses to a few weeks around the winter solstice.
This period started on 12 November and the length of eclipses will progressively increase, reaching a maximum of 20 minutes on 20 December.
There is also a period at the start and end of each eclipse when the Sun is viewed through the atmosphere, which causes its rays to refract. As a result, the image of the Sun is both distorted and viewed in a different direction to its real direction.
During this absorption period, the satellite is guided for as long as possible by its Sun tracker, in the direction seen from the Sun. The scientific instruments continue acquiring measurements designed 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 distribution of solar irradiance.
As soon as an eclipse starts, pointing is accomplished by the star trackers.
At the end of an eclipse, the satellite remains pointed in the theoretical direction of the Sun until the Sun tracker receives enough solar flux to allow correct pointing. SODISM takes advantage of this lapse of time to attempt to gauge the impact of any variation in the temperature of the front part of the instrument (which cools considerably during an eclipse) on the instrument’s metrology.
Le graphe ci-dessus représente l'écart (exprimé en secondes d'arc) entre la direction visée par le satellite et la direction du soleil. On observe 2 passages en éclipse, avec un écart important lors de l'entrée et de la sortie en éclipse (effet du basculement entre senseur stellaire et senseur d'écartométrie solaire) et une performance de pointage dégradée lorsque le satellite est piloté grâce aux senseurs stellaires et non plus grâce au senseur d'écartométrie solaire.
15/10/2010 : PICARD déclaré bon pour le service
In-orbit checkout operations were successfully completed on 8 October.
The system was declared ready to begin its operations phase after the in-orbit checkout review.
The Calibration/Validation phase to fine-tune the instruments and obtain optimum system performance is therefore now underway.
07/10/2010: New images of Sun from SODISM instrument
The SODISM instrument is continuing to acquire regular images—one per minute—of the Sun. The five images below were acquired at the instrument’s five operational wavelengths and then processed to correct the raw imagery for its main optical and radiometric defects.
535-nm image taken on 04/09/2010 at 13:31
607-nm image taken on 02/09/2010 at 04:04
782-nm taken on 03/09/2010 at 09:04
215-nm image taken on 22/09/2010 at 03:53
393-nm image taken on 22/09/2010 at 04:23
Images at 535 nm, 607 nm and 782 nm are designed chiefly to measure the Sun’s diameter and study its figure.
Images at 215 nm and 393 nm are designed chiefly to study solar activity.
Viewed together, these images show several sunspots and confirm that solar activity is picking up.
This video is a series of images taken at the wavelength of 393 nm between 5 and 31 August. It shows an almost complete rotation of the Sun.
The images are obtained after digital processing to correct the main instrument defects.
See more on the CNES blog.
06/10/2010: First star pointing
As part of in-orbit checkout operations, Picard has successfully completed its first star pointing sequence.
During this specific operation, instead of viewing the Sun the satellite is pointed at a pair of stars whose angular distance is close to the value of the solar diameter and in a direction opposite the Sun. The image acquired by SODISM is used to compare the distance between stars as measured by the instrument and that predicted in the Hipparcos catalogue, in order to calibrate SODISM’s measuring function absolutely.
27/07/2010: First view of Sun acquired by SODISM instrument on 22 July at 16:12.
This is a raw, level 0 image obtained before any processing, at the wavelength of 607 nm and in a very narrow band of 0.5 nm.
Several sunspots can be made out bottom left. These spots appear at high solar latitudes and then slowly migrate towards the equator, their number increasing as solar activity grows in intensity.
The 607-nm wavelength enables the figure (diameter and oblateness) of the solar disk to be measured in the photosphere.
SODISM also has filters at 215, 393, 535 and 782 nm that make it possible to study active regions (sunspots and faculae) and the Sun’s interior structure (helioseismology).
The CCD has four million pixels.
Picard’s payload also includes two radiometers for measuring total and spectral solar irradiance. Picard is a solar metrology mission, not an imaging mission. Its value lies in its ability to continuously survey the Sun for several years to obtain very precise measurements of features like its diameter and emitted power, how they vary (with a precision on the order of 10-6) and how they interact throughout the long ascending phase of the 11-year solar cycle.
02/07/2010 : Fin des premières opérations de mise en configuration opérationnelle de la charge utile
The three instruments are now operative and all parameters are nominal.
SODISM is in decontamination mode, at an average temperature of 25°C, and dark-current images are being regularly acquired.
All system components—satellite and payload, control centre, network and mission centre—are nominal.