Trainees 2018 - ESAC Trainees

2018 ESAC TRAINEE PROJECTS

Below are the projects offered in 2018

1. TRIGGERING XMM-NEWTON TARGET OF OPPORTUNITY OBSERVATIONS WITH SWIFT

ESAC supervisor(s): Norbert Schartel, Maria Santos-Lleo and Richard Saxton

XMM-Newton is an ESA space observatory that collects X-rays from astronomical sources. It carries three high throughput X-ray telescopes with an unprecedented effective area. Each telescope has an X-ray CCD camera, comprising the European Photon Imaging Camera (EPIC). In addition XMM-Newton is also equipped with two Reflection Grating Spectrometers and an Optical Monitor for simultaneous X-ray imaging, spectroscopy and UV/optical measurements. The large collecting area and spectral capabilities combine with an ability to make long uninterrupted exposures making XMM-Newton an ideally suited observatory to provide highly sensitive, high spectral resolution, long and continuous X-ray observations.

Many astronomical sources are extremely variable in X-rays, very often in an unpredictable way and often different source fluxes correspond to different physical states of the source. After 16 years of successful operations of XMM-Newton, more and more astronomers are requesting to observe sources in a specific state, i.e. at an specific source flux. Once a source reaches the aimed specific flux and hence state, deep follow-up observations allow science which is not accessible in other states. Knowing a source state early enough is then key to request, prepare and schedule the observations. The NASA Swift mission is ideally suited for this task. Designed to study gamma-ray-bursts, when not observing one of those events, Swift monitors the behaviour of X-ray sources in the sky. Swift observations can then be used to reveal sources in a specific flux or spectral state and trigger XMM-Newton follow-up, Target of Opportunity (ToO), observations. Whereas Swift observations can be analysed with a reasonable amount of work, automated tools to systematically analyse Swift observations are not available in the XMM-Newton Science Operations Centre. Such tool would allow to optimize the operational as well as the scientific work and allow the efficient trigger of the XMM-Newton ToO.

The aim of the project was to help gain experience in scientific research and to develop a script which analyses the Swift observations in an automated way and compares the obtained fluxes with known source fluxes based on the already established XMM-Newton and ROSAT catalogues.

2. EXTENSION AND EXPLOITATION OF HIGH-ENERGY UPPER LIMIT TOOLS

ESAC supervisor(s): Richard Saxton and Peter Kretschmar

In a previous trainee project web-based tools were produced to find and display the flux of X-rays and Gamma-rays coming from stars and galaxies. The system is complete for the XMM-Newton, Integral and ROSAT satellites and provides astronomers with the possibility to quickly look at the variations in light from celestial objects and find exciting new transients. This project aimed to extend the system to access data from other X-ray satellites such as Chandra, Swift and EXOSAT and introduce ultraviolet images taken by GALEX and the optical monitors on board XMM-Newton and Swift. The system was used then to look for unusual ultraviolet and X-ray variability in a sample of galaxies.

This project was designed to provide a practical view of UV and X-ray astronomy, database programming and a client/server javascript and python programming.

3. X-RAY INVESTIGATIONS OF THE UNIQUE "BURSTING PULSAR

ESAC supervisor(s): Felix Fuerst, Celia Sanchez Fernandez and Peter Kretschmar

Neutron stars are the compact remnants of dead stars and possess densities and magnetic field orders of magnitudes in excess of what is available in the lab. When they are located in a binary system with another star, they can accrete material from that star, thereby producing copious amounts of X-rays. Studying these accreting neutron stars in X-rays allows to study their composition, magnetic field, and accretion geometry and help us to understand the formation of neutron stars as the end-product of stellar evolution better.

One of the most unique accreting neutron stars is the so-called "Bursting Pulsar", GRO J1744-28. It shows regular pulsations with a frequency of about 2.2Hz, but also irregular thermo-nuclear bursts from accreted material on its surface. Furthermore, the hard X-ray spectrum revealed direct evidence for its magnetic field, through the study of so-called cyclotron resonant scattering features. This combination of observables makes the Bursting Pulsar stand out among its peers and allows a unique approach to investigate accretion physics as well as the properties of the neutron star.

This project, analysed data of GRO J1744 taken with different X-ray satellites like XMM-Newton, INTEGRAL, and NuSTAR. By analysing the soft and hard X-ray spectrum simultaneously, it was possible to constrain the flow of matter around the neutron star, measure its magnetic field, and study the physical conditions within the accretion column (e.g., infer the plasma temperature).

Is was a great way to learn about X-ray astrophysics and the analysis methods commonly used. The goal of the project was to summarise the results in a scientific manuscript.

The successful candidate had opportunity to learn to use specialised software to perform X-ray data analysis (X-Spec, ISIS), perform X-ray spectral and timing data analysis using this software, apply statistical methods to find significances of the detected features, perform a physical interpretation of the data (in close collaboration with the mentors) and write a scientific article about these data and publish the results.

4. X-RAY OBSERVATIONS OF NEARBY ACTIVE GALAXIES WITH XMM-NEWTON

ESAC supervisor(s): Jacobo Ebrero and Maria Santos-Lleo

Active galactic nuclei (AGN) are powered by accretion of matter onto the supermassive black hole that resides in their centre. Their large bolometric output is powerful enough to drive ionized winds into the interstellar medium of the host galaxy and even into the intergalactic medium. The enormous amounts of matter and energy thus injected may affect the evolution of the central black hole and the galaxy in a process called cosmic feedback. These ionized outflows are detected through the absorption lines of ionized species typically blueshifted with respect to the rest frame of the source in the X-ray/UV continuum of the AGN (hence they are also known as warm absorbers). In spite of their potential importance, the origin, location, and impact of these winds are still a matter of debate and a hot topic in modern extragalactic astrophysics.

This project involved the analysis and study of X-ray data of two bright nearby AGN obtained with the ESA's X-ray observatory XMM-Newton. X-rays provide a unique view of the violent processes that take place in the innermost regions of AGN and therefore they are essential to understand their physics. The two active galaxies to be studied have been recently observed and the full scientific potential of these observations has not been fully exploited yet. The goal of the project was to reduce the data, and extract the X-ray spectra using two different instruments onboard XMM-Newton: the Reflection Grating Spectrometer (RGS), which produces high-resolution spectra at soft X-ray energies, and the EPIC-pn camera, which can be used to extract medium-resolution spectra in a wider energy band. These spectra were analyzed using specific X-ray spectral fitting software in order to obtain a global picture of the physical phenomena that are taking place in these AGN.

The project was intened to provide a basic experience in scientific research and X-ray data analysis and a general understanding of the physical processes in an AGN at high energies.

5. CODE ANALYSIS FOR CASSINI VIMS DATA AND JUICE

ESAC supervisor(s): Anezina Solomonidou, Rafael Andres, Nicolas Altobelli

The project was focused on the analysis of two IDL codes that need improvement of their usability, analysis of their robustness and, in the JUICE case, a preliminary assessment of a migration to Python, for improved performance and easier long term maintenance.

Cassini-VIMS radiative transfer code

Titan, Saturn’s largest satellite explored by the Cassini–Huygens mission since 2004, is a complex world in which methane plays an important role. Information on the origin and evolution of the satellite relies on a good understanding of the origin and maintenance of methane in Titan’s atmosphere and the methanological cycle with all the processes and exchanges involved between the atmosphere, the surface and the interior. In such studies, some information on these mechanisms is becoming available today, in particular by spectro-imaging techniques from the ground and space, but a meaningful analysis of these data demands a precise knowledge of the methane (CH4) opacity on Titan. Many attempts have been made to assess the absorption due to the isotopologues of methane. The most recent spectroscopic results are the end-product of laboratory attempts to create accurate linelists of methane coefficients. We used these data lists in a modular radiative transfer model capable of line-by-line as well as correlated-k calculations for planetary applications, in particular to model the data taken by the Cassini Visual and Infrared Mapping Spectrometer (VIMS).

Juice science opportunity pipeline

The JUICE science opportunity pipeline aims at finding the opportunities of specific science campaigns for a given trajectory. The code is written in IDL, including the NAIF-JPL SPICE libraries, MySQL and ssh scripts. The code is being used by the Juice Science Working Groups in their work of trajectory segmentation, by generating all geometrical and science model related inputs displayed in a web environment to help the mission segmentation in a collaborative environment.

The project required from the trainee to run the codes to understand how they are used, to comment on the radiative transfer code, and make it more user-friendly (possibly including adding new functionalities) and to analyse the feasibility to migrate the JUICE code to Python; this included the production of core librairies, to replace existing ones, with well defined and documented interfaces to be part of a bigger system and regression/integration testing with other system modules.

6. PLANNING SIMULATOR WITH GPU

ESAC supervisor(s): David Frew, Federico Nespoli, Carlos Muniz

MAPPS is an operational software tool that has been developed by ESA. MAPPS has been successfully used in a number of past and ongoing ESA Solar System missions.

The simulator is responsible for generating the required outputs of the Science Planning processes, based on given input data, the mission specific configuration data and any operator inputs, ensuring that the outputs are verified and are guaranteed to be free of conflicts. The simulator will allow the execution of additional tasks, which can be considered as auxiliary tasks supporting the overall Science Planning processes.

This internship offered the opportunity to develop their analytical and design skills while carrying out the feasibility study of an innovative engine to support the spacecraft dynamics and behavioural simulation. This new engine will be based on massive parallel computation using GPUs.

The internship covered gathering of the system requirements, extraction of the algorithm from the existing serial code, preliminary feasibility study on a small subset of the simulator functionalities, identification of the best technologies and the validation of the design through the development of a prototype. The student also had access to a reference simulator to validate the prototype. The feasibility study was carried out in collaboration with the actual development team.

7. MODELLING AND ANALYSIS OF THE MICROSCOPIC PROPERTIES OF COMETARY DUST USING THE ROSETTA/MIDAS DATASET

ESAC supervisor(s): Richard Moissl and Mark Bentley

The project was focused on the analysis of data returned by the MIDAS atomic force microscope which flew onboard the Rosetta orbiter to comet 67P/Churyumov–Gerasimenko. The project was designed as two related topics of investigation, either of which to be considered, depending on the strength of the applicant.

Some of the fundamental properties of cometary nuclei (for example, thermal conductivity, heat flow, and the ice sublimation rate) are governed, to a large degree, by the microscopic properties of the solid particles forming the volatile-poor upper layers. The properties of this dust were studied by various instruments onboard the Rosetta orbiter and Philae lander, but only the atomic force microscope (AFM) was in a position to study the microscopic properties.

1. Particle shape description and bulk property modelling

As well the raw images, the MIDAS dataset in the Planetary Science Archive will soon contain a particle catalogue that identifies cometary particles and gives a basic description of their location on the collection target and their size. This project addressed the description of the complex shape found for the micrometer-sized dust at comet 67P. A variety of metrics are available to describe complex particle shapes are are used, for example, in various industrial processes. This project was aimed to develop good shape descriptors and apply them to characterise the particles detected by MIDAS. After quantifying the shapes of the dust particles it becomes possible to compare with theoretical predictions and reference materials, and to extrapolate to the bulk properties of a material comprising a large numbers of such particles.

The student was required to familiarise themselves with the MIDAS dataset in the Planetary Science Archive, the literature on particle shape descriptors and derive particle shape descriptors from MIDAS data and as a result to perform a parameter study showing how the shape and roughness of particles affect bulk properties, showing where the data from comet 67P fit within this framework.

2. Discrete Element Modelling (DEM) of cometary dust particles

Another approach to understanding the effect of particle shape and roughness on bulk material properties is the Discrete Element Method, in which the dynamics of granular media under various conditions was simulated computationally. Existing open source codes (for example LIGGGHTS) could be used “out of the box” for initial studies. One important question was the collection process of dust on MIDAS targets. To investigate this process numerical aggregates of particles bonded by cohesive forces would be generated and their resulting fragmentation, sticking or disruption on impact with a target studied. The outcome could then be compared with real MIDAS data to understand how strongly the initial particle structure was changed upon impact. A more comprehensive study would modify the contact rules between particles to account for surface roughness (as determined from MIDAS data). This relates to the long-standing issue in modelling cometary activity: how does gas drag overcome the strong particle-particle cohesive forces to eject dust particles. A simulated tensile strength measurement would be performed on a sample of such rough, cohesive particles to evaluate how important these parameters are.

The student would be required to familiarise themselves with the MIDAS dataset in the Planetary Science Archive, with Discrete Element Modelling, use DEM to simulate the impact of cohesive aggregates at speeds similar to those found at comet 67P and study the shape, spatial distribution and other properties of the remaining material and and perform a parameter study showing how the shape and roughness of particles affect bulk properties, showing where the data from comet 67P fit within this framework.

8. FLASHES (FLEXIBLE ALERT SYSTEM FOR HIGH ENERGY SOURCES)

ESAC supervisor(s): Emilio Salazar, Celia Sanchez, Eva Laplace (Tübingen University) and Peter Kretschmar

In previous years a succesful trainee project created the Be X-ray Binary and Black Hole Activity Monitors at ESAC. These tools automatically obtain data from X-ray monitors and indicate if given sources seem to be active. They have proven to be helpful for the scientific comunity, on occasion triggering observations with targeted telescopes. But there are further types of transient or strongly time variable sources not yet covered by these monitor tools, e.g., neutron stars in Low Mass X-Ray Binary (LMXB) systems.

Instead of creating more instances of similar tools, based on the same basic funtionalities, the project FLASHES was foreseen to create an even more generic application, with data display configurable for different source classes handled by a common tool set in the background. More advanced web interfaces and alert mechanisms via mobile phones could also be investigated.

The project focused on performing the systematic software development, extending and improving the existing code base. Statistical methods, including data mining, was used to distinguish between real variability and measurement noise. The project included a training on methods and approaches provided by the tutors. As an outcome the project left a tool used and appreciated by professional astronomers around the world.

9. CONVOLUTIONAL NEURAL NETS AND A GALAXY CLUSTER ZOO

ESAC supervisor(s): Maggie Lieu, Bruno Altieri, Sarah Kendrew (STSci, Baltimore), Ivan Valtchanov

Galaxy clusters are the largest virialised systems in the observable Universe and constitute one of the four important methods to probe cosmology. Whilst their detection can be made in various wavelengths, the only true confirmation of cluster comes from the presence of Bremsstrahlung emission. The hot gas within clusters emits strongly in X-ray wavelengths, none the less, typically only 10’s of photons ever reach our detectors! The confirmation of a cluster detection is typically done by eye, a slow and inefficient process. The uncertainties resulting from such a process is impossible to model and makes the selection function of clusters very messy.

The goal of this project was to develop a new approach to the problem. In the 1st 3 months of this project the traineehad to familiarise themselves with multi-wavelength observations of clusters and build a citizen science project to identify and classify galaxy clusters. The results from the public’s identified systems could then be used a training set for a machine learning algorithm to classify clusters and the task for the remaining 3 months was to develop such an algorithm.

10. GAIA: DESIGN A TOY MODEL OF GLOBAL ASTROMETRY IN PYTHON

ESAC supervisor(s): Alex Bombrun, Jose Hernandez and Uwe Lammers

ESAC is responsible for developing and running AGIS, the software that computes the global astrometric parameters for the Gaia mission. The design and validation of Gaia global astrometric mission requires to be able to run simulations that include complex calibration issues. The current state of the art is AgisLab. This code is proprietary of DPAC, the scientific consortium processing the Gaia data and responsible for the publication of the final star catalogue. This code requires complex configuration and is very tied to Gaia data model. AgisLab was designed in order to be able to run scaled down simulations with some unrealistic instrument size but preserving the final astrometric errors. However AgisLab is strongly tied to Gaia’s complex data model and data processing. One can go some steps further and simplify significantly the focal plane, the satellite orbit and the physic itself.

The project was aimed to start an open source project in Python inspired from AgisLab that could do some basic simulations of global astrometry in a Jupyter Notebook reusing as much as possible existing libraries such as SciPy and Pandas.The project was divided in different parts. The first part was to design a scanner that generate simulated observations with a simple nominal scanning law. The second part was to do a fit of the underlying least square problem and analyse the solution.

The project was designed to help to understand the basic principle of global astrometry, ensuring a few months of immersion in one of the most challenging astronomical mission and an experience in model prototyping and data analysis in the Python environment.

11. 3D MAPS OF NEARBY STAR FORMING REGIONS WITH GAIA

ESAC supervisor(s): Hector Canovas, Alcione Mora, Uwe Lammers

Stars are born in gigantic gaseous clouds typically containing a few hundreds of young stars. As these stars evolve they accrete their surrounding gas and eventually form a protoplanetary disk around them. These disks are the birthplaces of planets, and therefore studying their evolution and environment is crucial to understand the (complex) process of planet formation.

In the Earth neighborhood (within 300 pc) there are a few five star forming clouds that, given their youth (less than 10 Myr) are ideal laboratories to study early stellar evolution and planet formation. The 3D structure of these star forming regions remains mostly unknown: we don’t know yet how deep these clouds are, and little is known about the distribution in volume of the stars in the clouds. GAIA will change this as it is accurately measuring the position and distance of millions of stars.

This project required from the trainee to use the GAIA DR2 to construct a 3D map of different star forming regions. Once this was achieved, the map was combined with complementary data such as protoplanetary disk and stellar properties (e.g., disk masses, stellar luminosities) to obtain a detailed picture of the star forming regions.

The project gave opportunity to explore large astronomical databases to retrieve the coordinates and distances of the individual stars, generate 3D maps with the spatial distribution of the stars in the clouds and apply additional layers of information (e.g., stellar and protoplanetary disk properties).

12. SPACE SURVEILLANCE AND TRACKING SEGMENT: SUPPORT ON TESTING SST FRONT-END AND BACK-END

ESAC supervisor(s): Beatriz Jilete and Tim Flohrer

The Space Surveillance and Tracking segment, under Space Situational Awareness programme, performs research and development activities for high –level services to users in the field of object cataloguing, conjunction risk analysis, re-entry prediction analysis, fragmentation analysis, special mission support, sub-catalogue characterisation and mission characterisation.

The SST segment can be divided in a front-end and a backend as follows:

Back-end: the core of the system comprised of Data Processing Chain, Sensor Simulator and Planning System
Front-end: the services provided to external users. Concretely Conjunction Prediction System, Re-entry Prediction System, Fragmentation Analysis System and Catalogue Query System, reachable via the SST Web portal

The trainee was asked to help with the operation of the SST Web portal for test and validation purposes by means of procedures and scripts, optimising the automatic and manual executions of CPS, RPS, CQS and FAS systems. These four systems were being executed in a daily base fed-up with orbital information gathered in the database. The trainee was also asked to simulate orbital information or use real orbital data provided by real sensors to analyse the capabilities of the Data Processing Chain system in terms of correlation and orbit determination quality.

13. EXPLORING THE SCIENTIFIC DATABASE OF THE PLANETARY SCIENCE ARCHIVE

ESAC supervisor(s): Sebastien Besse, Claire Vallat, Santa Martinez, Emmanuel Grotheer and the PSA team.

The Planetary Science Archive (PSA) of the European Space Agency (ESA) is a repository for all scientific and engineering products returned by ESA's Solar System missions. It ensures access to scientific products for decades to the public and the science community.

The PSA consists of a database of 12 million scientific products divided by instruments (cameras, particle detectors, etc.), targets (planets, comets, etc.), and scientific disciplines (geology, plasma, etc..). Many very important scientific discoveries and publications are published every year based on observations downloaded from the PSA, and this could be improved even further. In fact, scientific observations from archives are more likely to be used if the descriptions and the metadata clearly point the scientific users to the data they need.

The project provided an assessment and a report on the metadata descriptions of scientific datasets from the PSA database, with all of this based on scientific interests and criteria. The selected trainee was asked to evaluate in particular if metadata describing the content of the products (e.g., target, instrument mode, etc.) are compatible with the current and foreseen new PSA services, and suitable for scientific research.

The output of the project served as inputs to provide a better description of the scientific content of the Planetary Science Archive to the end-users. Further, the results of the assessment served as inputs to improve the mapping between the PSA services and the metadata of the products.

The project help the traine with becoming familiar with planetary science in general given the wide diversity of products available at the PSA and to explore the contents of the database.

14. VISUALIZATION OF ESAC SCIENCE ARCHIVES ACCESSES WORLDWIDE IN NEAR REAL-TIME

ESAC supervisor(s): Beatriz Martinez and Bruno Merin

The data generated by ESA astronomy, planetary and heliophysics scientific missions are stored at the archives developed and managed by the ESAC Science Data Centre (ESDC) (http://archives.esac.esa.int). These archives are constantly accessed by scientists all around the world. The access events are tracked internally at every individual archive, among other statistics.

The aim of the project was to produce a captivating way to illustrate this, by creating a map of recent accesses, which displays the approximate location of scientists. In order to prepare this map trainee had to extract and compile in near real time the necessary user accesses information from all the archive's statistics and develop a web application that allows the visualization within a world map, in near real-time, of the geolocation of the access events.

The output of the project was exhibited to the public through various forms (e.g. on the ESDC web site, in the archives data centre at ESAC, in international conferences and workshops, in archives related events).

15. VISUALIZING THE SUN-EARTH CONNECTION

ESAC supervisor(s): Arnaud Masson, Beatriz Martinez, Pedro Osuna and Ioannis Zouganelis

The SOlar Heliospheric Observatory (SOHO) Science Archive (SSA) of the European Space Agency provides access to data acquired by the SOHO satellite since 1996, i.e. over the past two solar cycles. Meanwhile, the Cluster mission composed of 4 satellites has been orbiting the Earth's magnetosphere since 2000. Cluster data is available at the Cluster Science Archive (CSA).

Visualizing a combination of data collected by these two missions would be of great help for scientists to better understand how the Sun impacts the Earth's space environment.

The goal of project was to develop a proof of concept for a new web interface to the SOHO and the Cluster archives that would allow to search by solar events (cross-matching with the Heliophysics Events Knowledgebase, HEK and the Coronal Mass Ejections CACTUS database). It would display the events found on top of SOHO EIT and LASCO images. Then, data collected at the Lagrangian L1 point by the SOHO CELIAS proton monitor (e.g. Velocity, Density) with a time delay would be displayed. Data at the Earth bow shock (so- called OMNI data) would then be displayed. At the bottom, a set of pregenerated plots of Cluster measurements (time delayed with respect to SOHO remote- sensing) would enable to visualize its impact on the Earth's magnetosphere. It included the location of the Cluster mission on the side and would enable a quick access to download the related SOHO and Cluster data. All time periods fitting the criteria set by the user would be downloadable.

16. VISUALISING NETWORK INFORMATION THROUGH A WEB INTERFACE TOOL

ESAC supervisor(s): Fortunato Navarro, Silvia de Castro, Cristiano Silvagni

The esait at ESAC was deploying a web tool to manage and track the lifecycle of the IT network and datacentre devices as a Proof of Concept that would eventually be expanded to other ESA major sites. The current application is based on an open source project which needed further customization to suit the needs of the Agency in terms of security, reporting, access control, interface with other tools and usability.

The aim of this project was to develop extensions and add-ins to the application and develop independent external functionalities that are able to retrieve information from the main database to provide periodic reports of data content, application usage monitoring and data quality checks.

17. RECONSTRUCTING SPACECRAFT EPHEMERIS WITH SPICE FOR ESA PLANETARY MISSIONS

ESAC supervisor(s): Marc Costa, Christophe Arviset, Sebastien Besse and Björn Grieger

SPICE is an information system the purpose of which is to provide scientists the observation geometry needed to plan scientific observations and to analyze the data returned from those observations. SPICE is comprised of a suite of data files, often called kernels, and software -mostly subroutines-. SPICE is the ‘de facto’ standard for geometry computations among the Planetary Science community, and is used in ESA Solar System Exploration missions in both the planning of the science observations and the exploitation of science data.

SPICE data is available for all missions in operations (Mars Express and ExoMars 2016), missions in development (JUICE, BepiColombo and Solar Orbiter) and for missions in post operations (Venus Express and Rosetta). Unfortunately legacy missions such as Huygens (the probe on-board of Cassini), Giotto, SMART-1 or Chandrayaan-1 do not always have consolidated SPICE datasets -in fact, some of them do not even exist-. Because of this sometimes it is hard to derive precise geometry for the analysis of science data of those missions and given the increasing interest to use some of these data -such as the growing interest that the cometary data provided by Giotto has due to the high success of Rosetta- it is paramount to be able to provide to the science community a consolidate SPICE dataset for these missions.

A SPICE dataset includes, amongst other information, trajectory and orientation information of the given spacecraft along with a model of its payload. For this project the trainee was asked to model the reference frames and payload of the selected legacy missions and to prototype the generation of ‘high precision’ SP-Kernels and C-Kernels (for trajectory and orientation information) in addition during this process the trainee contributed to the expansion and enhancement of libraries devoted to the exploitation of SPICE data. After getting familiar with SPICE, Flight Dynamics data, spacecraft housekeeping telemetry and with PDS Science data, the trainee assessed and characterised the available information required to generate SPICE kernels and evaluated its quality and had oppotunity to start-up the ambitious task of contributing to the generation of SPICE datasets for ESA Legacy Missions.

18. DESIGN OF A MILLIMETRE-WAVE POLARIZATION CALIBRATION NANO-SATELLITE

ESAC supervisor(s): Marcos Lopez-Caniego, Xavier Dupac, Jorge Fauste

Experiments searching for primordial gravitational waves studying the polarization of the cosmic microwave background radiation require robust absolute measurements of the polarization orientation, ideally below one tenth of a degree, to discriminate instrument systematics and induced signals, something that it is currently not possible. The project was designed to design of a bright, compact and linearly polarized source to be flown on a nano-satellite, building upon existing proposals in the literature. The polarization orientation of this calibration source was ment to be known to the level of precision required for ground-based and sub-orbital millimetre wave polarimeters used in experiments like QUIJOTE, SPTPol, ACTPOL, Simons Array, etc., currently operating from the Canary Islands, Antarctica and Chile, as well as for future CMB polarization experiments under study like CMB-S4, funded in the US by DOE/NSF, and similar initiatives from the European CMB community.

In order to acomplish the task the trainee had to select the number and frequency of the tones required to build a good calibrator, taking into account the atmospheric transmittance spectra, the limitations from international regulations and the needs from current and future CMB polarimeters, particularly those located in Europe, and define the requirements with respect to size, power and operational environment (orbit, ground station, etc).

19. COMMON TEST REPORTS: TESTING REPORTS IN CONFLUENCE

ESAC supervisor(s): Fernando Perez and Vicente Navarro

Software Testing is a key process during the development of a Science Operations Centre. There are several testing frameworks, which are widely used at ESAC depending of the development phase. The selection of the tool/framework depends on the SOC: JUnit, JMeter, Cucumber, Robot Framework, Selenium.

The results of the testing provided by these tools are different in terms of information and formats. Currently, most of the ESAC projects use Confluence and JIRA for documentation and reporting and issue tracking. In particular, ESAC provides a common infrastructure for science operations configuration control, SOCCI that provides support to existing and new ESAC projects and make extensive use of JIRA and Confluence.

Testing results should provide the same kind of information and should be integrated in Confluence and JIRA tools with the rest of project information. This guarantees a common approach for testing between projects facilitates the transference of knowledge between people and projects and ensures the preservation of the testing data.

This project focused on the development of a generic tool and API, to transfer the information from the mentioned testing frameworks to JIRA and Confluence in a consistent, agnostic and uniform way basing Confluence testing reports on templates, which can be filled with the information generated by the testing frameworks independently of the framework used.

Additionally, in case of errors, the tool/API is able to generate issues in JIRA for further investigation and resolution, is compatible with SOCCI and integrated as part of SOCCI infrastructure; but at the same time can be used in development missions (e.g. BepiColombo).

20. CUBESAT: ATTITUDE DETERMINATION AND CONTROL SYSTEM AND DEMONSTRATOR

ESAC supervisor(s): Julio Gallegos, Xavier Dupac and Fernando Martin-Porqueras

A CubeSat is a nano-satellite originally developed at Stanford and CalPoly (San Luis Obispo) Universities and was proposed as a vehicle to support hands-on university-level space education and opportunities for low-cost space access.

A ground station (GS) for cubesats (UHF/VHF) is operational since mid-2017 at ESAC. This project is the continuation, now on the cubesat part. The prime objective of this project was to complete the attitude determination and control system for the cubesat (ADCS) based on reaction wheels and, in parallel, work on the demonstrator: an air bearing system providing enough lift to allow 6DoF for the cubesat. A prototype was already built, and the trainee had to work to produce the final product.

To complete the project our trainee had to test the link between GS and cubesat demonstrator, build the ADCS (based on reaction wheels), command the cubesat attitude from the GS.

21. GNSS SCIENCE FOR EVERYONE: SCIENTIFIC APPLICATIONS USING RAW GNSS MEASUREMENTS FROM ANDROID SMARTPHONES

ESAC supervisor(s): Vicente Navarro, Manuel Castillo, Roberto Prieto, Fernando Martin-Porqueras

The GNSS Science Office shall support the development and operation of complementary GNSS Data Systems Infrastructure to maximise GNSS Science Opportunities in Europe.

Current on-going actions for this complementary infrastructure include (non-exhaustive list):

Reinforcement of ESA role on the IGS community becoming a worldwide reference as IGS Global Data Center.
Establishment of a GNSS Science Service Center providing access to archived information on ESA GNSS scientific activities and GNSS service areas.

As a core activity, the GNSS Science Office evaluates candidate technologies and algorithms in order to enable innovative GNSS Science Services.

Hence, within the scope of the aforementioned on-going actions an ESAC trainee project is proposed to carry out an assessment of the scientific application of Android smartphones raw GNSS measurements. There are still some obstacles preventing smartphones from competing with low-cost RTK units, namely the quality of the antenna and the duty cycling of the GNSS receiver. Nevertheless the new feature included in the last version of Android to provide GNSS receiver raw data may enable the implementation of semi-precise positioning. A priori, this feature may bring a number of scientific applications with GNSS (atmospheric physics, metrology, ...) closer to the typical handheld user.

Investigation in this area would explore advantages and disadvantages associated to the utilisation of these devices as GNSS science instruments. Moreover. as part of the scope of the future GNSS Science Service Center, results and data from this project are to be coordinated with active projects on GNSS and Big Data.

The trainee selected for this project is expected to acquire knowledge related to archiving and exploitation of GNSS information for scientific purposes (see http://gssc.esa.int - currently under construction).

22. OB STARS IN THE SOLAR NEIGHBOURHOOD AS OBSERVED BY GAIA

ESAC supervisor(s): Jesús Maíz Apellániz and Danny Lennon

The second Gaia data release is expected to take place on the northern spring of 2018, producing for the first time high-precision parallaxes and proper motions for ~1,000,000,000 Galactic stars. At the same time, our research group has access to the Galactic O-Star Spectroscopic Survey (GOSSS) and four high-resolution multi-epoch optical spectroscopic surveys (OWN, IACOB, CAFÉ-BEANS, and NoMaDS). GOSSS provides the selection of a magnitude-complete sample of ~400 O stars in the solar neighbourhood and the high-resolution surveys provide precise radial velocities (with multi-epoch measurements of spectroscopic binaries) and stellar parameters. Therefore, for the first time we can have an accurate and complete knowledge of the spatial distribution of the O-type stellar population in the solar neighbourhood. In this project we will use these data as well as complementary data for B stars and A supergiants to study the Galactic rotation curve, the location and dynamical effect of nearby spiral arms, the distances to known clusters and associations, the height scale for massive stars, and the spatial distribution of dust.

23. DISCOVERY AND CHARACTERIZATION OF HOT SUBDWARFS USING THE VIRTUAL OBSERVATORY

ESAC supervisor(s): Enrique Solano and Rosario Lorente

Hot subdwarf stars (hot sds) are objects with temperatures exceeding 19,000 K and surface gravities larger than log g=4.0. They are considered to be the field counterparts of the extended horizontal-branch (EHB) stars found in globular clusters.

In this project we proposed to work on the identification and characterization of new hot subdwarf candidates following the criteria described in Oreiro et al. (2011, A&A 530A, 2) and making use of the UKIDSS/VISTA and Gaia catalogues and Virtual Observatory tools. UKIDSS/VISTA allows to identify faint objects beyond the 2MASS limiting magnitude while the use of Gaia (DR2) proper motions and parallaxes significantly improves the separation between hot subdwarfs and other "contaminants" like OB Main Sequence stars or white dwarfs.

24. VO SCIENTIFIC EXPLOITATION OF WIDE-AREA SURVEYS

ESAC supervisor(s): Miriam Cortes, Enrique Solano, Rosario Lorente

Virtual Observatory constitutes an excellent methodology to analyse the wealth of information available in images with a large field of view. The project was focused on the set of images (several thousands, 2 Tb) taken at La Sagra Observatory from November 2015 until now, in the context of the project H2020 Small Body Near and Far (SBNAF, http://cordis.europa.eu/project/rcn/199146\_en.html).

The main tasks to be accomplished in the project were the following:

Astrometrical calibration using Gaia data.
Identification of asteroids. Submission of the astrometrical information to the Minor Planet Center
Analysis of the temporal information of the asteroids analysed in the previous step. Identification of new asteroids, NEOs or fast object on the filed of view.
Identification and characterization of known and new variable stars using the Gaia catalogue.

25. PREPARATION OF SCIENCE CASES FOR THE CESAR EDUCATION INITIATIVE

ESAC supervisor(s): Michel Breitfellner, Beatriz Gonzalez, Manuel Castillo and Javier Ventura

CESAR (Cooperation through Education in Science and Astronomy Research) is a joint educational programme developed by the European Space Agency (ESA), the Spanish National Institute for Aerospace Technology (INTA) and INTA-owned company Isdefe. Its objective is to provide students from European secondary schools and universities with hands-on experience in Optical and Radio Astronomy. In addition, CESAR shall contribute with outreach activities to promote Space Science and to stimulate European students' interest in Science and Technology in general and Astronomy in particular.

To help school teachers and university professors to use the CESAR telescope and IT infrastructure efficiently, proper documentation had to be written characterizing existing hard and software and how it is used. Furthermore, science and education cases had to be proposed dealing with different topics (e.g. define the solar activity cycle by counting sunspots, how to measure distances in the universe, etc.) at different levels of difficulty, so that they can be used as starting points in schools and/or university classes. These cases had to be presented in a simple and attractive way without sacrificing the mathematical and physical formalism necessary.

The project objective was the development and proper documentation of at least two science and education (sci&edu) cases in collaboration with scientists and teachers:

Define the sci&edu case in its historical context and actual importance.
Explain which astronomical observations are necessary and why.
Describe the instrumentation necessary to obtain useful data.
Prepare a guide explaining how to plan and carry out the astronomical observations using the CESAR telescopes.
Explain how scientists extract the essential information from obtained raw data.
Demonstrate how a proper error estimate is done.
If possible, break the case down into different levels of difficulty so that it can be used by pupils with different skill levels.
Participate in the testing of the instrumentation foreseen to carry out this sci&edu case.

26. CESAR SOLAR OBSERVATORY MASTER CONTROL PROGRAM

ESAC supervisor(s): Miguel Perez-Ayúcar, Santa Martinez, Michel Breitfellner, Abel Burgos, Javier Ventura

CESAR (Cooperation through Education in Science and Astronomy Research) is a joint educational programme developed by the European Space Agency (ESA), the Spanish National Institute for Aerospace Technology (INTA) and INTA-owned company ISDEFE. Its objective is to provide students from European secondary schools and universities with hands-on experience in Optical and Radio Astronomy. In addition, CESAR shall contribute with outreach activities to promote Space Science and to stimulate European students' interest in Science and Technology in general and Astronomy in particular.

As part of the CESAR initiative, a permanent Solar Observatory (CESO) was installed at ESAC, Madrid, Spain in 2012 http://www.cosmos.esa.int/web/cesar/esac-solar-observatory. It consists of two telescopes:

Coronado Solarmax II 90 with a double Stack Filter, in H-alpha and a
Bresser AR-102, in visible (white-light).

The telescopes are mounted on a Celestron CGEM GOTO mount, installed in a Scopedome 3M. The dome is connected to a AAG CloudWatcher weather station. The cameras currently used are two QHY5-II. A second set of portable telescopes, mounts and cameras is also available for testing, and specific observations from remote locations.

The CESAR ESAC Solar Observatory (CESO) is designed to work completely autonomous delivering H-alpha and visible light images every minute if meteorological conditions allow it. Those images are acquired by two QHY5-II cameras and transferred from the computers in the dome to a server where they are processed and archived. Last processed images are displayed on the CESAR webpage: http://cesar-programme.cab.inta-csic.es/sun.php?Section=Play

The project objective was to create a master program that controls the automatic and remote operations of the Solar Observatory at ESAC. It entails the following aspects:

Understand how the current Helios observatory works, and which parts are key for a master control program.
- the Observatory is composed of the dome, weather station, mount, telescopes, cameras, focusers, guiding system, master computers, network connections for data transfer, webcams, power UPS
- the basic steps of the observatory operations are:
  - switch on units at daybreak
  - check on weather conditions and open dome
  - point telescopes to Sun and track
  - initiate image capture and processing pipelines
  - flip mount at meridian pass
  - stop imaging, pipelines and close dome before sunset
  - monitor weather conditions and actuate of dome closure-opening
Create the underlying master control program to control the daily operations of the Observatory, using Python and ASCOM as the programming languages and platforms.
Create an intuitive simple GUI for an operator to control the operations of the Observatory.
- Two levels of automation are foreseen: semi-automatic with manual intervention, and fully automatic.
- OK-NOT_OK displays should be available for the operator to understand the units status.
- Parameter windows should be available for the operator to monitor the current observation status. This should be linked to the sub-systems status.

The final result of the project should be a working image processing pipeline running on the new CESAR infrastructure including a detailed document explaining its design and usage.

27. SOFTWARE DEVELOPMENT FOR SPACE SCIENCE EDUCATION IN CESAR

ESAC supervisor(s): David Cabezas, Michel Breitfellner and Javier Ventura

The CESAR initiative has its own observing facilities which allow to observe the universe actively on-line through a dedicated Control Centre hosted at the European Space Astronomy Centre (ESAC) in Madrid, Spain.

The objective of this project was to develop and document new IT components including hardware and software for CESAR. The main tasks included:

Software integration and interconnection of subsystems.
New software creation for education using the latest technologies (for mobile, vr glasses, 3D interfaces, robotics).
Ensure compatibility of different IT component.
Integrate the CESAR observatories into the CESAR network.
Linux server configuration for the computer sub-network in lecture room A.041b.
Support on-line events like Google hangouts and videoconferences.

The project resulted in new software for the CESAR IT infrastructure.

SCI-S Trainees