The Leiden/ESA Astrophysics Program for Summer Students (LEAPS)
Leiden Observatory and ESA are pleased to welcome applications for the second edition of the LEAPS program. LEAPS is an opportunity for students with an interest in astronomy and astrophysics to perform a 10-12 week summer research project in collaboration with a research scientist from Leiden Observatory or ESA. The program is open to all students not currently engaged in a Ph.D. program, although we are most interested in students at the senior-undergraduate or masters level who are enthusiastic about research in astrophysics.
Students will be selected for the program based on their academic achievements and research potential, and will be matched to staff projects based on what they indicate their scientific interests to be. Research at Leiden Observatory and ESA takes place on a diverse array of topics (see below), and student projects will likely consist of anything from the analysis of data from world-class telescopes, to large computer simulations, to hands-on work in the astrochemistry laboratories.
Projects will begin in June 2014 and end before mid-September 2014. We expect to make as many as 20 appointments this year, depending on interest and the match of projects to students interests and skills. Details on the application process can be found below.
Leiden Observatory is a world-class institute for research in astronomy and astrophysics based in the Netherlands, approximately 35km from Amsterdam. The atmosphere at the observatory is dynamic, with approximately 100 faculty/research scientists and 70 graduate students engaged in astrophysical research on a wide range of topics. Major fields of interest include extrasolar planets, star formation, cosmology, galaxy formation, instrumentation, and astrochemistry. Multiple research projects will likely be available within these fields.
European Space Research and Technology Centre (ESTEC/ESA)
ESTEC is the main technical centre for the European Space Agency (ESA), responsible for spacecraft integration. ESA develops and manages many types of space missions, from exploration, telecommunications, to earth and space science. The Research and Scientific Support Department at ESTEC consists of approximately 40 staff scientists, with research interests ranging from the geology of planets in our solar system, to plasma physics in the magnetosphere of the Earth, space weather, to observational astronomy with ESA's space missions such as Planck, Herschel, GAIA and EUCLID. Due to tight security requirements for entry to the ESTEC complex, students who work in collaboration with the ESTEC Research Fellows will be based primarily at Leiden Observatory and their advisor will meet with them on a regular basis.
Travel, Housing and Stipend
Students accepted into the LEAPS program will be provided with travel costs to/from Leiden. We will also provide housing accommodations near the observatory, as well as a modest stipend to help with living costs during the internship. Leiden is a small, picturesque university town located between the major cities of Amsterdam and The Hague. Summer is a beautiful time of year to be in Leiden, and we encourage LEAPS students to socialize and use their free time to enjoy the numerous summertime activities available in Holland. English is widely spoken throughout the Netherlands and international students should find it easy to live in the Leiden area. We are planning several field trips for LEAPS students including visits to the ESTEC complex where many ESA satellites are being built, and potentially to the LOFAR radio array, the world's largest low-frequency radio telescope.
How to Apply
The program is open to all international students provided they are not currently enrolled in a Ph.D. program. ESA projects are only available for students from ESA member or affiliate states (Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, The Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland, the United Kingdom and Canada). Students from Cyprus, Estonia, Hungary, Latvia and Slovenia (affilliate members) can also apply for ESA projects. The working language of the observatory is English, and students should be sufficiently proficient in English to perform a research project.
To apply, please go to the web submission form and first answer the questions on the form. This includes selecting three projects from the Areas of Research list below that you are most interested in working on. Please note that the submission page requires the creation of a username and password. On the submission page you are also required to submit the following (in PDF format please):
a one-page document describing your interest in an area of astrophysics research relevant to staff members (see below), as well as details of any previous research experience or relevant research skills (e.g., scientific computer programming).
the name and contact details of an academic who has been asked to submit a letter of reference for you. This person should be able to speak to your potential to carry out scientific research, rather than just your performance in undergraduate lectures. Letters of recommendation must be received by the application deadline, please make sure your referee is aware of this.
a transcript of undergraduate/masters level course grades.
a curriculum vitae (optional, but helpful).
Once you have submitted you application, or saved a draft version, an email will be sent to your reference letter writer requesting the letter. Students will be evaluated for participation in the program on the basis of their research potential and match to available projects in their area(s) of interest. All fully-complete applications received by February 15, 2014, 23:59 CET will receive full consideration. We expect to inform all applicants on the outcome of their submission by the end of March.
Deadline for applications: February 15, 2014, 23:59 CET
If you have any questions about the application process or the program, please . If you want to know more about the projects on offer, please email the project supervisor directly by clicking on their name below.
The Oort Cloud is an inferred structure at the edge of the solar system, believed to be the source of
nearly-isotropic comets (NICs). These objects are possibly the most primitive of the solar system.
However, they are mostly unexplored, because observing such comets in the inner solar system is
quite a rare event. The newly-discovered NIC C/2013 A1 (Siding Spring) is thus an exceptional
object. In addition, it will perform a close encounter with Mars in October 2014, flying by the
planet surface at ~100,000km. This will be a unique opportunity to study it in great detail from
Mars-based assets like the ESA/Mars Express spacecraft (MEX). Before the comet can be observed
from MEX, it will be studied from ground-based telescopes. The comet is currently being
monitored as it becomes more and more active, unveiling its primordial volatile content.
The purpose of the proposed internship is to study the visible and near-infrared spectra, which are
being obtained from the ESO/VLT with XShooter. After data reduction, the spectra will be analyzed
and modeled in order to characterize the nature of this comet surface, and the composition of the
material ejected from this surface.
Variability and transiting extrasolar planets in young open clusters
So far only little is known about exoplanets during the first few millions of years of their lives, and the goal is to fill the observational gap. Any detection of an exoplanet in these young clusters would provide important constraints on planet formation and migration time-scales and their relation to protoplanetary disc lifetimes. Young open clusters provide an ideal environment for the search for young extrasolar planets, since they feature a relatively large number of stars of the same known age and metallicity at the same distance. In cooperation with the Young Exoplanet Transit Initiative (YETI, Neuhäuser et al. 2011) several 0.2 to 2.6 m telescopes around the world will be used to monitor continuously young (< 10 Myr), nearby (< 1 kpc) stellar clusters mainly to detect young transiting planets and to study variability phenomena on time-scales from minutes to years. The telescope network enables us to observe the targets continuously for several days in order not to miss any transit. The project aims to analyze photometric data taken of a selected open cluster observed with telescopes of the YETI network. The light curves which will be obtained during the project will be used to search for transiting exoplanets and study any kind of variability.
Space weather conditions in the inner heliosphere
Type of project: Planetary Science; Observational; ESA
Seeing the Sun anytime... now it is possible, even in the Netherlands! Today there is a vast amount of spacecraft observing our central star and the terrestrial space environment. The 11-year period solar activity cycle is now at its maximum producing spectacular solar eruptions that are injected all over into the interplanetary space. These can disturb spacecraft operations and interact with planetary magnetospheres or atmospheres resulting in beautiful aurora. Scientists admire this display of nature and they survey our near space environment in order to protect our highly developed technology in space.
This Summer, you can be part of this community! Help us survey the Sun by using nearly real-time solar and heliospheric images and movies observed directly from space, forecast when the solar eruption would arrive at Earth or other planets. We will then interpret the plasma measurements at the different terrestrial planets: Venus, Earth and Mars.
If you are interested in space, you like geometry and computers do not scare you, then your place is here...
Modeling of the Hermean Exosphere
Type of project: computational; planetary (solar system); ESA
The Hermean Exosphere Model of Oxygen (HEMO) was originally created to explore the open question of why oxygen seems to be underrepresented in Mercury's exosphere, especially when compared to sodium. These simulations have since been expanded to cover other atmospheric constituents. Processes included in the simulation are meteoritic impact vaporization, gravity, photoionization, and photodissociation. The candidate will help develop new methods of displaying the results of these simulations in graphical form. Knowledge of MATLAB is preferable, though other programming languages could potentially be used as well. Depending on the abilities of the candidate, the project can be expanded to include development of new modules to be utilized in future simulation runs.
The fleet of new missions and instruments sent to the Moon since 2007 offer new capabilities in the examination of the lunar surface. Large volcanic lava flows, also known as "Mare Basalts" consist of individual flows that can be identified in several different ways. Improvements of the latest instruments have shown that the previous mapping of lava flows boundaries has to be updated. New mineralogical boundaries have been identified using the Moon Mineralogy Mapper observations and seem to agree with morphological boundaries identified during the Apollo era for the Imbrium basin. This new project will make use of the latest visible images to map individual flows based on morphological criteria only within the Imbrium basin. It will allow comparison with mineralogical boundaries and assess if mineralogical units are made of single or multiple individual flows. This project will used the latest observations of the lunar surface from Lunar Reconnaissance Orbiter, SMART-1 and Kaguya observations.
The occurrence of lightning in the Venus atmosphere remains controversial, largely because the evidence for optical flashes is ambiguous. It has long been proposed that Venus lightning could be detected –if it occurs, and its intensity is comparable to Earth flashes- from ground-based telescopes by taking short-exposure, high-cadence images of the planet. This exciting project intends to assess the occurrence of lightning on Venus with existent photometric observations made at a number of 1-2 m telescopes over the world. The trainee will interact with the mentor and colleagues at ESTEC to identify the optimal strategy to hunt for this type of sporadic events in images of Venus. The project is relevant to a number of ESA missions exploring the atmospheres of the Solar System planets. The trainee will learn/use techniques that are applicable to the search of sporadic events in other fields of astrophysics.
The Chamaeleon-Musca Dark Cloud Complex is one of the nearest low-mass star forming regions occupying an area of several square degrees on the southern sky. Interestingly, the four clouds belonging to the complex show very different star formation history. While Cha I has probably reached the end of star formation, Cha II is still actively forming stars, while Cha III and Musca seem to be quiescent. In this project, we will analyze deep optical and near-infrared observations of the Musca cloud obtained with the Blanco 4 m telescope at Cerro Tololo. We will complement this data set with archival Spitzer and WISE images, and look for young stellar objects (YSOs) in Musca. A negative result would place a stringent upper limit for the star formation process, while finding YSOs would change the current paradigm on the Musca cloud in terms of star formation activity. The physical reason for the different star formation activity in Musca and Chamaeleon is unknown. One possibility is that it is related to the different internal structure of the clouds and filaments. To test this with our deep observations, we will use the reddening of background stars caused by the cloud, and analyze cloud structure to reveal similarities or differences compared to Chamaeleon and other low-mass star forming regions.
Fragmentation of star forming cores: a relation with the total energy or not?
Type of project: Astronomy, star formation, observational (using ALMA archive)
Stars more massive than 3 solar masses form predominantly in clusters. Clustered star formation is an interesting topic where many things are unknown. Low-mass stars predominantly form in isolation while high-mass stars form in large rich star clusters. In between these two extreme cases the intermediate mass stars form in small protoclusters. ALMA allows us to view individual envelopes and disks of the cold dust around each member. For these clusters, it is not known if a more massive source is forming near the gravitational center or not. This measurable aspect can be used to test various star formation theories. Using the recently opened ALMA archive, the student will inspect the continuum emission of the cold dust, determine masses and luminositiies of all individual members of a cluster and thereby test various star formation theories.
Using computational tools to study the molecular gas in planetary nebulae
Type of project: Astrochemistry, circumstellar medium; molecular gas; computational
When low- or intermediate-mass stars get old, they expel their external layers to the interstellar medium. The exposed dense and hot core (which is evolving to become a white dwarf star) ionizes the ejected material producing the beautiful objects called planetary nebulae (PNe; http://hubblesite.org/gallery/album/nebula/planetary/). In this project, the student will use a computational code to simulate the physical conditions and study the molecular gas emission around PNe. The results will be used to interpret recent data obtained with the Herschel Space Observatory. Among other quantities, the code calculates the density of different chemical species (atoms and molecules) and the expected emitted spectra. The intensity of emission lines can be compared to observed values, helping us to understand the physical and chemical processes ongoing in PNe. They can also be used to infer the physical properties of PNe (gas total density, temperature and luminosity of the central star, etc.) from observed spectra. In this project, the student will learn about the physics and chemistry in PNe (which can be applied to other photoionized nebulae) and will receive training in the use of the computational code. This project is part of a bigger project and may lead to publication.
Understanding the warm gas in massive star forming regions
Type of project: Astrophysics, star formation; observational
Massive stars are the ones we see in external galaxies because they burn brighter and hotter than stars like the sun. From their light we extrapolate an entire ‘initial mass function’ worth of stellar mass in those galaxies. Massive protostars produce strong stellar winds from an early age, likely disrupting their accretion flows in the process. When a forming massive star begins producing a high ionising photon flux an HII region forms and grows outwards.Our current understanding of how this progresses is firmly rooted in 1940s physics, with little further development over the years. In this project, we will explore the dynamics in small HII regions (using hydrogen and helium recombination lines) and how that correlates with the dynamics of the surrounding warm molecular gas (as traced with sulphur dioxide) from APEX observations of four massive star forming regions. These results can then be compared to high resolution data of similar sources in the ALMA archive.
Impact of astronomy education and public outreach on astronomical research
Type of project: education and public outreach; science communication
Astronomy covers a very broad area of research with a great photogenic appeal and a scale and scope that go far beyond our daily lives to stimulate the imagination. The way that astronomers make sense of the Universe has changed dramatically in the last decades. Astronomy is now a global collaborative science, bring together nations in international organisations and collaborations to answer some of mod rooted questions of mankind. Following the same trend, education and public outreach (EPO) in astronomy has also change and it's now a truly global endeavour. But what is the real impact astronomy EPO on astronomical research? During the project we will explore the rationale for building awareness and support of astronomy among the public and decision-makers, looking at the societal and economical impact.
Finding the brightest transiting exoplanets using the Multi-site All-Sky CAmeRA (MASCARA)
Type of project: exoplanets; observational; data analysis
MASCARA, the Multi-site All-sky CAmeRA, is an instrument concept that will consist of several stations distributed across the globe, with each station containing a few cameras to monitor the near-entire sky at each location. Its purpose is to find exoplanets transiting the brightest stars (in the V=4-8 magnitude range) - currently not probed by space- or ground-based surveys. The nearby transiting planet systems that MASCARA will discover will be key targets for detailed planet atmosphere observations. By the end of March 2014, the first MASCARA station will be deployed in La Palma. Once operational, we will take 5 images of the sky every 6 seconds of every clear night, therefore accumulating a large amount of photometric light curves to analyse almost in real-time. In order to find exoplanets, the light curves need to be optimally calibrated making a precise transmission map of the entire sky and the lens at any given time. In addition to working on light curve calibration, the student will also help developing the pipeline that will automatically fit the light curves to find transiting planets, which could potentially lead to MASCARA's first exoplanet discovery.
The first generation of massive black holes
Type of project: observational or theoretical, black holes
The formation of the first generation of supermassive black holes is an unsolved problem. Only 800 Myr after the beginning of the Universe, we observe extremely massive black holes, roughly 10^9 times the mass of the Sun. Given the short timescale and the physical limits to black hole growth, it is unlikely that these black holes formed from the remnants of normal stars. It is the goal of this project to constraint other physical mechanisms for the formation of such black holes. Depending on the inclination of the student, this project can be observational or theoretical. In the observational project, the student will explore the constraints on the black hole formation mechanism in the early universe using data from optical (Hubble) and x-ray (Chandra, XMM-Newton) satellites. The theoretical project will use dark matter simulations as a backbone to explore the dependence of observational signatures of forming black holes on the underlying physical mechanism.
Let's get AMUSEd!
Type of project: computational; theoretical; simulations
The Astrophysical Multipurpose Software Environment -- AMUSE (www.amusecode.org) -- allows to simulate and model a broad variety of physical processes over a wide range of scales. It uses Python interface with existing numerical codes. These can be combined and coupled to study multi-physics problems including gravitational dynamics, stellar evolution, hydrodynamics, and radiative transfer. The student will be tutored on the use of AMUSE and apply it on an astrophysical question. Possible projects could for example investigate the influence galactic tidal field on star cluster that radially migrated or a study of proto-planetary discs in star clusters.
Complex molecules in a young solar-system analog
Type of project: star formation; astrochemistry; observational
Many of the details of how and under what conditions our own sun formed is still unknown. New high-resolution observations of molecular lines at radio frequencies have the possibilities to peer deep into the forming protostellar structure. In this project the student will analyse high-resolution data from the Plateau de Bure Interferometer of the deeply-embedded low-mass protostar NGC-1333 IRAS 2A in the Perseus star forming region. The data contains detections of several different complex organic molecules, such as methyl formate (CH3OCHO), dimethyl ether (CH3OCH3) and ethyl cyanide (C2H5CN). The observations is sensitive to scales comparable to the size of our own solar system (100~200 AU). Several methods of analysis is applicable, such as uv plane analysis, imaging of interferometric data, line fitting/identification just to mention a few. In the end the student is expected to have gained experienced in working with and doing simple analysis of interferometric data and gained insights in the astrochemistry of protostellar cores, which undoubtedly will be useful for future endeavours of all kinds.
The dust and gas on Galactic scales
Type of project: star formation; molecular clouds; observational
When trying to understand star formation in other galaxies the smallest resolvable unit is at best a small molecular cloud, at worst a significant part of a spiral arm. While the large-scale structure (e.g. spiral arms) is easy to access, assumptions must be made such as how the dust and gas are related or how 'clumpy' star formation is. Studies of star formation within our galaxies have the opposite problem - we can resolve individual protostars but have difficulty understanding the large-scale structure due to observing it from the inside. With new surveys of both gas (Exeter-FCRAO CO Survey) and dust (Herschel Hi-GAL) we are now able to bridge this gap for the first time, studying how they are related to each other and star formation on Galactic scales, thus providing the extragalactic community with specific answers to their unknowns. In this project we will use both surveys to extract the clumping factor in the dust as a function of wavelength and in the gas. We will also produce dust temperature and column density maps which can then be compared to similar maps for the gas to obtain the dust-to-molecular gas ratio as a function of galactic longitude and latitude.
Photoabsorption of nitrogen in the extreme-ultraviolet
We have new laboratory spectra of the N2 photoabsorption bands recorded in the extreme-ultraviolet (XUV, λ < 100 nm). These are the highest-resolution broadband absorption measurements ever made at such short wavelengths. We hope to use these measurements to quantify the production of nitrogen atoms by XUV light in interstellar space, protoplanetary disks, and planetary atmospheres. The next step in the project is converting these raw measurements into information about the underlying molecular structure and quantum mechanics. This is a big dataset and any summer student interested in helping out with this could focus on one of several aspects. Some examples are: fast-rotating states at high-temperature (≈ 900 K), spin-forbidden transitions, absorption across a dissociation limit, or isotope-dependent perturbations.
The project would involve learning about and using:
1. The basics of diatomic molecular physics, including perturbations beyond the ideal case.
2. The strengths and weaknesses of working with real experimental data.
3. Programming skills in the python language.
4. Manipulating and fitting absorption lines in spectra.
5. Comparing the results with a coupled-channel quantum-mechanical model of the excited electronic-states (and improving it?).
Understanding the viscous evolution of the inner parts of transition disks
Type of project: star and planet formation; simulations; theoretical
Planets are formed within gaseous and dusty disks around young stellar objects, but it is still unclear many physical mechanisms that play an important role in this formation process such as dust growth and photoevaporation. A very interesting and well-studied kind of circumstellar disks is transition disks, which inner parts are depleted in dust. These disks might reveal an intermediate step of the ongoing disk dispersal process and they are excellent candidates to investigate gas and dust evolution in disks. One of the most exciting ideas to explains the observed properties of these objects is that a massive planet is interacting with the disk. I propose to investigate the fate of the inner part of transition disks by a simple model of the viscous accretion evolution of the disk once a planet (or multiple planet system) has carved a gap. Students who are interesting on learning about planet formation and are willing to learn about the basics of modelling the gas evolution in protoplanetary disks are very welcome.
Molecular anions in photon-dominated regions
Type of project: astrochemistry; interstellar medium; theoretical
Molecular anions (molecules which are negatively charged) are a recent addition to the families of chemical species observed in space. Multiple molecular anions have been observed in molecular clouds, the birth place of stars, and in the circumstellar envelopes (CSEs) around evolved stars. Since their discovery in 2006, the formation and destruction mechanisms of these exotic species have been investigated in the laboratory and in chemical models . Models reproduce the observed abundances in molecular clouds and CSEs; however, the same chemistry significantly over predicts the abundances in photon-dominated regions (PDRs). PDRs are interesting environments which form the interface between the heavily irradiated interstellar medium and molecular clouds. The lack of agreement between PDR models and observations may be due to insufficient destruction mechanisms under irradiated conditions. One poorly constrained reaction is mutual neutralisation, in which a cation and anion react producing the neutral forms of each species, i.e.,
AB- + CD+ ---> AB + CD.
It is possible this process has multiple reaction pathways which can lead to the destruction of the neutral molecule from which the anion forms via the reaction,
AB + e- ---> AB- + hv.
A new laboratory facility currently under development, DESIREE, will finally help constrain both the reaction rate coefficients and product channels of reactions between anions and cations of astrophysical interest. In this project, the student will explore the destruction of molecular anions via mutual neutralisation using a model which simulates the chemistry in a PDR. The student will add new reaction pathways and rate coefficients to investigate if this process contributes to the destruction of molecular anions under PDR conditions. This project is suitable for those with a keen interest in astrochemistry (molecular astrophysics) and may lead to publication in a leading astrophysics journal.
Understanding an analogue of the Solar System birth environment
Type of project: star formation; observational; modelling
Our Solar System likely formed in a cluster of stars. To better understand the formation conditions of the Sun and its planets, we must study star formation regions where multiple stars are presently forming. In this project, the student can choose to investigate one of several aspects of such a clustered star forming region, OMC-2 in the Orion molecular cloud: diving into space telescope imagery to settle the debate about the source luminosity (some authors say 50, some say 1000 Solar luminosities); working with molecular spectra from the Herschel Space Observatory to better understand the chemistry and energetics of this region; or characterizing the larger-scale environment of the cluster, to determine important properties such as the external heating rate and direction. Depending on the chosen direction, the student can learn a range of skills including star and planet formation, photometry, molecular spectroscopy, working with space telescope data and programming in Python.
Are all dwarfs crusty? Dust in occulting dwarf galaxies
Type of project: Astronomy; galaxies; observational
When two galaxies overlap on the sky, they need not be in close proximity. Accidental overlap illuminates the foreground galaxy’s dark, dusty structures. Through differential photometry and spectroscopy, we can learn a lot about the distribution and composition of dust in the foreground galaxy. For this project, new imaging and spectroscopy data has been obtained with the 4m. William Herschel Telescope for some 60 galaxy pairs. The data will have to be reduced and then analyzed: are both galaxies at similar redshifts (interacting pair) or are they well-separated (occulting pair)? How much extinction is evident in the overlap region? What is the extinction curve? Of special interest are pairs where the foreground galaxy is a small dwarf galaxy. Thus far is was always assumed these were mostly dust-free but a recent result on a single occulting pair observed with HST begs to differ; there appears to be dust in the small dwarf galaxy extending well out of the stellar disk (http://heritage.stsci.edu/2008/33/). Is this common? Do all dwarf galaxies have such an extended dust disk? From the bona-fide occulting dwarf galaxies, we will be able to find out.
The Westerbork Synthesis Radio Telescope (WSRT) will be decommissioned within ten years from now and it is not clear what will happen afterwards. It would be a great benefit for the WSRT to be put to a new commercially and/or scientifically attractive use. The WSRT has already been used to assist deep space missions, but there are many more possibilities. The student will conduct research to answer some fundamental questions: what are the potential capabilities of the WSRT when it stops doing science, and what are the current plans (if any) to maintain the facility? In addition, how can we use capabilities in the Telecom sector, and what would it take to get their attention? How can the WSRT help orbiting Earth Observation instruments, e.g. the Sentinel-type missions? Are there other areas where the WSRT can contribute? This research will be an exploration mission. No idea is too wild if the costs and benefits can be properly justified. The future of the WSRT is at stake!
Euclid Attitude Control; how can we please science?
The objective of the Euclid mission (to be Launched in 2020) is to better understand the geometry of dark energy and dark matter by accurately measuring the acceleration of the universe. To achieve this, Euclid will measure the redshift of galaxies at varying distances from Earth and investigate the relationship between distance and redshift. The success of the Euclid mission critically depends on the knowledge of the Point Spread Function (PSF). The Attitude Control System (ACS) of the Euclid Service Module can distort the PSF. External disturbances as well as effects of non-ideal sensors and actuators will result in the attitude “wobbling” around its target attitude. This wobble should either be small enough to be negligible with respect to the instrument PSF and/or have components which can be corrected for in post-processing on ground. The objective of this research program is to determine how good the ACS has to be to meet this objective, what type of a-posteriori corrections would be possible, and what data would then be required from the ACS. The goal of the program is not to go into an in-depth detailed analysis. We would like to answer at a high abstraction level how the ACS can please Science by being as inconspicuous as possible.
Slant column aerosol retrieval
Type of project: atmospheric; Earth observation technique; sun/Mie back scattering; Dutch Space
Aerosols form a major unknown in the Earth atmosphere, both as part of the air quality and as part of the energy balance. In the Netherlands the SPEX instrument for multi-viewing spectral polarimetry is developed for space application and provides aerosol information on typically 5 – 10 km spatial resolution. At Dutch Space the same measurement technique is planned for aircraft-based measurements at, typically, 50 - 100 m resolution, with the ultimate goal of having an operational air quality service. The objective of this study is to set up, from first principles, retrieval for slant column aerosols parameters (particle density, size, index of refraction) to investigate its potential and limitations at the required spatial resolution and in particular mixing with albedo effects. The student will apply Mie scattering theory and general models in combination with primarily simulated measurements.
Turbulence Parameterization for Adaptive Optics
Type of project: theoretical, instrumentation, TNO
Ground-based astronomy with optical telescopes is hampered by wavefront aberrations that are induced by atmospheric turbulence. In order to improve the image resolution , Adaptive Optics (AO) systems are used to counteract the disturbing effects of the atmosphere. A basic AO system consists of a deformable mirror to introduce the wavefront correction, a wavefront sensor to measure the wavefront aberrations, and a control system to compute the desired wavefront correction.
The properties of the AO controller depend on the spatial and temporal characteristics of the atmospheric turbulence. Important parameters are the Fried coherence length, the coherence time, the turbulence outer scale, and the isoplanatic angle. In general, these parameters are not constant but time-variant, which complicates the design of the AO controller.
So far, little effort has been spent worldwide on the characterisation of the essential turbulence parameters; in particular, in the temporal sense. In this assignment, the objective is to estimate linear, stochastic models of the turbulence parameters; for instance, in the form of ARMA-models. The modelling will be done based on datasets generated by various turbulence monitors, such as the GSM (Generalized Seeing Monitor).
study of measurement techniques to estimate the essential turbulence parameters
collection of data-sets from 1 or more monitors
analysis and stochastic model estimation of the turbulence parameters
Simulating Space on Earth; laboratory astrophysics.
Type of project: Laboratory astrophysics; astrochemistry;
In the laboratory we are able to simulate 3 cm of interstellar
cloud using supersonic plasma. A highly sophisticated
infrared laser detection scheme is available to search for
molecular transients that are likely to be present in space.
Within this project you will learn to record spectra and to
analyze the data using PGopher, a highly user friendly software
package optimized to fit complex spectra. The resulting data
are used as input to search for new species in space. The
preparation of an observational proposal is an integral part
of this project. Experience with laboratory techniques is
Please note that the ESA projects are only available for students from ESA member or affiliate states (Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, The Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland, the United Kingdom, and Canada). Students from Cyprus, Estonia, Hungary, Latvia and Slovenia (affilliate members) can also apply for ESA projects.
Steffi Yen and her advisor, Adam Muzzin, presented a poster at the American Astronomical Society (AAS) winter meeting in Washington DC, "Searching for the Most Distant Galaxy Clusters". See here.
Fiona Thiessen and her advisor Sebastien Besse submitted a paper on Lunar surface composition and lava flows (figure below).
Conny Weber worked with Agnes Kospal on infrared variability of young stars in Chamaeleon which featured on a poster at the "The Universe Explored by Herschel" conference in Noordwijk (conference website). See the poster here.
Figure of the submitted paper by Fiona Thiessen, students of the LEAPS 2013 class. (a) M3 color composite image of the Imbrium basin (red: IBD1000, green: IBD2000, blue: R750 nm). Numbers indicate the basalt units mapped in this work. Large and spectrally bright craters are mapped separately in grey and were excluded from the basalt units. The surrounding highlands and kipuckas inside the Imbrium basin are also shown in grey. Dark strips correspond to portion of the lunar surface not observed with M3 using OP1B. (b) Eratosthenian basalt flows from Schaber  with flow phases I-III.
The 2013 LEAPS students (and some supervisors) on their visit to the Westerbork Radio telescope in Dwingeloo, the Netherlands.