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The Leiden/ESA Astrophysics Program for Summer Students (LEAPS) 2022

Applications for LEAPS 2022 are closed, and the selection process is completed.


LEAPS is an opportunity for students with an interest in astronomy and astrophysics to perform a 10 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 most past participants have been senior-undergraduate or masters' students who are enthusiastic about research in astrophysics.

We would like to use LEAPS as an opportunity to increase the diversity of researchers in Astronomy as we understand that successful science is supported by this. The Leiden projects are funded by a mix of grants and 50% of these grants are only available to students from historically underrepresented countires.

Students are selected for the program based on their academic achievements and research potential. Each applicant has the opportunity to choose up to two projects of interest, and they are selected by project advisors based on what they indicate their scientific interests and experience to be. Research at Leiden Observatory and ESA takes place on a diverse array of topics (see below for LEAPS 2022 projects), 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.

The LEAPS 2022 program will run in-person for 10 weeks from June 6 - August 12, 2022.

Leiden Observatory

Leiden Observatory (located in the Huygens and Oort buildings, Niels Bohrweg 2, Leiden) 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 ESA’s largest establishment, and its technical and organisational hub. 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.

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

Applications for LEAPS 2022 are now closed, and the selection process is now completed.

The program is open to all international students provided they are not currently enrolled in a Ph.D. program. For ESA projects (Type of project: ESA), in case of equivalent qualifications, preference will be given to nationals of one of the following ESA member states and cooperating states: Austria, Belgium, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Luxembourg, The Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland, and the United Kingdom plus Canada, Latvia, Lithuania, and Slovenia. The working language of the observatory is English, and students should be sufficiently proficient in English to perform a research project.

Applications for the LEAPS program require that you select two projects from the Research Project list that you are most interested in working on. The Research Project list for the LEAPS 2022 program were posted on January 15, 2022. Please note that this list may be updated after this date. The submission page will require the creation of a username and password. You will also be required to submit the following documents (in PDF format):

  • A one-page document describing your research interests
  • A transcript (grades)
  • A curriculum vitae (optional)

You will be asked to provide details of one person who can provide a letter of reference. Please see FAQ for more information.

Once you have submitted your 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.

If you have any questions about the application process or the program, please consult the Frequently Asked Questions page. If you have any questions that are not answered on the FAQ page, please .

Research Projects, Categories, and Supervisors

Project list for LEAPS 2022 (Last updated January 15, 2022):

Modelling the impact of metallicity on magnetic activity and exoplanetary habitability (ESA)


Keywords: Stellar activity, exoplanetary habitability

More info
Many factors determine whether an exoplanet is habitable. A key question is whether the exoplanet can retain its atmosphere over evolutionary time-scales. One way that planetary atmospheres can be eroded is by magnetic activity from the host star, such as X-ray or extreme ultraviolet radiation, in a process known as photoevaporation. Determining the levels of activity that a star has over its lifetime is therefore important to the topic of exoplanetary habitability. Ultimately, the activity level of a star should depend on its fundamental parameters such as its mass, rotation period and metallicity. The dependence on mass and rotation are already well established but the dependence on metallicity is much more uncertain. However, recent advances are now providing better constraints on the relationship between metallicity and activity. The goal of this project will be to incorporate these new results into numerical models that predict how the magnetic activity level evolves over the lifetime of a star. This will allow us to precisely determine how metallicty affects activity evolution in low-mass stars as well as the implications for exoplanetary habitability.

Star-planet interactions at radio wavelengths


Keywords: Star-planet interactions, radio emission, stellar magnetism, stellar winds

More info
Recent radio observations of solar-like stars may be indicative of interactions between the star's magnetic field and an undiscovered exoplanet. If these signals are of a star-planet origin, understanding and predicting them is key to inferring the properties of the planet and its respective orbit. Detection of such interactions can also provide a wealth of information about the outflowing stellar wind plasma, which in turn has consequences for the habitability of orbiting planets. In this project, the student will utilise Python code to explore these interactions in 3D. The main goal of this project is to determine what combination of the geometries of the magnetic field of the star and the planetary orbit provide the most favourable conditions for such interactions to be detected with current-generation radio telescopes. The ability to interpolate and manipulate arrays in Python efficiently is desirable.

Searching for oscillations in stellar flare emission - a bridge to understand the solar-stellar connection (ESA)


Keywords: Solar flares, stellar flares, time-series analysis, data-analysis

More info
Solar flares are enormous releases of magnetic energy that occur in the solar atmosphere, and can have significant adverse effects on the near-Earth environment, impacting the technological infrastructure that modern society depends on. They are the largest physical phenomenon in our solar system, increasing solar output across the entire electromagnetic spectrum. Similarly, flares can occur on other stars (for example red dwarfs) and such stellar flares are typically far more energetic than solar flares. These stellar flares could, in fact, be the main factor triggering or depleting life around other stars. A common feature of both solar and stellar flare emission is the presence of pulsations and oscillatory behaviour, known as quasi-periodic pulsations (QPPs). These pulsations have periods that range from fractions of a second to several minutes. On the Sun, recent studies combined imaging and time-series observational data to show that QPPs provide information on the properties of the associated active region. They also determined scaling laws relating the pulsation characteristics to physical properties of the flaring region. By searching and characterising QPPs in stellar flare emission, we can exploit the solar-stellar connection to perform stellar coronal seismology - using what we know about solar QPPs to diagnose the flare region properties of stellar flares. The LEAPS researcher will receive a large sample of stellar flares observed by NASA’s Transiting Exoplanet Survey Satellite (TESS) mission with high 20s time-sampling, and analyze it in more detail to search for QPPs. They will determine their prevalence, dependence on source star properties, and to identify if there are consistent scalings between solar and stellar flare QPPs. Experience with a computer programming language is required. In particular, experience with Python will be a benefit.

Exploring the connection between star formation and metallicity locally in low-mass galaxies (ESA)


Keywords: galaxies, metallicity, galaxy evolution, interstellar medium, integral-field spectroscopy

More info
Galaxies continuously undergo chemical evolution regulated by star formation, the infall of metal-poor gas and the outflow of enriched material that was processed in stars. The metallicity of the interstellar medium is therefore a key quantity to be considered when we want to understand the cycle of metals in galaxies. The fundamental mass-metallicity relation connects metallicity to galaxy mass and star formation rate finds that more massive galaxies are more enriched, but show less star formation. This relation has been explored with large samples of galaxies, but modern day integral-field spectroscopy (IFS) now allow us to study the complex interplay between metallicity and star formation locally in individual galaxies. The goal of this project is to explore the local fundamental mass-metallicity relation in a sample of low-mass galaxies for which photometric data from the Hubble Space Telescope and MUSE IFS data are available. The student will derive key properties from this data such as emission line fluxes, gas metallicity, star formation rate densities and stellar metallicities to compare the local fundamental mass-metallicity relation with previous global measurements from the literature, which will be essential to better understand the chemical evolution in galaxies. Prior experience with python would be beneficial.

On the rocks: silicate mineralogy in planet-forming disks


Keywords: planet-forming disks, dust, silicate mineralogy, modelling

More info
Silicates are a major constituent of dust in planet-forming disks, and the most important building blocks of terrestrial planets. The evolution of dust through grain growth is the first step of planet formation. The dust content of disks is inherited from the parent molecular cloud, but during the disk's lifetime it undergoes reprocessing, including crystallization, grain growth, and mineral alteration. Dust chemical models predict a rich inventory of minerals in disks, from which only a handful are detected observationally so far. Observations also indicate that the dust composition of the inner au can drastically differ from that of the rest of the disk. The physical origin for this is still unclear: while thermal processing by the stellar radiation is likely to be important, other factors, such as the effect of planets or direct condensation from gas-phase, may also play important roles. This research project aims to address some of these questions by (1) using available codes to model the radial dependence of the dust composition in realistic disk environments, and (2) create synthetic infrared observations that can be compared to actual data. The latter include archival spectroscopic data from the Spitzer Space Observatory, and (archival and new) data from the Very Large Telescope Interferometer (MIDI and MATISSE).

Tailed radio galaxies at sub-30 MHz frequencies - a unique diagnostic of clusters

Supervisor: Erik Osinga & Reinout van

Keywords: radio astronomy, galaxy clusters, AGN, calibration

More info
Tailed radio galaxies, often found in galaxy clusters, are some of the most exotically shaped radio sources, occasionally showing extreme bending of the jets and having sizes up to a Megaparsec. The long tails of the radio sources are unique probes of both the intracluster medium that is affecting the morphology of the radio emission and the nuclear activity of the host galaxies on timescales of hundreds of millions of years. At the endpoints of the tails, we probe the oldest population of relativistic electrons with extremely steep spectra, that can only be observed at the very lowest frequencies. LOFAR is the only radio telescope in the world that can observe below 30 MHz with a resolution <30''. For this project, we have observations available of various famous tailed radio galaxies in galaxy clusters from 10-58 MHz. The aim of the project is to reduce these observations using calibration scripts developed by the LOFAR group. This will allow the student to study for example the nuclear activity history of the host galaxies, emission mechanisms in the tails and the relation of radio tails with other diffuse radio sources in the clusters.

Source to sink systems, exploring the relationship between aeolian and fluvial features in Oxia Planum (ESA)


Keywords: Mars, ExoMars 2022,Remote sensing, Aeolian, Fluvial, Remote sensing

More info
Mars has not always been the cold, dry, red planet we see today. Remote sensing missions hasve revealed that billions of years ago the planet had a much denser atmosphere and liquid water. This raises the tantalising question - did these environments support life? In September 2022, the ExoMars “Rosalind Franklin” rover will travel to a region of Mars called Oxia Planum, a plain located at an outlet of the Cogoon Vallis drainage system. The site records a rich aqueous history in the Noachian (~4 Ga ago) in the form of clay-bearing sedimentary rocks: a fluvio-deltaic fan system and layered deposits that have undergone hydrothermal alteration (Quantin-Nataf et al., 2019). Wind-driven (aeolian) features such as dunes, ripples, and ridges have also shaped this landscape in the recent and ancient past. The goal of this project is to investigate the fluvial and aeolian features at Cogoon Vallis and explore how these may have interacted. This will shed light on the paleo-coastline and tell us what the Rover might find there when it lands in 2023. Using multiple datasets and Geographic Information Systems (GIS) software, tThe student will explore source to sink systems and establish the relationship between the fluvial and aeolian features in Oxia Planum. This will Shedding light on the paleo-coastline and build onhighlighting our understanding of what we expect the rover to see might find there when it lands in 2023 and may shed light on the coastline of Mars’ paleo-ocean.

Sublimating ices feeding forming planets


Keywords: Protoplanetary disks, Astrochemistry, Planet Formation, the Atacama Large Millimeter array

More info
New planetary systems are made from the dust and gas in the rotating disks around young stars. Observations of these planet-forming disks with the Atacama Large Millimeter Array (ALMA) can be used to learn about the planet-formation process. In particular, ALMA can trace the composition of the gas available to be accreted by planets. Simple molecules can be used to trace the elemental abundance ratios in the disk gas and this can be linked to the composition of the observed exoplanet population. Complex molecules can be used to diagnose the importance of inheritance from earlier stages of the star formation process. Furthermore, the detection of these potentially prebiotic molecules in planet-forming disks sheds light on how life originated in our solar system. The student will work with new ALMA data of different gas tracers in a protoplanetary disk that exhibits structures in the dust and gas and has planet candidates. This observational project will focus on a particular family of molecules which will be chosen depending both on the upcoming data and student's interests.

Chemical modeling of methanol - a potential shock tracer in extragalactic environment


Keywords: Astrochemistry, Nearby galaxies, ISM, AGN

More info
Methanol can be formed efficiently in cold environments (12-20K) through repeated hydrogenation of CO on ice grains (Fuchs et al., 2009). UV radiation and cosmic rays can desorb the methanol formed on ices into the gas phase. In the absence of a radiating energy source, the methanol on ices can be evaporated through sputtering in mildly shocked regions. If the shocks are fast enough, however, the methanol can be destroyed in the process (Suutarinen et al., 2014). In other words, methanol is a potential good tracer of slow shocks (v_s ~ 20 km/s), in differentiating from fast shocks (v_s ≥ 50 km/s). We propose to work with one summer student in performing chemical modeling with our in-house shock and gas grain chemical model UCLCHEM (Holdship et al. 2017), to investigate the origin of the methanol emission by also incorporating UV irradiation and cosmic rays which may also be strongly affecting methanol abundances in the ISM. This LEAPS project will be part of our investigation of methanol as a tool to reconstruct the shock history in the circumnulear disk (CND) of a nearby AGN-host galaxy, NGC 1068.

AGN size distribution in the Elais-N1 field


Keywords: Radio, AGN, LOFAR, size distribution

More info
The study of active galactic nuclei (AGN) has been accelerated with the development of radio astronomy since the 1950s, and becomes a focus of observational effort in every frequency band. The goal of the project is to explore the size distribution of radio AGNs in the Elais-N1 (European Large Area ISO Survey North1) field with LOFAR images and catalogue products. With highest ever resolution (1’’) image of Elais-N1 field at 144MHz, measuring the AGN sizes would produce an accurate AGN size distribution of this field. As a result, the age distribution of these AGNs can be constrained, which would further our understanding of AGN feedback. The student would be able to access the Elias-N1 field LOFAR image with the best resolution at 144 MHz so far, and identify both low- and high-excitation AGNs through image cross-matching with the LOFAR LoTSS survey catalogue. The student will derive key properties of AGNs from the catalogues and images such as flux density, redshift, luminosity and size, in order to probe the relation between AGN power and size. If time permits, a comparison with the existing models from the literature would be conducted, which would be essential to better understand the age distribution of AGNs in the Elais-N1 field. Prior experience with python would be beneficial.

Molecular Gas and Star Formation in Jellyfish Galaxies


Keywords: Galaxies, Galaxy Clusters, Star Formation, the Atacama Large Millimeter/submillimeter Array

More info
Galaxy clusters are the most extreme environments in the Universe, consisting of thousands of galaxies orbiting through a common dark matter halo. The cluster environment has a strong impact on star formation activity in member galaxies, with cluster galaxies tending to be gas-poor with little ongoing star formation (known as quenched). A likely cause of this star formation quenching is a process known as ram pressure stripping (RPS), which can remove star-forming gas from galaxies as they orbit through their host cluster. In extreme cases, known as jellyfish galaxies, long tails (or tentacles) of stripped gas is observed behind cluster galaxies undergoing RPS. This project will make use of observations from the Atacama Large Millimeter/submillimeter Array (ALMA) of the jellyfish galaxy IC 3949 in the nearby Coma cluster, to explore the effect of RPS on the spatial distribution of molecular gas. It is predicted that ram pressure will increase gas densities along the leading edge of jellyfish galaxies, however, observationally this is not well constrained. The project will consist of imaging molecular line data from ALMA, including the CO(J=1-0) and the HCN(J=1-0) transitions that trace bulk molecular gas and dense molecular gas in galaxies. The student will analyze the spatial distribution of CO and HCN emission to test for evidence of enhanced gas densities on the leading edge of IC 3949. The student will also explore the relationship between molecular gas and star formation rate (the Kennicutt-Schmidt Relation) for an extreme galaxy undergoing RPS. Project also supervised by Sarah Leslie.

The infrared and radio emission of distant galaxies in COSMOS-XS


Keywords: galaxies, starformation, multiwavelength, surveys

More info
The infrared and radio continuum luminosities are observed to be closely related in star-forming galaxies despite the fact that infrared radiation comes from the thermal radiation of dust heated by stars and radio synchrotron emission comes from non-thermal processes (cosmic rays accelerated by supernovae remnants). Even after decades of effort, this tight correlation is still not well understood, but it is used as evidence that radio continuum emission can be related to the star formation rate of galaxies. Recent progress has been made by careful analysis of large galaxy surveys, and there is now evidence that the infrared--radio correlation is not the same for all galaxies, but varies with mass. Theories also predict a change in the infrared--radio correlation with redshift, but observations do not support this. This LEAPS project aims to quantify how the infrared--radio correlation varies with galaxy stellar mass and redshift by using the deepest radio and infrared data available in the COSMOS field. Professor Hodge?s group at Leiden has led the COSMOS-XS survey, providing deep 3GHz radio data that, when combined with the latest multiwavelength data from the COSMOS collaboration, will allow us to detect faint low-mass galaxies at higher redshift than previously possible. A better understanding of the processes responsible for the radio emission in star-forming galaxies will be critical for interpreting data from future surveys, such as those with the international Square Kilometer Array. Project also supervised by Ian Roberts.

Investigating the molecular environment around supernova remnant G350.0-0.2


Keywords: supernova remnants

More info
We say that supernova remnants (SNRs) are the result of an interaction between an exploded star and its surrounding medium. In reality, SNRs are shaped by the circumstellar medium (CSM) that their progenitor stars sculpted during their lifetimes, the nature of the supernova (SN) explosion, the presence of a compact object, the ambient interstellar medium (ISM), and the local magnetic field structure. These physical conditions result in a SNR structure that shows complexity on many scales, but their relative contributions to the properties of the SNR are difficult to assess. This project will consist of analysing APEX 12CO J=2?1 and 13CO J=2-1 observations, to search for line broadening due to shock perturbation and bright 12CO emission due to heating, in order to (a) ascertain whether G350.0-0.2 is associated/interacting with neighbouring molecular clouds and whether these could be responsible for its large-scale structure and (b) find evidence in the molecular material for the mass-loss history of G350.0-0.2's progenitor star, as well as estimate its mass. These observations are part of a broader project aimed at understanding the morphology of shell/wing-shaped supernova remnants.

Astrophysics / Cosmology TBD


Keywords: TBD

More info

Past LEAPS Successes

LEAPS 2021 was a huge success! Due to the COVID-19 pandemic the summer school was held virtually and we had 22 students from all over the globe. Projects ranged from studies of solar system objects comet 67P and Mars, to physical and chemical tracers of star formation, protoplanetary disks, studies of exoplanets, and finally to observations of distant galaxies. See below the group photo from our students final presentations.

The LEAPS 2019 cohort had a great summer in Leiden and are already starting to share their research results with the world.

  • Danielle Rowland (supervised by B. Ribeiro and A. Paulino-Afonso) presented her research with a poster at the 2020 American Astronomical Society meeting. See here.
  • Lorena Acuña presented exoplanet atmospheric transmission spectra she obtained following her research on "Exploring the clearness/cloudiness of the atmosphere of gas giant exoplanets" in a poster at the ARIEL Science, Mission & Community 2020 conference held at ESA/ESTEC in January 2020.
  • and more publications are on the way!

LEAPS 2015 was a great success! Twenty-two students from four continents spent their summer in Leiden doing astrophysics research.

  • Joshua Borrow (with supervisor Pedro Russo) published a paper on astro-ph entitled "A Blueprint for Public Engagement Appraisal: Supporting Research Careers."
  • Lukasz Tychoniec (supervised by John Tobin) presented his research at the Polish Astronomical Society Summit, and his research already contributed to one published paper and he is preparing a paper on the full results.
  • Tessa Wilkinson (supervised by Anna-Lea Lesage) presented her research at the 2016 American Astronomical Society meeting.
  • Jeremy Dietrich (supervised by Christian Ginksi) submitted a paper to MNRAS "Archival VLT/NaCo multiplicity investigation of exoplanet host stars".
  • Maria Vincenzi (supervised by Carlo Manara) presented a poster at the workshop: "The accretion/outflow connection in YSOs" at ESTEC in October and a paper is in preparation.
  • Hope Boyce (supervised by Nora Lutzgendorf) presented a poster at the Canadian Conference for Undergraduate Women in Physics and a paper is in preparation.

The 2013, and 2014 groups of LEAPS students also performed very well and the first scientific publications are out!

  • Ryosuke Goto and his advisor Sean McGee published a paper on galaxy formation in the Monthly Notices of the Royal Astronomical Society on his LEAPS project; "The stellar mass function and efficiency of galaxy formation with a varying initial mass function". See here.
  • 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.
  • Hannah Harris, a 2014 LEAPS student, and her advisor Pedro Russo published a paper in the Space Policy Journal, "The Influence of Social Movements on Space Astronomy Policy." See here.
  • Saul Kohn (now a PhD student at UPenn) and his advisor David Sobral published a paper in Monthly Notices of the Royal Astronomical Society on his LEAPS project: "The most luminous Halpha emitters at z~0.8-2.23 from HiZELS". See here (link here).
  • LEAPS student Michael Hammer (from Cornell University) and his adviser Lucie Jilkova studied close stellar flybys that lead some stars to lose parts of their circumstellar discs. Using simulations in the AMUSE framework (www.amusecode.org), they showed that if the two stars approach each other close enough, part of the disc lost from one star can be transferred to the other one. These close encounters can happen shortly after stars form when many stars are clustered together. They further showed that even our Solar System might have experienced such an interaction and stolen some material, which is now orbiting in its outer parts, from another star. Michael presented a poster on the results of his LEAPS project on the 225th AAS meeting. The project eventually resulted to publication in an international refereed journal, which led to several press releases, for example: New Scientist, Scientific American, Universe Today.

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 [1973] with flow phases I-III. leaps2015 @ ESTEC

ESTEC group picture (joint tour with ASTRON summer school).

leaps2015 @ LOFAR

The rain could chase us away from LOFAR! (not quite drenched yet in this picture).

The 2013 LEAPS students (and some supervisors) on their visit to the Westerbork Radio telescope in Dwingeloo, the Netherlands.