Astrophysics seminar

Last modified by Till Sawala on 2024/12/12 14:43

Tähtitieteen seminaari / Astrophysics seminar

The seminar programme is organised by Till Sawala. If you would like to propose a speaker, please email: till.sawala@helsinki.fi

The seminar usually takes place on Fridays from 10:15 - 11:15, in A 315 (HIP seminar room), Physicum, Kumpula Campus, and remotely via zoom at the following link:

https://helsinki.zoom.us/j/65334904610?pwd=S2ZqYVpvQXVuTGNhVlJTbVczZlBwdz09

Please check this website for updates or different starting times!

Next seminar: Friday, December 13, 10:15, Olavi Kiuru (University of Helsinki): "Compton scattering in ultra-strong magnetic fields"

Abstract: Quantum electrodynamic processes in ultra-strong magnetic fields play a vital role in emission spectra of neutron stars. However, these processes are not well understood. In the vicinity of magnetars, i.e. neutron stars with very strong magnetic fields, the strength of the magnetic field can reach up to 10^15 Gauss. The strong magnetic field quantizes the electron energies into Landau levels.

In this work, we have studied the effect of the strong magnetic field on the scattering cross section of Compton scattering. We find that the Landau levels play a crucial part in determining the shape of the cross section. With the calculational methods that we are developing, we hope to be able to calculate the cross sections of all relevant QED processes in ultra-strong magnetic fields, which would allow us to simulate the plasma around neutron stars.

Program Autumn 2024

3.9. Yasin Qasi (Newcastle University): "Nonlinear States of the Magnetic Buoyancy Instability"
27.9. Balint Seli (Konkoly Observatory, Hungary): "Stellar flare shapes with TESS
4.10. Vadim Kravtsov (University of Turku): "Probing the physics of black hole and neutron star X-ray binaries with polarimetry"
11.10. Mikael Granvik (University of Helsinki): "Understanding the population of near-Earth objects through physico-dynamical models and telescopic surveys"
17.10. Timothy Heaton (University of Leeds): "Radiocarbon Dating: The essential clock to measure the past"
08.11. Jens Jasche (University of Stockholm): "Tracing Cosmic Origins: Towards a Digital Twin of the Universe"
15.11. Enrico Congiu (ESO): "The MUSE view of the Sculptor"
22.11. Mika Juvela (University of Helsinki): "Radiative transfer modelling of Taurus and Orion clouds"
13.12. Olavi Kiuru (University of Helsinki): "Compton scattering in ultra-strong magnetic fields"

Past program Spring 2024

19.1. Joonas Nättilä (Flatiron Institute/Columbia University): "Neutron Star Weather Forecasting"
26.1. Núria Miret-Roig (University of Vienna): "Synchronising stellar clocks. A new observable for probing star formation and dispersion"
9.2. Sarah Bird (China Three Gorges University): "Milky Way Mass with K Giants and BHB Stars Using LAMOST, SDSS/SEGUE, and Gaia"
16.2. Eric McLennan (University of Helsinki): "Thermal Processes on near-Sun Asteroids: Observations and Models"
23.2. Guilhem Lavaux (Institut d'Astrophysique de Paris): "Machine learning boosted cosmological inference"
1.3. Raffaele Gratton (INAF): "How frequent is the Solar System?"
22.3. Emma Thomas (University of Leicester): "Into the Unknown: Observing infrared aurorae of Uranus"
5.4. Till Sawala (University of Helsinki): "Revealing the Galactic potential with expanding star clusters"
10.4. Jenny Wagner (BASIC): "Lensing of '69 -- Free gravitational lensing from its heuristic models"
26.4. Job Vorster (University of Helsinki): "VLBI Water Maser Monitoring During the Onset of the Accretion Burst in NGC6334I"
3.5. David Benisty (University of Cambridge): "Constraining Dark Energy from the Local Universe"
17.5. Jehanne Delhomelle (University of Helsinki / Toulouse): "The future of the Local Group"
17.6. Antti Rantala (MPA Garching): "Hierarchical star cluster assembly boosts massive black hole seed formation"
26.7. Radhika Chirakkara (The Australian National University): "Magnetic field in galaxy clusters (with Hybrid particle-in-cell simulations)"

Past program Autumn 2023

8.9. Till Sawala (Helsinki): "The Timeless Timing Argument"
15.9. Elisabeta Lusso (Florence): "What we can (still) learn from the non-linear X-ray to UV relation in AGN"
22.9. Karri Muinonen (Helsinki): "Scattering of light by cosmic dust particles using parameterization"
29.9. Antti Penttilä (Helsinki): "Modeling the polarimetric observations of the Didymos asteroid"
4.10. Sandrine Lescaudron (Institud d'Astrophysique de Paris): "Dynamical friction of a massive black hole in a turbulent gaseous medium"
6.10. Alex Rawlings (Helsinki): "Uncertainty in SMBH binary eccentricity is unavoidable"
13.10. Katja Fahrion (ESA): "Nuclear star cluster formation in massive and dwarf galaxies"
27.10. Maria Stone (Turku): "Observational view of galaxies in Type I quasar fields at redshifts 0.1<z<0.5 and its implications to AGN triggering and galaxy evolution"
3.11. Haonan Zheng (Durham): "Dark Matter Mini-halo Abundance and Annihilation Signals Under Baryonic Impacts"
10.11. Federico di Vruno (SKA Observatory): "Dark and Quiet Skies and satellite constellation interference" slides available
15.11. Bingqing Sun (Massachusetts Amherst): "The role of spiral arms in Galaxies"
24.11. Christopher Tiede (Copenhagen): "Orbital evolution and observational signatures of massive binaries accreting from circumbinary disks"
1.12. Jessica Hislop (Helsinki): "How clustered stellar feedback drives galactic scale outflows"
5.12 Tomáš Šoltinský (Tata Institute of Fundamental Research): "Prospects of statistical detection of the 21-cm forest by the uGMRT"
8.12. Elina Lindfors (Turku): "The Mystery of Cosmic Neutrinos"
15.12. Maarit Korpi-Lagg (Aalto) : "Dynamo instabilities in stellar convection zones: implications for dynamics and dynamos"

Past program Spring 2023

13.1. Axel Runnholm (University of Stockholm): "Probing the Epoch of Reionization with Lya - laying the foundations at low redshift "
17.1. Jan Kára (Charles University Prague): "Doppler tomography of the cataclysmic variable IX Velorum"
20.1. Christopher Berry (University of Glasgow): "Understanding the evolution of binary black holes"
3.2. Mireia Montes (Instituto de Astrofísica de Canarias): "How the intracluster light is going to change your life!"
10.2. Stefano Andreon (INAF-OA Brera): "The inside-out growth of galaxy clusters: reaching the virial radius in Abell 2244"
17.2. Till Sawala (University of Helsinki): "Distinct distributions of elliptical and disk galaxies as a ΛCDM prediction"
24.2. Sohan Ghodla (University of Auckland): "Influence of accretion on stellar and compact remnant evolution"
3.3. Richard Brooks (University College London): "ΛCDM survives another day: Origins of the asymmetry in the ALFALFA survey"
17.3. Johanna Hartke (University of Turku): "Tracing halo and intra-cluster light assembly with planetary nebulae"
24.3. Bibiana Prinoth (Lund Observatory): "Exploring the atmosphere of the ultra-hot Jupiter WASP-189 b"
31.3. Alberto. J. Castro-Tirado (Institute of Astrophysics of Andalucía): "The Burst Observer and Optical Transient Exploring System in the Multi-Messenger Astronomy Era"
14.4. Mika Juvela (University of Helsinki): "Structure of star-forming clouds: methods and measurements"
21.4. Thomas Hackman (University of Helsinki): "Magnetic fields on solar-type stars"
28.4. Dipto Mukherjee (Carnegie Mellon University): "Exploring the Dynamics of Massive Black Hole Mergers in Relaxed Nuclear Star Clusters"
5.5. John Regan (Maynooth University): "Black Hole Formation Pathways and Observational Signatures"
15.5 Thorsten Naab (MPA Garching): "Towards a complete model of the star forming interstellar medium"
16.6. Arif Babul (University of Victoria): "Modeling the Formation and Evolution of Massive Galaxies in the Cosmos: Successes & Opportunities"

Past program Autumn 2022

9.9. Ruby Wright (ICRAR & Flatiron Institute), "An orbital perspective on the starvation, stripping, and quenching of satellite galaxies in cosmological simulations"
16.9. Till Sawala (University of Helsinki), "The Local Group's mass: probably not more than the sum of its parts"
7.10. Shourya Khanna (INAF Torino), "Galactic dynamics with Gaia DR3: A new resonance-like feature in the outer disc of the Milky Way"
14.10. Franco Vazza (University of Bologna), "The simulated and observed magnetism of the cosmic web"
20.10. Simon Portegies Zwart (Leiden University), "The unpredictability of relativistic stellar clusters and the paradox of infinitesimal granularity"
4.11. Benne Holwerda (University of Louisville), "Looking At the Distant Universe with the MeerKAT Array LADUMA"
11.11. Petra Nianqi Tang (University of Auckland), "Predicting gravitational wave signals from galactic binary populations of a Milky Way-like galaxy for LISA"
18.11. Mikko Pöntinen (University of Helsinki), "Detecting asteroids with convolutional and recurrent neural networks"
25.11. Joanna Drazkowska (MPI for Solar System Research), "Rewriting the planet formation theory"
2.12. John Wu (Space Telescope Science Institute), "Astronomy Re-envisioned: Investigating the Physics of Galaxy Evolution with Machine Learning"
9.12. Event in celebration of Juhani Huovelin (15:00)
16.12. Tero Hiekkalinna (University of Helsinki / THL), "Light from the Darkness - Deep Space Astrophotography"

Past program Spring 2022

14.1. Job Vorster (North West University), "Accretion bursts: a global observational effort in massive star formation studies"
21.1. Till Sawala (University of Helsinki), "The Plane of Milky Way satellites - the end of ΛCDM?"
28.1. Francesco Rizzuto (University of Helsinki), "Collisions in compact star clusters and formation of massive Black Holes"
4.2. Laura Sberna (Albert Einstein Institute), "The calm after the storm: black hole ringdown beyond linear perturbation theory"
11.2. Tuomas Kangas (Stockholm), "The structure of the SN 1987A remnant"
18.2. Pascale Jablonka (EPFL Lausanne), "Looking for and into the galaxy building blocks"
25.2. Alejandro Benitez-Llambay (University of Milano-Bicocca), "Dark and late-forming galaxies: probing ΛCDM at the edge of galaxy formation"
4.3. Sambatra Andrianomena (University of Cape Town), "Leveraging Machine Learning and Simulation in preparation for the era of big data in Astronomy"
25.3. Sanna Damsted (University of Helsinki), "Role of substructure in galaxy cluster scaling relations"
1.4. Mika Juvela (University of Helsinki), "Simulations and synthetic interferometry observations of a high-mass star forming cloud"
8.4. Antti Penttilä (University of Helsinki) "Blender/Python testbed for asteroid imaging and camera performance simulations"
22.4. Leo Burtscher (University of Leiden), "Astronomy and the climate crisis"
29.4. Miikka Väisälä (Academica Sinica, Taiwan), "Pseudodisks in Star Formation"
13.5. Special seminar with Auni Somero (aeromon.fi) and Pauli Pihajoki, "Life and work beyond academia"

Past program Autumn 2021

17.9. Dimitrios Irodotou (University of Helsinki), "The effects of AGN feedback on the structural and dynamical properties of Milky Way-mass galaxies in cosmological simulations"
24.9. Aku Venhola (University of Oulu), "Low mass galaxies and their evolution in dense galactic environments - the Fornax cluster as a case study"
1.10. Jessica Hislop (Max Planck Institute for Astrophysics), "The challenge of simulating the star cluster population of dwarf galaxies with resolved interstellar medium"
8.10. Stephen Marsden (University of Southern Queensland), "The shared evolution of stars and planets"
15.10. Anne Virkki (University of Helsinki), "Characterizing Near-Earth Asteroids using the Arecibo Radar Observations"
22.10. Teemu Willamo (University of Helsinki), "Magnetic imaging of young solar analogues"
29.10. Achamveedu Gopakumar (Tata Institute of Fundamental Research, Mumbai): "Modeling gravitational wave signals from non-circular compact binaries"
5.11. Ioana Ciuca (University College London): "Unveiling missing hidden atomic physics using generative machine learning models" slides available to download here
12.11. Jyri Lehtinen (University of Helsinki): "Stellar magnetism across rotation and the HR-diagram"
19.11. Johan Fynbo (Niels Bohr Institute, University of Copenhagen) "Astrometric selection of Quasars"
26.11. Nikki Arendse (DARK, University of Copenhagen), "Cosmic dissonance: new physics or systematics behind the Hubble tension?"
3.12. Josh Borrow (MIT), "How to Simulate a Universe: The numerics and limitations of Cosmological Simulations"

Past Program Spring 2021

15.1 Sandra P. Treviño-Morales (Chalmers University of Technology, Sweden) at 11.15: Dynamics and fragmentation in Galactic filamentary structures
29.1 Toni Tuominen (University of Tartu, Estonia): An EAGLE view of the missing baryons
5.2 Akke Viitanen (University of Helsinki): Untangling X-ray AGN clustering through observations and semi-empirical models
12.2 Dimitrios Irodotou (University of Sussex, UK): Analysing the morphology of simulated galaxies and the effect of AGN feedback
19.2 Eric MacLennan (University of Helsinki): The Thermal and Dynamical History of (3200) Phaethon and (155140) 2005 UD
19.3 Mikko Tuomi (University of Helsinki): Planets orbiting M dwarfs in the Solar neighbourhood - The spectacular abundance of small planets orbiting M dwarfs based on radial velocity surveys
16.4 Emma Mannfors (University of Helsinki): Characterization of dense Planck clumps observed with Herschel and SCUBA-2
23.4 Thomas Pasini (Hamburg University): Radio galaxies in galaxy groups: kinematics, scaling relations and AGN feedback
30.4 Johannes Markkanen (Max Planck Institute, Germany): Scattering, absorption and thermal emission by dust: Application to the comet 67P/Churyumov-Gerasimenko
7.5 Karri Muinonen (University of Helsinki): Coherent backscattering by airless Solar System objects using Mueller matrix decomposition
21.5 David Korda (University of Helsinki): Helioseismic inversions for plasma flows

Past Program Fall 2020

18.9 Shihong Liao (University of Helsinki): The story of ultra-diffuse galaxies in the Auriga simulations
23.10 Mika Juvela: Modelling of Interstellar Medium
29.10 Neil Cornish (Montana State University): On the road to low frequency gravitational wave detection: NANOGrav at mile marker 12.5
30.10 Antti Penttilä: Asteroid taxonomy using neural networks
6.11 Joonas Uusitalo: Astronomical and terrestrial anomalies in natural archives
13.11 Heidi Lietzen (Tartu Observatory): Groups of galaxies as the evolving building blocks of the Universe
20.11 Charlie Mpetha (Liverpool University): Gravitational Redshifting of Galaxies in the SPIDERS Cluster Catalogue
27.11 John Regan (Maynooth University, Ireland): Pathways to Forming Massive Black Holes in the Early Universe
4.12 Stefano Andreon (Brera Observatory): Gas-poor clusters: what kind of beasts are they?
11.12 Julia Martikainen (University of Helsinki) at 11:00: Asteroid phase curve parameters and absolute magnitudes from Gaia photometry

Past Program Spring 2020

10.1 Ulrich Steinwandel (LMU Munich): Resolving ISM-physics in galactic scale simulations
17.1 Athanasia Toliou (Luleå University of Technology): Dynamical evolution of the Main Asteroid Belt in the primordial Solar System
31.1 Stuart McAlpine (University of Helsinki): Galaxy mergers in EAGLE do not induce a significant amount of black hole growth yet do increase the rate of luminous AGN
7.2 Till Sawala (University of Helsinki): Setting the Stage: Structure formation from Gaussian Random Fields
21.2 Joonas Herranen (University of Helsinki): Too plausible to be true? Centrifugal explosions of cometary dust by sunlight VS a zoo of observations
28.2 Eric MacLennan (University of Helsinki): Deciphering Space Weathering on Asteroids using Meteorite Analogs
13.3 Natalia Lahen (University of Helsinki): Simulating the formation of star clusters in a dwarf galaxy starburst resolved with individual massive stars
20.3 Neha Sharma (Kyung-Her University): Triggered star formation in molecular clouds
3.4 Tomas Kohout (University of Helsinki): Spectral Shock Darkening During Asteroid Collisions
15.5 Timo Väisänen (University of Helsinki): Light scattering in dense particulate media

Past Program Fall 2019

9.8. Habib Khosroshahi (IPM/INO): Galaxies and central engine; the role of group environment and dynamics
30.8. Hamid Mehdipour (Lahijan University): Cluster analysis of the solar system objects
6.9. Lauri Haikala (Universidad de Atacama): A mysterious dusty object in the Sa galaxy NGC3269
13.9. Antti Rantala (University of Helsinki): Galactic-scale N-body simulations with resolved small-scale gravitational dynamics: recent progress and future challenges
20.9. Matias Mannerkoski (University of Helsinki): Gravitational Waves from the Inspiral of Supermassive Black Holes in Galactic-scale Simulations
27.9. Peter Roelfsema (SRON): SPICA - a joint infrared space observatory
4.10. Peter Johansson (University of Helsinki): Post-Newtonian dynamical modelling of super-massive black holes in global large-scale simulations
11.10. Karri Muinonen (University of Helsinki): Asteroid lightcurve inversion using Bayesian inference
18.10. Teemu Willamo (University of Helsinki): Shapes of stellar activity cycles
1.11. Moses Mogotsi (South African Astronomical Observatory): Multi-wavelength Feedback studies in the Nearby Universe, featuring IRAS18293-3413 and friends
8.11. Alex Ho (University of Agder): The Extended N-Body Problem
15.11. Matthew Holman (Harvard-Smithsonian Center for Astrophysics): A Pan-STARRS and TESS Search for Distant Planets
22.11. Alberto Cellino (INAF Osservatorio Astrofisico di Torino): Asteroid Polarimetry: State of the art and Recent Achievements
29.11. Alexis Finoguenov (University of Helsinki): Largest spectroscopic catalog of X-ray galaxy clusters from SDSS-IV
13.12. Evgenij Zubko (Kyung Hee University): Polarimetry of two near-Earth comets of 2018: Fast variations of polarization in the 21P/Giacobini-Zinner coma and low P_max in C/2018 V1 (Machholz–Fujikawa–Iwamoto)
19.12. Anne Virkki (Arecibo Observatory): Arecibo Observatory planetary radar program

Past Program Spring 2019

22.1. Johan Comparat (MPE): Cosmology with eROSITA's active galactic nuclei
25.1. Jacob Ider Chitham (MPE): Optical follow-up of CODEX galaxy clusters with SPIDERS and Pan-STARRS
1.2. Ghassem Gozaliasl (University of Helsinki): BGG science in deep surveys vs. simulations
8.2. Hannu Kurki-Suonio (University of Helsinki): Euclid Cosmology Mission
15.2. Florian Käfer (MPE): Towards a characterization of X-ray galaxy clusters for cosmology
21.2. Miikka Väisälä (TIARA/ASIAA, Taiwan): Observational Signatures of Misaligned Magnetic Fields in Early Disk Formation and Their Time Evolution
25.2. Oleksiy Golubov (V. N. Karazin Kharkiv National University and University of Colorado Boulder): Light pressure forces on asteroids and YORP equilibria
1.3. Clotilde Laigle (University of Oxford): Observing the multi-scale cosmic web at high redshift and quantifying its impact on galaxy assembly
15.3. Oliver Müller (University of Strasbourg): Testing cosmological models with dwarf galaxies
22.3. Roberto De Propris (University of Turku): The Ultraviolet Upturn in Elliptical Galaxies
29.3. Guanglang Xu (University of Helsinki): A quick introduction to spherical wavelets and two relevant applications
5.4. John Regan (Dublin City University): Black Hole Formation in the Early Universe
10.4 Lankeswar Dey (University of Turku): The Nascent Field of Nanohertz Gravitational Wave Astronomy
12.4. Julia Martikainen (University of Helsinki): Asteroid surface composition by modelling light scattering
26.4. Grigori Fedorets (University of Helsinki): Discovering minimoons with LSST
3.5. Yirui Zheng (University of St. Andrews): Comparison of stellar populations of simulated and real post-starburst galaxies in ManNGA
6.5 Richard Ellis (University College London): The First Galaxies and Cosmic Reionisation
7.5 Richard Ellis (University College London): The Assembly History of Elliptical Galaxies
10.5 Joonas Herranen (University of Helsinki): Well-behaving dust and other small particles – an overview to scattering dynamics
15.5 Jürgen Blum (IGep, TU Braunschweig): What comets can tell us about planetesimal formation
24.5 Tuomas Savolainen (Aalto University): First M87 Event Horizon Telescope Results: Imaging the Shadow of the supermassive black hole
28.5 Eric MacLennan (University of Helsinki): Asteroid Surfaces in the Thermal Infrared
18.6 Matthieu Schaller (Leiden University): Towards exa-scale for cosmological hydro simulations: Challenges and (some) solutions in the SWIFT code

Past Program Autumn 2018

8.8. Colin Snodgrass (Open University, UK): It came from outer space: Interstellar visitor 1I/‘Oumuamua
10.8. Robert Nelson (Planetary Science Institute): Creating Planetary Regoliths in the Laboratory – What do Remote Sensing Observations tell us?
15.8. Moses Mogotsi (South African Astronomical Observatory): The Kinematics of SUNBIRD LIRGS
24.8. Lauri Haikala (Universidad de Atacama): ALMA observations of globulettes: formation sites of free floating planets?
4.9. Xiaobin Wang (Yunnan Observatories, Chinese Academy of Sciences): Physical studies of near-Earth asteroid (3200) Phaethon
5.9. Shenghong Gu (Yunnan Observatories, Chinese Academy of Sciences): Yunnan-Hong Kong wide field transit survey
14.9. Ellie Sansom (Curtin University): The Desert Fireball Network - Fireballs, Orbits and Meteorites
28.9. Stuart McAlpine (University of Helsinki): Growing black holes in the EAGLE simulation
12.10. Gastón Folatelli (Universidad Nacional de la Plata): The birth of a supernova
19.10. Jorma Harju (University of Helsinki): ALMA observations of a de-icing zone around a prestellar core
26.10. (teaching break)
1.11. Tuomo Salmi (University of Turku): Mass and radius constraints for neutron stars from X-ray timing, spectral and polarization observations
9.11. Pauli Pihajoki (University of Helsinki): Barycentric interpolation on Riemannian manifolds
14.11. Jan-Willem den Herder (SRON): High spectral resolution X-ray imaging with Athena: a new window on the hot and energetic Universe
30.11. Nico Krieger (MPIA): Zooming into the starburst environment of NGC253 and the Galactic Center
7.12. Mika Saajasto (University of Helsinki): A stellar cluster in formation: cloud G074.11+00.11
14.12. Thomas Hackman (University of Helsinki): Long-term monitoring of stellar spot activity

Past Program Spring 2018

5.1. (teaching break)
12.1. (teaching break)
19.1. Marius Cautun (University of Durham): Revealing Local Group mysteries using dwarf galaxies
26.1. Mauri Valtonen (University of Turku): The host galaxy of the BL Lacertae object OJ287
2.2. Antton Luoma (University of Helsinki): Parametric studies of galaxy structure and morphology using GALFIT
9.2. Till Sawala (University of Helsinki): The Local Group in Eight Figures
16.2. Göran Maconi (University of Helsinki): Experimental light scattering by small particles: orientation-controlled 4π levitating scatterometer
23.2. Karri Muinonen (University of Helsinki): Light scattering in dense random media of cosmic dust using incoherent interactions
2.3. Johannes Markkanen (University of Helsinki): Numerical solutions for light scattering by cosmic dust and planetary regolith
9.3. (teaching break)
16.3. Mika Juvela (University of Helsinki): Polarisation observations of an infrared dark cloud
23.3. Rudy Wijnands (University of Amsterdam): Probing dense matter physics using the cooling of accretion-heated neutron-star crusts
28.3. Lankeswar Dey (University of Turku): Calculating hereditary contribution to gravitational radiation from eccentric binary black hole in blazar OJ287
30.3. (good Friday)
6.4 Antti Penttilä (University of Helsinki): Multiple scattering modeling pipeline for spectroscopy, polarimetry, and photometry
12.4 David Buckley (South African Astronomical Observatory): "Observing Transients at SAAO and SALT"
13.4 Florent Leclercq (Imperial College London): Bayesian large-scale structure inference, likelihood-based and likelihood-free approaches
20.4. Jukka Nevalainen (Tartu Observatory): Finding the missing baryons
27.4. Jussi Ahoranta (University of Helsinki): FUV Guided X-ray studies of WHIM: The evidence in the sight-line towards the quasar 3C273
4.5. Till Sawala (University of Helsinki): The next 8 billion years of the Local Group
11.5. (teaching break)
25.5. Kirsi Lehto (University of Turku): Current topics in astrobiology
8.6. Jesús Escobar-Cerezo (University of Helsinki): Light scattering: an experimental and computational study of a lunar regolith analog
15.6. Guilhem Lavaux (IA Paris): Non-linear bayesian inference of cosmic fields in SDSS3 and 2M++ and their applications to nearby cosmology
20.6. Thorsten Naab (MPA Garching): High resolution galaxy evolution simulations with feedback from individual stars

Past Program Autumn 2017

22.8. Stefano Borgani (INAF - Astronomical Observatory of Trieste): Understanding Galaxy Clusters with Simulations
1.9. Joop Schaye (University of Leiden): Simulating the formation of galaxies
8.9. Christopher Haines (Osservatorio Astronomico di Brera): VIPERS: The decline and fall of the most massive star-forming galaxies since z~1
15.9. Klaudia Kowalczyk (Nicolaus Copernicus Astronomical Center, Warsaw): Modelling dwarf spheroidals with Schwarzschild methods
29.9. Urs Ganse (University of Helsinki): Vlasiator: Simulating the entire Earth's Magnetosphere in Kinetic Physics
6.10. Jorma Sakari Harju and Kimmo Lehtinen (University of Helsinki): Asteroid occultations of radio galaxies
13.10. Lucile Turc (University of Helsinki): The outer regions of the near-Earth's space and their role during solar storms
20.10. Joonas Nättilä (University of Turku): Probing the nuclear physics of neutron stars with astrophysics
24.10. Roberto De Propris (University of Turku): The New Bulge
27.10. Lauri Siltala (University of Helsinki): Asteroid mass estimation with Markov-chain Monte Carlo
2.11. Mordecai Mark Mac Low (Columbia University): Formation and Evolution of Giant Molecular Clouds: Gravity or Turbulence?
10.11. Lasse Liljedahl (University of Helsinki): The Effects of Supernova Feedback on Disk Galaxy Formation
17.11. Joachim Janz (University of Oulu/ FINCA): On the mass-size diagram of early-type galaxies and clues about the origins of low-mass early types
and Begoña Ascaso (Laboratoire Astroparticule & Cosmologie, Paris): Cluster cosmology with Euclid, LSST and J-PAS
24.11. Antti Rantala (University of Helsinki): Scouring the core of the early-type galaxy NGC 1600 with a supermassive black hole binary
8.12. Laura Zschaechner (Helsinki / FINCA): Gas Flows in Galaxies Part I: Emerging Observations and Modeling of Extra-planar Atomic and Molecular Gas in Nearby Galaxies
15.12. Anni Järvenpää (University of Helsinki): Mass Estimates of the Local Group

Past Program Spring 2017

27.1. Jimit Sanghvi (University of Turku):Evolution of low-mass quasars and environments of QSO pairs
3.2. Guilhem Lavaux (Institut d'Astrophysique de Paris): Cosmology with the Nearby Universe through full statistical reconstruction of wide galaxy surveys
10.2. Ronald Läsker (University of Turku): New aspects of the Black Hole scaling relations
17.2. Mikael Granvik (University of Helsinki): Near-Earth asteroids: from sources to sinks
24.2. David Martinez-Delgado (ARI Heidelberg): Stellar Tidal Streams in the halos of nearby spiral galaxies
3.3. Akke Viitanen (University of Helsinki): The Clustering of Active Galactic Nuclei in the COSMOS field
17.3. Minna Myllys (University of Helsinki): Solar Wind-Magnetosphere Coupling Efficiency and Polar Cap Potential Saturation
24.3. Pauli Pihajoki (University of Helsinki): Ray-tracing and polarized radiative transfer in General Relativity
31.3. Teemu Willamo (University of Helsinki): Magnetic activity of V889 Herculis
7.4. Peter Johansson (University of Helsinki): Rapid formation of supermassive black holes in close proximity to embryonic protogalaxies
21.4. Lucien Kuiper (SRON - Netherlands Institute for Space Research): The high-energy twilight zone of magnetars and rotation-powered pulsars
28.4. Claudia Maraston (University of Portsmouth): Stellar population models: from galaxy formation to cosmology
5.5. Wara Chamani (Aalto University): Turbulent gas accretion between supermassive black holes and star-forming rings in the circumnuclear disk
12.5. Olivier Ilbert (Laboratoire d'Astrophysique de Marseille): Galaxy stellar mass assembly from deep imaging surveys
2.6. Lauri Jetsu (University of Helsinki): General Model for Light Curves of Chromospherically Active Binary Stars
19.6. Xiaoyan Zhou (Earth, Planetary and Space Science, University of California, Los Angeles): Effects of Interplanetary Shocks on the Lunar Wake

Past Program Autumn 2016

9.9 Joonas Herranen (University of Helsinki): Dynamics of Interstellar Dust Particles in Electromagnetic Radiation Fields
16.9 Timo Väisänen (University of Helsinki): Towards a new kind of radiative transfer
23.9 Chris Collins (Liverpool John Moores University, UK): The properties and evolution of Brightest Cluster Galaxies
30.9 Maria Gritsevich (University of Helsinki): The recovery of the Annama meteorite and the Finnish Fireball Network
7.10 Mika Juvela (University of Helsinki): Graphic details of interstellar medium
14.10 Till Sawala (University of Helsinki): Shaken and Stirred: The Milky Way's Dark Substructures
21.10 Mike West (Lowell Observatory): Galaxy Birth, Death and Reincarnation
28.10 Mika Saajasto (University of Helsinki): Correlation of gas dynamics and dust in the Herschel field G82.65-02.00
4.11 Jorma Harju (University of Helsinki): Nuclear spin ratios as clues to the origin of deuterated ammonia in dense interstellar clouds
11.11 Ghassem Gozaliasl (University of Helsinki): Evolution of the central galaxies in X-ray galaxy groups over 9 billion years
18.11 Thomas Hackman (University of Helsinki): Observing Stellar Dynamos in Action
25.11 Antti Rantala (University of Helsinki): KETJU: Post-Newtonian supermassive black hole dynamics in galaxy simulations
2.12 Natalia Lahén (University of Helsinki): Simulating the fate of the Antennae galaxies
9.12 Antti Penttilä (University of Helsinki): Asteroid phase curve analysis with the H,G1,G2 photometric phase function
16.12 Viola Allevato (University of Helsinki): Clustering properties of AGN at different redshifts, scales and luminosities
20.12 Extraordinary Seminar Evgeniya Petrova (Ural Federal University, Ekaterinburg, Russia): Texture of Chelyabinsk LL5 meteorite

Past Program Spring 2016

11.1 Extraordinary Seminar Daniel Mackowski (Auburn University, Alabama): Electromagnetic scattering by discretely inhomogeneous, plane parallel media: direct simulation strategies using high performance computing
15.1 Extraordinary Seminar Bryce Bolin (Observatoire de la Cote d'Azur, Nice, France): Identifying asteroid family Yarkovsky V-shape
22.1 Jyri Lehtinen (University of Helsinki): Activity of young solar-type stars
29.1 Violeta Gonzalez (University of Durham): Issues with making galaxies in the computer relatively fast
5.2 Pauli Pihajoki (University of Helsinki): Black hole accretion disc impacts
12.2 Graham Smith (University of Birmingham, UK): Weak-lensing mass calibration of LoCuSS galaxy clusters and implications for "Planck Cosmology"
19.2 Mikael Granvik (University of Helsinki): Super-catastrophic disruption of asteroids at small perihelion distances
26.2 Peter Johansson (University of Helsinki): The formation of the first supermasssive black holes in the Universe
4.3 Johannes Markkanen (University of Helsinki): Fast solution for electromagnetic scattering by multiple targets
11.3 Teaching Break
18.3 Tomas Kohout (University of Helsinki): ASPECT CubeSat mission to a binary asteroid Didymos
25.3 Easter Break
1.4 Lauri Jetsu (University of Helsinki): Shifting Milestones of Natural Sciences: The Ancient Egyptian Discovery of Algol’s Period Confirmed
8.4 Elisabetta Micelotta (University of Helsinki): Dust Destruction by the Reverse Shock in the Cassiopeia A Supernova Remnant
15.4 Lauri Siltala (University of Helsinki): Asteroid mass estimation using Markov Chain Monte Carlo techniques
22.4 Guilhem Lavaux (Institut d'Astrophysique de Paris): New statistical methods in the analysis of the dynamics of Large Scale Structures
29.4 Julien Moreau (University of Helsinki): Shock-darkening in ordinary chondrites: Insight to numerical modelling and what it can tell us
6.5 Ascension Day Break
13.5 Jesús Escobar-Cerezo (Instituto de Astrofísica de Andalucía, Granada, Spain): Light scattered by dust particles in the solar system: an experimental and computational approach
1.6 Noelia Jimenez (University of St. Andrews, UK): Why galaxies care about Supernovae Type Ia?
3.6 Deborah Domingue Lorin (Planetary Science Institute, Tucson): Photometry of Mercury's surface: Perspectives from the Camera and Spectrometer on Board MESSENGER

Past Program Autumn 2015

4.9 Craig Sarazin (University of Virginia): Mergers, Shocks, and the Dynamical State of Clusters of Galaxies
11.9 Jussi Väliviita (University of Helsinki): Does dark energy decay to dark matter?
16.9 Extraordinary Seminar Seshadri Nadathur (University of Helsinki): The nature of voids: simulations, theory, and use in cosmology
18.9 Astronomy Seminar moved to 16.10
25.9 Seppo Mikkola (University of Turku): Regularisation of Few-Body Dynamics
2.10 Takayuki Tamura( ISAS/JAXA, Japan): X-ray spectroscopy of galaxy clusters with Suzaku and future ASTRO-H
9.10 Bo Reipurth (University of Hawaii): The Dynamical Evolution of Newborn Triple Systems
16.10 Karri Muinonen (University of Helsinki): Asteroid light curve inversion with Lommel-Seeliger ellipsoids
23.10 Adam Muzzin (University of Cambridge): The Formation of Galaxy Clusters and the Evolution of Their Galaxies at 0 < z < 2
30.10 No Astronomy Seminar
6.11 Nigul Olspert (Aalto University): Time series analysis of solar and stellar data. Case study: young solar analogue LQ Hya
13.11 Mika Juvela (University of Helsinki): Dust in the Milky Way
20.11 Brian Mazur (University of Toledo): Star Formation in Orion: Wide, Young Binaries
27.11 Mika Saajasto (University of Helsinki): Studentships at the Nordic Optical Telescope
4.12 Till Sawala (University of Helsinki): The APOSTLE simulations: solutions to the Local Group's cosmic puzzles
8.12 Extraordinary seminar Massimiliano Bonamente: Detection of a possible WHIM filament towards PG 1116+215 with Chandra and HST
11.12 Joonas Uusitalo (University of Helsinki): The AD 775 radiocarbon anomaly - Caused by a solar flare

Past Program Spring 2015

16.1 Olli Wilkman: Lightcurve simulations for non-convex asteroids
23.1 Aleksi Vuorinen: Constraining neutron star matter with QCD
30.1 John Regan: Simulations of the Universe
6.2 Elizabeth Cole: Magnetic Activity of LQ Hya
13.2 Ghassam Gozaliasl: Evolution of the central galaxies in X-ray galaxy groups
20.2 Talvikki Hovatta (Metsähovi Radio Observatory): Magnetic fields in blazar jets
26.2 Extraordinary Seminar Martin Pessah: On the Dynamics of Helium in the Dilute Intracluster Medium
27.2 Ronan Rochford: DYMPHNA3D: An introduction into the world of Pulsars
6.3 Teaching Break
20.3 Jussi Väliviita: Planck satellite and its cosmology results CANCELLED
26.3 Extraordinary Seminar Till Sawala: Local Group Galaxies Emerge from the Dark
27.3 Sebastien Muller: PKS1830-211: the molecular absorption at z=0.89 and the background blazar
3.4 Easter Break
10.4 Jussi Ahoranta: High resolution X-ray analysis of ICM at core regions of NGC 4636 galaxy group
17.4 Erika Palmerio: Fine Structures in Coronal Mass Ejection-driven Sheath Regions
24.4 Natalia Lahén: Equal-mass Galaxy Mergers: Initial Conditions and Subresolution Astrophysics
29.4 Daniel Mege: The Planetary Highland Terrain Hopper: An all-terrain fractionated Solar System explorer
12.6 Extraordinary Seminar Dagmara Oszkiewicz: Traces of differentiation in the Flora region

Past Program Autumn 2014

9.9 Ciro Pinto: Turbulence in clusters of galaxies as revealed by X-ray spectroscopy
12.9 Felicia Ziparo: The role of the environment in the evolution of star formation
17.9 Karel Nel: Drawing the Unimaginable, COSMOS
19.9 Mika Juvela: Star forming clouds in the Milky Way - observations from near-infrared to millimetre wavelengths.
26.9 Thomas Hackman: Stellar spot activity - methods and results
3.10 Jan Snellman: Relaxation-type second-order closure models in astrophysical hydrodynamics
10.10 Clif Kirkpatrick: Hot Outflows in Galaxy Clusters
17.10 Julia Martikainen: Meteorite spectrometry using the University of Helsinki Vis-SWIR spectrometer
31.10 Simon Karl: Accurate dynamics around supermassive black holes with the hybrid tree-code "rVine"
4.11 Petri Väisänen (note Tuesday): SUNBIRD/SALT: Young massive star clusters and superwinds in strongly star-forming galaxies
14.11 Pauli Pihajoki: Simulating the orbital dynamics of multiple black hole systems
21.11 Kimmo Kettula: Weak lensing mass calibration of galaxy groups and low mass clusters in the COSMOS and CFHTLS fields
28.11 Karri Muinonen: Coherent Backscattering by Particulate Media of Nonspherical Particles
5.12 No Seminar: Graduate school event
12.12 Olli Sipilä: H2D+ observations give an age of at least one million years for a cloud core forming Sun-like stars

Past Program Spring 2014

17.1 Anton Baushev: The real and apparent convergence of N-body simulations of the dark matter structures: is the Navarro-Frenk-White profile real?
24.1 John Regan: Danger! Simulating the Collapse of Early Massive Black Holes.
31.1 Anne Virkki: Planetary radar research at the Arecibo Observatory
7.2 Grigori Fedorets: Spin and shape analyses for the slowly rotating asteroid (39420) 2084 T-2
14.2 Mika Juvela: C3PO strikes back - progress report on the project Galactic Cold Cores
21.2 Jyri Lehtinen: Time series observations of active stars
28.2 Mika Saajasto: Probing the properties of interstellar dust with infrared light scattering
7.3 Extraordinary Seminar Alberto Cellino: Physical properties of Asteroids
14.3 Murray Brightman: Compton thick AGN in the distant Universe
21.3 Antti Rantala: Cosmological Zoom-in Initial Conditions and the Formation of Galaxies
28.3 Artem Kupri: Strong lensing as a test of the vacuum energy density in the Lambda-CDM model
4.4 Kimmo Kiiveri: Simulating Planck data - CMB timeline-to-map Monte Carlo simulations and beam window functions
11.4 Johanna Malinen: Interstellar medium and initial stages of star formation: comparing simulations and observations
18.4 Easter break --No seminar
25.4 Jussi Aaltonen: Searching for dark matter in clusters of galaxies
30.4 Bodo Ziegler: The busy life of the cluster complex RXJ1347-11

Past Program Autumn 2013

6.9 Peter Johansson: Modelling supermassive black holes in galaxy simulations
13.9 Jorma Harju: Observations and models of the evolution of prestellar cores
20.9 Kimmo Kettula: Weak lensing calibration of scaling relations in galaxy groups.
27.9 Oskari Miettinen: A MALT90 study of the chemical properties of massive IRDC clumps
4.10 Jörn Warnecke: Bipolar magnetic structures driven by stratified turbulence with a coronal envelope
11.10 Emilia Järvelä: Multifrequency study of radio-loud Narrow-line Seyfert 1 galaxies: A search for spirals launching relativistic jets
18.10 Ghassem Gozaliasl: Evolution of the luminosity gap in X-ray galaxy groups from CFHTLS-XMM field
25.10 Bidya Binay Karak: Role of meridional circulation in modeling the solar cycle using the flux transport dynamo model
1.11 Lauri Jetsu: Did the ancient egyptians record the period of the eclipsing binary Algol - The raging one?
8.11 Emily Freeland: Intergalactic Gas in Groups of Galaxies: Implications for Dwarf Spheroidal Formation and The Missing Baryons Problem
15.11 Anne Lähteenmäki: Multifrequency studies of active galactic nuclei
22.11 Mikael Granvik: Life and death of the Chelyabinsk asteroid
29.11 Karri Muinonen: Gaia - an ultraprecise survey of our Galaxy
6.12 Finnish Independence Day -- No seminar
13.12 Miikka Väisälä: High-resolution ammonia mapping of the very young protostellar core Chamaeleon-MMS1
18.12 Tom Millar: Complex Molecule Formation in Protoplanetary Disks

Past Program Spring 2013

18.1 Petri Käpylä: United approach to investigating stellar magnetic activity
25.1 Francesco Miniati: Generation of Magnetic Field in Cosmic Structure
1.2 Lauri Haikala: The European Extremely Large Telescope (E-ELT)
7.2 Alana Rivera: Searching for Clues in High-Mass Star Formation (Note Thursday)
15.2 Mikael Granvik: Constraints for the formation and evolution of planetary systems with the Large Synoptic Survey Telescope
22.2 Shinsuke Abe: Hayabusa-2; Sample return mission of a C-type asteroid (162173) 1999 JU3
28.2 Patricia Spinelli: Weak lensing analysis of galaxy systems (Note Thursday)
7.3 Masayuki Tanaka: High redshift groups of galaxies (Note Thursday)
8.3 Eva Schinnerer: The relation between ISM and star formation on cloud-scales - New insights from the Whirlpool galaxy
22.3 Olli Sipilä: HD depletion in starless cores
26.3 Toshifumi Futamase: A new approximation for the non-linear DM power spectrum beyond BAO scales (Note Tuesday)
29.3 Easter break --No seminar
5.4 Sébastien Comerón: A deeper look on thick discs using data from the Spitzer Survey of Stellar Structure in Galaxies (S4G)
12.4 Hanna Pentikäinen: Laboratory spectrometry of meteorite samples at visible to near-infrared wavelengths
19.4 Kyösti Ryynänen: Life out of chaos
26.4 Viola Allevato: Halo occupation of X-ray AGN in the COSMOS field
3.5 Shaun Hotchkiss: The (misbehaving) integrated Sachs Wolfe effect from "superstructures"

Past Program: Autumn 2012

7.9 Maarit Mantere: Solar and stellar cycles: observations and MHD modelling
14.9 Heidi Yli-Kankahila: Formation of Early-type Galaxies through mergers of gas-rich disk galaxies
21.9 Elizabeth Cole: Doppler Imaging of LQ Hydrae
28.9 Karri Muinonen: Scattering of electromagnetic waves by Solar System objects: from the first principles to the new asteroid magnitude system
5.10 Olli Wilkman: Asteroid lightcurve phase shift from rough-surface shadowing
12.10 Mika Juvela: Update on the project Galactic Cold Cores
19.10 John Regan: Simulations of the Formation and Evolution of Super Massive Black Holes
26.10 Teaching break -- No seminar
1.11 Alexis Finoguenov: COnstrain Dark Energy with X-ray (CODEX) clusters. Colloqium talk, note the unsual time.
9.11 Minja Mäkelä: Structure and star formation in cometary globules: NIR observations of CG1 and CG2
16.11 Jorma Harju: Observational tests for the chemistry and dynamical evolution of prestellar cores
23.11 Tuomas Lunttila: Radiative transfer modelling of interstellar clouds
30.11 Andi Hektor: Dark side of the Universe: enlightenment through gamma-rays
7.12 Thursday (6.12) is Finnish Independence Day -- No seminar
14.12 Ghassem Gozaliasl: Understanding the evolution of structure in the Universe with help of galaxy groups

Past Program: Spring 2012

16.1 Karri Muinonen: Asteroid orbital inversion using a virtual-observation Markov-chain Monte Carlo method
20.1 Maarit Mantere: "Alternative interpretation of starspots"
23.1 Hannakaisa Lindqvist: Stereophotogrammetry: a new way of modeling light scattering by mineral dust
27.1 Mika Juvela: "Herschel observations of cold interstellar clouds detected by Planck"
30.1 Mikael Granvik: Building near-Earth-object population models with data from CSS and NEOSSat
3.2 Julien Montillaud: "Between molecules and solid state: Interstellar PAHs and Very Small Grains"
6.2 Tomas Kohout: Magnetic susceptibility meter for asteroid regolith composition studies
10.2 Matts Roos: "Some recent astrophysics issues"
13.2 Victor Solea: An MC-MC approach to periodicity determination of variable stars
17.2 Thomas Hackman: "Stellar spot activity - some recent results"
24.2 Roberto De Propris: "Galaxy Mergers"
27.2 Lauri Pesonen: Meteorite Impact Cratering - Geophysical Aspects
2.3 Oskari Miettinen: "Infrared dark clouds - A case study of the filamentary IRDC G304.74+01.32"
5.3 Dagmara Oszkiewicz: Diﬀerentiated asteroid families - the missing link to the history of our Solar System
9.3 Teaching break -- No seminar
12.3 Jani Tyynelä: Applicability of the Rayleigh-Gans approximation for snowflakes at microwave frequencies
16.3 Jan Snellman: Some new results on hydrodynamical closure models
19.3 Anne Virkki: Circular polarization ratio for aggregates of spherical particles
23.3 Olli Sipilä: Chemical and physical modeling of prestellar cores
29.3. Mark Rawlings: "The current status of ALMA" (13:15 in D116)
30.3 Tuomas Lunttila: "Dust radiative transfer using hierarchical grids"
6.4 Easter break: No seminar
13.4 Paula Kyyrö: "The density profile and fragmentation of Taurus Molecular Cloud-1"
16.4 Evgenij Zubko: Light scattering by cometary dust: Large-particle contribution
20.4 Anna Parikka: "The physical and chemical state of cold dust cores mapped with Herschel"
23.4 Maria Gritsevich: How to catch a shooting star: Fireballs producing meteorites
27.4 Victor Solea: "Long-term photometric analysis of a chromospherically active variable star"
4.5 Hannu Kurki-Suonio: "Euclid - the next cosmology mission"
30.5. Douglas Whittet: "Methanol in interstellar ices"
30.5 Emily Hardegree-Ullman: "Chemical and Physical Conditions of the core SL42 in the Corona Australis Molecular Cloud"
1.6. Thorsten Naab: "Modelling the Antennae Galaxies"