Observatory
University of Helsinki Annual Report 2009
Observatory P.O. Box 14, FI-00014 University of Helsinki, Finland
http://www.astro.helsinki.fi/
Foreword
There is no need to repeat the contents of my foreword in the previous annual report dated June 6th, 2009. From a profes- sional point of view, I find nothing good towriteabout the rest this year. The following lines
Anger may in time change to gladness;
vexation may be succeeded by content.
But a kingdom that has once been destroyed can never come again into being;
nor can the dead ever be brought back to life.
There is a wisdom which tells:
When to go and when to return.
What is to be done and what is to be left undone.
What is fear and what is courage.
What is bondage and what is liberation.
This is pure wisdom.
are quotations from two completely different kinds of books.
Now it is a good time toreadthose books again.
Lauri Jetsu
Director of the Observatory Helsinki, December 22nd, 2009
Contents
1 Interstellar medium, star formation and magnetic activity of stars 3
1.1 Research activities . . . 3
1.2 Progress and highlights of scientific results in 2009 . . . 3
1.2.1 Magnetic activity in stars and circumstellar discs . . . 3
1.2.2 Interstellar clouds . . . 4
1.2.3 Prestellar cores and star formation . . . 6
1.2.4 The Planck and Herschel satellite projects . . . 6
1.2.5 Extragalactic Background Light . . . 8
1.3 External financing and resources . . . 9
1.4 Tests of learning . . . 9
1.5 Visits abroad . . . 10
1.6 Papers read at scientific conferences, symposia, meetings etc. . . 11
1.7 Visiting academics . . . 11
1.8 Membership in scientific and scholarly societies . . . 12
1.9 Other activities . . . 12
1.10 Refereeing and Other Publishing Activities . . . 12
2 High Energy Astrophysics 13 2.1 General approach . . . 13
2.2 Science topics . . . 13
2.2.1 The solar corona . . . 13
2.2.2 Clusters of galaxies . . . 14
2.3 Development of data analysis software . . . 14
2.4 External financing and resources . . . 15
2.5 Tests of learning . . . 15
2.6 Visits abroad . . . 15
2.7 Membership in scientific and scholarly societies . . . 15
3 Planetary System Research 19 3.1 Research activities . . . 19
3.2 External financing and resources . . . 21
3.3 Tests of learning . . . 21
3.4 Visits abroad . . . 21
3.5 Papers read at scientific conferences, symposia, meetings etc. . . 22
3.6 Visiting academics . . . 23
3.7 Membership in scientific and scholarly societies . . . 23
3.8 Refereeing and Other Publishing Activities . . . 23
4 Lectures in 2009 25 5 Library 26 5.1 Library Merger . . . 26
5.2 LISA VI Conference . . . 26
5.3 Membership in scientific and scholarly societies . . . 26
6 Observatory Board 2007–2009 27 7 Publications 28 7.1 Articles in refereed journals (B1) . . . 28
7.2 Papers in conference publications and compilations (B2) . . . 30
8 Academic degrees 1995–2009 31
1 Interstellar medium, star formation and magnetic activity of stars
Staffwith a Ph.D. Thomas Hackman, Ph.D.
Lauri Haikala, Docent Jorma Harju, Docent Mika Juvela, Docent Maarit Korpi, Docent Petri K¨apyl¨a, Ph.D.
Kimmo Lehtinen, Docent Kalevi Mattila, Prof.
Ilkka Tuominen, Prof.emer.
Nathalie Ysard, Ph.D.
Ph.D. students Anne Liljestr¨om, M.Sc Marjaana Lindborg, M. Sc Tuomas Lunttila, M.Sc.
Johanna Malinen, M.Sc.
Minja M¨akel¨a, M.Sc.
Oskari Miettinen, M.Sc.
Marianna Ridderstad, M.Sc.
Ky¨osti Ryyn¨anen, M.Sc.
Olli Sipil¨a, M.Sc.
Jan Snellman, M.Sc.
Associated scientists Axel Brandenburg, Ph.D., Prof.
(Nordita, Stockholm, Sweden), Thorsten Carroll, Ph.D.
(Astroph. Inst. Potsdam, Germany) Stephan Hotzel, Ph.D.
(Cologne, Germany) Ilya Ilyin, Ph.D.
(Astroph. Inst. Potsdam, Germany), Peter Johansson, Ph.D.
(University Observatory, Munich) Oleg Kochukhov, Ph. D.
Uppsala University, Sweden), Heidi Korhonen, Ph.D.
(ESO, Garching, Germany) Veli-Matti Pelkonen, PhD.
(IPAC, Pasadena) Jaan Pelt, Ph.D.
(Tartu Observatory, Estonia) Peter Petrov, Ph.D.
(Crimean Astroph. Obs., Ukraine), Nikolai Piskunov, Ph.D., Prof.
(Uppsala University, Sweden), Mark Rawlings, Ph.D.
(Joint ALMA office, Santiago, Chile) Petri V¨ais¨anen, Ph.D.
(SALT, South Africa) Nadezhda Zolotova, Ph.D.
Saint-Petersburg State Univ., Russia
1.1 Research activities
The activities of the research group are directed to the fol- lowing fields: (1) the formation of protostars in dense molec- ular cloud cores; (2) the properties and evolution of dust and molecular gas in interstellar clouds; (3) radiative transfer and magnetohydrodynamic (MHD) modelling of interstellar clouds and protostellar accretion discs; (4) MHD-modelling of solar and active late-type star convection and turbulent dynamos and related optical spectropolarimetric observations using in- version methods; (5) the optical and infrared extragalactic background radiation.
The group uses ground-based and space-borne optical/ infrared, (sub)millimetre, and radio telescopes. The stud- ies often are conducted in collaboration with research groups from other countries. In recent years the ESO facilities have been of growing importance. The group has successfully performed several ESO/VLT observing programs and spe-
cial attention is paid to the 12-m Atacama Pathfinder Ex- periment (APEX) and to the Atacama Large Millimetre Ar- ray (ALMA). APEX became publicly available in 2006 and ALMA will start its operation in 2010. The group has been well informed about available ESO telescopes and facilities:
Mattila has been Finland’s representative in the ESO Council since 2004. Haikala has been (after Tuominen) Finland’s rep- resentative in the Scientific Technical Committee since 2007.
Harju was since 2004 a member of the ALMA European Sci- entific Advisory Committee and, from the beginning of Febru- ary 2009, Haikala has acted as the Finnish representative. Ju- vela has served as a member and Harju as an Expert Advisor in the ESO Observing Programmes Committee.
During the past several years ESA’s Infrared Space Ob- servatory (ISO) has been important for the group. The ex- ploitation of the ISO data has continued intensively, often in combination with near-IR and (sub)mm data from ESO and other ground based telescopes such as the Australian Tele- scope Compact Array, the Effelsberg 100-m and the Onsala 20-m radiotelescopes, and the 2.5-m Nordic Optical Tele- scope.
Based on its ISO experience, the group has been par- ticipating in the relevant Planck Surveyor science projects.
Among the other future ESA missions the group is particu- larly well-prepared to make use of the Herschel Space Obser- vatory mission and is already coordinating one Herschel open time key programme. Our plans also include expanding and emphasizing our theoretical research of star formation and in- terstellar cloud physics.
Spectropolarimetric observations of active late-type stars using the high resolution Echelle spectrograph SOFIN at the Nordic Optical Telescope, La Palma, Spain, have continued successfully. The time series of spectroscopic observations for surface temperature maps already extend over 18 years.
Simultaneous local and global MHD modelling and model development has been actively carried out, applications rang- ing from the solar dynamo activity to the active rapid rotators followed up by the observational programme, also including MHD turbulence in accretion disks around pre- or protostel- lar cores, and molecular clouds and star-forming regions in galaxies.
1.2 Progress and highlights of scientific results in 2009
(for references see the list of publications)
1.2.1 Magnetic activity in stars and circumstellar discs We have successfully continued the investigation of the mag- netic field structure, especially the polarity of the field in spots of two active longitudes, in active late-type stars (detected earlier on by the group using surface temperature maps and named as ”active star Hale rule”). Spectroscopic observa-
tions, based on which surface temperature maps have been inverted, were started in 1991 with the high resolution spec- trograph SOFIN at the Nordic Optical Telescope, La Palma.
The time series collected since is one of the few most exten- sive and complete existing data sets to study long-term vari- ability (cycles) in active late-type stars. An important devel- opment is the magnetic inversions based on new spectropo- larimetic data with upgraded spectropolarimeter and reduc- tion software, giving the first observational proof for the the- oretical prediction of the magnetic field polarity. The work is done in collaboration with astronomers in Uppsala, Sweden, and Potsdam, Germany, most of the collaborators originally having worked in Helsinki Observatory and/or Oulu Univer- sity. We have also continued the research on the behaviour of solar activity using sunspot data over 400 years, from the Maunder minimum to the present one. This is also gener- ally important because the solar activity has now been in very long minimum and solar irradiance to Earth’s atmospere has decreased.
Simultaneously to the observations, local and global MHD models (PENCIL-CODE, MEFISTO;Korpi,K¨apyl¨a,Lilje- str¨om, Lindborg, Snellman) have been developed and uti- lized, to be able to investigate the transformation from solar- like dynamo activity to the activity seen in the active rapid ro- tators. Numerical modeling has yielded new results in a vari- ety of systems: local turbulence models have been utilized to study the turbulent transport of angular momentum (Snellman et al. 2009, Korpi et al. 2009 in press), and numerical studies of convection have, for the first time, revealed a large-scale dynamo (K¨apyl¨a et al. 2009a,b,c). The latter project was ac- cepted to the DEISA-DECI programme (CONVDYN PId by Korpi), from which 900 000 CPU hours of computing time was granted and used during the year 2009. An international conference on the topic of Astrophysical Magnetohydrody- namics was organised by the MHD-group in Kiljava, Nurmi- jarvi, Finland, during 6.–10. of April 2009, with roughly 50 participants from 13 different countries.
1.2.2 Interstellar clouds
Molecular line and NIR study of cometary clouds.Cometary shape is common in the interstellar space. The objects range from tiny globulettes embedded in HII regions to parsec sized cometary globules and to cometary shaped star forming re- gions like Corona Australis. We are using molecular line ob- servations and NIR imaging to study the properties of these sources (size, mass, density, dynamics, star formation) to gain insight to their formation mechanism.
Even though Cometary globule 12 (CG 12) has been clas- sified as a cometary globule it is in fact a medium- and low mass star forming region 210 pc above the Galactic plane.
To complement our earlier molecular line studies (Haikala et.
al 2006 and Haikala and Olberg 2007) NIR J, H, and Ks imaging obtained with SOFI at the La Silla NTT telescope
was used to analyse the stellar content and the structure of CG 12. A color coded SOFI image of CG 12 is shown in 1.
Several new members and member candidates of the CG 12 stellar cluster were found. The new members include in par- ticular a highly embedded source with a circumstellar disk or shell. The central source of the known collimated molecu- lar outflow in CG 12 and an associated “hourglass”-shaped object due to reflected light from the source were also de- tected. HIRES-enhanced IRAS images were used together with SOFIJHKs imaging to study the two associated IRAS point sources. Two new 12µm sources coinciding with NIR excess stars were detected in the direction of IRAS 13546–
3941. The IRAS 13547–3944 emission at 12 and 25µm orig- inates in the Herbig AeBe star h4636n and the 60 and 100µm emission from an adjacent cold source. The study will appear in A&A (Haikala and Reipurth 2009, in press).
Cometary Globule 1 is the archetype cometary globule in the Gum nebula. NTT SOFI NIR Js, H, and Ks imag- ing and stellar photometry is used to analyse the structure of CG 1 and the extinction of stars in its direction (Haikala and M¨akel¨a). Preliminary results include an embedded, pre- viously unknown protostar in the globule head. The observed maximum extinction in the cloud is∼10 magnitudes in vi- sual. Like in the case of CG 12 HIRES enhanced IRAS im- ages were used together with SOFIJHKs imaging to study the associated IRAS point source, 07178-4430. This point source resolves into two separate sources. The 12 and 25µm emis- sion comes from the Herbig AeBe star NX Puppis and the 60 and 100µm emission from the adjacent, newly detected protostar.
Scattered Hαfrom interstellar clouds. Lehtinen, Ju- vela & Mattila have identified an undocumented large translu- cent cloud, detected by means of its enhanced radiation on the SHASSA (Southern H-Alpha Sky Survey Atlas) survey.
They compared the observed Hα surface brightness of the cloud with predictions of a radiative transfer model, by us- ing the WHAM (Wisconsin H-Alpha Mapper) survey as a source for the Galacticα interstellar radiation field illumi- nating the cloud. Visual extinction through the cloud is de- rived from 2MASSJ,HandKband photometry. Far-infrared ISOSS (ISO Serendipitous Survey), IRAS and DIRBE data was used to study the thermal emission of dust, and LAB (The Leiden/Argentine/Bonn Galactic HI Survey) was used to study 21 cm HI emission associated with the cloud. Radia- tive transfer calculations of the Galactic diffuse Hαradiation indicated that the surface brightness of the cloud can be ex- plained solely by radiation scattered offdust particles in the cloud. The maximum visual extinction through the cloud is about 1.4 mag. The cloud is found to be associated with 21 cm HI emission at a velocity∼ −9 km s−1. The total molecular mass of the cloud is about 310–460 solar masses. There was no sign of star formation in this cloud. The distance of the cloud is from the Hipparcos data estimated to be∼ 75 pc, making it one of the closest translucent molecular clouds.
Figure 1: Colour coded SOFI image of CG 12. TheJ,H, andKs bands are coded in blue, green and red, respectively. Square root scaling has been used to better bring out the faint surface brightness structures.
Magnetic fields in interstellar clouds.Studies were com- pleted of the polarized sub-millimeter emission from dust grains in interstellar clouds. In a magnetic field, dust grains remain aligned as long as their rotation speed is significantly larger than their thermal rotation speed. The grains are believed to be spinned up mainly by radiative torques. The efficiency of radiative torques was investigated using magnetohydrody- namic cloud simulations and detailed radiative transfer mod- elling (Pelkonen et al. 2009). Results indicate large spatial variations in the polarization efficiency. In particular, in dense clouds, the dust emission is not likely to probe magnetic fields deeper than a few magnitudes inAV.
Through Zeeman effect, magnetic fields cause splitting of some radio lines. Because the split components have opposite circular polarization, the line-of-sight component of the mag- netic field can be estimated from the Stokes I and V spectra.
With radiative transfer modelling, three-dimensional magne- tohydrodynamic simulations could be compared with existing measurements of the Zeeman effect in cloud cores (Lunttila et al. 2009). Good agreement was found between models of super-Alfv´enic turbulence, combined with self-gravity, and available observations of OH molecule lines. This suggests that the average magnetic field of molecular clouds may be low and supports the idea of turbulence as a central factor behind the formation of self-gravitating cloud cores.
1.2.3 Prestellar cores and star formation
Infrared dark clouds as precursors to high-mass stars and star clusters. The so-called infrared dark clouds (IRDCs), which are identified as extinction features against the bright mid-infrared (MIR) Galactic background radiation, are likely to represent very early stages of high-mass star/star cluster formation. In particular, some of the IRDCs may harbour high-mass starless cores (HMSCs), which provide the best targets to study the initial conditions of high-mass star forma- tion. We have mapped the IRDC G304.75+01.32 in the 870 µm dust continuum emission with the LABOCA bolometer on APEX. The obtained LABOCA map is presented in Fig. 2 (Miettinen & Harju 2009, submitted). Twelve clumps were identified from the 870µm map. Star formation has already started in the cloud as four of the clumps are associated with infrared (MSX and/or IRAS) point sources. The remaining eight clumps are MIR dark. The masses of these MIR dark clumps,∼40−200 M¯, are sufficiently large to enable high- mass star formation. Thus, some of them could be candidates of being/harbouring HMSCs. The submillimetre map of the cloud also enabled us to study the clump mass and spatial distributions. The clump masses in G304.74 were compared with the clump mass spectra from more extensive surveys of IRDCs. It was found that the clump mass distributions in G304.74 and in several other IRDCs probably represent the subsamples of the same parent distribution. Also clump sep- arations in different IRDCs are comparable to each other, and
also to the corresponding random distributions. This suggests that the fragmentation length-scale does not vary much from cloud to cloud. The results of this study support the scenario that the origin of IRDCs, and their further fragmentation into smaller subunits is caused by supersonic turbulence in accor- dance with results from giant molecular clouds.
Chemical modelling of prestellar cores. Taking advan- tage of recently published chemical rate coefficients for the H+3 +H2reacting system (Hugo et al. 2009, J. Chem. Phys., 130, 164302), we have developed chemical models to calcu- late chemical abundances in prestellar cores. Chemical evo- lution in the cores affects, among other things, the observ- able emission radiation from these objects, and thus chemical models can be used to constrain the properties of the cores by comparing model predictions with observations.
One such comparison is presented in Fig. 3. In the Fig- ure, an observation by Harju et al. (2008) of line emission produced in the H2D+ 110 - 111 transition is plotted against the model prediction of Sipil¨a et al. (2009, in press). The agreement between the observation and the model prediction is good, even though the chemical model in this case includes only the lightest elements. This result is consistent with the depletion of heavy substances toward the centers of prestellar cores, as has been widely discussed in the literature.
1.2.4 The Planck and Herschel satellite projects
The Planck and Herschel satellites were launched success- fully in May 2009. By the end of 2009, the first data were received from both satellites.
We participate in several science projects within the Planck Surveyor satellite consortium. The main emphasis is on stud- ies of dense interstellar clouds and especially their cold and compact cloud cores. The population of cold cores (Tdust <
12 K) is still poorly known. Planck is the first space borne mission that has the sensitivity and the resolution necessary for the study of the cold core population over the whole sky.
At the end of 2009, Planck has already scanned a significant fraction of the whole sky and the preliminary analysis of the observations has resulted in the detection of hundreds of new cold cores.
We are coordinating a Herschel Open Time Key Programme, where a sample of the Planck-detected cores are investigated in more detail using the Herschel PACS and SPIRE instru- ments. Herschel can observe wavelengths close to the peak of dust emission,λ ∼ 100−500µm. Compared to Planck, Herschel has much higher spatial resolution. This makes it possible to study the internal structure of the selected cores and to determine their evolutionary stages and their relation to future star formation. The key programme was awarded
∼151 hours of observing time on the Herschel satellite. The main observations are expected to start at the end of 2010.
However, a few cores were already mapped as part of the Herschel Science Demonstration Phase and the initial results
Figure 2: LABOCA map of the 870µm dust continuum emission from the IRDC G304.74. The green and black plus signs mark the positions of the IRAS and MSX point sources, respectively.
Figure 3: Model predictions for the line emission produced in the ground-state transitions of ortho-H2D+(372 GHz, top) and para-D2H+ (692 GHz, bottom) from the prestellar core Oph D as observed with APEX (Sipil¨a et al. 2009, in press).
The H2D+line is plotted against the observed profile (dotted curve, Harju et al. 2008). Both transitions are potential tools of prestellar core studies with ALMA.
were presented in a workshop in December 2009.
We participate in several other Planck science projects, including the study of nearby galaxies. We are also involved in the Herschel key programme HiGal that is going to map a large fraction of the plane of our Galaxy.
1.2.5 Extragalactic Background Light
Search for the optical Extragalactic Background Light.
Using our understanding of the light scattering in dense in- terstellar clouds of dust, we have been developing a method for the detection of the optical extragalactic background light.
This is the so-called “shadow of a dark cloud method”. Based on our previous photometric EBL observing program we have developed a spectroscopic analogy for it. This new tech- nique utilizes the difference between the spectra of the dif- fuse galactic scattered light (absorption line spectrum) and the EBL (pure continuum spectrum with possible discontinu- ities). For the spectroscopic observing program we (Mattila, Lehtinen, V¨ais¨anen) earlier received 20 hours observing time at ESO VLT telescope and FORS instrument. For the ESO Period 82, 18.5 hours were again allocated but only a few hours were realised in 2008/09.
The modelling of the FORS spectra requires knowledge of the spectrum of the Local Interstellar Radiation Field (ISRF).
A new population synthetic spectral model is being devel- oped along the lines of an earlier model by Mattila based on the high-resolution stellar spectrum library STELIB (Borgne et al. 2003, A&A 4002, 433) and on stellar distribution pa- rameters derived from HIPPARCOS and other recent data by Flynn et al. (MNRAS 372, 1149, 2006). An excellent fit is found between the ISRF spectrum thus derived and the observed scattered light spectrum of the dark nebula Lynds 1642, our target for the VLT FORS spectroscopy.
Far-infrared Extragalactic Background Light. Using data from the ISOPHOT instrument of the ISO satellite, we have completed a study of the extragalactic far-infrared back- ground light at 90, 150 and 180µm (Juvela, Mattila et al.
2009, the ISOPHOT EBL project). The signal represents a significant fraction of the cosmic energy output from stars that has been reprocessed by interstellar dust and is redshifted to far-infrared wavelengths. Our study is the first independent measurement of the absolute surface brightness of the cos- mic infrared background radiation (CIRB) obtained since the COBE result some ten years earlier. Our values are in agree- ment with the published COBE results, confirming the inten- sity of this extragalactic component at a level of∼1 MJy sr−1 at wavelengths∼150–180µm.
Identification of far-infrared sources at the North Galac- tic Pole.As a follow-up of the far-infrared extragalactic back- ground light (ISOPHOT EBL) project V¨ais¨anen (SALT, South Africa), Juvela, Mattila et al.(2009) have performed observa- tions of the far-infrared (FIR) sources detected as part of that project. We have observed the fields at the North Galactic
Pole region in the optical and near-IR, and complement these data with Sloan Digital Sky Survey SDSS photometry, and spectroscopy where available, and present identifications of the 25 FIR sources which reach down to 150 mJy in all three ISOPHOT bands at 90, 150 and 180µm. Identifications are done by means of full spectral energy density fitting to all sources in the FIR error circle areas. Approximately 80 per cent are identified as star-forming or star-bursting galaxies at redshifts z<0.3. We also found that more than half of the counterparts have disturbed morphologies, and some 40 per cent are blends of two or more nearby star-forming galaxies.
The blended sources have an effect on the FIR source counts.
In particular, taking into account realistic confusion or blend- ing of sources, the differential FIR counts move down by a factor of 1.5 and steepen in the 100 to 400 mJy range.
1.3 External financing and resources
2009: Person-months of work: 184 Academy of Finland: 440 000e Ministry of Education: 100 000e Foundations: 28 500e
1.4 Tests of learning
Pelkonen, Veli-Matti
Ph.D. thesis: Two views on interstellar dust: near- infrared scattering and polarized thermal dust emis- sion; 2009, University of Helsinki, Department of As- tronomy
Kainulainen, Jouni
Ph.D. thesis: Studies of the star-forming struc- tures in the dense interstellar medium: a view by dust extinction; 2009, University of Helsinki, Department of Astronomy
Lehtinen, Jyri
M.Sc. thesis: Continuous period search method and its application to stellar photometry; 2009, Univer- sity of Helsinki, Department of Astronomy
Suutarinen, Aleksi
M.Sc. thesis: CH- ja OH-molekyylien pylv¨astiheyksien v¨alinen korrelaatio t¨ahtienv¨alisess¨a molekyylipilvess¨a TMC-1; 2009, University of Helsinki, Department of Astronomy
1.5 Visits abroad
Hackman, Thomas
NORDITA workshop “Solar and stellar dynamos and cycles”, Stockholm, Sweden, 5.–7.10.2009, 3 days NOT OPC Meeting 4.-5.6.2009, Lund, Sweden, 3.–6.6.2009, 4 days
NOT OPC Meeting, La Palma, Spain, 4.–
8.12.2009, 5 days Haikala, Lauri
ESO STC Meeting, Garching, Germany, 21.–
23.4.2009, 3 days
ESO ESAC Meeting, Garching, Germany, 15.6.2009, 1 day
University of Stockholm,Stockholm. Sweden 23.–24.11.2009, 2 days
Harju, Jorma
European ALMA Science Advisory Committee, ESO, Garching, Germany, 8.–10.1.2009; 3 days
Observations with the Effelsberg 100-m telescope, Germany, 23.–26.11.2009, 4 days
I. Physikalisches Institut, Universit¨at zu K¨oln, 27.11.2009, 1 day
Juvela, Mika
AKARI Meeting, University of Tokyo, Japan, 14.–23.2.2009, 10 days
Planck Satellite working group meeting, Toulouse, France, 31.3.–5.4.2009, 6 days
ASTROSIM project Steering Committee meeting, Paris, 11.–12.9.2009; 2 days
Planck Core Team and Consortium Meetings, Bologna, Italy, 1.–7.11.2009; 7 days
IPAC, Pasadena, USA, 12.–19.11.2009; 8 days Herschel workshop meeting, Madrid, Spain, 13.–
19.12.2009, 7 days Kainulainen, Jouni
Max Planck Institut f¨ur Astronomi, Heidelberg, Germany, 13.–16.1.2009, 4 days
Korpi, Maarit
PI of the NORDITA-programme ’Solar and stel- lar dynamos and cycles’, Stockholm, Sweden, 27.9–
17.10.2009, 20 days
’MHD days’ AIP, Potsdam, Germany, 7.–
11.12.2009, 5 days
K¨apyl¨a, Petri
5.–12.2.2009 NORDITA, Stockholm, Sweden 24.–30.5.2009 NORDITA, Stockholm, Sweden 18.–22.8.2009 NORDITA, Stockholm, Sweden 30.8.–5.9.2009 ‘Natural Dynamos’, Stara Lesna, Slovakia
27.9.–25.10.2009 ‘Solar and stellar dynamos and cycles’, NORDITA, Stockholm, Sweden
7.–11.12.2009 ‘MHD-Days’, AIP, Potsdam, Ger- many
Liljestr¨om, Anne
CASA workshop, ESO Headquarters, Garching, Germany, 10.–13.5.2009, 4 days
Lindborg, Marjaana
IAU General Assembly, Rio de Janeiro, Brazil, 3.–14.8.2009, 11 days
NORDITA, Stockholm, Sweden, 5.–9.10.2009, 5 days
SEAC 2009, Alexandria, Egypt, 28.-31.10.2009, 4 days
Lunttila, Tuomas
Radiative Transfer workshop, Gent, Belgium, 18.–22.8.2009, 5 days
Malinen, Johanna
AKARI Meeting, University of Tokyo, Japan, 14.–23.2.2009, 10 days
Herschel workshop, Madrid, Spain and Planck meeting, Toulouse, France, 25.3.–5.4.2009, 12 days
Herschel data processing and Initial results, Madrid, Spain, 13.–19.12.2009, 7 days
Mattila, Kalevi
ESO Committee of Council, Garching, Germany, 2.–3.3.2008
ESO Council, Vienna, Austria, 3.–4.6.2008 ESO Council, Garching, Germany, 9.–10.12.2008 Miettinen, Oskari
CASA Workshop, ESO Headquarters, Garching, Germany, 10.–13.5.2009, 4 days
Observations with the Effelsberg 100-m telescope, Germany, 23.–26.11.2009, 4 days
M¨akel¨a, Minja
University of Stockholm, Sweden, 23.–
24.11.2009, 2 days
Pelkonen, Veli–Matti
Planck WG7 Meeting, Toulouse, France, and Her- schel Workshop, Madrid, Spain, 1.–3.4.2009 and 25.3.- .5.4.2009, 12 days
Snellman, Jan
NORDITA, Stockholm, Sweden, 27.9.–
3.10.2009, 7 days Tuominen, Ilkka
IAU General Assembly, Rio de Janeiro, Brazil, 3.–14.8.2009, National representative of Finland, 11 days
NORDITA, Stockholm, Sweden, 4.–13.10.2009, 10 days
Nathalie Ysard
Planck consortium meeting, Bologna, Italy, 3.–
7.11.2009, 5 days
1.6 Papers read at scientific conferences, sym- posia, meetings etc.
Hackman, Thomas
”Detecting differential rotation from spectro- metric and photometric observations”, NORDITA- programme Solar and stellar dynamos and cycles, Stockholm, Sweden, 27.9.–23.10.2009
Korpi, Maarit
”Mean-field dynamo models of rapidly rotat- ing stars”, NORDITA-programme Solar and stel- lar dynamos and cycles, Stockholm, Sweden, 27.9–
23.10.2009
”Dynamos and magnetic field detachement in thermally unstable interstellar flows”, Astrophysical Magnetohydrodynamics, Kiljava, Finland
K¨apyl¨a, Petri
“Large-scale dynamos in local models of con- vection”, Astrophysical Magnetohydrodynamics’, 6.–
10.4.2009 Kiljavanranta, Nurmij¨arvi, Finland
“Bridging the gap between local and global convection simulations”, Natural Dynamos, 30.8.–
5.9.2009, Stara Lesna, Slovakia
“Convection-driven dynamos in spherical wedge geometry”, Solar and stellar dynamos and cycles, 27.9.–25.10.2009, NORDITA, Stockholm, Sweden
“Convection-driven dynamos in spherical wedge geometry”, MHD-Days, 8.–9.12.2009, AIP, Potsdam, Germany
Liljestr¨om, Anne
”Predicting turbulent stresses in a local disk model”, Astrophysical Magnetohydrodynamics, Kil- java, Finland
Lindborg, Marjaana
”Surface temperature maps for II Peg during 1999–2002”, Lindborg, M., Korpi, M.J., Tuominen, I., Ilyin, I., Piskunov, N., IAU General Assembly, Sympo- sium 264, 3-7/8 Solar and stellar variability-Impact on Earth and Planets, Rio de Janeiro, Brazil, poster
”Stellar magnetic fields: observations and nonlin- ear modelling” Astrophysical Magnetohydrodynamics, Kiljava, Finland
”J¨atinkirkkojen aurinkosuuntauksia”, Pentti Koivusen juhlaseminaari, Oulu University, Oulu, Finland, 2.10.2009
Tuominen, Ilkka
”Self-consistent magnetic Doppler imaging of ac- tive stars”, Kochukhov O., Piskunov N., Ilyin I., Tuominen I. IAU General Assembly, Symposium 264, 3-7/8 Solar and stellar variability-Impact on Earth and Planets, Rio de Janeiro, Brazil, poster
”Some notes on sunspot statistics”, NORDITA- programme Solar and stellar dynamos and cycles, Stockholm, Sweden, 27.9–23.10.2009
1.7 Visiting academics
Haikala, Lauri
Shimariji, Yoshito, PhD, National Radio Observa- tory, Japan, 31.8.–6.9.2009
Harju, Jorma
Dr. Stephan Hotzel, GRS mbH, K¨oln, 15.–30.8.
Korpi, Maarit
Prof. Anvar Shukurov, University of Newcastle, 10.–19.4.2009, 9 days
K¨apyl¨a, Petri
Dhrubaditya Mitra, PhD, Queen Mary College, University of London, UK, 20.–22.7.2009
Mattila, Kalevi
Professor Adolf Witt, Ritter Astrophysical Re- search Center, University of Toledo, USA, 23.–
29.5.2009
Professor Douglas Whittet, Department of Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, NY, USA, 27.9.–6.10.2009
Dr. Martin Haas, Astronomische Institut, Univer- sit¨at Bonn, Germany, 24.–28.8.2009
Dr. Karl D. Gordon, Space Telescope Science In- stitute, Baltimore, USA, 22.–25.2.2009
V¨ais¨anen, Petri, PhD, South African Astronomi- cal Observatory, 30.11.–4.12.2009
Tuominen, Ilkka
Jaan Pelt, PhD, Tartu Observatory, Estonia, 14.–
19.6.2009
Nadezhda Zolotova, PhD, St. Petersburg State University, Russia 7.–10.12.2009
1.8 Membership in scientific and scholarly so- cieties
Haikala, Lauri
ESO Scientific Technical Committee, European ALMA Scientific Advisory Committee, February 2009–
Harju, Jorma
European ALMA Scientific Advisory Committee, until February 2009
Mattila, Kalevi
Odin Science Team, 1991–
ISO/ISOPHOT Consortium, 1991–
Planck LFI, 1998–
Finnish National Committee for Astronomy (IAU), Finland, chair
European Southern Observatory, Council
Tuorla Observatory of University of Turku, advi- sory board, Chair
Council of the European Southern Observatory:
Delegate of Finland
International Astronomical Union, Commission 21: SOC member
Tuominen, Ilkka
Finnish National Committee for Astronomy (IAU), representative for Finnish Academy of Science and Letters
Deutsche Forschunggemeinschaft, expert
National Committee for Astronomy for Finland:
Chairman
1.9 Other activities
Mattila, Kalevi
Faculty of Science, University of Helsinki, Fac- ulty Board Member
1.10 Refereeing and Other Publishing Activi- ties
Korpi, Maarit
Astronomische Nachricten, Germany, referee Astronomische Nachricten, Germany, guest editor K¨apyl¨a, Petri
Astrophysical Journal, referee Astronomy & Astrophysics, referee Mattila, Kalevi
Astronomy and Astrophysics, France, referee Astrophysical Journal, USA, referee
Monthly Notices of the R.A.S., U.K., referee Tuominen, Ilkka
Astronomy and Astrophysics, member of board of directors
2 High Energy Astrophysics
Project number 91525005
Research agreements Academy of Finland Tekes
ESA, ESO
Type of research Basic research, share: 50 % Development work, share: 50 % Director of research DocentHuovelin, Juhani
Telephone 19122948
Fax 19122952
E-mail Juhani.Huovelin@Helsinki.Fi
Senior (Ph.D. or higher) Juhani Huovelin, Docent Jukka Nevalainen, docent Linnea Hjalmarsdotter, Ph.D.
Seppo Korpela, D.Sc. (Tech.) Ph.D. student(s) Lauri Alha, Ph.Lic.
Karri Koljonen, M.Sc.
Tuomas Lehto, M.Sc.
Sami Maisala, M.Sc.
Tero Oittinen, M.Sc.
Otto Solin, M.Sc.(Tech.) Auni Somero, M.Sc.
Tuure Takala, M.Sc.
Mikko V¨a¨an¨anen. M.Sc.
Students Jussi Ahoranta
Eero Esko Jasmin Haikonen Associated scientists Pasi Hakala, docent (Turku)
Diana Hannikainen, Docent (Helsinki Univ. of Technology) Rami Vainio, Ph.D.
2.1 General approach
The activities of high energy astrophysics research of HESA (High Energy Space Astronomy) are divided into three areas, (1) fundamental science, (2) development of new instruments for space research, and (3) development of data analysis soft- ware. The first part consists of scientific return (guaranteed time) from the instrument projects (INTEGRAL, SMART-1, Chandrayaan-1), complemented by data from other satellites (e.g. XMM-Newton, HST, RXTE, Chandra, Suzaku). The second part is a continuation to the ongoing hardware projects including research also in detector physics. The science top- ics addressed include coronae and flaring in active stars and the Sun, and studies of clusters of galaxies and related ques- tions in cosmology. In particular, the very broad spectral cov- erage (INTEGRAL) and the possibility for a very long mon- itoring (SMART-1, Chandrayaan-1), coupled to the sophisti- cated modelling, are the key ingredients of the science. De- velopment of new instruments is a natural continuation to the ongoing projects, providing valuable access to the guaranteed time also in the future. The aim is to utilise the advances in in- strument performances carried along with bigger telescopes, larger field-of-view and decreased noise of new systems in the future plans of ESA, NASA and JAXA (IXO, International X-ray Observatory, and Lobster). The specific improvements that are meaningful are: (1) the huge enhancement of sensi- tivity and spectral resolution with IXO, which enables stud- ies of X-ray spectra of Galactic sources with the same qual- ity we nowadays can investigate the solar corona, (2) almost full sky field-of-view in X-rays with moderate spectral res-
olution (Lobster)) giving a freedom to select targets of in- terest and study their temporal and spectral behaviour in all time scales from seconds to months. The systems under de- velopment are: (1) The SIXS instrument for BepiColombo (2) common DPU and onboard software of SIXS and MIXS instruments for BepiColombo, and (3) SQUID readout elec- tronics for the X-ray Spectrometer (XRS) for IXO. The ac- tivities of HESA have resulted in the completion of three space science instruments, and a successful aunch of IN- TEGRAL, SMART-1 and Chandrayaan-1 missions with our working hardware onboard. The scientific use of INTEGRAL resulted in a number of scientific papers published in 2003- 8. SMART-1/XSM made effective observations of the Sun from March 2004 to August 2006. Several refereed papers on the instruments have already been published, and several papers on solar coronal science with very high quality data from XSM/SMART-1 are in preparation, and two PhD theses are just under or close to submission. At present, the scientific utilization of INTEGRAL and SMART-1 continues. Obser- vation programs with other satellites (RXTE, XMM-Newton, Chandra, Suzaku) were continued.
The activities have also evolved and grown to a higher level of collaboration with new plans for instruments and satellites, which combine the expertise and experience of the group and its collaborators. The wide scientific and techno- logical expertise within this framework have made it possible to start planning bigger contributions in international space science programs, e.g. participation at PI level in the next ESA cornerstone mission to Mercury (BepiColombo). We are also involved at Co-PI level in the India-ESA collaborative Moon mission Chandaryaan-1 (launched in 2008 andended in August 2009) with an XSM similar to that of SMART-1.
The in-kind contribution of Finland*s entrance fee to ESO was completed successfully by the Finnish Sampo project, and ESO continued to support the development of ESO Re- flex by our team with one and a half year*s extension with ESO funding. We also submitted as a coordinator an EU col- laborative project proposal (E-SQUID)for the Space Call 3 in December 2009. The goal for the aimed research is to develop a super-sensitive readout electronics with SQUID- technology to space detectors in the X-rays, optical and far infrared/submm wavelengths. The main collaborators in this project plan are VTT, Max Institute, University of Leicester, SRON, and IPHT from Jena, Germany.
2.2 Science topics
2.2.1 The solar corona
The aim of this research is to disentangle the properties of the hot solar corona by analysing the X-ray spectra obtained with our own instruments flying on-board space missions, like XSM/SMART-1 and XSM/Chandrayaan-1. The hot corona of the Sun radiates strongly in X-rays. The solar corona ex-
hibits in apparently random intervals very strong eruptions, which are called flares. Big flares are associated with strong enhancement of electromagnetic emission at all wavelengths, and large amounts of accelerated energetic particles. The eruptions occur most frequently and they are strongest on average during Sunspot maximum. In solar flares and also generally in the solar corona the radiation in X-rays domi- nates, which is due to the high temperature of the ionized gas (plasma). Our research aims at clarifying the physical mech- anism of the eruptions by examining the X-ray spectrum and its variation during flares, and by comparing different flares.
Also time behaviour over longer time span is studied with the aim of studying the changes of the properties of solar corona during the Sunspot (11 years) cycle. The methods include de- veloping improved theoretical models based on extensive new very high quality spectroscopic X-ray data. The observations of the Sun are made with X-ray instruments on-board satel- lites. The most important of the instruments is the Finnish XSM X-ray spectrometer on the ESA*s SMART-1 satellite.
In addition, data from the RHESSI and the GOES satellites are used as complementary sources of information. After the end of SMART-1 operations (September 2006), more similar data has already been received from a Finnish solar monitor on the Indian Chandrayaan-1 mission (launched in Septem- ber 2008 and terminated operation in August 2009), and later, especially, with the Finnish solar monitor SIXS on ESA*s BepiColombo (launch August 2014), which all are projects lead by the HESA group. The data will enable obtaining a thorough new insight in electromagnetic processes and X-ray emission mechanisms in hot coronal plasma of the Sun, and will also form a basis in producing a realistic model database for modelling the X-ray spectra of other stars, with the aim of understanding their coronae.
Figure 4: XSM sensor box (Alha, 2009)
2.2.2 Clusters of galaxies
Our research aims in characterising the thermal and nonther- mal processes in clusters of galaxies. We use this information to derive the distribution of baryonic and dark matter in clus- ters and to constrain the cosmological parameters. We also derive properties of the relativistic electron populations and magnetic fields in clusters. The main analysis tools utilized by us are high resolution imaging and spatially resolved spec- troscopy of the hot intracluster gas. For this work we use X- ray and gamma-ray data of clusters of galaxies obtained with XMM-Newton, Suzaku and INTEGRAL satellites. We have obtained observation time via our own proposals which we combine with the available archival data.
Since clusters of galaxies are massive and hot, they inter- act with the Cosmic Microwave background via the Sunyaev- Zeldovich effect. In a working group of Planck satellite, we are planning the usage of this effect based on the Planck data.
We are participating in a international project IACHEC which aims at studying the cross-calibration of high energy satel- lites. JN is leading the cluster working croup of the project.
Comparison of X-ray measurements of clusters of galaxies allows us to estimate the calibration accuracy of different in- struments. We are currently developing cluster-based calibra- tion tools for the future X-ray missions.
2.3 Development of data analysis software
ESO-connected data analysis activities have also grown sig- nificantly since the beginning of Finland’s membership in 2004. The project, called ESO-Sampo, conducted develop- ment of science data analysis environment for ESO. Four IT professionals worked full-time for the in-kind contribution in the period 1.1.2005- 31.1.2008 in a Tekes-funded project at the Observatory, University of Helsinki, and have contin- ued the same work with partial funding from ESO until the end of September 2009. The main result of the project is the ESO Reflex workflow engine, an advanced science anal- ysis environment which ESO plans to implement as standard ESO software for the reduction of VLT and other ESO data.
HESA team has also participated actively in the preparation of national technology return from ESO. These have already lead to a request from ESO to continue ESO Reflex devel- opment by partial ESO funding, and a parallel development of an application for other sciences and also commercial use with Tekes funding, which continued until September 2009.
Further, future activities from this are (1) a Tekes project for developing a Situation Awareness System using Multidi- mensional Information (MIFSAS), and (2) a proposal to the EU for a collaborative project called Combined Analysis of Multi-Source Astronomical Data (CAMSAD).
2.4 External financing and resources
2009: Man-months of work: 109 Academy of Finland: 110 000e
National Technology Agency: 2 600 000e University of Helsinki: 17 000e
European Southern Observatory: 46 000e
2.5 Tests of learning
Kettula, Kimmo
M.Sc. thesis: Relativistic electron population of the Ophiuchus cluster of galaxies; 2009, University of Helsinki, Department of Astronomy
2.6 Visits abroad
Esko, Eero
MIS Workshop, The Netherlands, 11.–14.5.2009, 4 days
Huovelin, Juhani
BepiColombo project meeting ESOC, Darmstadt, Germany, 26.5.2009, 1 day
BepiColombo SWT meeting, Paris, France, 24.–
28.10.2009, 5 days
EU project preparatory meeting, SRON, The Netherlands, 2.10.2009, 1 day
Korpela, Seppo
BepiColombo meeting, Madrid, Spain, 14.–
16.1.2009, 3 days
Antenna field tests at Stevenage, U.K., 3.–
5.2.2009, 3 days
BepiColombo Mission, 7th MPO Science Work- ing Group Meeting (MPO SWG-7), ESTEC, Newton 2, 6./7. April 2009, 6.–7.4.2009, 2 days
MIXS Team Conference at University of Leices- ter, U.K., 31.5.–3.6.2009, 4 days
EU project preparatory meeting, The Netherlands, 2.10.2009, 1 day
Maisala, Sami
Taverna 2.0 workshop, University of Manchester, U.K., 17.–20.2.2009, 4 days
ESO-Reflex technical meeting, Garching, Ger- many, 23.–24.4.2009, 2 days
ESO Reflex Technical meeting, ESO, Garching, Germany, 7.–9.7.2009, 3 days
Nevalainen, Jukka
IACHEC meeting, Osaka, Japan, 22.–29.4.2009, 8 days
Planck consortium meeting, CNR Conference center, Bologna, Italy, 4.–8.11.2009, 5 days
Oittinen, Tero
Taverna 2.0 workshop, University of Manchester, U.K., 17.–20.2.2009, 4 days
ESO technical discussions, Germany, 23.–
24.4.2009, 2 days Takala, Tuure
Taverna 2.0 workshop, University of Manchester, U.K., 17.–20.2.2009, 4 days
ESO technical discussions, Germany, 23.–
24.4.2009, 2 days Vainio, Rami
EGU 2009, Vienna, Austria, 19.–24.4.2009, 6 days
BepiColombo SWG, ESTEC, Amsterdam, The Netherlands, 6.–7.4.2009, 2 days
BepiColombo project meeting, ESOC, Darmstadt, Germany, 26.5.2009
BepiColombo SWT, Blois, France, 26.–
29.10.2009, 4 days V¨a¨an¨anen, Mikko
Invited AIP conference Talk, Big Island Hawaii, USA, 30.4.–10.5.2009, 11 days
2.7 Membership in scientific and scholarly so- cieties
Huovelin, Juhani
Finnish COSPAR committee, Finland
Research school for astronomy and space physics, Finland, board
Academy of Finland assessor pool, Finland, ex- pert
Finnish Space Committee (ANK), permanent ex- pert
Nevalainen, Jukka
Planck Working Group 5, 30.3.2007–, expert International Astronomical Consortium for High Energy Calibration, 9.5.2007–, expert
Figure 5: Media realisations with 4×106 particles with ρ = 0.55, Gc roughness (upper images) of (from left to right) σ/L = 0.012, l = 0.05,0.25,0.5, and fBm roughness (lower images) ofσ/L = 0.012,H = 0.3,0.5,0.7. Parviainen and Muinonen (2009B1)
3 Planetary System Research
Project number 02525008
Research agreements Academy of Finland Type of research Basic research
Director of research ProfessorMuinonen, Karri
Telephone 19122941
Fax 19122952
E-mail Karri.Muinonen@Helsinki.Fi
Research staffwith a Ph.D. Karri Muinonen, Prof.
Kari Lumme, Prof. emer.
Evgenij Zubko, Ph.D.
Mark Paton, Ph.D.
Phd students Antti Penttil¨a, Lic.S.Sc.
Dagmara Oszkiewicz, M.Sc.
Hannu Parviainen, M.Sc.
Jani Tyynel¨a, M.Sc.
Hannakaisa Lindqvist, M.Sc.
Jarkko Niemel¨a, M.Sc.
Students Tuomo Pieniluoma
Associated scientists Markku Poutanen, Prof. (Finnish Geodetic Institute Lauri Pesonen, Prof.
Jari Valkonen, Prof.
Jouni Peltoniemi, Docent (Finnish Geodetic Institute) Timo Nousiainen, Docent
Jenni Virtanen, Ph.D. (Finnish Geodetic Institute) Mikael Granvik, Ph.D. (University of Hawaii) Johanna Torppa, Ph.D. (Geological Survey of Finland) Jyri N¨ar¨anen, Ph.D. (Finnish Geodetic Institute)
3.1 Research activities
Research within the Planetary-System Research -group (PSR) at the University of Helsinki Observatory entails theo- retical, observational, and experimental studies on key top- ics of solar-system exploration. In fundamental planetary physics, PSR theoretical research is focussed on light scat- tering by single small particles, on multiple scattering by complex media of small particles, and the celestial mechan- ics of the few-body problem. Experiments have been car- ried out to measure backscattering characteristics of particu- late media (scatterometer at the Observatory), to assess the X-ray fluorescence by planetary-regolith analog samples (at the Department of Physical Sciences), and to measure mete- orite spectra in visible and near-infrared wavelengths (at the Geological Survey of Finland and at the Finnish Geodetic In- stitute). Observations have been made using both space-based and ground-based telescopes.
The numerical method for computing coherent backscat- tering by complex particulate media developed at UHO has been successfully applied to polarimetric observations of transneptunian objects (TNOs). Boehnhardt et al. described polarimetry in planetary science, in particular, tying the VLT advances to future needs with ELTs. At ESO/VLT, PSR has continued to participate in polarimetric observations of cometary nuclei: these observations are the first-ever system- atic polarimetric observations of cometary nuclei.
Penttil¨a and Lumme have studied the effects of the prop- erties of porous media on light scattering (Penttil¨a & Lumme, 2009). They have used numerical wave-optical methods for light scattering simulations to asses the effect of porosity on the optical properties of paper coating. Both constant poros-
ity profile and media with porosity contrast between layers at different depths are considered. This can lead to optimal paper coating structures for both brightness and gloss.
Juuti et al. (2009) have studied the spectral properties and surface uniformity of black glass gloss references. Commer- cial glossmeters are usually provided with a gloss reference and in some cases the reference is derived from black glass.
Light reflection from the reference depends both on the com- plex refractive index and on the surface quality, such as the roughness and the cleanness of the black glass. The complex refractive index, as a function of wavelength, was measured with an ellipsometer, and the reflectance at standardized gloss measurement angles was calculated for the case of nonpolar- ized light. Furthermore, the gloss variation of the reference was detected with a diffractive-optical-element-based gloss- meter.
Lindqvist et al. (2009B1) studied light scattering by coated, concave-hull-transformed clusters of spheres and Gaussian-random-sphere particles. Nousiainen et al.
(2009B1) focused on optical modeling of thin calcite flakes using Discrete-Dipole Approximation. Zubko et al. (2009B1) studied light scattering by agglomerated debris particles com- posed of highly absorbing material, and the applicability of DDA to conductive particles. Muinonen et al. (2009B1) in- troduced diffuse scatterers in the ray-optics treatment for light scattering by particles large compared to wavelength.
Tyynel¨a et al. (2009B1) carried out radar-scattering com- putations from spherical and spheroidal particles, as well as clusters of spherical particles in the C-band using the discrete- dipole approximation method (DDA). The results were com- pared to those from exact methods.
Parviainen and Muinonen (2009B1) studied volume and surface shadowing in particulate random media, providing a realistic light-scattering model for rough particulate sur- faces. PSR continued an in-depth study on the interpretation of the SMART-1/AMIE photometry. N¨ar¨anen et al. (2009B1) studied regolith effects in planetary X-ray fluorescence spec- troscopy concentrating on laboratory studies at 1.7 - 6.4 keV.
Huovelin et al. (2009B1) and Fraser et al. (2009B1) de- scribed the Solar Intensity X-ray and particle Spectrometer (SIXS) and Mercury Imaging X-ray Spectrometer (MIXS) onboard the ESA BepiColombo mission to Mercury (launch in 2014). Rothery et al. (2009B1) described forecoming Mer- cury surface and compositional studies using BepiColombo.
In studies of asteroid phase curves, Muinonen et al.
(2009, paper submitted to Icarus) presented methods for the derivation of empirical magnitude systems for asteroid phase curves. Their goal is to develop a new magnitude system for asteroids, revising the two-parameter H, G magnitude system currently adopted by IAU.
Establishing links between asteroids and meteorites is problematic. Meteorites allow us to peer inside asteroids but which asteroids are we looking at? Reflectance spectra mea- surements are a popular remote sensing technique of asteroids
Figure 6: Lauri Jetsu and Karri Muinonen at the Observatory 175h anniversary reception, November 2009 (Photo: Eva Isaksson)
as they are relatively easy to do and provide information on composition. These can then be compared with reflectance spectra measurements of meteorites to find a match. How- ever, reflectance spectra measurements of asteroids are from the surface and this may be unrepresentative of the interior due to surface effects and geological processes. Reflectance spectra of 27 meteorites, representing undifferentiated (C, H, L, LL, and E) to differentiated meteorites, were obtained us- ing a spectrometer at the Geological Survey of Finland. Fea- tures in the reflectance spectra were explored by Paton et al. (paper in preparation) to determine if they revealed diag- nostic features among the various meteorite groups and sub- groups, if they correlated with meteorite physical properties (e.g. mineralogy, density, porosity, or susceptibility) or with weathering or shock degree. Classification methods, using these non-destructive physical and spectral property measure- ments of meteorites, are developed for possible application to future remote sensing of asteroids and to strengthen the link between meteorites and asteroids.
Oszkiewicz et al. completed a paper (D. Oszkiewicz, K.
Muinonen, J. Virtanen, M.Granvik, Meteoritics and Plane- tary Science, in press, 2009) that introduces a new Markov- Chain Monte-Carlo orbital ranging method for poorly ob- served single-apparition asteroids with two or more astro- metric observations. The method has been applied to near- Earth, main-belt, and transneptunian objects. Obtained dis- tributions of orbital elements can then serve as a base in Earth impact probability computation, dynamical classifica- tion, ephemeris prediction, linking between apparitions prob- lems, and in other applications.
Granvik et al. M. Granvik, J. Virtanen, D. Oszkiewicz, K.
Muinonen, Meteoritics and Planetary Science, in press, 2009) describe an open-source asteroid-orbit-computation software package called OpenOrb. In addition to the well-known least-squares method, OpenOrb contains both Monte-Carlo and Markov-Chain Monte-Carlo versions of the statistical or- bital ranging method (Ranging) based on well-established Bayesian inversion theory. As an example, OpenOrb was used to search for candidate retrograde objects similar to 2008 KV42 in the known population of transneptunian ob- jects.
PSR contributed to the preparation of the ESA astromet- ric cornerstone mission Gaia (launch in 2012): this entailed orbital-inverion software delivery to the Gaia Data Process- ing and Analysis Pipeline (DPAC) and further development of Markov-Chain Monte Carlo methods for inversion of fore- coming Gaia photometry for asteroid spin and shape charac- teristics. Preparations continued for a successful competition of the Marco Polo near-Earth-object sample return mission within the ESA Cosmic Vision Programme, with PSR repre- sented in the ESA Science Study Team of the mission.
3.2 External financing and resources
2009: Man-months of work: 100
Academy of Finland, ’Light Scattering by Solar- System Small Particles’:
117 740e
European Commission, ’European Leadership in Space Astrometry’ (ELSA)’: 62 000e
Tekes intelligent production technologies project : 153 000e
Tekes forest cluster project Re-engineering paper:
21 000e
3.3 Tests of learning
N¨ar¨anen, Jyri
Ph.D. thesis: Multiwavelength studies of regolith effects in planetary remote sensing; 2009, University of Helsinki, Department of Astronomy
Niemel¨a, Jarkko
M.Sc. thesis: Asteroid polarimetry: review and new observations; 2009, University of Helsinki, De- partment of Astronomy
3.4 Visits abroad
Muinonen, Karri
ELSA Mid-Term-Review meeting, Brussels, Bel- gium, 1.–5.2.2009, 5 days
Gaia GREAT network kick-off meeting, Cam- bridge, U.K., 25.–29.3.2009
1st Planetary Defense Conference, Granada, Spain, 26.4.–1.5.2009, 6 days
GAIA CU4 meeting, Turin, Italy, 28.–30.5.2009, 3 days
IAU General Meeting, Rio de Janeiro, Brazil, 2.–
15.8.2009, 14 days
Marco Polo mission meeting, Paris, France, 17.–
21.5.2009, 5 days
International Symposium on Atmospheric Light Scattering and Remote Sensing, Xian, China, 13.- 17.7.2009, 5 days
Marco Polo Science Study team Meeting, ESTEC, The Netherlands, 9.–11.9.2009, 3 days
Marco Polo Science study team -meeting, ES- TEC/ESA, The Netherlands, 22.–24.9.2009
ELSA School ”The Techniques of Gaia”, Heidel- berg, Germany, 27.9.–3.10.2009, 7 days
Marco Polo -mission Science Study Team meet- ing, Paris, France, 30.11.–2.12.2009: 3 days
Niemel¨a, Jarkko
Observations with NOT-telesscope, La Palma, Spain, 28.7.–2.8.2009, 6 days,
N¨ar¨anen, Jyri
EGU General Assembly 2009, Wien, Austria, 19.–25.4.2009, 7 days
Soft X-ray fluorescence spectroscopy workshop, ESTEC,The Netherlands, 1.–2.9.2009
BepiColombo 6th SWT meeting, Blois, France, 26.–30.10.2009, 5 days
Oszkiewicz, Dagmara
ELSA Mid-Term-Review meeting, Brussels, Bel- gium, 1.–4.2.2009, 4 days
Workshop dealing with technical concerns im- posed by Gaia and DPCC host frame work, Paris Ob- servatory, France, 16.–18.2.2009, 3 days
1. ELSA secondment, Paris, France and 2.
GREAT Kickoff meeting, Cambridge, U.K., 14.–
27.3.2009, 14 days
1st Planetary Defense Conference, Granada, Spain, 23.4.–3.5.2009, 11 days
DPAC CU4 -meeting 7 28-29 May 2009 INAF, Osservatorio Astronomico di Torino, Italy, 27.–
30.5.2009, 4 days
International Astronomical Union general assem- bly, Rio de Janeiro, Brazil 20.7.–15.8.2009, 26 days
International conference of Young Astronomers (ICYA), Krakow, Poland, 6.–19.9.2009, 14 days
ELSA School on the Techniques of Gaia, Heidel- berg, Germany, 27.9.–3.10.2009, 7 days
Gaia Coordination Unit 4 ”Object processing”
The 8th Meeting, Lohrmann Observatory, Dresden, Germany, 11.–16.11.2009, 6 days
Parviainen, Hannu
EGU 2007, Austria, 18.–26.4.2009, 9 days Zubko, E.
Scientific collaboration with Ukrainian colleagues Prof. Yu. Shkuratov and Dr. D. Petrov, Ukraine, 24.7.–
17.8.2009, 25 days
Scientific discussion with Dr. G. Videen at Amy Research Laboratory, (Adelphi, MD,USA) and partici- pation in 41st annual meeting of the Division for Plane- tary Sciences of the American Society, Fajardo, Puerto Rico, USA, 29.9.–10.10.2009, 12 days
3.5 Papers read at scientific conferences, sym- posia, meetings etc.
Oszkiewicz, Dagmara
”Asteroid orbits with Gaia using Markov- Chain Monte-Carlo ranging”, D. A. Oszkiewicz, K.Muinonen, J.Virtanen, M.Granvik (Granada, Spain, 27.–30.4.2009), poster
”Time evolution of collision probabilities for 2004 AS1 2008 TC3 2009 DD45.” D. A. Oszkiewicz, K.Muinonen, J.Virtanen, M.Granvik, IAU‘s XXVII GENERAL ASSEMBLY, Rio de Janeiro (Brazil)3.–
14.8.2009, poster
”Time evolution of collision probabilities for 2004 AS1 2008 TC3 2009 DD45.” D. A. Oszkiewicz, K.Muinonen, J.Virtanen, M.Granvik, The Interna- tional Conference of Young Astronomers (ICYA) 7.–
13.09.2009 Krakow, Poland, poster
”Time evolution of collision probabilities for 2004 AS1 2008 TC3 2009 DD45.” D. A. Oszkiewicz, K.Muinonen, J.Virtanen, M.Granvik, FinCOSPAR 3.–
5.9.2009 Rokua National Park, poster ”Asteroid rang- ing with Markov-Chain Monte-Carlo” D. A. Os- zkiewicz, K. Muinonen, J.Virtanen, M.Granvik (In- stitut Seminar, Astronomical Observatory, Poznan, Poland, 8.1.2009)
”Asteroid orbital inversion using statistical meth- ods”, D. A. Oszkiewicz, K. Muinonen (Brussels, Bel- gium, 2.2.2009)
”Asteroid orbits with Gaia using MCMC rang- ing” D. A. Oszkiewicz, K. Muinonen, J. Virtanen, M.
Granvik (Geophysics Days, 3.–14.5.2009, Helsinki)
”Asteroid orbits with Gaia using MCMC rang- ing” D. A. Oszkiewicz, K. Muinonen, J. Virtanen, M.
Granvik (CU4#7 meeting, 29.05.2009, Torino)
”MCMC orbital ranging and its applications”, D.
A. Oszkiewicz, K. Muinonen, J. Virtanen, M. Granvik , ELSA School, Heideberg 28.9.–2.10.2009
”MCMC ranging – convergence diagnostics”, D. A. Oszkiewicz, PSR group seminar presentation 5.10.2009, Helsinki
”Mets¨ahovi-Kumpula project, a platform for si- multaneous observation of meteors and air-plane track- ing” D. A. Oszkiewicz, Jyri Naranen, 9.11.2009, PSR group seminar, Helsinki
”DU456 progress report” D. A. Oszkiewicz, K. Muinonen, CU4#8 meeting, Dresden (12.–
13.11.2009), Germany
Penttil¨a, Antti
”Simulation of optical properties and NFC-filler structures”. Seminar of Intelligent and Resource- Efficient Production Technologies (EffTech) pro- gramme, Espoo, Dipoli Congress Centre, 6.9.2009
3.6 Visiting academics
Muinonen, Karri
Dr. Harrison Schmitt, Apollo 17 Astronaut, April 16, 2009
Prof. Nicolas Thomas, University of Bern, March 4–7, 2009
Prof. Claes-Ingvar Lagerkvist, Uppsala Univer- sity, March 6, 2009
Dr. Michael Weiler, Paris Observatory, March 2–
13, 2009
Dr. Mikael Granvik, University of Hawaii, May 7, 2009
Mr. Benoit Frezouls, CNES, France, June 15–19, 2009
Mr. Christophe Ordenovic, Observatoire de la Cote d’Azur, June 15–19, 2009
Dr. Maria Gritsevich, ESA/ESTEC, November 16–17, 2009
3.7 Membership in scientific and scholarly so- cieties
Muinonen, Karri
International Astronomical Union, Commission 20 Organizing Committee, 2006–, France
ELSA Steering Committee (European Leadership in Space Astrometry), 1.10.2006–, Sweden
International Astronomical Union, Task Group on Asteroid Magnitudes, 2006–, France
International Astronomical Union, Task Group on Asteroid Polarimetric Albedo Calibration, 2006–, France
Marco Polo Science Study Team, ESA, 2007–, France
International Astronomical Union, Task Group on Geophysical and Geological Properties of Asteroids and Cometary Nuclei, 2008–, France, chair
3.8 Refereeing and Other Publishing Activities
Muinonen, Karri Icarus, USA, referee
Planetary and Space Science, The Netherlands, referee
Astronomy and Astrophysics, France, referee Journal of Quantitative Spectroscopy & Radiative Transfer, referee
Figure 7: Students at the Observatory lecture hall, November 2009 (Photo: Eva Isaksson)
4 Lectures in 2009
Course (English) Course (Finnish)
spring term
basic studies perusopinnot
Universe now Maailmankaikkeus nyt (lectured in English) Universe now Maailmankaikkeus nyt (lectured in Finnish) Universe now Maailmankaikkeus nyt (lectured in Swedish) Basics of observational astronomy I Havaitsevan t¨ahtitieteen peruskurssi I
Basic astronomy T¨ahtitieteen perusteet
Practical methods in astronomy T¨ahtitieteen k¨ayt¨ann¨on menetelmi¨a
subject studies aineopinnot
Structure of the Milky Way Linnunradan rakenne
advanced studies syvent¨av¨at opinnot
Astrobiology Astrobiologia
Scattering of light on small particles II Valon sironta pienhiukkasista II Planetary geophysics Planetaarinen geofysiikka Advanced course in dynamics Dynamiikan jatkokurssi Infrared astronomy Infrapunat¨ahtitiede Submillimetre astronomy Alimillimetrit¨ahtitiede
Magnetohydrodynamics Magnetohydrodynamiikka
other muut
Climate changes of planet Earth Planeetta Maan ilmastonvaihtelut
Telling about astronomy – a course on Kerro t¨ahtitieteest¨a – populaarikirjoittamisen
popularization kurssi
Introduction to project management Johdatus projektity¨oh¨on
Chronology: history and calendars Ajanlasku: historiaa ja kalentereita
seminars seminaarit
Astrophysics seminar Astrofysiikan seminaari
Planetary system research seminar Planeettakunnan tutkimusseminaari autumn term
basic studies perusopinnot
Universe now Maailmankaikkeus nyt (lectured in Finnish) Basics of observational astronomy II Havaitsevan t¨ahtitieteen peruskurssi II
Basic astronomy T¨ahtitieteen perusteet
subject studies aineopinnot
X-ray analysis of galaxy clusters Galaksijoukkojen r¨ontgenanalyysi Structure and evolution of stars T¨ahtien rakenne ja kehitys Basic course in astrophysics Astrofysiikan peruskurssi Physics of the Solar system Aurinkokunnan fysiikka
advanced studies syvent¨av¨at opinnot
High energy astrophysics Suurenergia-astrofysiikkaa Interstellar medium T¨ahtienv¨alinen aine
lecture series on astrobiology – astrobiologian luentosarja
Interferometry at radio and infrared Radio- ja infrapuna-alueen interferometria wavelengths
other muut
Introduction to astrobiology Johdatus astrobiologiaan Introduction to expert tasks Johdatus asiantuntijateht¨aviin Introduction to applications of Johdatus pallot¨ahtitieteen sovelluksiin
spherical astronomy
seminars seminaarit
Astrophysics seminar Astrofysiikan seminaari
Planetary system research seminar Planeettakunnan tutkimusseminaari
5 Library
Librarian Eva Isaksson, M.Sc.
E-mail astro-library@helsinki.fi
5.1 Library Merger
The Observatory library will merge with the Kumpula Cam- pus Library in January 2010. To prepare the merger, a work- group consisting of librarians and astronomers was set up to decide on best practices and priorities.
The Observatory library collection is exceptional and pro- vides a comprehensive view on two centuries of astronomical research and publishing activities. The Kumpula Campus li- brary is a modern library serving research, teaching and stud- ies. It has limited space available for older collections no longer in active use, thus it is a major challenge to preserve these historical collections.
The transfer of books to Kumpula was started in Novem- ber 2009, and serials will be transferred in early 2010.
Figure 8: Books awaiting transfer
5.2 LISA VI Conference
The Library and Information Services in Astronomy (LISA) conferences, arranged every 4th year, bring together astron- omy librarians, publishers and information specialists from all over the world.
The librarian acts as co-chair of the Scientific Organizing Committee of the next LISA conference to be held in Pune, India in February 14-17, 2010.
5.3 Membership in scientific and scholarly so- cieties
Isaksson, Eva
Library and Information Services in Astronomy (LISA) VI SOC, co-chair
6 Observatory Board 2007–2009
Director Doc. Lauri Jetsu
Professors Prof. Kalevi Mattila
Prof. Karri Muinonen (starting 8.4.2009) Staff
Doc. Mika Juvela
Prof. Karri Muinonen (until 8.4.2009) Doc. Juhani Huovelin (starting 8.4.2009)
Students
Suvi Jentze (until 26.8.2008) Karri Koljonen (until 7.1.2009) Jussi Aaltonen (starting 26.8.2009) Merli Lahtinen (starting 7.1.2009)
Figure 9: Some participants of the last Observatory Board meeting 15.12.2009. From left to right: Hannikainen, Aaltonen, Huovelin, Jetsu, Toriseva, Muinonen. (Photo: Jenni Toriseva)