Helmi, Prof. Amina
Amina Helmi (1970) is Professor of Dynamics, Structure and Formation of the Milky Way. Helmi wrote a groundbreaking PhD thesis (for which she was awarded the 2004 Christiaan Huygens Prize), shedding new light on the history and formation of the Milky Way by stating that it probably gradually merged with smaller galaxies. Helmi is searching for these separate galaxies (‘fossils’) and is thus a sort of astro-archaeologist, using the information from star fossils to reconstruct the formation of the Milky Way.
Spinozalaureaat 2019 - Amina Helmi
New insights - Formation of the Milky Way
This day places the astronomy in a different light
Helmi about the end of the world
Helmi has been awarded a number of prestigious grants, including an NWO VIDI grant in 2003 and an ERC Starting Grant from the EU in 2009. She is an active member of numerous networks. In 2017 she has been elected as member of the KNAW, the Royal Netherlands Academy of Arts and Sciences. Helmi is closely involved with the GAIA telescope, launched in 2013, which is providing very precise measurements to chart the Milky Way. II 2014 a team of scientists, including Helmi, published the first map of the spatial distribution of the mysterious matter in the almost empty space between stars, in Science. In 2015 she was awarded a VICI grant for her research, and in 2017 an NWO grant. In 2018 she and her research group were one of the first to be given the opportunity to study a second set of data from Gaia missions.
The Milky Way has always been viewed as a relatively unchanging spiral galaxy. Research by Helmi and her colleagues has fundamentally changed that view. By analysing the movements and properties of millions of stars, they discovered the remnants of smaller galaxies that were swallowed up by the Milky Way in the distant past.
These so-called ‘stellar streams’ are fossilized traces of cosmic collisions that took place in the past. In this way, stellar streams provide a detailed record of the galaxy’s merger history.
One of Helmi’s most influential contributions was the discovery of Gaia-Enceladus, a large galaxy that collided with the young Milky Way around ten billion years ago. This discovery, made possible by data from the European space mission Gaia, is considered a milestone in our understanding of the formation of our galaxy.
In 2019 Helmi was awarded the Spinoza Prize, the highest academic award in the Netherlands. In 2026 she was been awarded the prestigious Kavli Prize in Astrophysics. Helmi received the prize alongside Vasily Belokurov (University of Cambridge) and Rodrigo Ibata (Université de Strasbourg). According to the Kavli Prize Committee, the research by Helmi and her co-winners has ‘fundamentally changed our understanding of how large galaxies such as the Milky Way formed.’ Galaxies are no longer seen as static systems, but as dynamic structures that are constantly changing due to cosmic interactions.
Previously in the news
2026
Wempe,
E., White, S. D. M., Helmi, A., Lavaux, G.,
& Jasche, J. (2026). The mass distribution in and around
the Local Group. Nature Astronomy. https://doi.org/10.1038/s41550-025-02770-w
2025
Bayer,
M., Starkenburg, E., Thomas, G. F., Martin, N.
F., Helmi, A., Byström, A., de Boer, T.,
Fernández Alvar, E., Gwyn, S., Ibata, R., Jablonka, P.,
Kordopatis, G., Matsuno, T., McConnachie, A. W., Medina, G.
E., Rusterucci, S., Sánchez-Janssen, R., Sestito,
F., & Viswanathan, A. (2025). A Pristine-UNIONS view on
the Galaxy: Kinematics of the distant spur feature of the
Sagittarius stream traced by blue horizontal branch stars.
Astronomy & Astrophysics, 701,
Article A117. https://doi.org/10.1051/0004-6361/202554131
Ceccarelli,
E., Massari, D., Palla, M., Mucciarelli, A., Bellazzini, M.,
& Helmi, A. (2025). A Walk on the Retrograde Side
(WRS) project: II. Chemistry to disentangle in situ and accreted
components in Thamnos. Astronomy and
Astrophysics, 704, Article A180. https://doi.org/10.1051/0004-6361/202556685
Dodd,
E., Ruiz-Lara, T., Helmi, A., Gallart,
C., Callingham, T. M., Cassisi, S.,
Fernández-Alvar, E., & Surot, F. (2025).
Characterisation of local halo building blocks: Thamnos and
Sequoia. Astronomy & Astrophysics,
698, Article A277. https://doi.org/10.1051/0004-6361/202451978
Dodd,
E., Matsuno, T., Helmi, A., Balbinot,
E., Callingham, T. M., Starkenburg,
E., Woudenberg, H. C., & Ruiz-Lara, T.
(2025). Chemical characterisation of small substructures in
the local stellar halo. Astronomy &
Astrophysics, 700, Article A154. https://doi.org/10.1051/0004-6361/202554252
González-Koda,
Y. K., Ruiz-Lara, T., Gallart, C., Ceccarelli,
E., Dodd, E., Fernández-Alvar, E., Cassisi, S.,
Surot, F., Aguado-Agelet, F., Massari, D., Monelli,
M., Callingham, T. M., Helmi, A.,
Aznar-Menargues, G., Mirabal, D., Rivero, A., & Queiroz, A. B.
(2025). Chronology of our Galaxy from Gaia
colour-magnitude diagram fitting (ChronoGal): III. Age and
metallicity distribution of Gaia-Sausage-Enceladus stars near the
Sun. Astronomy and Astrophysics,
704, Article A259. https://doi.org/10.1051/0004-6361/202554272
Fernández-Alvar,
E., Ruiz-Lara, T., Gallart, C., Cassisi, S., Surot,
F., González-Koda, Y. K., Callingham, T. M.,
Queiroz, A. B., Battaglia, G., Thomas, G., Chiappini, C., Hill,
V., Dodd, E., Helmi, A., Aznar-Menargues,
G., De La Cueva, A., Mirabal, D., Quintana-Ansaldo, M., &
Rivero, A. (2025). Chronology of our Galaxy from Gaia
colour–magnitude diagram fitting (ChronoGal) : II.
Unveiling the formation and evolution of the kinematically selected
thick and thin discs. Astronomy and
Astrophysics, 704, Article A258. https://doi.org/10.1051/0004-6361/202553814
Callingham,
T. M., & Helmi, A. (2025). Group
accretion in Milky Way-like stellar haloes.
Astronomy & Astrophysics, 700,
Article A175. https://doi.org/10.1051/0004-6361/202554966
Lindsay,
C. J., Hon, M., Ong, J. M. J., García, R. A.,
Palakkatharappil, D. B., Yu, J., Li, T., Ruiz-Lara, T., &
Helmi, A. (2025). Precise Asteroseismic Ages for the
Helmi Streams. Astrophysical Journal,
989(2), Article 189. https://doi.org/10.3847/1538-4357/adeb56
Nizovkina,
M., Larsen, S. S., Brown, A. G. A., & Helmi, A.
(2025). Refining open cluster parameters with Gaia XP
metallicities. Astronomy &
Astrophysics, 703, Article A100. https://doi.org/10.1051/0004-6361/202555437
Woudenberg,
H. C., & Helmi, A. (2025). The chaos
induced by the Galactic bar on the orbits of nearby halo
stars. Astronomy & Astrophysics,
700, Article A240. https://doi.org/10.1051/0004-6361/202555672
Wempe,
E., Helmi, A., White, S. D. M., Jasche, J.,
& Lavaux, G. (2025). The effect of environment on the
mass assembly history of the Milky Way and M31.
Astronomy & Astrophysics, 701,
Article A178. https://doi.org/10.1051/0004-6361/202553744
Montelius,
M., Starkenburg, E., Woudenberg, H.
C., Angrilli Muglia, A., Ardern-Arentsen, A.,
Viswanathan, A., Byström, A., Helmi, A.,
Martin, N., Matsuno, T., Navarrete, C., & Navarro,
J. (2025). The metal-poor tail of the APOGEE survey : I.
Uncovering [Fe/H] < –2.5 stars from the inner Galaxy to
the Magellanic Clouds. Astronomy and
Astrophysics, 704, Article A44. https://doi.org/10.1051/0004-6361/202556198
Matsuno,
T., Kemp, A., Tanikawa, A., Shariat, C. E., El-Badry, K. J.,
Dodd, E., Helmi, A., Koch-Hansen, A. J.,
Yamaguchi, N., & Yan, H. (2025). Unevolved Li-rich stars
at low metallicity: A possible formation pathway through
novae. Astronomy & Astrophysics,
699, Article A171. https://doi.org/10.1051/0004-6361/202554264
2024
Koop,
O., Antoja, T., Helmi, A., Callingham, T.
M., & Laporte, C. F. P. (2024). Assessing the
robustness of the Galactic rotation curve inferred from the Jeans
equations using Gaia DR3 and cosmological simulations.
Astronomy & Astrophysics, 692,
Article A50. https://doi.org/10.1051/0004-6361/202450911
Gallart,
C., Surot, F., Cassisi, S., Fernández-Alvar, E., Mirabal, D.,
Rivero, A., Ruiz-Lara, T., Santos-Torres, J., Aznar-Menargues, G.,
Battaglia, G., Queiroz, A. B., Monelli, M., Vasiliev, E.,
Chiappini, C., Helmi, A., Hill, V., Massari, D., &
Thomas, G. F. (2024). Chronology of our Galaxy from Gaia
colour-magnitude diagram fitting (ChronoGal): I. the formation and
evolution of the thin disc from the Gaia Catalogue of Nearby
Stars. Astronomy & Astrophysics,
687, Article A168. https://doi.org/10.1051/0004-6361/202349078
Wempe,
E., Lavaux, G., White, S. D. M., Helmi, A.,
Jasche, J., & Stopyra, S. (2024). Constrained
cosmological simulations of the Local Group using Bayesian
hierarchical field-level inference. Astronomy
& Astrophysics, 691, Article A348. https://doi.org/10.1051/0004-6361/202450975
Gaia
Collaboration, Panuzzo, P., Mazeh, T., Arenou, F., Holl, B.,
Caffau, E., Jorissen, A., Babusiaux, C., Balbinot,
E., Helmi, A., & Khanna, S. (2024).
Discovery of a dormant 33 solar-mass black hole in
pre-release Gaia astrometry. Astronomy &
Astrophysics, 686, Article L2. https://doi.org/10.1051/0004-6361/202449763
Euclid
Collaboration, Mellier, Y., Abdurro’uf, Barroso, J. A.
A., Balbinot, E., Belikov, A. N.,
Buddelmeijer, H., Caputi, K. I.,
Corcho-Caballero, P., Dayal, P.,
Dröge, B., Helmi, A., Koopmans, L.
V. E., La Marca, A., Nagam, B.
C., Nutma, T., Peletier, R.
F., Saifollahi, T., Shulevski,
A., ... Williams, O. R. (2024).
Euclid. I. Overview of the Euclid mission.
arXiv. https://doi.org/10.48550/arXiv.2405.13491
Callingham,
T. M., & Helmi, A. (2024). Filling in
the blanks: A method to infer the substructure membership and
dynamics of 5D stars. Astronomy &
Astrophysics, 690, Article A98. https://doi.org/10.1051/0004-6361/202450745
Woudenberg,
H. C., & Helmi, A. (2024). First
measurement of the triaxiality of the inner dark matter halo of the
Milky Way. Astronomy &
Astrophysics, 691, Article A277. https://doi.org/10.1051/0004-6361/202451743
Gaia
Collaboration, Krone-Martins, A., Ducourant, C., Galluccio, L.,
Delchambre, L., Oreshina-Slezak, I., Teixeira, R., Braine, J.,
Khanna, S., & Helmi, A. (2024). Gaia Focused
Product Release: A catalogue of sources around quasars to search
for strongly lensed quasars. Astronomy &
Astrophysics, 685, Article A130. https://doi.org/10.1051/0004-6361/202347273
Matsuno,
T., Starkenburg, E., Balbinot,
E., & Helmi, A. (2024). Improving
metallicity estimates for very metal-poor stars in the Gaia DR3
GSP-Spec catalog. Astronomy &
Astrophysics, 685, Article A59. https://doi.org/10.1051/0004-6361/202245762
Koop,
O., & Helmi, A. (2024). Testing MOND
using the dynamics of nearby stellar streams.
Astronomy & Astrophysics, 689,
Article A57. https://doi.org/10.1051/0004-6361/202348211
Balbinot,
E., Dodd, E., Matsuno, T., Lardo, C.,
Helmi, A., Panuzzo, P., Mazeh, T., Holl, B., Caffau, E.,
Jorissen, A., Babusiaux, C., Gavras, P., Wyrzykowski, L., Eyer, L.,
Leclerc, N., Bombrun, A., Mowlavi, N., Seabroke, G. M.,
Cabrera-Ziri, I., ... Starkenburg, E. (2024).
The 33 M black hole Gaia BH3 is part of the disrupted ED-2
star cluster. Astronomy &
Astrophysics, 687, Article L3. https://doi.org/10.1051/0004-6361/202450425
Grønnow,
A., Fraternali, F., Marinacci, F.,
Pezzulli, G., Tolstoy, E., Helmi,
A., & Brown, A. G. A. (2024). The density of the
Milky Way’s corona at z ≈ 1.6 through ram pressure
stripping of the Draco dSph galaxy. Monthly
Notices of the Royal Astronomical Society,
528(2), 3009-3027. https://doi.org/10.1093/mnras/stae073
2023
The
WEAVE Instrumentation & Survey Consortia, Jin,
S., Trager, S. C., Dalton, G. B., Aguerri, J.
A. L., Drew, J. E., Falcón-Barroso, J., Gänsicke, B. T.,
Hess, K. M., Balbinot, E., Helmi,
A., Matsuno, T., Peletier, R.
F., Starkenburg, E., & Tolstoy,
E. (2024). The wide-field, multiplexed, spectroscopic
facility WEAVE: Survey design, overview, and simulated
implementation. Monthly Notices of the Royal
Astronomical Society, 530(3), 2688-2730. https://doi.org/10.1093/mnras/stad557
Tolstoy,
E., Skúladóttir, Á., Battaglia, G., Brown, A.
G. A., Massari, D., Irwin, M. J., Starkenburg,
E., Salvadori, S., Hill, V., Jablonka, P., Salaris, M., van
Essen, T., Olsthoorn, C., Helmi, A., & Pritchard,
J. (2023). A 3D view of dwarf galaxies with Gaia and
VLT/FLAMES. I. The Sculptor dwarf spheroidal.
Astronomy & Astrophysics, 675,
Article A49. https://doi.org/10.1051/0004-6361/202245717
Woudenberg,
H. C., Koop, O., Balbinot,
E., & Helmi, A. (2023).
Characterization and dynamics of the peculiar stream Jhelum:
A tentative role for the Sagittarius dwarf galaxy.
Astronomy & Astrophysics, 669,
Article A102. https://doi.org/10.1051/0004-6361/202243266
Balbinot,
E., Helmi, A., Callingham,
T., Matsuno, T., Dodd, E.,
& Ruiz-Lara, T. (2023). ED-2: A cold but not so
narrow stellar stream crossing the solar neighbourhood.
Astronomy & Astrophysics, 678,
Article A115. https://doi.org/10.1051/0004-6361/202347076
Babusiaux,
C., Fabricius, C., Khanna, S., Muraveva, T., Reylé, C., Spoto,
F., Vallenari, A., Luri, X., Arenou, F., Álvarez, M. A.,
Anders, F., Antoja, T., Balbinot, E., Barache, C.,
Bauchet, N., Bossini, D., Busonero, D., Cantat-Gaudin, T.,
Carrasco, J. M., ... Weiler, M. (2023). Gaia Data Release 3:
Catalogue validation. Astronomy &
Astrophysics, 674, Article A32. https://doi.org/10.1051/0004-6361/202243790
Gaia
Collaboration, Creevey, O. L., Sarro, L. M., Lobel, A., Pancino,
E., Andrae, R., Smart, R. L., Clementini, G., Balbinot,
E., Helmi, A., & Khanna, S. (2023).
Gaia Data Release 3: A golden sample of astrophysical
parameters. Astronomy &
Astrophysics, 674, Article A39. https://doi.org/10.1051/0004-6361/202243800
Gaia
Collaboration, Recio-Blanco, A., Kordopatis, G., de Laverny, P.,
Palicio, P. A., Spagna, A., Spina, L., Katz, D., Balbinot,
E., Helmi, A., & Khanna, S. (2023).
Gaia Data Release 3: Chemical cartography of the Milky
Way. Astronomy & Astrophysics,
674, Article A38. https://doi.org/10.1051/0004-6361/202243511
Gaia
Collaboration, Drimmel, R., Romero-Gomez, M., Chemin, L., Ramos,
P., Poggio, C. E., Ripepi, V., Andrae, R., Khanna, S.,
Balbinot, E., & Helmi, A. (2023).
Gaia Data Release 3: Mapping the asymmetric disc of the Milky
Way. Astronomy & Astrophysics,
674, Article A37. https://doi.org/10.1051/0004-6361/202243797
Gaia
Collaboration, De Ridder, J., Ripepi, V., Aerts, C., Palaversa, L.,
Eyer, L., Holl, B., Audard, M., Balbinot, E.,
Helmi, A., & Khanna, S. (2023). Gaia Data Release
3: Pulsations in main sequence OBAF-type stars.
Astronomy & Astrophysics, 674,
Article A36. https://doi.org/10.1051/0004-6361/202243767
Gaia
Collaboration, Schultheis, M., Zhao, H., Zwitter, T., Marshall, D.
J., Drimmel, R., Frémat, Y., Bailer-Jones, C. A. L.,
Balbinot, E., Helmi, A., & Khanna, S.
(2023). Gaia Data Release 3: Exploring and mapping the
diffuse interstellar band at 862 nm. Astronomy
& Astrophysics, 674, Article A40. https://doi.org/10.1051/0004-6361/202243283
Gaia
Collaboration, Vallenari, A., Brown, A. G. A., Prusti, T., de
Bruijne, J. H. J., Arenou, F., Babusiaux, C., Biermann, M.,
Balbinot, E., Helmi, A., & Khanna, S.
(2023). Gaia Data Release 3: Summary of the content and
survey properties. Astronomy &
Astrophysics, 674, Article A1. https://doi.org/10.1051/0004-6361/202243940
Gaia
Collaboration, Arenou, F., Babusiaux, C., Barstow, M. A., Faigler,
S., Jorissen, A., Kervella, P., Mazeh, T., Balbinot,
E., Helmi, A., & Khanna, S. (2023).
Gaia Data Release 3: Stellar multiplicity, a teaser for the
hidden treasure. Astronomy &
Astrophysics, 674, Article A34. https://doi.org/10.1051/0004-6361/202243782
Gaia
Collaboration, Montegriffo, P., Bellazzini, M., Angeli, F., Andrae,
R., Barstow, M. A., Bossini, D., Bragaglia, A., Balbinot,
E., Helmi, A., & Khanna, S. (2023).
Gaia Data Release 3: The Galaxy in your preferred colours:
Synthetic photometry from Gaia low-resolution spectra.
Astronomy & Astrophysics, 674,
Article A33. https://doi.org/10.1051/0004-6361/202243709
Dodd,
E., Callingham, T. M., Helmi,
A., Matsuno, T., Ruiz-Lara,
T., Balbinot, E., & Lövdal,
S. (2023). Gaia DR3 view of dynamical substructure in
the stellar halo near the Sun. Astronomy &
Astrophysics, 670, Article L2. https://doi.org/10.1051/0004-6361/202244546
Gaia
Collaboration, David, P., Mignard, F., Hestroffer, D., Tanga, P.,
Spoto, F., Berthier, J., Pauwels, T., Helmi, A., &
Khanna, S. (2023). Gaia Focused Product Release: Asteroid
orbital solution. Properties and assessment.
Astronomy & Astrophysics, 680,
Article A37. https://doi.org/10.1051/0004-6361/202347270
Gaia
Collaboration, Weingrill, K., Mints, A., Castaneda, J.,
Kostrzewa-Rutkowska, Z., Davidson, M., De Angeli, F., Hernandez,
J., Helmi, A., & Khanna, S. (2023). Gaia
Focused Product Release: Sources from Service Interface Function
image analysis. Half a million new sources in omega
Centauri. Astronomy &
Astrophysics, 680, Article A35. https://doi.org/10.1051/0004-6361/202347203
Gaia
Collaboration, Trabucchi, M., Mowlavi, N., Lebzelter, T.,
Lecoeur-Taibi, I., Audard, M., Eyer, L., Garcia-Lario, P.,
Helmi, A., & Khanna, S. (2023). Gaia Focused
Product Release: Radial velocity time series of long-period
variables. Astronomy &
Astrophysics, 680, Article A36. https://doi.org/10.1051/0004-6361/202347287
Gaia
Collaboration, Schultheis, M., Zhao, H., Zwitter, T., Bailer-Jones,
C. A. L., Carballo, R., Sordo, R., Drimmel, R., Helmi,
A., & Khanna, S. (2023). Gaia Focused Product
Release: Spatial distribution of two diffuse interstellar
bands. Astronomy & Astrophysics,
680, Article A38. https://doi.org/10.1051/0004-6361/202347103
Viswanathan,
A., Starkenburg, E., Koppelman, H.
H., Helmi, A., Balbinot, E.,
& Esselink, A. F. (2023). Hidden deep in the halo:
selection of a reduced proper motion halo catalogue and mining
retrograde streams in the velocity space. Monthly
Notices of the Royal Astronomical Society,
521(2), 2087-2102. https://doi.org/10.1093/mnras/stad380
2022
Borre,
C. C., Aguirre Børsen-Koch, V., Helmi, A.,
Koppelman, H. H., Nielsen, M. B., Rørsted, J. L.,
Stello, D., Stokholm, A., Winther, M. L., Davies, G. R., Hon, M.,
Kruijssen, J. M. D., Laporte, C. F. P., Reyes, C., & Yu, J.
(2022). Age determination of galaxy merger remnant stars
using asteroseismology. Monthly Notices of the
Royal Astronomical Society, 514(2), 2527-2544.
https://doi.org/10.1093/mnras/stac1498
Reino,
S., Rossi, E. M., Sanderson, R. E., Sellentin, E., Helmi,
A., Koppelman, H. H., & Sharma, S. (2022).
Erratum: Galactic potential constraints from clustering in
action space of combined stellar stream data.
Monthly Notices of the Royal Astronomical
Society, 512, 4455-4463. https://doi.org/10.1093/mnras/stac694
Gaia
Collaboration, Klioner, S. A., Lindegren, L., Mignard, F.,
Hernández, J., Ramos-Lerate, M., Bastian, U., Biermann, M.,
Bombrun, A., de Torres, A., Gerlach, E., Geyer, R., Hilger, T.,
Hobbs, D., Lammers, U. L., McMillan, P. J., Steidelmüller, H.,
Teyssier, D., Raiteri, C. M., ... Zhao, H. (2022). Gaia Early
Data Release 3. The celestial reference frame (Gaia-CRF3).
Astronomy & Astrophysics, 667,
Article A148. https://doi.org/10.1051/0004-6361/202243483
Matsuno,
T., Koppelman, H. H., Helmi, A.,
Aoki, W., Ishigaki, M. N., Suda, T., Yuan, Z., & Hattori, K.
(2022). High-precision chemical abundances of Galactic
building blocks: The distinct chemical abundance sequence of
Sequoia. Astronomy & Astrophysics,
661, Article A103. https://doi.org/10.1051/0004-6361/202142752
Matsuno,
T., Dodd, E., Koppelman, H.
H., Helmi, A., Ishigaki, M. N., Aoki, W., Zhao,
J., Yuan, Z., & Hattori, K. (2022). High-precision
chemical abundances of Galactic building blocks: II. Revisiting the
chemical distinctness of the Helmi streams.
Astronomy & Astrophysics, 665,
Article A46. https://doi.org/10.1051/0004-6361/202243609
Lövdal,
S. S., Ruiz-Lara, T., Koppelman, H.
H., Matsuno, T., Dodd, E.,
& Helmi, A. (2022). Substructure in the stellar
halo near the Sun: I. Data-driven clustering in integrals-of-motion
space. Astronomy & Astrophysics,
665, Article A57. https://doi.org/10.1051/0004-6361/202243060
Ruiz-Lara,
T., Matsuno, T., Lövdal, S.
S., Helmi, A., Dodd, E.,
& Koppelman, H. H. (2022). Substructure in the
stellar halo near the Sun. II. Characterisation of independent
structures. Astronomy &
Astrophysics, 665, Article A58. https://doi.org/10.1051/0004-6361/202243061
Dodd,
E., Helmi, A., & Koppelman, H.
H. (2022). Substructures, resonances, and debris
streams: A new constraint on the inner shape of the Galactic dark
halo. Astronomy & Astrophysics,
659, Article A61. https://doi.org/10.1051/0004-6361/202141354
Ruiz-Lara,
T., Helmi, A., Gallart, C., Surot, F., &
Cassisi, S. (2022). Unveiling the past evolution of the
progenitor of the Helmi streams. Astronomy &
Astrophysics, 668, L10. https://doi.org/10.1051/0004-6361/202244127
2021
Gaia
Collaboration (2021). Corrigendum: Gaia Early Data Release 3.
Summary of the contents and survey properties.
Astronomy & Astrophysics, 650,
C3. https://doi.org/10.1051/0004-6361/202039657e
Koppelman,
H. H., & Helmi, A. (2021).
Determination of the escape velocity of the Milky Way using a
halo sample selected based on proper motion.
Astronomy & Astrophysics, 649,
Article A136. https://doi.org/10.1051/0004-6361/202038777
Koppelman,
H. H., Hagen, J. H. J., & Helmi,
A. (2021). Frequencies, chaos, and resonances: A study
of orbital parameters of nearby thick-disc and halo stars.
Astronomy & Astrophysics,
647(March 2021), Article A37. https://doi.org/10.1051/0004-6361/202039390
Gaia
Collaboration, Klioner, S. A., Mignard, F., Lindegren, L., Bastian,
U., McMillan, P. J., Hernández, J., Hobbs, D., Ramos-Lerate,
M., Biermann, M., Bombrun, A., de Torres, A., Gerlach, E., Geyer,
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