Group Members

Amy Bonsor

Mariona Badenas-Augusti

Catriona McDonald

Xander Byrne

Yuqi Li

Richard Anslow

Laura Rogers

Current Master's students

Omri Nolan: Using the radial velocity technique to find planets around white dwarfs

Benjamin Richards: The mineralogy of dust debris around white dwarfs

Motoki (Tom) Yamano: Probing the composition of extrasolar material

Former PhD students

Andrew Buchan Thesis

Marc Brouwers Thesis

Laura Rogers Thesis

John Harrison The Chemical Diversity of Exo-planetary Systems derived from White Dwarf Pollution Thesis

Former Master's students

Morgan Liu: Numerical Simulations of Asteroid Formation via Gravitational Collapse

Pavan Tanna: Can we detect Moon-forming Impacts in other planetary systems?

David Irwine

Georgia Rawlins, It's all in the dust: infrared observations of white dwarfs

Hannah Sanderson, Gaia and Planets around White Dwarfs

Alfred Curry, Exoplanetary Systems and enrichment from short-lived radioactive nuclides

Joshua Lovell, 2017,Debris discs around giants

Krishan Sareen, 2016, Gaseous Emission Around White Dwarfs

Tom Callingham, 2016, The Circularisation of Sphaghettified Asteroids

John Harrison, 2015, The Chemical Diversity of Rocky Super-Earths

Research Interests

Two key questions:

1) How do planets form?

2) What are planets made from?

Composition is key to our understanding of the conditions on the surface of a planet, its interior and geology. The availability of the right building material is crucial, whilst the planet's formation history determines its current state. The origin of life on Earth and potentially elsewhere relies on the availability of the right materials, as well as the right geological conditions.

Planetary Systems Around White Dwarfs

The faint, compact remnants of stars like our Sun, white dwarfs, provide a unique opportunity to study the composition of exoplanetary material. The presence of metals from asteroids or comets show up in the spectra of the otherwise pure hydrogen or helium atmospheres. Bulk abundances can be determined for elements detected, including Mg, Ca, Fe, Ni, Cr, Al, Ti, C, O, N and many others. White dwarfs that have accreted planetary material provide unique insights into the composition, geology and loss of volatiles during planet formation.

Publications

Rogers L.~K., Bonsor A., Xu S., Buchan A.~M., Dufour P., Klein B.~L., Hodgkin S., et al., 2024, Seven White Dwarfs with circumestellar gas discs II: tracing the composition of exoplaneta\ ry building blocks, MNRAS, 532, 3866 pdf

Buchan A.~M., Bonsor A., Rogers L.~K., Brouwers M.~G., Shorttle O., Tremblay P.-E., 2024, White Dwarf constraints on geological \ processes at the population level, MNRAS, 532, 2705 pdf

Kao M.~L., Hawkins K., Rogers L.~K., Bonsor A., Dunlap B.~H., Sanders J.~L., Montgomery M.~H., et al., 2024,Hunting for Polluted\ White Dwarfs and Other Treasures with Gaia XP Spectra and Unsupervised Machine Learning, ApJ, 970, 181 pdf press release\

Madurga Favieres C., Kissler-Patig M., Xu S., Bonsor A., 2024, A catalog of 554 white dwarfs showing infrared excess from Gaia ED\ R3 and CatWISE catalogsA\&A, 688, A168. pdf

Veras D., Mustill A.~J., Bonsor A., 2024,The evolution and delivery of rocky extra-solar materials to white dwarfs, RvMG, 90, 14\ 1 pdf

Casewell, S.~L. et al (inc Bonsor, A.), 2024, PHL 5038AB: Is the brown dwarf causing pollution of its white dwarf host star?, M\ NRAS, MNRAS, 530, 3302. pdf

Rogers L.~K., Bonsor A., Xu S., Dufour P., Klein B.~L., Buchan A., Hodgkin S., et al., 2024, Seven white dwarfs with circumstellar gas discs I: white dwarf parameters and accreted planetary abundances, MNRAS, 527, 6038 \ pdf

Li, Y., Bonsor, A., Shorttle, O., 2024, Post-main sequence thermal evolution of planetesimals, MNRAS, 527, 1014–1032. pdf

Rogers, L.~K., Debes, J., Anslow, R., Bonsor, A. et al 2024, WD 0141-675: a case study on how to follow-up astrometric planet candidates around white dwarfs, MNRA\ S 527, 977–990 pdf

Anslow, R.~J., Bonsor, A., Rimmer, P.~B.\ 2023.\ Can comets deliver prebiotic molecules to rocky exoplanets?.\ Proceedings of the Royal Society of London Series A 479 pdf

Bonsor, A., Wyatt, M.~C., Marino, S., Davidsson, B.~J.~R., Kral, Q., Thebault, P.\ 2023.\ Secondary gas in debris discs released following the decay of long-lived \ radioactive nuclides, catastrophic or resurfacing collisions, MNRAS 526, 3115–3129 pdf

Brouwers M.~G., Buchan A.~M., Bonsor A., Malamud U., Lynch E., Rogers L., Koester D., Asynchronous accretion can mimic diverse white dwarf pollutants II: water content, MNRAS, 519, 2663–2679, 2023, pdf

Brouwers, M.~G., Bonsor, A., Malamud, U., Asynchronous accretion can mimic diverse white dwarf pollutants I: core and mantle fragments, MNRAS,519, 2, 2646-2662, 2023 pdf

Brouwers, M., A matter of life and death: the formation and destruction of planetary systems, PhD Thesis pdf

Bonsor, A., Lictenberg, T., Drazdowska, J., Buchan, A., The early formation of exoplanetesimals, as revealed by white dwrafs, Nature Astronomy, in press pdf

Lovell, J., Wyatt, M.C., Kalap, P., Kennedy, G.M., Marino, S., Bonsor, A., Penoyre, Z., Fulton, B.J., Pawellek, N., High-resolution ALMA and HST imaging of Kappa Cr B: a broad debris disc around a post-main-sequence star with low mass companions, 2022, MNRAS, 517, 2546 pdf

Sanderson, H., Bonsor, A., Mustill, A., Can Gaia find planets around white dwarfs?, 2022, MNRAS, 517, 5835 pdf

Curry, A., Bonsor, A., Lichtenberg, T., Shorttle, O., Prevalence of short-lived radioacitve isotopes across exoplanetary systems inferred from polluted white dwarfs, MNRAS, 515, 395 pdf

Buchan, A., Bonsor, A., Shorrtle, O., Wade, J., Harrison, J., Noack, L., Koester, D., Planets or asteroids? A geochemical method to constrain the masses of White Dwarf pollutants, 2022, MNRAS,510, 3512 pdf

Brouwers, M. G., Bonsor, A., Malamud, U. A road-map to white dwarf pollution: tidal disruption, eccentric grind-down and dust accretion, 2022, MNRAS, 509, 2404 pdf

Kral, Q., Pringle, J.E., Guilber-Lepoutre, A.,Matra, L., Moses, J.I., Lellouch, E., Wyatt, M.C., Biver, N., Bockelee-Morvan, D., Bonsor, A., Le Petit, F., Randall Gladstone, G., A molecular wind blows out of the Kuiper belt, 2021, A&A, 653, 14 pdf

Xu, S., Bonsor, A., Exogeneology from White Dwarfs, Elements, pdf

Brouwers, M. G., Ormel, C. W., Bonsor, A., Vazan, A., How planets grow by pebble accretion IV: Envelope opacity trends from sedimenting dust and pebbles, A&A, in press pdf

Lai, Samuel, Dennihy, Erik, Xu, Siyi, Nitta, Atsuko, Kleinman, Scot, Leggett, S. K., Bonsor, Amy, Hodgkin, Simon, Rebassa-Mansergas, Alberto, Rogers, Laura K., Infrared Excesses around Bright White Dwarfs from Gaia and unWISE. II, ApJ in press pdf

Absil, O., Marion, L., Ertel, S., Defrère, D., Kennedy, G. M., Romagnolo, A., Le Bouquin, J. -B., Christiaens, V., Milli, J., Bonsor, A., Olofsson, J., Su, K. Y. L., Augereau, J. -C., A near-infrared interferometric survey of debris-disk stars. VII. The hot-to-warm dust connection, A&A, 651, 29 pdf

Harrison, J.H.D., Bonsor, A.,Kama, M., Buchan, A., Blouin, S., Bayesian constraints on the origin and geology of exo-planetary material using a population of externally polluted white dwarfs, MN RAS, 504, 2853pdf Supplementary Information One

Bonsor, A., Jofré, P, Shorttle, O., Rogers, L. K., Xu, S., Melis, C., Host-star and exoplanet compositions: a pilot study using a wide binary with a polluted white dwarf, 2021, MNRAS, 503,1877 pdf

Harrison, J., Shorttle, O., Bonsor, A., Evidence for Post-nebula Volatisation in an Exoplanetary Body, 2020, EPSL, 554, 116694 pdf

Dennihy, Erik, Xu, Siyi, Lai, Samuel, Bonsor, Amy , Clemens, J.~C., Dufour, Patrick et al,, Five New Post-Main-Sequence Debris Disks with Gaseous Emission, ApJ, 905, 16 pdf

Harrison, J.H.D, Polluted White Dwarfs: Insights into Ancient Extrasolar Planetary Systems, PhD Thesis pdf

Rogers, Laura K., Xu, Siyi, Bonsor, Amy , Hodgkin, Simon, Su, Kate Y. L., von Hippel, Ted, Jura, Michael, Near-infrared variability in dusty white dwarfs: tracing the accretion of planetary material, MNRAS, 494,2, 2861 pdf

Amy Bonsor, Philip J Carter, Mark Hollands, Boris T Gansicke, Zoe Leinhardt, John HD Harrison, Are Exoplanetesimals differentiated?, MNRAS, 492,2, 2683pdf

Dorn, C., Harrison, J.H.D., Bonsor, Amy , Hands ,T.O., A new class of Super-Earths formed from high-temperature condensates: HD219134 b, 55 Cnc e, WASP-47 e, MNRAS, 484, 712, pdf

Xu, S., Su, K. Y.L., Rogers, Bonsor, A. , Olofsson, J., Veras, D., van Lieshout, R., Infrared Variability of Two Dusty White Dwarfs, 2018, ApJ, 866 (2) 108pdf

Bonsor, A. , Wyatt, M.C., Kral, Q., Kennedy, G., Shannon, A., Ertel, S., Using warm dust to constrain unseen planets, 2018, MNRAS, 480 (4) 5560-5579pd

Farihi, J., van Leishout, R., Cauley, P.W., Dennohy, E., Su, K.Y.L,, Kenyon, S.J., G Wilson, O Toloza, BT Gänsicke, T von Hippel, S Redfield, JH Debes, S Xu, L Rogers, A Bonsor , A Swan, AF Pala, WT Reach, Dust production and depletion in evolved planetary systems, 2018, MNRAS, 481 (2) 2601-2611pd

Harrison, J., Bonsor, A., Madhusudhan, N. Polluted White Dwarfs: Constraints on the Origin and Geology of Exoplanetary Material, 2018, MNRAS, 479 (3) 3814-3841 pdf

Marino, S. , Bonsor, A., Wyatt, M.C., Kral, Q. Scattering of exocoments by a planet chain: exozodi levels and the delivery of cometary material to inner planets, 2018, MNRAS, 479,1651-1671 pdf

Wyatt, M. C., Bonsor, A., Jackson, A. P., Marino, S., Shannon, A. How to design a planetary system for different scattering outcomes: giant impact sweet spot, maximizing exocomets, scattered discs, MNRAS, 464, 3385 pdf

Xu, S., Bonsor, A., White Dwarf Planetary Systems: insights regarding the fate of planetary systems pdf

Bonsor, A. , Farihi, J., Wyatt, M. C., Van Lieshout, R., Infrared observations of white dwarfs and the implications for the accretion of dusty planetary material, MNRAS, 468, 154 pdf

Marino, S., Wyatt, M. C., Panic, O., Matra, L., Kennedy, G. M., Bonsor, A., Kral, Q., Dent, W. R. F, Duchene, G., Wilner, D., ALMA observations of the $eta$ Corvi debris disc: inward scattering of CO-rich exocomets by a chain of 3-30 Mearth planets?, MNRAS, accepted pdf

Shannon, A., Bonsor, A., Kral, Q., Matthews, E., The unseen planets of double belt debris disk systems, MNRAS, 2016, 462, 116 pdf

Bonsor, A., Veras, D., A wide binary trigger for white dwarf pollution, MNRAS, 2015, 454, 53 pdf

June 2014 - June 2015 Maternity Leave

Veras, D., Leinhardt, Z. M., Bonsor, A., Gaensicke, B. T., Formation of planetary debris discs around white dwarfs - I. Tidal disruption of an extremely eccentric asteroid, MNRAS, 2014, 445, 2224 pdf

Farihi,J., Wyatt,M.C., Greaves,J.S., Bonsor, A., Sibthorpe, B., Panic, O., ALMA and Herschel observations of the prototype dusty and polluted white dwarf G29-38, MNRAS,2014,444, 1821 pdf

Bonsor, A., Leinhardt, Z. M., Carter, P.J., Elliot, T., Walter, M.J., Stewart, S. T., A Collisional Origin to Earth's Non-chondritic Composition?, Icarus,2014, 247, 291 pdf

Ertel,S., Absil,O., Defrere,D., Le Bouquin, J.-B ., Augereau, J.-C., Marion,L., Blind,N., Bonsor, A., Bryden, G., Lebreton, J., Milli, J.,A near-infrared interferometric survey of debris-disk stars. IV. An unbiased sample of 92 southern stars observed in H band with VLTI/PIONIER, A&A, 2014, 570, 128 pdf

Raymond, S., Bonsor, A., Vega's hot dust from icy planetesimals scattered inward by an outward-migrating planetary system, MNRAS, 2014, 444, 18 pdf

Bonsor, A., Raymond, S., Augereau, J.-C., Ormel, C., Planetesimal driven migration as an explanation for observations of high levels of warm, exozodiacal dust, MNRAS, 2014, 441, 2380 pdf

Jackson, A. P., Wyatt, M. C., Bonsor, A. & Veras, D., Debris froms giant impacts between planetary embryos at large orbital radi, MNRAS, 2014, 440, 3757-3777 pdf

Faramaz, V., Beust, H., Thebault, P., Augereau, J.-C., Bonsor, A., del Burgo, C., Ertel, S., Marshall, J. P., Milli, J., Montesinos, B., Mora, A., Bryden, G., Danchi, W., Eiroa, C., White, G. J . & Wolf, S., Can eccentric debris disks be long-lived?. A first numerical investigation and application to zeta2 Reticuli, A&A, 2014, 563, A72 pdf

Bonsor, A., Kennedy, G. M., Wyatt, M. C., Johnson, J. A. & Sibthorpe, B., Herschel observations of debris discs orbiting planet-hosting subgiants, MNRAS, 2014, 437, 3288 pdf

Wyatt, M. C., Farihi, J., Pringle, J. E. & Bonsor, A., Stochastic accretion of planetesimals on to white dwarfs: constraints on the mass distribution of accreted material from atmospheric pollution, MNRAS, 2014, 439, 3371 pdf

Beust, H., Augereau, J.-C.,Bonsor, A., Graham, J. R., Kalas, P., Lebreton, J., Lagrange, A.-M., Ertel, S., Faramaz, V. & Thébault, P., An independent determination of Fomalhaut b's orbit and the dynamical effects on the outer dust belt, A&A, 2014, 561, A43 pdf

Bonsor, A., Raymond, S., Augereau, J.-C., The short-lived production of exozodiacal dust in the aftermath of a dynamical instability in planetary systems, MNRAS, 2013,433, 2938, pdf

Bonsor, A., Kennedy, G. Crepp, J., Johnson, J., Wyatt, M.C. and Sibthorpe, B, Spatially Resolved Images of Dust Belt(s) Around the Planet-hosting Subgiant Kappa CrB, MNRAS, 431, 3025-3035pdf

Veras, D., Mustill, A. J., Bonsor, A., Wyatt, M.C., Simulations of two-planet systems through all phases of stellar evolution: implications for the instability boundary and white dwarf pollution, MNRAS, 431,1686-1708, pdf

Su, K. Y. L., Rieke, G. H., Malhotra, R., Stapelfeldt, K. R., Hughes, M., Bonsor, A., Wilner, D. J., Balog, Z., Watson, D. M., Werner, M. W., Misselt, K. A., Asteroid belts in debris disk twins: Vega and Fomalhaut, ApJ, 763, 118 pdf

Bonsor, A., Augereau J.-C., & Thebault, P., 2012, Scattering of small bodies by planets: a potential origin for exozodiacal dust?, A&A, in press, pdf

THESIS Bonsor, Amy, October 2011, 'Post-main Sequence Evolution of Planetary Systems' pdf

Bonsor, A., Wyatt, M.C., 2011,'The scattering of small bodies in planetary systems: constraints on the possible orbits of cometary material.', MNRAS,420, 2990, pdf

Veras, Dimitri, Wyatt, Mark C., Mustill, Alexander J., Bonsor, Amy, Eldridge, John J.,'The great escape: how exoplanets and smaller bodies desert dying stars', MNRAS, 417, 104, pdf

Bonsor, A., Mustill, A. J., Wyatt, M.C., 2010, 'Dynamical effects of stellar mass loss on Kuiper-like belts.', MNRAS, 414, 930. pdf

Bonsor & Wyatt, 2010,'Post-main-sequence evolution of A star debris discs', MNRAS, 409, 1631. pdf

Code

Credit: NASA, ESA, STScI, and G. Bacon (STScI)

PyllutedWD

A code to interpret the abundances found from spectroscopic observations and analysis of polluted white dwarfs. The code finds the most likely explanation for the observed abundances in a Bayesian framework, based on relative sinking, depletion of volatiles and the formation of an iron core.

Repository

Details of the code can be found in Harrison, PhD Thesis, Harrison et al, 2019, Harrison et al, 2021, Buchan et al, 2021

News

September 2024, Welcome to Mariona!

July 2024, Summer punting

June 2024 Siyi Xu and Chris Manser visit the IoA

Congratulations to Andy Buchan on his Viva

Celebrating Marc Brouwer's Viva

17th November, 2022, Marc Brouwers giving a talk at the KITP Meeting, White Dwarfs from Physics to Astrophysics pdf

15th November, 2022, The early formation of exoplanetesimals as revealed by white dwarfs, Bonsor et al, 2022, published in Nature Astronomy. pdf

11th November, 2022, Asychronous accretion onto white dwarfs, Brouwers et al, 2022, published in MNRAS Paper I pdf Paper II pdf

Congratulations to Dr Rogers on receipt of her PhD

Tim Cunningham, University of Warwick, visits our group. Lots of interesting science discussions, X-rays detected from accreting white dwarfs and a bicyle ride.

For the Public

Here are a few resources for the public:

Jaspreet, Roller Skates and Planets

A story book for primary-school children aimed at inspiring the next generation of scientists; co-created as part of the Planet Story project with a group of 45 children, local artist Alina Loth and outreach facilitator, Matthew Botthwell.

IoA Open Evening Talks : 'Making the Earth' Video on YouTube

BAA Summer Webinar, July 2021: 'Planet-eating White Dwarfs' Vide on YouTube

Laura Roger: Science Festival, 2020:How to make a planet? Video

Andy Buchan's Famelab 3 minutes on 'What Planets are Made of?'Video

Contact

Amy Bonsor

abonsor 'at' ast.cam.ac.uk

Institute of Astronomy

University of Cambridge

Madingley Road

Cambridge, CB3 0HA

Elements

Text

This is bold and this is strong. This is italic and this is emphasized. This is superscript text and this is subscript text. This is underlined and this is code: for (;;) { ... }. Finally, this is a link.


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Preformatted

i = 0;

while (!deck.isInOrder()) {
    print 'Iteration ' + i;
    deck.shuffle();
    i++;
}

print 'It took ' + i + ' iterations to sort the deck.';

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  • Sagittis adipiscing.
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Alternate

  • Dolor pulvinar etiam.
  • Sagittis adipiscing.
  • Felis enim feugiat.

Ordered

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  2. Etiam vel felis viverra.
  3. Felis enim feugiat.
  4. Dolor pulvinar etiam.
  5. Etiam vel felis lorem.
  6. Felis enim et feugiat.

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Name Description Price
Item One Ante turpis integer aliquet porttitor. 29.99
Item Two Vis ac commodo adipiscing arcu aliquet. 19.99
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Item Five Ante turpis integer aliquet porttitor. 29.99
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Name Description Price
Item One Ante turpis integer aliquet porttitor. 29.99
Item Two Vis ac commodo adipiscing arcu aliquet. 19.99
Item Three Morbi faucibus arcu accumsan lorem. 29.99
Item Four Vitae integer tempus condimentum. 19.99
Item Five Ante turpis integer aliquet porttitor. 29.99
100.00

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