Helen Giles
About Me
Originally from a town in the North West of England, I was fascinated with astronomy from a young age.
After attending a summer space school for three years, I independently studied for a GCSE in Astronomy during the last four months of my final year of high school.
Two years later, I achieved the necessary grades to attend the University of St Andrews in Scotland to study Astrophysics.
​
In St Andrews, I opted to enter into the second year - taking each astronomy course possible.
During the course of my degree I undertook two summer internships in exoplanet atmospheres and detection, with Christiane Helling in St Andrews and Chas Beichman in Pasadena.
Then for my final year Masters project, studying starspot lifetimes from Kepler data, was supervised by Raphaëlle Haywood and Andrew Collier Cameron.
​
After earning an integrated Masters degree in Astrophysics (1st class with Honours), I secured a PhD position at the Observatoire de Genève in Switzerland where I continued my stellar activity work and further exoplanet discovery.
On June 26th 2019 I successfully defended my thesis 'Know thy Star, Know thy Planet - Disentangling Planet Discovery & Stellar Activity' which can be found here.
My Research
Starspots
Whilst we understand sunspots extremely well, our knowledge of these magnetic regions on other stars is limited. And given we can't resolve stellar surfaces to the same degree as we can observe the solar surface, we need to extrapolate information from another source.
​
During my Masters' project and PhD, I successfully determined the lifetimes of starspots from photometry obtained from the Kepler mission, and how they depend on the stellar spectral type in collaboration with Raphaëlle Haywood and Andrew Collier Cameron.
​
For details, see the paper available on arXiv.
Exoplanet Discovery & Characterisation
In my role as the CHEOPS PhD student, I conducted the exoplanet discovery and radial velocity follow-up of publicly released data from the K2 mission - in collaboration with Exoplanet groups around Europe, the USA and Chile. This resulted in three planet discoveries (one from a summer internship, two during my PhD).
​
For details, see the papers for Kepler-1654 b, K2-140 b and EPIC248847494b available on arXiv.
Publications
Total Publications: 19 | Total Refereed: 16 | First Author: 3 | h-index: 9
HD 213885b: A transiting 1-day-period super-Earth with an Earth-like composition around a bright (V = 7.9) star unveiled by TESS
Espinoza, N.; Brahm, R.; Henning, T.; Jordán, A.; Dorn, C.; Rojas, F.; Sarkis, P.; Kossakowski, D.; Schlecker, M.; DÃaz, M.R.; Jenkins, J.S.; Aguilera-Gomez, C.; Jenkins, J.M.; Twicken, J.D.; Collins, K.A.; Lissauer, J.; Armstrong, D.J.; Adibekyan, V.; Barrado, D.; Barros, S.C.C.; Battley, M.; Bayliss, D.; Bouchy, F.; Bryant, E.M.; Cooke, B.F.; Demangeon, O.D.S.; Dumusque, X.; Figueira, P.; Giles, H.; Lillo-Box, J.; Lovis, C.; Nielsen, L.D.; Pepe, F.; Pollacco, D.; Santos, N.C.; Sousa, S.G.; Udry, S.; Wheatley, P.J.; Turner, O.; Marmier, M.; Ségransan, D.; Ricker, G.; Latham, D.; Seager, S.; Winn, J.N.; Kielkopf, J.F.; Hart, R.; Wingham, G.; Jensen, E.L.N.; HeÅ‚miniak, K.G.; Tokovinin, A.; Briceño, C.; Ziegler, C.; Law, N.M.; Mann, A.W.; Daylan, T.; Doty, J.P.; Guerrero, N.; Boyd, P.; Crossfield, I.; Morris, R.L.; Henze, C.E.; Chacon, A.D.
​
Monthly Notices of the Royal Astronomical Society (pending, 2020)
Using HARPS-N to characterize the long-period planets in the PH-2 and Kepler-103 systems
Dubber, S.C.; Mortier, A.; Rice, K.; Nava, C.; Malavolta, L.; Giles, H.; Coffinet, A.; Charbonneau, D.; Vanderburg, A.; Bonomo, A.S.; Boschin, W.; Buchhave, L.A.; Collier Cameron, A.; Cosentino, R.; Dumusque, X.; Ghedina, A.; Harutyunyan, A.; Haywood, R.D.; Latham, D.; López-Morales, M.; Micela, G.; Molinari, E.; Pepe, F.A.; Phillips, D.; Piotto, G.; Poretti, E.; Sasselov, D.; Sozzetti, A.; Udry, S.
​
Monthly Notices of the Royal Astronomical Society, Volume 490:4, 5103-5121 (2019)
Exoplanet Imitators: A test of stellar activity behavior in radial velocity signals
Nava, C.; López-Morales, M.; Haywood, R.D.; Giles, H.A.C.
​
Submitted to Astrophysical Journal
Exoplanet characterisation in the longest known resonant chain: the K2-138 system seen by HARPS
Lopez, T. A.; Barros, S. C. C.; Santerne, A.; Deleuil, M.; Adibekyan, V.; Almenara, J. -M.; Armstrong, D. J.; Brugger, B.; Barrado, D.; Bayliss, D.; Boisse, I.; Bonomo, A. S.; Bouchy, F.; Brown, D. J. A.; Carli, E.; Demangeon, O.; Dumusque, X.; DÃaz, R. F.; Faria, J. P.; Figueira, P. Foxell, E.; Giles, H.; Hébrard, G.; Hojjatpanah, S.; Kirk, J.; Lillo-Box, J.; Lovis, C.; Mousis, O.; da Nóbrega, H. J.; Nielsen, L. D.; Neal, J. J.; Osborn, H. P.; Pepe, F.; Pollacco, D.; Santos, N. C.; Sousa, S. G.; Udry, S.; Vigan, A.; Wheatley, P. J.
​
Astronomy & Astrophysics, Volume 631, A90
Optical phase curve of the ultra-hot Jupiter WASP-121b
​Bourrier, V.; Kitzmann, D.; Kuntzer, T.; Nascimbeni, V.; Lendl, M.; Lavie, B.; Hoeijmakers, H. J.; Pino, L.; Ehrenreich, D.; Heng, K.; Allart, R.; Cegla, H. M; Dumusque, X.; Melo, C.; Astudillo-Defru, N.; Caldwell, D. A.; Cretignier, M.; Giles, H.; Henze, C. E.; Jenkins, J. Lovis, C.; Murgas, F.; Pepe, F.; Ricker, G. R.; Rose, M. E.; Seager, S.; Segransan, D.; Suarez-Mascareno, A.; Udry, S.; Vanderspek, R.; Wyttenbach, A.
​
Submitted to Astronomy & Astrophysics
PhD Thesis
Know thy Star, Know thy Planet - Disentangling Planet Discovery & Stellar Activity
Giles, H. A. C.
​
PhD Thesis, Université de Genève (2019)
The CORALIE survey for southern extrasolar planets. XVIII. Three new massive planets and two low-mass brown dwarfs at greater than 5 AU separation
Rickman, E. L.; Ségransan, D.; Marmier, M.; Udry, S.; Bouchy, F.; Lovis, C.; Mayor, M.; Pepe, F.; Queloz, D.; Santos, N. C.; Allart, R.; Bonvin, V.; Bratschi, P.; Cersullo, F.; Chazelas, B.; Choplin, A.; Conod, U.; Deline, A.; Delisle, J. -B.; Dos Santos, L. A. Figueira, P.; Giles, H. A. C.; Girard, M.; Lavie, B.; Martin, D.; Motalebi, F.; Nielsen, L. D.; Osborn, H.; Ottoni, G.; Raimbault, M.; Rey, J.; Roger, T.; Seidel, J. V.; Stalport, M.; Suárez Mascareño, A.; Triaud, A.; Turner, O.; Weber, L.; Wyttenbach, A.
​
Astronomy & Astrophysics, Volume 625, A71 (2019)
The solar benchmark: rotational modulation of the Sun reconstructed from archival sunspot records
Morris, B.M.; Davenport, J.R.A.; Giles, H.A.C.; Hebb, L.; Hawley, S.L.; Angus, R.; Gilman, P.A.; Agol, E.
​
Monthly Notices of the Royal Astronomical Society, Volume 484:3, 3244-3250 (2019)
A Jovian planet in an eccentric 11.5 day orbit around HD 1397 discovered by TESS
​Nielsen, L. D.; Bouchy, F.; Turner, O.; Giles, H.; Mascareño, A. Suárez; Lovis, C.; Marmier, M.; Pepe, F.; Ségransan, D.; Udry, S.; Otegi, J. F.; Ottoni, G.; Stalport, M.; Ricker, G.; Vanderspek, R.; Latham, D. W.; Seager, S.; Winn, J. N.; Jenkins, J. M.; Kane, S. R. Wittenmyer, R. A.; Bowler, B.; Crossfield, I.; Horner, J.; Kielkopf, J.; Morton, T.; Plavchan, P.; Tinney, C. G.; Zhang, Hui; Wright, D. J.; Mengel, M. W.; Clark, J. T.; Okumura, J.; Addison, B.; Caldwell, D. A.; Cartwright, S. M.; Collins, K. A.; Francis, J.; Guerrero, N.; Huang, C. X.; Matthews, E. C.; Pepper, J.; Rose, M.; Villaseñor, J.; Wohler, B.; Stassun, K.; Howell, S.; Ciardi, D.; Gonzales, E.; Matson, R.; Beichman, C.; Schlieder, J.
​
Astronomy & Astrophysics, Volume 623, A100 (2019)
Transiting planet candidate from K2 with the longest period
Giles H.A.C.; Osborn, H.P.; Blanco-Cuaresma, S.; Lovis, C.; Bayliss, D.; Eggenberger, P.; Collier Cameron, A.; Kristiansen, M.H.; Turner, O.; Bouchy, F.; Udry S.
​
Astronomy & Astrophysics, Volume 615, L13 (2018)
An Earth-sized exoplanet with a Mercury-like composition
Santerne, A.; Brugger, B.; Armstrong, D.J.; Adibekyan, V.; Lillo-Box, J.; Gosselin, H.; Aguichine, A.; Almenara, J.-M.; Barrado, D.; Barros, S.C.C.; Bayliss, D.; Boisse, I.; Bonomo, A.S.; Bouchy, F.; Brown, D.J.A.; Deleuil, M.; Delgado Mena, E.; Demangeon, O.; DÃaz, R.F.; Doyle, A.; Dumusque, X.; Faedi, F.; Faria, J. P.; Figueira, P.; Foxell, E.; Giles, H.A.C.; Hébrard, G.; Hojjatpanah, S.; Hobson, M.; Jackman, J.; King, G.; Kirk, J.; Lam, K.W.F.; Ligi, R.; Lovis, C.; Louden, T.; McCormac, J.; Mousis, O.; Neal, J.J.; Osborn, H.P.; Pepe, F.; Pollacco, D.; Santos, N.C.; Sousa, S.G.; Udry, S.; Vigan, A.
​
Nature Astronomy, Volume 2, 393-400 (2018)
An Accurate Mass Determination for Kepler-1655b, a Moderately Irradiated World with a Significant Volatile Envelope
Haywood, R.D.; Vanderburg, A.; Mortier, A.; Giles, H.A.C.; López-Morales, M.; Lopez, E.D.; Malavolta, L.; Charbonneau, D.; Collier Cameron, A.; Coughlin, J.L.; Dressing, C.D.; Nava, C.; Latham, D.W.; Dumusque, X.; Lovis, C.; Molinari, E.; Pepe, F.; Sozzetti, A.; Udry, S.; Bouchy, F.; Johnson, J.A.; Mayor, M.; Micela, G.; Phillips, D.; Piotto, G.; Rice, K.; Sasselov, D.; Ségransan, D.; Watson, C.; Affer, L.; Bonomo, A.S.; Buchhave, L.A.; Ciardi, D.R.; Fiorenzano, A.F.; Harutyunyan, A.
​
The Astronomical Journal, Volume 155, Issue 5, 203 (2018)
K2-140b - an eccentric 6.57 d transiting hot Jupiter in Virgo
Giles, H.A.C.; Bayliss, D.; Espinoza, N.; Brahm, R.; Blanco-Cuaresma, S.; Shporer, A.; Armstrong, D.; Lovis, C.; Udry, S.; Bouchy, F.; Marmier, M.; Jordán, A.; Bento, J.; Collier Cameron, A.; Sefako, R.; Cochran, W. D.; Rojas, F.; Rabus, M.; Jenkins, J.S.; Jones, M.; Pantoja, B.; Soto, M.; Jensen-Clem, R.; Duev, D.A.; Salama, M.; Riddle, R.; Baranec, C.; Law, N.M.
​
Monthly Notices of the Royal Astronomical Society, Volume 475:2, 1809-1818 (2018)
Validation and Initial Characterization of the Long-period Planet Kepler-1654 b
Beichman, C.A.; Giles, H.A.C.; Akeson, R.; Ciardi, D.; Christiansen, J.; Isaacson, H.; Marcy, G.M.; Sinukoff, E.; Greene, T.; Fortney, J.J.; Crossfield, I.; Hu, R.; Howard, A. W.; Petigura, E. A.; Knutson, H.A.
The Astronomical Journal, Volume 155, Issue 4, 158, 11, (2018)
Understanding Stellar Contamination in Exoplanet Transmission Spectra as an Essential Step in Small Planet Characterization
Apai, D.; Rackham, B.V.; Giampapa, M.S.; Angerhausen, D.; Teske, J.; Barstow, J.; Carone, L.; Cegla, H.; Domagal-Goldman, S.D.; Espinoza, N.; Giles, H.A.C.; Gully-Santiago, M.; Haywood, R.; Hu, R.; Jordan, A.; Kreidberg, L.; Line, M.; Llama, J.; López-Morales, M.; Marley, M.S.; de Wit, J.
​
White paper submitted to the NAS Committee on Exoplanet Science Strategy
A Kepler study of starspot lifetimes with respect to light-curve amplitude and spectral type
Giles, H.A.C.; Collier Cameron, A.; Haywood, R.D.
​
Monthly Notices of the Royal Astronomical Society, Volume 472:2, 1618-1627 (2017)
Ground-based photometry of the 21-day Neptune HD 106315c
Lendl, M.; Ehrenreich, D.; Turner, O. D.; Bayliss, D.; Blanco-Cuaresma, S.; Giles, H.; Bouchy, F.; Marmier, M.; Udry, S.
​
Astronomy & Astrophysics, Volume 603, L5 (2017)
Kepler-21b: A Rocky Planet Around a V = 8.25 Magnitude Star
López-Morales, M.; Haywood, R.D.; Coughlin, J.L.; Zeng, L.; Buchhave, L.A.; Giles, H.A.C.; Affer, L.; Bonomo, A.S.; Charbonneau, D.; Collier Cameron, A.; Consentino, R.; Dressing, C.D.; Dumusque, X.; Figueira, P.; Fiorenzano, A.F.M.; Harutyunyan, A.; Johnson, J.A.; Latham, D.W.; Lopez, E.D.; Lovis, C.; Malavolta, L.; Mayor, M.; Micela, G.; Molinari, E.; Mortier, A.; Motalebi, F.; Nascimbeni, V.; Pepe, F.; Phillips, D.F.; Piotto, G.; Pollacco, D.; Queloz, D.; Rice, K.; Sasselov, D.; Segransan, D.; Sozzetti, A.; Udry, S.; Vanderburg, A.; Watson, C.
​
The Astronomical Journal, Volume 152, Issue 6, 204 (2016)
Dust in brown dwarfs and extra-solar planets.
IV. Assessing TiO2 and SiO nucleation for cloud formation modelling
Lee, G.; Helling, Ch.; Giles, H.A.C.; Bromley, S.T.
​
Astronomy & Astrophysics, Volume 575, A11 (2015)
Talks & Posters
Contact Me
If you want to get in touch, I’d love to hear from you! You can either send me a message or find me on social media.