Dr. Sarah Pearson

Astrophysicist, Science Communicator & Public Speaker

-PhD commencement 2018, Columbia

Academic career

Sarah has published more than 10 scientific papers [ADS link] in several journals, including Nature Astronomy. Her science covers a broad range of topics such as galactic collisions, stellar streams, stellar explosions and dark matter. Her publications have been cited ~200 times, and she has given invited talks at Harvard, MIT, the Institute for Advanced Study, Princeton and several other high profile institutions. Additionally, she has also won awards for her research one of which was the Danish Women in Physics Prize.


Sarah obtained her Bachelor’s degree in Physics from the University of Copenhagen in 2012, after which she acquired her Master’s and PhD degrees in Astronomy from Columbia University in 2015 and 2018, respectively. Currently, she holds a Postdoctoral Research Fellowship at the Flatiron Institute’s Center for Computational Astrophysics in New York City, where she studies galactic dynamics, dark matter and the Galactic bar.

Research interests

Stellar streams
During her PhD, Sarah worked on several projects related to tidal streams emerging from disrupting clusters of stars. In particular, she showed that the shape of the dark matter mass distribution in the Milky Way can be distinguished based on the morphology of stellar streams. Streams spread much further in space on mildly chaotic orbits. Sarah dubbed this mechanism stream-fanning in her Pearson et al. 2015 article in the Astrophysical Journal. In Pearson et al. 2019, Sarah and her collaborators recently demonstrated that thin stellar streams from globular cluster will be observable in at least 200 nearby galaxies with NASA's WFIRST.

Colliding galaxies
Sarah has been involved in observational (Pearson et al. 2016, Privon et al. 2017) and theoretical (Pearson et al. 2018, Besla et al. 2018) studies on the nature of collisions between dwarf galaxies. The motivation for investigating this population of galaxies, is to better understand how galaxies build up their mass in the early Universe, and how they cycle through their matter today.

The Galactic Bar
During the last year of her PhD and throughout her postdoc, Sarah has become interested in galactic bars. In her Pearson et al. 2017 publication in Nature Astronomy, she showed that bars can punch holes in stellar streams. The signature of those events, is similar to the signature predicted from dark matter subhalos passing close by stellar streams. She is now working on several projects related to understanding the formation and evolution of galactic bars.

Scientific journal articles

First & second author [ADS link]

14. Variations in the width, density, and direction of the Palomar 5 tidal tails
Bonaca, A., Pearson, S., Price-Whelan, A. et al., 2019, submitted to AAS journals, arXiv: 1910.00592

13. Detecting Thin Stellar Streams in External Galaxies: Resolved Stars & Integrated Light
Pearson, S., Starkenburg, T., Johnston, K. V., Williams., B., and Ibata., R. , 2019, accepted to ApJ, arXiv: 1906.03264

12. Modeling the Baryon Cycle in Dwarf Galaxy Encounters: the Case of NGC4490 & NGC4485
Pearson, S., Privon, G., Besla, G., Putman, M. E., Martinez-Delgado, D., Johnston, K. V., Gabany, J. R., Patton, D. R., Kallivayalil, N. 2018, MNRAS, 480, 3069, arXiv: 1807.03791

11. Gaps and Length Asymmetry in the Stellar Stream Palomar 5 as Eects of Galactic Bar Rotation
Pearson, S., Price-Whelan, A. M., Johnston, K. V. 2017, Nature Astronomy, 1, 9 arXiv: 1703.04627

10. Local Volume TiNy Titans: Gaseous Dwarf-Dwarf Interactions in the Local Universe
Pearson, S., Besla, G., Putman, M. E., Lutz, K., Fernandez, X., Stierwalt, S., Patton, D. R. et al. 2016, MNRAS, 459, 1827, arXiv: 1603.09342

9. Tidal Stream Morphology as an Indicator of Dark Matter Halo Geometry: the Case of Palomar 5
Pearson, S., Kupper, A. H. W., Johnston, K. V., A. M. Price-Whelan, 2015, ApJ, 799, 1, arXiv: 1410.3477

8. Unraveling the Origin of Overionized Plasma in the Galactic Supernova Remnant W49B
Lopez, L. A., Pearson, S., Ramirez-Ruiz, E., Castro, D., Yamaguchi, H., Slane, P., Smith, R. 2013, ApJ, 764, 50, arXiv: 1309.1464

Other journal articles

7. Strong Effects of Weak Chaos: Chaotic Dispersal in the Galactic Potential
Yavetz, T., Johnston, K. V., Pearson, S., Price-Whelan, A., Weinberg, M., submitted to MNRAS, manuscript available upon request

6. Kinematics of the Palomar 5 stellar stream from RR Lyrae stars
Price-Whelan, A., Mateu, C., Iorio, G., Pearson, S., Bonaca, A., Belokurov, V., 2019, AJ, 158, 223, arXiv: 1910.00595

5. The Frequency of Dwarf Galaxy Multiples at Low Redshift in SDSS vs. Cosmological Expectations
Besla, G., Patton, D. R., Stierwalt, S., Rodriguez-Gomez, V., Patel, E., Kallivayalil, N. J., Johnson, K. E., Pearson, S., Privon, G. C.; Putman, M. E., 2018, MNRAS, 480, 3376, arXiv: 1807.06673

4. A Widespread, Clumpy Starburst in the Ongoing Isolated Dwarf Galaxy Merger DM1647+21
Privon, G., Stierwalt, S., Patton, D. R., Besla, G., Pearson, S., Putman, M., Johnson, K. E., Kallivayalil, N., Liss, S., 2017, ApJ, 846, 74, arXiv: 1708.02587

3. Evidence of Fanning in the Ophiuchus Stream
Sesar, B., Price-Whelan, A. M., Cohen, J. G., Rix, H. W., Pearson, S., Johnston, K. V., Bernard, E. J., Ferguson, A. M. N., Martin, N. F., Slater, C. T., Chambers, K. C., Flewelling, H., Wainscoat, R. J., Waters, C., 2016, ApJL, 816, 1, L4, arXiv: 1512.00469

2. Chaotic Dispersal of Tidal Debris
Price-Whelan, A., Johnston, K. V., Valluri, M., Pearson, S, Küpper, A. H. W., Hogg, D. W., 2016, MNRAS, 455, 1079, arXiv: 1507.08662

1. The Galactic Supernova Remnant W49B Likely Originates from a Jet-Driven Core-Collapse Explosion
Lopez, L. A., Ramirez-Ruiz, E., Castro, D., Pearson, S. 2013, ApJ, arXiv: 1301.0618