MIT EAPS Directory

Benjamin Rackham

51 Pegasi b Postdoctoral Fellow

Research Description

Research Statement: Ben works on the detection and characterization of transiting exoplanets. He is interested primarily in small exoplanets around nearby small stars that afford the best opportunities for detailed atmospheric characterization, including searches for biosignatures with near-future telescopes. Starspots can mimic or mask atmospheric features in transmission spectra, and so Ben's current work focuses on developing new approaches for constraining stellar photospheric heterogeneity and disentangling stellar and planetary signals in transmission spectra.


Rackham, B. V., Apai, D., & Giampapa, M. S. 2019. The Transit Light Source Effect II: The Impact of Stellar Heterogeneity on Transmission Spectra of Planets Orbiting Broadly Sun-like Stars. AJ 157, 96.

Rackham, B. V., Apai, D., & Giampapa, M. S. 2018. The Transit Light Source Effect: False Spectral Features and Incorrect Densities for M-dwarf Transiting Planets. ApJ 853, 122.

Rackham, B. V., Espinoza, N., Apai, D., et al. 2017. ACCESS I: An Optical Transmission Spectrum of GJ 1214b Reveals a Heterogeneous Stellar Photosphere. ApJ 834, 151.

Bixel, A., Rackham, B. V., Apai, D., et al. 2019. ACCESS: Ground-based Optical Transmission Spectroscopy of the Hot Jupiter WASP-4b. AJ 157, 68.

Espinoza, N., Rackham, B. V., Jordán, A. et al. 2019. ACCESS: A Featureless Optical Transmission Spectrum for WASP-19b from Magellan/IMACS. MNRAS 482, 2065.

Pinhas, A., Rackham, B. V, Madhusudhan, N., & Apai, D. 2018. Retrieval of planetary and stellar properties in transmission spectroscopy with AURA. MNRAS 480, 5314.

Niraula, P., de Wit, J., Rackham, B. V., et al. 2020. π Earth: a 3.14-day Earth-sized Planet from K2’s Kitchen served warm by the SPECULOOS Team. AJ, in press. 

Gibbs, A., Bixel, A., Rackham, B. V., et al. 2020. EDEN: Sensitivity Analysis and Transiting Planet Detection Limits for Nearby Late Red Dwarfs. AJ 159, 169.

Zhang, Z., Zhou, Y., Rackham, B. V., & Apai, D. 2018. The Near-Infrared Transmission Spectra of the TRAPPIST-1 Planets b, c, d, e, f, and g and Stellar Contamination in Multi-Epoch Transit Spectra. AJ 156, 178.

Contact Information




PhD in Astronomy & Astrophysics, 2018