Eric Mamajek

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Eric E. Mamajek (born 1975) is an American astrophysicist. He is a principal scientist at the Jet Propulsion Laboratory (JPL) and the deputy program chief scientist for the NASA Exoplanet Exploration Program.

Mamajek's research interests have focused on the formation and evolution of stars, planets, substellar objects, and circumstellar disks, with an emphasis on characterizing stars' ages and membership in kinematic groups and multiple systems.

Mamajek was born in Pittsburgh, Pennsylvania, in 1975.[1] He graduated from Bethel Park High School in 1993[2] and completed his bachelor of science from Penn State University in 1998. Later in 2000, he earned a master of science in physics from the University of New South Wales. He later studied at the University of Arizona, where he received his master of science and Ph.D. in astronomy in 2001 and 2004, respectively.[3]

In 2008, Mamajek joined the University of Rochester as an assistant professor,[3] became associate professor in 2013 and professor in 2016. In 2016, he was appointed as deputy program chief scientist for NASA's Exoplanet Exploration Program at the JPL and was promoted to JPL principal scientist in the Astrophysics and Space Sciences directorate.[1]

Mamajek was the chair of the IAU Working Group on Star Names from 2016 to 2021.[4]

Mamajek's research has addressed the formation, evolution, and characterization of stars, substellar objects, and exoplanetary systems, especially in the solar neighborhood. He has worked on determining stellar ages, distances,[5] and kinematics of young stars and associations,[6] as well as protoplanetary disks around stars.[7] He has determined rotation periods,[8] X-ray luminosities, and studied the association between magnetically generated stellar rotation and coronal activity.[9]

Mamajek is the eponym of "Mamajek's Law" for the increasing discovery rate of exoplanets,[10][11] and is the co-discoverer of the ringed substellar object J1407b, which has sometimes been called "Mamajek's Object".[12] A focus of his research work lies in calibrating and applying age-dating techniques for stars[13] and young stellar groups.[14] Similarly, he has investigated young open clusters and stellar associations[15] and utilized Bayesian inference to calculate membership probability for 29 stellar associations within 150 parsecs of the Sun.[16] His work has also explored the Scholz's star's Sun encounter.[17] In collaboration with Stapelfeldt, he has documented the list of nearby stars which will be the best target stars for the future NASA Habitable Worlds Observatory to search for potentially habitable worlds.[18]

• Mamajek, Eric E.; Hillenbrand, Lynne A. (2008). "Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics". The Astrophysical Journal. 687 (2): 1264–1293. arXiv:0807.1686. Bibcode:2008ApJ...687.1264M. doi:10.1086/591785.
• Mamajek, Eric E.; Usuda, Tomonori; Tamura, Motohide; Ishii, Miki (2009). "Initial Conditions of Planet Formation: Lifetimes of Primordial Disks". AIP Conference Proceedings. 1158 (1): 3–10. arXiv:0906.5011. Bibcode:2009AIPC.1158....3M. doi:10.1063/1.3215910.
• Wright, Nicholas J.; Drake, Jeremy J.; Mamajek, Eric E.; Henry, Gregory W. (2011). "The Stellar-Activity-Rotation Relationship and The Evolution of Stellar Dynamos". The Astrophysical Journal. 743 (1): 48. arXiv:1109.4634. Bibcode:2011ApJ...743...48W. doi:10.1088/0004-637X/743/1/48.
• Pecaut, Mark J.; Mamajek, Eric E. (2013). "Intrinsic Colors, Temperatures, And Bolometric Corrections of Pre-Main-Sequence Stars". The Astrophysical Journal Supplement Series. 208 (1): 9. arXiv:1307.2657. Bibcode:2013ApJS..208....9P. doi:10.1088/0067-0049/208/1/9.
• Gagné, Jonathan; Mamajek, Eric E.; Malo, Lison; Riedel, Adric; Rodriguez, David; et al. (2018). "BANYAN. XI. The BANYAN Σ Multivariate Bayesian Algorithm to Identify Members of Young Associations with 150 pc". The Astrophysical Journal. 856 (1): 23. arXiv:1801.09051. Bibcode:2018ApJ...856...23G. doi:10.3847/1538-4357/aaae09.
• Mamajek, Eric; Stapelfeldt, Karl (2024). "NASA Exoplanet Exploration Program (ExEP) Mission Star List for the Habitable Worlds Observatory (2023)". arXiv:2402.12414 [astro-ph.IM].