About Me

I'm a student from Indonesia currently studying astrophysics in Japan. My research focuses on galaxy evolution, with a particular interest in quiescent galaxies. I study them by analyzing the spatial distribution of their spectral energy distributions (SEDs). Outside of astrophysics, I enjoy traveling, music, and photography. Feel free to connect with me on Instagram: @novansaputra_!

Academic Timeline

  • MSc in Astrophysics at Astronomical Institute, Tohoku University, Japan (2024-present)
  • BSc in Astronomy at Institut Teknologi Bandung, Indonesia (2020-2024)
Me in Australian Parliament House, Canberra.

Research

Massive Quiescent Galaxies

Quiescent galaxies in the early universe provide crucial insights into how star formation shuts down and galaxies evolve structurally over time. Interestingly, massive quiescent galaxies at high redshift (~11 billion years ago) are much more compact than similar galaxies today, raising questions about their rapid formation and growth.

My research explores the physical origins of this compactness using spatially resolved SED fitting with piXedfit and deep JWST imaging. By analyzing the internal distributions of stellar mass and star formation, I investigate evolutionary scenarios such as inside-out quenching, minor mergers, and central compaction to understand how these dense early systems evolve into the extended quiescent galaxies seen in the present-day universe.

Massive quiescent galaxies in different times since Big Bang. Their size are significantly bigger in local universe compared to in early universe.

Publications

First Author

  • N. S. Haryana, M. Akiyama, Abdurro'uf, H. R. T. Wulandari, J. P. Alfonzo, K. Lee, N. Matsumoto, R. A. Sutanto, M. N. I. Effendi, I. K. Fitriana, I. N. Huda, A. T. Jaelani, S. H. Kusuma, L. Puspitarini, and D. P. Triani, 2025, "Stellar Mass Assembly History of Massive Quiescent Galaxies since z ~ 4: Insights from Spatially Resolved SED Fitting with JWST Data", submitted to ApJ.

Presentations

  • June 2025, IAU Symposium #396: Massive Galaxies across the Universe, Naples, Italy, "Stellar Mass Assembly History of Massive Quiescent Galaxies since z ~ 4: Insights from Spatially Resolved SED Fitting with JWST Data"
  • August 2024, 10th Galaxy Evolution Workshop, ASIAA, Taipei, Taiwan, "Study of Quiescent Galaxies in 2 < z < 7 using JWST and HST Data"
  • July 2024, Weekly Colloquia of RSAA ANU, Canberra, Australia, "Stochastic Star Formation Histories in Less Massive Quiescent Galaxies at High Redshift from Meraxes"
  • June 2024, ELT Science in Light of JWST, Tohoku University, Sendai, Japan, "Study of Quiescent Galaxies in 2 < z < 7 using JWST and HST Data"