Maunakea Telescope Maps Cosmic Galaxy Collision

UH Hilo astronomer uses CFHT data to simulate 600 million years of galactic interaction.

Apr. 1, 2026 at 10:30am

Got story updates? Submit your updates here. ›

An astronomer at the University of Hawaiʻi at Hilo is using data from the Canada-France-Hawaiʻi Telescope (CFHT) on Maunakea to help reconstruct a slow-motion cosmic collision between two spiral galaxies, NGC 2207 and IC 2163, that has been unfolding for hundreds of millions of years.

Why it matters

Understanding the dynamics of galaxy collisions is crucial for advancing our knowledge of galaxy evolution, including events that may have shaped the formation of our own Milky Way galaxy billions of years ago.

The details

The research team, led by UH Hilo professor R. Pierre Martin and PhD student Camille Poitras, used the SITELLE instrument on CFHT to capture detailed views of the interacting galaxies. They ran hundreds of simulations to map the movement of gas, star birth, supernovae, chemical changes, and structural transformations over more than 600 million years as the galaxies have slammed together, pulled apart, and gradually merged into a single system.

  • The galaxy interaction began about 440 million years ago.
  • The galaxies are expected to fully merge into a single system over time, with their original structures no longer recognizable.

The players

R. Pierre Martin

A professor of astronomy at the University of Hawaiʻi at Hilo and the principal investigator on this study.

Camille Poitras

A PhD student who was the lead author on the study, having started the work as an undergraduate.

Canada-France-Hawaiʻi Telescope (CFHT)

An astronomical observatory located on Maunakea in Hawaiʻi, which houses the SITELLE instrument used in this research.

NGC 2207 and IC 2163

The two interacting spiral galaxies that are the focus of this study.

Got photos? Submit your photos here. ›

What they’re saying

“Understanding what's happening during these collisions is fundamental to our knowledge of galaxy evolution in general. Our own galaxy, the Milky Way, has been through multiple interactions during its lifetime, with one of them having likely triggered the formation of our Sun, about 5 billion years ago.”

— R. Pierre Martin, Professor of astronomy, University of Hawaiʻi at Hilo

“Telescope and lab time have become a central pillar of UH Hilo's astronomy program. Even if you've never used a telescope before in your life, for the four years you have here, it's all about hands-on experience.”

— R. Pierre Martin, Professor of astronomy, University of Hawaiʻi at Hilo

What’s next

The study shows how these galactic encounters can reshape galaxies by mixing elements, triggering new star formation, and influencing the emergence of planetary systems. Further research will continue to shed light on the complex dynamics of galaxy evolution.

The takeaway

This research demonstrates the value of hands-on, experiential learning in astronomy, with UH Hilo students gaining direct access to world-class observatories like CFHT to contribute to our understanding of the cosmos.