Twelve million light years away, the Cigar Galaxy (M82) is in the throes of an extreme stellar baby boom, forging new stars at a rate ten times faster than our own Milky Way. The James Webb Space Telescope has now pierced its dusty veil to count an astonishing 16.5 million individual stars, offering an unprecedented census of this inferno.
Webb's infrared eyes sliced through the thick gas and dust that usually obscure M82's core, revealing a dense cluster of young, massive stars. The telescope resolved the galaxy's innermost workings, where intense radiation and powerful winds from newborn stars sculpt the surrounding material into colossal outflows. This detailed star-by-star count provides a benchmark for models of runaway star formation.
The Cigar Galaxy's furious pace cannot last—its fuel reserves are being consumed at a breakneck speed. Astronomers suspect the frenzy was triggered by a close gravitational encounter with its larger neighbor, M81, roughly 200 million years ago, which compressed gas clouds and sparked the current starburst.
This finding deepens understanding of how starburst galaxies evolve and expire. M82 serves as a nearby laboratory for processes that were common in the early universe, when galaxies churned out stars far more rapidly than today. Webb's resolution allows scientists to test theories about the role of galactic interactions in driving such episodes.
A lingering question remains whether similar star-by-star censuses are feasible for more distant starburst galaxies, given Webb's sensitivity limits. The current count covers only a fraction of M82's full stellar population, leaving room for surprises deeper within its dusty core.