A group of astrophysicists has utilized the James Webb Space Telescope to identify three potential “dark stars,” speculated to be fueled by particles of dark matter. These theoretical celestial bodies surpass our sun in size and luminosity, offering a remarkable opportunity to enhance our comprehension of dark matter—a perplexing puzzle within the realm of physics. Moreover, the existence of these enigmatic stars could resolve the existing inconsistency between the prevailing cosmological model and the observation of early large galaxies in the universe.
Stars typically derive their radiance from the fusion process, where atoms merge and release energy, illuminating the darkness of space. However, what if there is an alternative method to power a star?
The James Webb Space Telescope (JWST) recently provided images that enabled a team of astrophysicists to detect three brilliant objects that might be classified as “dark stars.” These hypothetical entities are considerably larger and brighter than our sun, deriving their energy from the annihilation of dark matter particles. Confirming the presence of dark stars would not only be a captivating discovery on its own but also hold immense significance in shedding light on the nature of dark matter—an enduring enigma in the field of physics.
Originally categorized as galaxies by the JWST Advanced Deep Extragalactic Survey (JADES) in December 2022, these three objects (JADES-GS-z13-0, JADES-GS-z12-0, and JADES-GS-z11-0) are now contemplated as potential “dark stars.” The research, conducted by a team including Katherine Freese from The University of Texas at Austin, was published on July 11 in the Proceedings of the National Academy of Sciences.
While dark matter constitutes approximately 25% of the universe, its precise composition remains elusive. Scientists propose that it consists of a novel type of elementary particle, fueling a quest to detect such particles. Among the leading candidates are Weakly Interacting Massive Particles (WIMPs). When these particles collide, they self-annihilate, generating heat that influences collapsing hydrogen clouds, transforming them into radiant dark stars. Identifying supermassive dark stars could provide valuable insights into dark matter by studying their observable characteristics.
To ascertain the validity of these candidate objects as dark stars, further observations using JWST will analyze their spectroscopic properties, including variations in light intensity at specific frequencies.
Confirming the existence of dark stars may also aid in resolving a conundrum presented by the JWST observations: an apparent excess of large galaxies during the early stages of the universe, which contradicts the predictions of the standard cosmological model.
Freese, the director of the Weinberg Institute for Theoretical Physics and the Jeff and Gail Kodosky Endowed Chair in Physics at UT Austin, commented, “While proposing something entirely new, as we did, is always less probable, it is more likely that something within the standard model needs tuning. However, if some of these objects resembling early galaxies are indeed dark stars, the simulations of galaxy formation would align more closely with observations.”
These three potential dark stars, previously identified as galaxies, were initially discovered in December 2022 as part of the JWST Advanced Deep Extragalactic Survey (JADES). Spectroscopic analysis conducted by the JADES team confirmed that these objects were observed between approximately 320 million and 400 million years after the Big Bang, making them among the earliest celestial entities ever detected.
Freese stated, “When we examine the James Webb data, we encounter two competing possibilities regarding these objects. One suggests that they are galaxies housing millions of ordinary population-III stars, while the other hypothesis proposes that they are dark stars. Surprisingly, a single dark star emits sufficient light to rival an entire galaxy of stars.”
Theoretically, dark stars have the potential to grow several million times larger than our sun and emit brightness up to 10 billion times greater.
Ilie, an assistant professor of physics and astronomy at Colgate University, shared, “We predicted in 2012 that supermassive dark stars could be observed with JWST. As demonstrated in our recently published article, we have already identified three potential supermassive dark stars while analyzing JWST data for the four high-redshift JADES objects spectroscopically confirmed by Curtis-Lake et al. I am confident that we will soon discover many more.”
The concept of dark stars originated from discussions between Freese and Doug Spolyar, a former graduate student at the University of California, Santa Cruz. They pondered over the influence of dark matter on the first stars forming in the universe and subsequently sought the collaboration of Paolo Gondolo, an astrophysicist at the University of Utah. Following years of development, they published their initial research on this theory in the journal Physical Review Letters in 2008.
Together, Freese, Spolyar, and Gondolo devised a model that suggests dense clusters of dark matter coexist with hydrogen and helium gas at the cores of early protogalaxies. As the gas cools, it collapses and draws in dark matter particles. With increasing density, the annihilation of dark matter intensifies, generating additional heat that prevents the gas from collapsing into a core dense enough to support fusion, as seen in ordinary stars. Instead, it continues to accumulate gas and dark matter, expanding in size and radiance. In contrast to conventional stars, the power source of dark stars is distributed evenly rather than concentrated in the core. Given sufficient dark matter, these stars could grow to be several million times more massive than our sun and emit brightness up to 10 billion times greater.
This research received funding from the U.S. Department of Energy’s Office of High Energy Physics program and the Vetenskapsradet (Swedish Research Council) at the Oskar Klein Centre for Cosmoparticle Physics at Stockholm University.
Frequently Asked Questions (FAQs) about dark stars
What did the James Webb Space Telescope discover regarding “dark stars”?
The James Webb Space Telescope identified three potential “dark stars,” which are theoretical celestial objects larger and brighter than our sun, powered by dark matter particles.
How can dark stars contribute to our understanding of dark matter?
Confirming the existence of dark stars could provide valuable insights into the nature of dark matter, one of the significant unsolved mysteries in physics.
What could the discovery of dark stars reconcile?
The existence of dark stars could potentially reconcile the discrepancy between the current standard cosmology model and the observation of large galaxies in the early universe.
How do dark stars differ from ordinary stars?
Dark stars, powered by the annihilation of dark matter particles, can grow to be several million times the mass of our sun and emit brightness up to 10 billion times greater. Their power source is evenly spread out, rather than concentrated in the core like ordinary stars.
How were these potential dark stars initially identified?
Originally categorized as galaxies, these three potential dark stars (JADES-GS-z13-0, JADES-GS-z12-0, and JADES-GS-z11-0) were first detected by the JWST Advanced Deep Extragalactic Survey (JADES). Subsequent analysis revealed their potential as dark stars.
More about dark stars
- James Webb Space Telescope
- Proceedings of the National Academy of Sciences
- University of Texas at Austin – Weinberg Institute for Theoretical Physics
- Colgate University – Department of Physics and Astronomy
- Physical Review Letters