James Webb Space Telescope Finds Heavy Metals Surrounding the Milky Way’s Central Black Hole

New observations from the James Webb Space Telescope (JWST) have revealed a surprising concentration of heavy metals surrounding Sagittarius A*, the supermassive black hole at the center of the Milky Way. The discovery could provide new clues about how Earth acquired its heavy elements—and make it harder to solve one of the biggest mysteries surrounding local black holes.

What are “metals” in astronomy?

In astronomy, metals are elements heavier than hydrogen or helium. Common examples include oxygen, carbon, iron and gold. These elements are created through nuclear fusion inside stars nearing the end of their lives before being dispersed into space and incorporated into new generations of stars.

JWST detects metal-rich gas near Sagittarius A*

Scientists say the heavy elements detected by JWST likely came from a supernova—the explosion of a star that blasted metals into the region around Sagittarius A*.

The metals were detected as gas and appear to have a composition similar to that of some nearby stars. This suggests that the stars and gas may have originated at the same time. The researchers reported their observations in a paper published in the Astronomical Journal, following earlier work published in the Astrophysical Journal.

“We know that there is a black hole at the center of our galaxy, drawing in material, but we now know that it is eating far less material than other supermassive black holes,” said lead author Nicole Ford, a doctoral student in astrophysics at McGill University in Montreal.

“To understand why this is happening, we need to examine the properties of the materials that can be consumed, such as gas, dust, and the stars we orbit,” Ford said in a statement.

How JWST studied the galactic center

JWST orbits the Sun-Earth Lagrange point 2, about 1 million miles (1.5 million kilometers) from Earth in the opposite direction from the Sun. The telescope detected the thermal signature of clouds of gas swirling near Sagittarius A*, along with the metal content within those clouds.

The findings may improve scientists’ understanding of how metals are distributed around supermassive black holes in more distant galaxies. They may also help explain the processes that supply many of the elements found on Earth.

The presence of metals affects how quickly gas cools. That, in turn, influences how easily the gas can be drawn into a black hole, according to the McGill researchers.

Why the discovery complicates black hole research

Previous research published in the Astrophysical Journal showed that outgassing near a black hole is influenced by local cloud conditions. As a result, gas alone cannot be used as a reliable proxy for how often a black hole is active, the researchers said.

This makes the metal content and other properties of material near Sagittarius A* especially important for understanding why the Milky Way’s central black hole consumes relatively little matter compared with other supermassive black holes.

Study details

Ford, N.M., Balakrishnan, M., von Fehrenberg, S.D., Haggard, D., Michael, J.M., Cui, Y., Hora, J.L., Nielsen, J., Principe, G., Roychoudhury, T., Sabha, N.B., Smith, H.A., Sumners, Z. and Wilner, S.P. (2026). “Ionization structure and metal enrichment of the galactic center mini-spiral observed by JWST.” Astronomical Journal, 172(5), 267.

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Topics: James Webb Space Telescope, Milky Way, Sagittarius A*, black holes, astronomy