Radio telescopes help scientists map molecules in space and uncover where and how stars form

You may have heard the phrase "we are made of star-stuff." This statement by the astronomer Carl Sagan refers to the fact that elements heavier than hydrogen and helium were forged in the centers of the first stars. But how ...
As an astrochemist and radio astronomer, I study the places in the universe where stars are born as interstellar laboratories. I'm interested in how simple ingredients come together to form bigger and bigger molecules, including those that are building blocks of life. One way I do this is by mapping molecules in space and finding patterns between their abundance and the conditions around them.

Astronomers have mapped the distribution of molecules in interstellar space for several decades. From these maps, astronomers typically describe molecules' abundances, temperatures and how fast they're moving in each region.
Technology and techniques have improved over time, and now scientists are able to map these metrics at even more precise scales. My research team and I recently compared the findings from these newer methods with previous maps to make sure the earlier maps are consistent with our new maps.

A lab you can't visit

Stars form in molecular clouds: clumps of gas and dust that act as cosmic nurseries. These nurseries start out at extremely cold temperatures of about -442°F (-263°C). The material in them is also really spread out, with densities of about 100 molecules per cubic centimeter. By comparison, the air you are breathing right now has about 1019—or 10 quintillion—molecules per cubic centimeter.

ALMA, a powerful radio telescope in the Atacama Desert of Chile. Credit: J.F. Salgado (ESO), CC BY
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The Orion Nebula, captured in visible light by the Hubble Space Telescope. Credit: NASA, ESA, M. Robberto (Space Telescope Science Institute/ESA) and the Hubble Space Telescope Orion Treasury Project Team
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A map of one kind of heavy methanol in Orion KL derived from ALMA data. The contours show radio emission from dust particles in the nebula, and the color map shows methanol abundance as column density, or number of molecules over a two-dimensional area. A region called the Hot Core-Southwest has the highest abundance of methanol, indicated by the red region of the map. Wilkins et al. (2026)
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