Posted on by Evan Gough

Astronomers Think They’ve Found Examples of the First Stars in the Universe

An artist's illustration of some of the Universe's first stars. Called Population 3 stars, they formed a few hundred million years after the Big Bang. Image Credit: By NASA/WMAP Science Team - https://www.nasa.gov/vision/universe/starsgalaxies/fuse_fossil_galaxies.html (image link), Public Domain, https://commons.wikimedia.org/w/index.php?curid=1582286

When the first stars in the Universe formed, the only material available was primordial hydrogen and helium from the Big Bang. Astronomers call these original stars Population Three stars, and they were extremely massive, luminous, and hot stars. They’re gone now, and in fact, their existence is hypothetical.

But if they did exist, they should’ve left their fingerprints on nearby gas, and astrophysicists are looking for it.

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Posted on by Evan Gough

The Large Magellanic Cloud isn’t Very Metal

This image shows the Large and Small Magellanic Clouds in the sky over the ESO's Paranal Observatory and the four telescopes of the VLT. Image Credit: By ESO/J. Colosimo - http://www.eso.org/public/images/potw1511a/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=38973313

The Large Magellanic Cloud (LMC) is the Milky Way’s most massive satellite galaxy. Because it’s so easily observed, astronomers have studied it intently. They’re interested in how star formation in the LMC might have been different than in the Milky Way.

A team of researchers zeroed in on the LMC’s most metal-deficient stars to find out how different.

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Posted on by Evan Gough

Even if We Can’t See the First Stars, We Could Detect Their Impact on the First Galaxies

Population III stars were the Universe's first stars. They were extremely massive, luminous stars, and many of them exploded as supernovae. How did they shape the early galaxies? Image Credit: DALL-E

For a long time, our understanding of the Universe’s first galaxies leaned heavily on theory. The light from that age only reached us after travelling for billions of years, and on the way, it was obscured and stretched into the infrared. Clues about the first galaxies are hidden in that messy light. Now that we have the James Webb Space Telescope and its powerful infrared capabilities, we’ve seen further into the past—and with more clarity—than ever before.

The JWST has imaged some of the very first galaxies, leading to a flood of new insights and challenging questions. But it can’t see individual stars.

How can astronomers detect their impact on the Universe’s first galaxies?

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Posted on by Evan Gough

Can Webb Find the First Stars in the Universe?

The Universe’s very first stars had an important job. They formed from the primordial elements created by the Big Bang, so they contained no metals. It was up to them to synthesize the first metals and spread them out into the nearby Universe.

The JWST has made some progress in finding the Universe’s earliest galaxies. Can it have the same success when searching for the first stars?

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