How did primitive galaxies form? Astronomers are looking for light that holds an answer

Features of some of the oldest galaxies in the universe are in sharp focus.

Big picture: Data from telescopes in space and on Earth, including the new and powerful James Webb Space Telescope (JWST), will give astronomers a better picture of how the universe’s first stars and galaxies formed and evolved.

• A mysterious and critical moment in the universe several hundred million years after the Big Bang. During that period, E The first stars are born A gas made mostly of hydrogen and helium. These stars died and created heavier elements scattered throughout the universe, seeding the next generation of stars.
• A billion years after the Big Bang, the universe is full of supermassive galaxies and black holes. And so was the universe Ionizing Until then, change from a place filled with dark and dense primordial gas to a place where light can shine.
• Astronomers want to know what role the first stars and galaxies played in that crucial process—and how these early astronomical objects formed.

Inspirational Message: NASA released a stunning image this week showing thousands of galaxies — some of which formed within a billion years of the Big Bang — as part of the top five science images from JWST.

• The telescope is also designed to understand the evolution of the elements that formed the first galaxies.
• Jane Rigby, an astrophysicist at NASA’s Goddard Flight Center and operational program scientist for JWST, said, “This is how oxygen is formed in our bodies—in the stars, in the galaxies. We see this process beginning.

How it works: JWST views the universe in infrared (IR) light, giving astronomers access to distant stars and galaxies that would normally be obscured by cosmic dust.

• As the universe expands, optical light from primordial galaxies increases in wavelength and shifts to the infrared spectrum, moving through space and time. These galaxies are too faint to be seen with the naked eye, but can still be captured by lenses and detectors in sensitive telescopes.
• The JWST data will combine optical observations from the Hubble Space Telescope, the Atacama Large Millimeter/Submillimeter Array (ALMA) and Very Large Array (VLA), and radio data from the Chandra X-ray observatories and will give scientists an even more detailed view. the universe.

The big question: Combining this data, astronomers look for clues about how the first galaxies formed.

One Propose the theory Early Galaxies This created large clouds of gas and dust, which collapsed in on themselves, forming dense clouds that began to form galaxies.

• Another theory, supported by Smith’s data, suggests that small clumps of gas and dust coalesce to form large galaxies and clumps that are bound together by intense gravity.
• Overall guide He points out that galaxies are merging in a dominant way to grow, but observations are still sparse and the details unclear.

• “Galaxies are a chaotic process,” says Chris Carrelli, a radio astronomer at the National Science Foundation Observatory and a researcher on early galaxy formation.
• “[It’s] “Like weather,” cloud research is about identifying biophysical phenomena across galaxies, separating them from the details of a single galaxy, and understanding when and how the universe turned primordial gas into stars.

Between the lines: About 10 billion years ago, the mass of galaxies appears to have been controlled by gases, not stars. Data from ALMA. In new galaxies, the opposite is true.

• This molecular inventory provides clues about how galaxies – and their star-forming processes – have changed over time. Carrelli says that the amount of gas in galaxies has risen and fallen over the course of the universe’s history at the rate of star formation.

Where do you stand: Scientists were able to use JWST Analyze molecules — including oxygen, neon and hydrogen — formed one of the deep-field galaxies this week, just as it did 13.1 billion years ago.

• Spectra is the astronomical equivalent of a DNA sponge. Tweet on Twitter Jonathan McDowell is an astrophysicist at the Harvard-Smithsonian Center for Astrophysics. “What the Galaxies Did Symbolize in Their Light”.

What you expect: Comparing the properties of gas in nearby and distant galaxies will help astronomers study how the galactic medium has changed over time.

• “I think we’ll be able to better understand this evolution in the coming years, especially with JWST,” says Brian Trace, an astrophysicist and postdoctoral fellow at the Center for Astrophysics.