Skip to main content

James Webb researcher reveals how it will investigate the early universe

Once the James Webb Space Telescope begins science operations this summer, it will the world’s most powerful space telescope, and it will open new avenues for astronomy research. One of the researchers who will be working with James Webb, Massimo Stiavelli, the Webb Mission Office head at the Space Telescope Science Institute, has shared more information about how Webb will look back in time at some of the earliest stars and galaxies.

Because light takes time to travel, the further away from Earth we look, the earlier we are seeing in the development of the universe. Webb will be able to see more distant galaxies than ever before, allowing researchers to get a glimpse of the early stages of the universe. By looking at the composition of these very early stars and galaxies, researchers can get an idea of what was happening in the few minutes after the Big Bang.

Recommended Videos

“The chemical composition of the early universe, just after the big bang, is the product of the nuclear processes that took place in the first few minutes of the universe’s existence,” Stiavelli said, as shared in a NASA blog post. “These processes are known as ‘primordial nucleosynthesis.’ One of the predictions of this model is that the chemical composition of the early universe is largely hydrogen and helium. There were only traces of heavier elements, which formed later in stars. These predictions are compatible with observations, and are in fact one of the key pieces of evidence that support the hot big bang model.”

Webb will be searching out examples of these very old stars to see if they support current theories about the Big Bang. “The earliest stars formed out of material with this primordial composition,” Stiavelli said. “Finding these stars, commonly dubbed as the ‘First Stars’ or ‘Population III stars,’ is an important verification of our cosmological model, and it is within reach of the James Webb Space Telescope. Webb might not be able to detect individual stars from the beginning of the universe, but it can detect some of the first galaxies containing these stars.”

Stiavelli’s project is to look at one of the furthest galaxies discovered to date, called MACS1149-JD1, using Webb. The team will measure how much of the galaxy is made up of heavier elements, using an instrument called a spectrograph, so they can confirm whether it is made up of these very early stars. The project will be a part of Webb’s first year of science operations.

Georgina Torbet
Georgina has been the space writer at Digital Trends space writer for six years, covering human space exploration, planetary…
James Webb observes what happens when a planet is swallowed by a star
NASA’s James Webb Space Telescope’s observations of what is thought to be the first ever recorded planetary engulfment event revealed a hot accretion disk surrounding the star, with an expanding cloud of cooler dust enveloping the scene. Webb also revealed that the star did not swell to swallow the planet, but the planet’s orbit actually slowly decayed over time.

As planetary demises go, this one is pretty grisly: a planet falls closer and closer to its host star, getting hotter and hotter as it spirals inward, until it finally falls past the point of no return and is swallowed by the star in a tremendous flash of light. That's what happened in an event called ZTF SLRN-2020, and now the James Webb Space Telescope has been observing the aftermath to learn more about this rare event.

“Because this is such a novel event, we didn’t quite know what to expect when we decided to point this telescope in its direction,” said lead researcher Ryan Lau of NOIRLab, who used Webb's MIRI (Mid-Infrared Instrument) and NIRSpec (Near-Infrared Spectrograph) instruments to make observations. “With its high-resolution look in the infrared, we are learning valuable insights about the final fates of planetary systems, possibly including our own.”

Read more
James Webb captures a rare astronomical ring in the sky
This new NASA/ESA/CSA James Webb Space Telescope Picture of the Month features a rare cosmic phenomenon called an Einstein ring. What at first appears to be a single, strangely shaped galaxy is actually two galaxies that are separated by a large distance. The closer foreground galaxy sits at the center of the image, while the more distant background galaxy appears to be wrapped around the closer galaxy, forming a ring.

A striking new image from the James Webb Space Telescope shows a rare object called an Einstein ring. This shows what appears to be a ring-shaped object in the sky, but is actually created by two separate galaxies and the epic forces of gravity.

There's a useful astronomical phenomenon called gravitational lensing, in which a large object like a galaxy or a cluster of galaxies has so much mass that it actually bends spacetime. If a massive object sits in front of a more distant object, as seen from Earth, the massive object can act like a magnifying glass, letting us see the very distant object in more detail than would normally be possible. This is a relatively common finding in astronomical images, and is one way that scientists are able to study extremely distant galaxies.

Read more
James Webb captures gorgeous image of a Cosmic Tornado
The NASA/ESA/CSA James Webb Space Telescope observed Herbig-Haro 49/50, an outflow from a nearby still-forming star, in high-resolution near- and mid-infrared light with the NIRCam and MIRI instruments. The intricate features of the outflow, represented in reddish-orange color, provide detailed clues about how young stars form and how their jet activity affects the environment around them. A chance alignment in this direction of the sky provides a beautiful juxtaposition of this nearby Herbig-Haro object (located within our Milky Way) with a more distant, face-on spiral galaxy in the background.

The James Webb Space Telescope has captured another stunning image of space, this time showing the dramatic scenes around a baby star. Very young stars can throw off powerful jets of hot gas as they form, and when these jets collide with nearby dust and gas they form striking structures called Herbig-Haro objects.

This new image shows Herbig-Haro 49/50, located nearby to Earth at just 630 light-years away in the constellation Chamaeleon. Scientists have observed this object before, using the Spitzer Space Telescope, and they named the object the "Cosmic Tornado" because of its cone-like shape. To show the impressive powers of James Webb to capture objects like this one in exquisite detail, you can compare the Spitzer image from 2006 and the new James Webb image.

Read more