NASA’s James Webb Space Telescope Could Find Redshift Galaxies That Are the Oldest Objects in the Universe

After 25 years of development at a cost of nearly $10 billion, NASA’s James Webb Space Telescope finally debuted on Christmas day. Assuming there are no glitches and the six-ton ​​telescope can deploy its instruments to the full in the next 5.5 months, the qualified scientists will begin just the long arrays one after the other. Its 47 x 70 feet into whatever interests them.

Yoichi Tamura, a professor in the Department of Particles and Astrophysical Sciences at Nagoya University, Japan, knew what he would do with JWST when his turn came. “I will be looking for the reddest galaxies to identify the most distant ones,” Tamura told The Daily Beast.

Tamura and his Japanese, Dutch, and American teammates — who have scheduled observations with JWST at some point in the future — plan to point the telescope at a pair of suspected galaxies. suspected “redshift-13”. The team described potential galaxies and a strategy to survey them, in a new sheet of paper came online last month (though it’s yet to be peer-reviewed).

In astronomy, a “redshift” is a change in the infrared signature of a distant galaxy that helps us determine its age. As the object moves away from the observer, its light increases in wavelength and thus decreases in photon frequency and energy, causing that light to turn redder and redder.

The Redshift-13 galaxies lie at the outer edge of the known universe, meaning they were among the first obstacles facing outward as the universe began to expand after the Big Bang 13.8 billion years ago . No less than 13 billion years old, these galaxies are high-ranking citizens of the universe — and guardians of potentially profound secrets about the origins of, well, everything. Thousands of them can be seen from Earth, with the right technology.

Since astronomy is merely a glimpse of the light emitted by an object, we are literally looking at the object as it was before. A distance of 10 light years means that it takes 10 years for that light to get from point A to point B. So the image we get when we look at a high redshift galaxy is a subimage of the object. body. A long view of the Redshift-13 galaxy is a window into time, billions of years ago, when the universe was young.

Michał Michałowski, an astronomer at Adam Mickiewicz University in Poland, told The Daily Beast that very young galaxies contain very young stars, potentially showing us how those stars form. any. “This is an important topic because these early stars set the stage for the further evolution of galaxies by creating the first batch of heavy elements.”

The reddest and oldest galaxy astronomers have confirmed to date, GN-z11, has a redshift of 11, making it about 13.4 billion years old. “We hope to go further,” Tamura told The Daily Beast. (Recently controversial GN-z11, after a group of astronomers observed what they believe to be a gamma-ray burst from a distant galaxy and other groups attempted to make holes in that conclusion.)

Even with JWST at their disposal, Tamura and his teammates faced tough obstacles. Hunting for redshift-13 galaxies is a tricky business. “Early galaxies are predicted to be faint and rare according to the standard model of the universe,” explains Tamura.

In addition, nearby galaxies, other stars, or even derelict rockets – “astronomers”, as astronomers call them – tend to impede direct observation. That’s probably what happened to the purported gamma-ray burst from GN-z11.

But the biggest obstacle to observing these objects is hydrogen. Neutral hydrogen atoms can absorb a lot of the light emitted by a galaxy. They can alter the color of the galaxy and cloud its true redshift, thereby complicating an accurate assessment of its age and distance from Earth. A lot of hydrogen can accumulate in large spaces and disturb observations of distant objects. The hydrogen problem gets a lot worse when you look at a distant galaxy from within Earth’s hydrogen-rich atmosphere.

There is a solution — but an incomplete one. Using a sophisticated analytical method known as the “Lyman-break technique,” astronomers can work backwards from this hydrogen-modified color spectrum. Aaron Yung, a teammate of Tamura’s at NASA’s Goddard Space Flight Center in Maryland, told The Daily Beast: “We can get a rough estimate of its distance.

The Lyman-break method alone cannot accurately determine the redshift of the galaxy. Yung explains: “The distances estimated using this technique have quite a bit of uncertainty and are susceptible to contamination from objects in the foreground. Once astronomers have identified Feasibility redshift-13 galaxies by applying Lyman-break to existing surveys, they need to better telescopically — and preferably space-based — at the same target, ideally for several days at a time.

That’s where JWST comes in. This is the first of several newly deployed or developed space telescopes that, thanks to their larger and more sensitive arrays, have any chance of confirming that objects faint, reddish bodies that are ancient galaxies. In addition to JWST, these new telescopes include NASA’s Nancy Grace Roman Space Telescope, which could launch in the mid-2020s; as well as Japan’s GREX-PLUS, which is still more than a decade away.

Together, these three new telescopes can help astronomers identify and survey not only redshift-13 galaxies – but also older galaxies. Tamara and his colleagues think it might even be possible to detect one of the first galaxies ever to form, which astronomers predict will have a redshift of about 17.

The possibilities are almost too uncanny to conceive. A redshift-17 galaxy “must be very different from what we see in the nearby universe,” Tamura said. “It will contain very young star clusters, including even the first generation of stars.”

Those newborn stars can be massive – 10 times larger than the sun – and extremely hot and bright. They can also be short-lived and explosive. In the image of redshift galaxy-17, “the explosion waves from the supernova would run across the entire galaxy, causing the galaxy to become very violent,” explains Tamura.

Michałowski said he’s skeptical such objects even exist. “Redshift 17 is only 230 million years after the Big Bang,” he said. “This is such a short period that there is still the question of whether there are any such early galaxies.”

There’s only one way to be sure. Take a close look at the likely redshift-13 galaxies then continue to look farther and farther to the edge of the universe, looking for galaxies that are getting older — and redder —. It all started with the safe deployment of the James Webb Space Telescope.

Good news on that front. Earlier this week, the giant telescope open successfully its tennis court-sized sunshade. On Saturday it will the ending opens the second of its two main wing mirrors, meaning it has finally completed the rollout of its largest components and is ready to begin testing its devices. The wait has been huge, but it would be worth it if we could uncover some of the biggest secrets of the universe.