The first words of the book of Genesis make a declarative statement. God created Heaven and Earth, and thus begins the cosmic story. While not all creation myths have an act of beginning, most do. Humans are storytellers, and we like stories with a beginning. This origin need is deep within us and is even part of our scientific worldview. As is so often said in science, effects have causes. This cause and effect process is a powerful tool for understanding the world around us, but it’s not without its problems, particularly with the origin of the universe.
According to a new study by an international team of scientists, the JWST will allow astronomers to obtain accurate mass measurements of early galaxies. Using data from James Webb’s Near-Infrared Camera (NIRCam), which was provided through the GLASS-JWST-Early Release Science (GLASS-ERT) program, the team obtained mass estimates from some of the distant galaxies that were many times more accurate than previous measurements. Their findings illustrate how Webb will revolutionize our understanding of how the earliest galaxies in the Universe grew and evolved.
Now that the James Webb Space Telescope is operational, astronomers can study some of the most faint and distant galaxies ever seen. By some accounts, we may have already captured the image of a galaxy from when the universe was just 300 million years old. But we can’t be entirely sure of its distance, and that is a big problem for astronomers.
By now, almost everyone has seen the first-release images from JWST and marveled at these amazing views of the infrared universe the telescope was launched to explore. The view of SMACS 0723 seen above illustrates the promise JWST holds. While there are many more early-release images in the observation pipeline, we’re starting to see the first research papers come out. As expected, studies of distant galaxies are grabbing headlines already.
Wow, are these findings amazing! In the last couple of days, websites and social media have been alive with images of a blob that, in reality, is one of the oldest (earliest) galaxies ever seen. It’s one of two—GL-z11 and GL-z13—that show us what they looked like when the Universe was extremely young, about 300 million years after the Big Bang. When confirmed, they’ll mark a milestone in studies of the infant Universe.
The Universe’s giant galaxies pose a thorny problem for astronomers. The galaxies have grown large somehow, and the only things that can make a galaxy giant are probably other galaxies. So mergers must have played an important role.
Astronomers have known about galaxy mergers for a long time, but the process is still mysterious. A new study based on ten years of work presents observations and direct measurements of the galaxy merger process that remove some of the mystery.
Studying the universe is hard. Really hard. Like insanely, ridiculously hard. Think of the hardest thing you’ve ever done in your life, because studying the universe is quite literally exponentially way harder than whatever you came up with. Studying the universe is hard for two reasons: space and time. When we look at an object in the night sky, we’re looking back in time, as it has taken a finite amount of time for the light from that object to reach your eyes. The star Sirius is one of the brightest objects in the night sky and is located approximately 8.6 light-years from Earth. This means that when you look at it, you’re seeing what it looked like 8.6 years ago, as the speed of light is finite at 186,000 miles per second and a light year is the time it takes for light to travel in one year. Now think of something way farther away than Sirius, like the Big Bang, which supposedly took place 13.8 billion years ago. This means when scientists study the Big Bang, they’re attempting to look back in time 13.8 billion years. Even with all our advanced scientific instruments, it’s extremely hard to look back that far in time. It’s so hard that the Hubble Space Telescope has been in space since 1990 and just recently spotted the most distant single star ever detected in outer space at 12.9 billion light-years away. That’s 30 years of scanning the heavens, which is a testament to the vastness of the universe, and hence why studying the universe is hard. Because studying the universe is so hard, scientists often turn to computer simulations, or models, to help speed up the science aspect and ultimately give us a better understanding of how the universe works without waiting 30 years for the next big discovery.
The idea of a mirror universe is a common trope in science fiction. A world similar to ours where we might find our evil doppelganger or a version of us who actually asked out our high school crush. But the concept of a mirror universe has been often studied in theoretical cosmology, and as a new study shows, it might help us solve problems with the cosmological constant.
Since the Renaissance astronomer Galileo Galilee first studied the heavens using a telescope he built himself, astronomers have been pushing the boundaries of what they can observe. After centuries of progress, they have been able to study and catalog objects in all but the earliest periods of the Universe. But thanks to next-generation instruments and technologies, astronomers will soon be able to observe the “Cosmic Dawn” era – ca. 50 million to billion years after the Big Bang.
In recent years, astronomers have made discoveries that preview what this will be like, the most recent of which is the galaxy candidate known as HD1. This galaxy is about 13.5 billion light-years from Earth (32.2 billion light-years in terms of “proper distance“), making it the farthest ever observed. This discovery implies that galaxies existed as early as 300 million years after the Big Bang, a finding which could have drastic implications for astronomy and cosmology!
The fields of astronomy and astrophysics are poised for a revolution in the coming years. Thanks to next-generation observatories like the James Webb Space Telescope (JWST), scientists will finally be able to witness the formation of the first stars and galaxies in the Universe. In effect, they will be able to pierce the veil of the Cosmic Dark Ages, which lasted from roughly 370,000 years to 1 billion years after the Big Bang.
NASA’s Nancy Gracy Roman Space Telescope won’t launch until 2027, and it won’t start operating until some time after that. But that isn’t stopping excited scientists from dreaming about their new toy and all it will do. Who can blame them?
A new study examines the Roman Space Telescope’s power in detail to see if it can help us answer one of our most significant questions about the Universe. The question?
Will the Universe keep expanding and tear itself apart in a Big Rip?