It’s an exciting time in astronomy today, where records are being broken and reset regularly. We are barely two months into 2024, and already new records have been set for the farthest black hole yet observed, the brightest supernova, and the highest-energy gamma rays from our Sun. Most recently, an international team of astronomers using the ESO’s Very Large Telescope in Chile reportedly saw the brightest object ever observed in the Universe: a quasar (J0529-4351) located about 12 billion light years away that has the fastest-growing supermassive black hole (SMBH) at its center.Continue reading “The Brightest Object Ever Seen in the Universe”
Approximately 13.8 billion years ago, the greatest event in all of existence occurred that literally created existence itself. This event is known as the Big Bang, and it’s responsible for the estimated septillion number of stars that are scattered across the vast reaches of the unknown, including the one our small, blue world orbits. However, other than knowing that the Big Bang occurred, there is still a septillion amount of information we still don’t know about the greatest event in the history of existence.Continue reading “The Big Bang: What is it? Why study it? What happened before? How will it all end?”
After years of build-up and anticipation, the James Webb Space Telescope finally launched into orbit on December 25th, 2021 (what a Christmas present, huh?). Since then, the stunning images and data it has returned have proven beyond a doubt that it was the best Christmas present ever! After its first year of operations, the JWST has lived up to one of its primary objectives: to observe the first stars and galaxies that populated the Universe. The next-generation observatory has accomplished that by setting new distance records and revealing galaxies that existed less than 1 billion years after the Big Bang!
These studies are essential to charting the evolution of the cosmos and resolving issues with our cosmological models, like the Hubble Tension and the mysteries of Dark Matter and Dark Energy. Well, hang onto your hats because things have reached a new level of awesome! In a recent study, an international team of scientists isolated a well-magnified star candidate in a galaxy that appears as it was almost 12.5 billion years ago. The detection of a star that existed when the Universe was only ~1.2 billion years old showcases the abilities of the JWST and offers a preview of what’s to come!Continue reading “JWST Plucks One Single Star out of a Galaxy Seen 12.5 Billion Years Ago”
One of the main objectives of the James Webb Space Telescope (JWST) is to use its powerful optics and advanced instruments to observe the earliest galaxies in the Universe. These galaxies formed about 1 billion years after the Big Bang, coinciding with the end of what is known as the “Cosmic Dark Ages.” This epoch is inaccessible for conventional optical telescopes because the only sources of photons were largely associated with the relic radiation of the Big Bang – visible today as the Cosmic Microwave Background (CMB) – or were the result of the reionization of neutral hydrogen (visible today the 21 cm line).
Thanks to its advanced optics and infrared imaging capabilities, Webb has pushed the boundaries of how far astronomers and cosmologists can see. One of the most interesting finds was Maisie’s galaxy, which appeared to have existed roughly 390 million years after the Big Bang. According to a new study by the Cosmic Evolution Early Release Science Survey (CEERS) that recently appeared in Nature, these results have since been confirmed. This makes Maisie’s galaxy one of the farthest (and earliest) confirmed galaxies ever observed by human eyes.Continue reading “You’re Looking at One of the Farthest Confirmed Galaxies Found by JWST”
A recent study published in the Proceedings of the National Academy of Sciences (PNAS) examines what are known as dark stars, which are estimated to be much larger than our Sun, are hypothesized to have existed in the early universe, and are allegedly powered by the demolition of dark matter particles. This study was conducted using spectroscopic analysis from NASA’s James Webb Space Telescope (JWST), and more specifically, the JWST Advanced Deep Extragalactic Survey (JADES), and holds the potential to help astronomers better understand dark stars and the purpose of dark matter, the latter of which continues to be an enigma for the scientific community, as well as how it could have contributed to the early universe.Continue reading “Have We Seen the First Glimpse of Supermassive Dark Stars?”
When astronomers used the JWST to look at a galaxy more than 12 billion light years away, they were also looking back in time. And when they found organic molecules in that distant galaxy, they found them in the early Universe.
The organic molecules are usually found where stars are forming, but in this case, they’re not.Continue reading “JWST Sees Organic Molecules Ludicrously Far Away”
According to the most widely-accepted model of cosmology, the Universe began roughly 13.8 billion years ago with the Big Bang. As the Universe cooled, the fundamental laws of physics (the electroweak force, the strong nuclear force, and gravity) and the first hydrogen atoms formed. By 370,000 years after the Big Bang, the Universe was permeated by neutral hydrogen and very few photons (the Cosmic Dark Ages). During the “Epoch of Reionization” that followed, the first stars and galaxies formed, reoinizing the neutral hydrogen and causing the Universe to become transparent.
For astronomers, the Epoch of Reionization still holds many mysteries, like when certain heavy elements formed. This includes the element carbon, a key ingredient in the formation of planets, an important element in organic processes, and the basis for life as we know it. According to a new study by the ARC Center of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), it appears that triply-ionized carbon (C iv) existed far sooner than previously thought. Their findings could have drastic implications for our understanding of cosmic evolution.Continue reading “Warm Carbon Increased Suddenly in the Early Universe. Made by the First Stars?”
According to the most widely-accepted cosmological theories, the Universe began roughly 13.8 billion years ago in a massive explosion known as the Big Bang. Ever since then, the Universe has been in a constant state of expansion, what astrophysicists know as the Hubble Constant. For decades, astronomers have attempted to measure the rate of expansion, which has traditionally been done in two ways. One consists of measuring expansion locally using variable stars and supernovae, while the other involves cosmological models and redshift measurements of the Cosmic Microwave Background (CMB).
Unfortunately, these two methods have produced different values over the past decade, giving rise to what is known as the Hubble Tension. To resolve this discrepancy, astronomers believe that some additional force (like “Early Dark Energy“) may have been present during the early Universe that we haven’t accounted for yet. According to a team of particle physicists, the Hubble Tension could be resolved by a “New Early Dark Energy” (NEDE) in the early Universe. This energy, they argue, would have experienced a phase transition as the Universe began to expand, then disappeared.Continue reading “Could a Dark Energy Phase Change Relieve the Hubble Tension?”
Black holes swallow everything—including light—which explains why we can’t see them. But we can observe their immediate surroundings and learn about them. And when they’re on a feeding binge, their surroundings become even more luminous and observable.
This increased luminosity allowed astronomers to find a black hole that was feasting on material only 800 million years after the Universe began.Continue reading “Hungry Black Hole was Already Feasting 800 Million Years After the Big Bang”
The frontiers of astronomy are being pushed regularly these days thanks to next-generation telescopes and scientific collaborations. Even so, astronomers are still waiting to peel back the veil of the cosmic “Dark Ages,” which lasted from roughly 370,000 to 1 billion years after the Big Bang, where the Universe was shrouded with light-obscuring neutral hydrogen. The first stars and galaxies formed during this same period (ca. 100 to 500 million years), slowly dispelling the “darkness.” This period is known as the Epoch of Reionization, or as many astronomers call it: Cosmic Dawn.
By probing this period with advanced radio telescopes, astronomers will gain valuable insights into how the first galaxies formed and evolved. This is the purpose of the Hydrogen Epoch of Reionization Array (HERA), a radio telescope dedicated to observing the large-scale structure of the cosmos during and before the Epoch of Reionization located in the Karoo desert in South Africa. In a recent paper, the HERA Collaboration reports how it doubled the array’s sensitivity and how their observations will lead to the first 3D map of Cosmic Dawn.Continue reading “Astronomers are Working on a 3D map of Cosmic Dawn”