Space and astronomy news
Astronomers know that galaxies form through mergers. They’ve been happening since the earliest epochs of cosmic time. Using the Webb telescope (JWST) astronomers found a massive merger of young galaxies going on about a half million years after the Big Bang. It’s called Gz9p3, one of the earliest and most distant mergers ever witnessed.
Continue reading “Webb Watches the Most Distant Galactic Merger Ever Seen”
The Earth’s place in space is a fairly familiar one with it orbiting an average star. The star – our Sun – orbits the centre of our Galaxy the Milky Way. From here onwards, the story is less well known. The Milky Way is part of a large structure called the Laniakea Supercluster which is 250 million light years across! That really is a whacking great area of space and it contains at least 100,000 galaxies. There are larger superclusters though like the newly discovered Einasto Supercluster which measures an incredible 360 million light years across and is home to 26 quadrillion stars!
Continue reading “Astronomers Find the Most Massive Supercluster to Date”
I often drag out the amazing fact that the Andromeda Galaxy, that faint fuzzy blob just off the corner of the Square of Pegasus, is heading straight for us! Of course I continue to tell people it won’t happen for a few billion years yet but a recent study suggests that we are already seeing hypervelocity stars that have been ejected from Andromeda already. It is just possible that the two galaxies have already started to exchange stars long before they are expected to merge.
Continue reading “Are Andromeda and the Milky Way Already Exchanging Stars?”
The Universe is filled with supermassive black holes. Almost every galaxy in the cosmos has one, and they are the most well-studied black holes by astronomers. But one thing we still don’t understand is just how they grew so massive so quickly. To answer that, astronomers have to identify lots of black holes in the early Universe, and since they are typically found in merging galaxies, that means astronomers have to identify early galaxies accurately. By hand. But thanks to the power of machine learning, that’s changing.
Continue reading “Black Holes Need Refreshing Cold Gas to Keep Growing”
When a galaxy runs out of gas and dust, the process of star birth stops. That takes billions of years. But, there’s a galaxy out there that was already dead when the Universe was only 700 million years old. What happened to it?
Continue reading “This Galaxy Was Already Dead When the Universe Was Only 700 Million Years Old”
During the Universe’s Dark Ages, dense primordial gas absorbed and scattered light, prohibiting it from travelling. Only when the first stars and galaxies began to shine in energetic UV light did the Epoch of Reionization begin. The powerful UV light shone through the Universe and punched holes in the gas, allowing light to travel freely.
New observations with the James Webb Space Telescope reveal how it happened. The telescope shows that faint dwarf galaxies brought an end to the darkness.
Continue reading “Dwarf Galaxies Banished the Darkness and Lit Up the Early Universe”
Supermassive black holes are messy feeders, and when they’re gorging on too much material, they can hurl high-energy jets into the surrounding Universe. Astronomers have found one of the most powerful eruptions ever seen, emanating from a black hole 3.8 billion light-years away. The powerful jets are blowing out cavities in intergalactic space and triggering the formation of a huge chain of star clusters.
Continue reading “Powerful Jets From a Black Hole are Spawning Star Clusters”
The gigantic galaxies we see in the Universe today, including our own Milky Way galaxy, started out far smaller. Mergers throughout the Universe’s 13.7 billion years gradually assembled today’s massive galaxies. But they may have begun as mere star clusters.
In an effort to understand the earliest galaxies, the JWST has examined their ancient light for clues as to how they became so massive.
Continue reading “JWST Sees a Milky Way-Like Galaxy Coming Together in the Early Universe”
For a long time, our understanding of the Universe’s first galaxies leaned heavily on theory. The light from that age only reached us after travelling for billions of years, and on the way, it was obscured and stretched into the infrared. Clues about the first galaxies are hidden in that messy light. Now that we have the James Webb Space Telescope and its powerful infrared capabilities, we’ve seen further into the past—and with more clarity—than ever before.
The JWST has imaged some of the very first galaxies, leading to a flood of new insights and challenging questions. But it can’t see individual stars.
How can astronomers detect their impact on the Universe’s first galaxies?
Continue reading “Even if We Can’t See the First Stars, We Could Detect Their Impact on the First Galaxies”
The poetic-minded among us like to point out how Nature is a dance. If they’re right, then galaxies sometimes form unwieldy pairs. With the Hubble Space Telescope, we can spot some of these galactic pairs as they approach one another.
Continue reading “Hubble Sees a Bridge of Stars Connecting Two Galaxies”