Some galaxies experience rapid star formation hundreds or even thousands of times greater than the Milky Way. Astronomers think that mergers are behind these special galaxies, which were more abundant in the earlier Universe. But new results suggest no mergers are needed.
Continue reading “No Merger Needed: A Rotating Ring of Gas Creates A Hyperluminous Galaxy”Galaxies Regulate their Own Growth so they Don’t Run Out of Star Forming Gas
Look at most spiral or barred spiral galaxies and you will see multiple regions where stars are forming. These star forming regions are comprised of mostly hydrogen gas with a few other elements for good measure. The first galaxies in the Universe had huge supplies of this star forming gas. Left unchecked they could have burned through the gas quickly, generating enormous amounts of star formation. Life fast though and die young for such an energetic burst of star formation would soon fizzle out leaving behind dead and dying stars. In some way it seems, galaxies seem to regulate their star formation thanks to supermassive black holes at their centre.
Continue reading “Galaxies Regulate their Own Growth so they Don’t Run Out of Star Forming Gas”Galaxies Filled With Old Stars Seen Shortly After the Big Bang
How can young galaxies in the early Universe have ancient stars? That’s the question a team of astronomers set out to answer using JWST as a probe. They first spotted the massive objects in 2022 and are still working to explain what these things are.
Continue reading “Galaxies Filled With Old Stars Seen Shortly After the Big Bang”Growing Black Holes Have Much in Common With Baby Stars
First looks would tell most observers that supermassive black holes (SMBHs) and very young stars have nothing in common. But that’s not true. Astronomers have detected a supermassive black hole (SMBH) whose growth is regulated the same way a baby star’s is: by magnetic winds.
Continue reading “Growing Black Holes Have Much in Common With Baby Stars”Here’s Hubble’s First Image in its New Pointing Mode
This is probably what the demise of the Hubble Space Telescope was always going to look like: components failing one by one, with no way to replace them. In the last few months, the Hubble has repeatedly gone into safe mode as one of its remaining three gyros keeps giving faulty readings. But the Hubble and the people operating it are resilient and resourceful. The telescope is back to science operations now, though in single gyro mode.
NASA has released the first image the Hubble captured in this mode, and it’s clear that the Hubble is performing well.
Continue reading “Here’s Hubble’s First Image in its New Pointing Mode”Almost a Third of Early Galaxies Were Already Spirals
In the years before the JWST’s launch, astronomers’ efforts to understand the early Universe were stymied by a stubborn obstacle: the light from the early Universe was red-shifted to an extreme degree. The JWST was built with extreme redshifts in mind, and one of its goals was to study Galaxy Assembly.
Once the JWST activated its segmented, beryllium eye, the Universe’s most ancient, red-shifted light became visible.
Continue reading “Almost a Third of Early Galaxies Were Already Spirals”The Milky Way’s Last Merger Event Was More Recent Than Thought
The Milky Way is only as massive as it is because of collisions and mergers with other galaxies. This is a messy process, and we see the same thing happening with other galaxies throughout the Universe. Currently, we see the Milky Way nibbling at its two satellite galaxies, the Large and Small Magellanic Clouds. Their fate is likely sealed, and they’ll be absorbed into our galaxy.
Researchers thought the last major merger occurred in the Milky Way’s distant past, between 8 and 11 billion years ago. But new research amplifies the idea that it was much more recent: less than 3 billion years ago.
Continue reading “The Milky Way’s Last Merger Event Was More Recent Than Thought”Evidence of Dark Matter Interacting With Itself in El Gordo Merger
The Standard Model of particle physics does a good job of explaining the interactions between matter’s basic building blocks. But it’s not perfect. It struggles to explain dark matter. Dark matter makes up most of the matter in the Universe, yet we don’t know what it is.
The Standard Model says that whatever dark matter is, it can’t interact with itself. New research may have turned that on its head.
Continue reading “Evidence of Dark Matter Interacting With Itself in El Gordo Merger”Webb Finds the Farthest Galaxy Ever Seen (So Far)
There are some things that never cease to amaze me and the discovery of distant objects is one of them. The James Webb Space Telescope has just found the most distant galaxy ever observed! It has the catchy title JADES-GS-z14-0 and it has a redshift of 14.32. This means its light left when the Universe was only 290 million years old! That means the light left the source LOOOONG before even our Milky Way was here! How amazing is that!
Continue reading “Webb Finds the Farthest Galaxy Ever Seen (So Far)”Galaxies in the Early Universe Preferred their Food Cold
One of the main objectives of the James Webb Space Telescope (JWST) is to study the early Universe by using its powerful infrared optics to spot the first galaxies while they were still forming. Using Webb data, a team led by the Cosmic Dawn Center in Denmark pinpointed three galaxies that appear to have been actively forming just 400 to 600 million years after the Big Bang. This places them within the Era of Reionization, when the Universe was permeated by opaque clouds of neutral hydrogen that were slowly heated and ionized by the first stars and galaxies.
This process caused the Universe to become transparent roughly 1 billion years after the Big Bang and (therefore) visible to astronomers today. When the team consulted the data obtained by Webb, they observed that these galaxies were surrounded by an unusual amount of dense gas composed almost entirely of hydrogen and helium, which likely became fuel for further galactic growth. These findings already reveal valuable information about the formation of early galaxies and show how Webb is exceeding its mission objectives.
Continue reading “Galaxies in the Early Universe Preferred their Food Cold”