Universe Today (Page 27)

We Just had the Strongest Solar Flare in the Current Solar Cycle On December 14th, at 12:02 PM Eastern (09:02 AM Pacific), the Sun unleashed a massive solar flare. According to the Space Weather Prediction Center, part of the National Oceanic Atmospheric Administration (NOAA), this was the strongest flare of Solar Cycle 25, which began in 2019 and will continue until 2030. What’s more, scientists at the SWPC estimate that this may be one of the most powerful solar flares recorded since 1755 when extensive recording of solar sunspot activity began. Solar flares occur in the Sun’s active regions, and activity varies over an 11-yearRead More →

It’s Time for Saturn’s “Spokes” to Return Astronomers have been observing Saturn with the Hubble Space Telescope and several other spacecraft for decades and have noticed something unusual. During seasonal changes, transient spoke-like features appear in the rings. These dark, ghostly blobs orbit around the planet 2-3 times, and then disappear. As Saturn is approaching its equinox, this is prime spoke activity time. Once again, Hubble has been called to gaze at Saturn, tracking the behavior of the spokes and hopefully giving astronomers more clues as to why they occur. Earlier this year in February, Hubble took an image showing the spokes only on oneRead More →

Finally. A Productive Use for Nuclear Weapons: Asteroid Defence While it has been a favorite disaster movie theme, nuking an incoming asteroid in the real world has been touted as a very bad idea. While a nuclear bomb could possibly obliterate a smaller asteroid, nuking a larger asteroid would only break it into pieces. Those pieces would still threaten our planet, and perhaps even makes things worse by producing multiple impacts across the planet.   But is using nuclear weapons on an incoming asteroid really a bad idea? If the right technique is used, a nuclear blast could possibly be used as an asteroid deflectionRead More →

Why the Universe Might be a Hologram A quarter century ago, physicist Juan Maldacena proposed the AdS/CFT correspondence, an intriguing holographic connection between gravity in a three-dimensional universe and quantum physics on the universe’s two-dimensional boundary. This correspondence is at this stage, even a quarter century after Maldacena’s discovery, just a conjecture. A statement about the nature of the universe that seems to be true, but one that has not yet been proven to actually reflect the reality that we live in. And what’s more, it only has limited utility and application to the real universe. Still, even the mere appearance of the correspondence isRead More →

It Doesn’t Take Much to Get a Runaway Greenhouse Effect During the 1960s, the first robotic explorers began making flybys of Venus, including the Soviet Venera 1 and the Mariner 2 probes. These missions dispelled the popular myth that Venus was shrouded by dense rain clouds and had a tropical environment. Instead, these and subsequent missions revealed an extremely dense atmosphere predominantly composed of carbon dioxide. The few Venera landers that made it to the surface also confirmed that Venus is the hottest planet in the Solar System, with average temperatures of 464 °C (867 °F). These findings drew attention to anthropogenic climate change andRead More →

Enjoy the Holiday-Themed Christmas Tree Cluster Just in time for the holidays, a new composite image of the Christmas Tree Cluster (NGC 2264) has been released. This image is a group effort: the blue and white stars in the cluster giving off X-rays are seen by Chandra, while the faint green nebula was imaged by the WIYN 0.9-meter telescope on Kitt Peak. NGC 2264 is a cluster of young stars about 2,500 light-years from Earth with ages between one and five million years old, ranging in mass from greater than the Sun to 1/10th a solar mass. To show the Christmas Tree shape us humansRead More →

Astronomers Find the Birthplaces of Stars in the Whirlpool Galaxy Understanding how star-forming works at a galactic scale is challenging in our Milky Way. While we have a general understanding of the layout of our galaxy, we can’t see all of the details head-on like we would want to if we were exploring a single galaxy for details of star formation. Luckily, we have a pretty good view of the entirety of one of the most famous galaxies in all of astronomy – M51, the Whirlpool Galaxy. Now, a team of researchers from the Max Planck Institute for Astronomy has completed a survey of moleculesRead More →

The Strangest Coincidence in Physics: The AdS/CFT Correspondence Attempts to turn string theory into a workable theory of nature have led to the potential conclusion that our universe is a hologram: that what we perceive as three spatial dimensions is actually composed of only two. The greatest realization of this hologram-led program is a proposal that goes by the awkward and clunky name of the AdS/CFT correspondence, first proposed by string theorist Juan Maldacena in the late 1990’s. The AdS/CFT correspondence is not a solution to the problems posed by string theory per se, but a statement motivated by advances in the theory when oneRead More →

A New View of Uranus’ North Pole from JWST One cool thing about Uranus is that its orientation, compared to the rest of the solar system, allows a unique perspective of the planet from our home planet. It is tilted at 98° compared to the rest of the ecliptic plane. So, when viewed from Earth, we can see its North Pole and its rings in some exceptional cases. That perspective is fully displayed in an image of Uranus recently released by the European Space Agency (ESA) and captured using the James Webb Space Telescope (JWST).  JWST is the most powerful space telescope currently in service,Read More →

Blue Origin’s New Shepard Completes 24th Flight; New Glenn Hopefully on the Horizon Blue Origin’s New Shepard rocket successfully launched and landed today at the company’s Launch Site One in West Texas, with an uncrewed science and goodwill payload onboard. This was the 24th New Shepard flight and 13th payload mission today from Launch Site One in West Texas. This marked the first flight since September of 2022 when the uncrewed NS-23’s booster suffered an in-flight anomaly; however, the escape system jettisoned the capsule, which was able to land safely. With the success of NS-24, Blue Origin hopes to soon restart its commercial passenger flights.Read More →

Can Webb Find the First Stars in the Universe? The Universe’s very first stars had an important job. They formed from the primordial elements created by the Big Bang, so they contained no metals. It was up to them to synthesize the first metals and spread them out into the nearby Universe. The JWST has made some progress in finding the Universe’s earliest galaxies. Can it have the same success when searching for the first stars? Finding the Universe’s first galaxies is an extremely difficult task and one of the main motivations behind building the JWST. Light from these ancient objects is red-shifted into theRead More →

Astronomers Find Two Planetary Systems Around Sun-Like Stars NASA’s Transiting Exoplanet Survey Satellite (TESS) has been busy. Clocking in over 5000 exoplanet candidates, the researchers who manage the telescope’s data have enlisted an army of volunteer classifiers to sift through its data to confirm whether these planets exist. In a new paper in Astronomy & Astrophysics, some researchers from Brazil think they have found three planets that almost certainly do – and they happen to orbit stars that are very similar to our own Sun. The planets were located in two separate star systems, known as TOI-2141 and TOI-1736, respectively. TOI-2141 is located about 250Read More →

A Radio Telescope on the Moon Could Help Us Understand the First 50 Million Years of the Universe In the coming decade, multiple space agencies and commercial space providers are determined to return astronauts to the Moon and build the necessary infrastructure for long-duration stays there. This includes the Lunar Gateway and the Artemis Base Camp, a collaborative effort led by NASA with support from the ESA, CSA, and JAXA, and the Russo-Chinese International Lunar Research Station (ILRS). In addition, several agencies are exploring the possibility of building a radio observatory on the far side of the Moon, where it could operate entirely free ofRead More →

Why String Theory Requires Extra Dimensions String theory found its origins in an attempt to understand the nascent experiments revealing the strong nuclear force. Eventually another theory, one based on particles called quarks and force carriers called gluons, would supplant it, but in the deep mathematical bones of the young string theory physicists would find curious structures, half-glimpsed ghosts, that would point to something more. Something deeper. String theory claims that what we call particles – the point-like entities that wander freely, interact, and bind together to make up the bulk of material existence – are nothing but. Instead, there is but a single kindRead More →

Millions of Satellites Could Have a Profound Effect on the Earth’s Ionosphere Hardly a day goes by where a story hits the headlines about our abuse of the Earth’s precious environment be that the atmosphere or the oceans, forests or desert. When it comes to the atmosphere we all tend to immediately turn our attention to pollution, to gasses being released and disturbing the delicate balance. Yet a paper recently published points to a new demon, megaconstellations of satellites damaging the ionosphere – the ionised part of the upper atmosphere. It was back in 1957 that the Sputnik, the first artificial satellite was put intoRead More →

The Holographic Secret of Black Holes As weird as it might sound, black holes appear to be holograms. In the 1980’s physicist Jacob Bekenstein was able to calculate exactly how much a black hole grew. If you add a single bit of information to a black hole, its surface area increases by exactly one Planck unit.A Planck length the smallest possible measurable distance, roughly 10^-35 meters, and is important because it’s right around that scale where our understanding of physics completely breaks down. Specifically, it’s at that scale that we believe that we require a quantum theory of gravity to understand what’s going on. ARead More →

Astronomers Scan Hundreds of Stars for “Anomalous Transits” Telescopes have been collecting copious amounts of data on exoplanets in recent years. One of the most common datasets tracks what are known as “transits,” where an exoplanet crosses in front of its host star and dims the star’s light slightly as it does so. The majority of exoplanets have been found this way, but other interesting details might be hidden in the data. For example, what would it mean if the transits happened in a way that disagreed with typical Newtonian physics? One answer to that question is that there might be an intelligent force behindRead More →

Toxic Gas is Leaking out of Enceladus. It’s also a Building Block of Life. Enceladus’ status as a target in the search for life keeps rising. We’ve known for years that plumes erupting from the ocean under the moon’s icy shell contain important organic compounds related to life. Now, researchers have found another chemical in the plumes which is not only highly toxic but also critical in the appearance of life. The Cassini spacecraft spent 13 years in the Saturn system before ending its mission in 2017. Among its many discoveries were plumes erupting from Saturn’s moon Enceladus. The images of the plumes are iconic.Read More →

Scientists are Recommending IceCube Should be Eight Times Bigger The IceCube Neutrino Observatory, operated by the University of Wisconsin-Madison (UW-M), located at the Amundsen–Scott South Pole Station in Antarctica, is one of the most ambitious neutrino observatories in the world. Behind this observatory is the IceCube Collaboration, an international group of 300 physicists from 59 institutions in 14 countries. Relying on a cubic kilometer of ice to shield from external interference, this observatory is dedicated to the search for neutrinos. These nearly massless subatomic particles are among the most abundant in the Universe and constantly pass through normal matter. By studying these particles, scientists hopeRead More →

Could There Be a Black Hole Inside the Sun? It’s a classic tale of apocalyptic fiction. The Sun, our precious source of heat and light, collapses into a black hole. Or perhaps a stray black hole comes along and swallows it up. The End is Nigh! If a stellar-mass black hole swallowed our Sun, then we’d only have about 8 minutes before, as the kids say, it gets real. But suppose the Sun swallowed a small primordial black hole? Then things get interesting, and that’s definitely worth a paper on the arXiv. Primordial black holes are hypothetical black holes that formed during the earliest momentsRead More →