Free Republic

Explanation: What does the Milky Way look like in radio waves? To better find out, GLEAM surveyed the central band of our galaxy in high resolution radio light as imaged by the Murchison Widefield Array in Australia. As the featured video slowly scrolls, radio light (71 - 231 MHz) is seen on the left and visible light -- from the same field -- on the right. Differences are so great because most objects glow differently in radio and visible light, and because visible light is stopped by nearby interstellar dust. These differences are particularly apparent in the direction toward the...

Explanation: This deep field mosaicked image presents a stunning view of galaxy cluster Abell 2744 recorded by the James Webb Space Telescope's NIRCam. Also dubbed Pandora's Cluster, Abell 2744 itself appears to be a ponderous merger of three different massive galaxy clusters. It lies some 3.5 billion light-years away, toward the constellation Sculptor. Dominated by dark matter, the mega-cluster warps and distorts the fabric of spacetime, gravitationally lensing even more distant objects. Redder than the Pandora cluster galaxies, many of the lensed sources are very distant galaxies in the early Universe, their lensed images stretched and distorted into arcs. Of...

An artist’s impression of a large red star releasing a bright, explosive burst of light. Swirling red and orange patterns surround the star, suggesting intense activity. In the background, a smaller blue planet appears with a faint, wispy trail extending away from it, indicating its atmosphere being blown off. The scene is set against a dark space backdrop dotted with stars. Credit: Olena Shmahalo/Callingham et al. Astronomers have, for the first time, confirmed a colossal coronal mass ejection from a distant star, a blast so powerful it could strip the atmosphere from any nearby planet. Astronomers using the European Space...

Hubble captured this image of the interstellar comet 3I/ATLAS on July 21, 2025, when the comet was 277 million miles from Earth. Hubble shows that the comet has a teardrop-shaped cocoon of dust coming off its solid, icy nucleus. Credit: NASA, ESA, David Jewitt (UCLA); Image Processing: Joseph DePasquale (STScI)NASA will host a live event at 3 p.m. EST, Wednesday, Nov. 19, to share imagery of the interstellar comet 3I/ATLAS collected by a number of the agency’s missions. The event will take place at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.Comet 3I/ATLAS, discovered by the NASA-funded ATLAS (Asteroid Terrestrial-impact...

Explanation: What has happened to Comet Lemmon's tail? The answer is blowing in the wind — the wind from the Sun in this case. This continuous outflow of charged particles from the Sun has been quite variable of late, as the Sun emits bursts of energy, CMEs, that push out and deflect charged particles emitted by the comet itself. The result is a blue hued ion tail for Comet C/2025 A6 (Lemmon) that is not only impressively intricate but takes some unusual turns. This long-duration composite image taken from Alfacar, Spain last month captured this inner Solar System ionic tumult....

Explanation: The night side of Pluto spans this shadowy scene. In the stunning spacebased perspective, the Sun is 4.9 billion kilometers (almost 4.5 light-hours) behind the dim and distant world. It was captured by far flung New Horizons in July of 2015 when the spacecraft was at a range of some 21,000 kilometers from Pluto. That was about 19 minutes after its closest approach. A denizen of the Kuiper Belt in dramatic silhouette, the image also reveals Pluto's tenuous, surprisingly complex layers of hazy atmosphere. Near the top of the frame the crescent twilight landscape includes southern areas of nitrogen...

Explanation: If this is Saturn, where are the rings? When Saturn's "appendages" disappeared in 1612, Galileo did not understand why. Later that century, it became understood that Saturn's unusual protrusions were rings and that when the Earth crosses the ring plane, the edge-on rings will appear to disappear. This is because Saturn's rings are confined to a plane many times thinner, in proportion, than a razor blade. In modern times, the robotic Cassini spacecraft that orbited Saturn frequently crossed Saturn's ring plane during its mission to Saturn, from 2004 to 2017. A series of plane crossing images from 2005 February...

Mysterious interstellar object 3I/ATLAS has reemerged from behind the Sun, allowing astronomers to once again get a glimpse at the rare visitor...and is expected to make its closest pass of the Earth just days before Christmas on its way back out of our star system.... .. judging by the latest data, ...Loeb suggests that if 3I/ATLAS really is a visitor from a technological civilization — a possibility he’s floated repeatedly — then it may be trying to boost its exit from the solar system to a breakneck pace. (Let’s face it: getting away from Earth as rapidly as possible makes...

Explanation: This magnificent extragalactic skyscape looks toward the Andromeda Galaxy, the closest large spiral galaxy to the Milky Way. It also accomplishes a Messier catalog trifecta by including Andromeda, cataloged as Messier 31 (M31), along with Messier 32 (M32), and Messier 110 (M110) in the same telescopic field of view. In this frame, M32 is just left of the Andromeda Galaxy's bright core with M110 below and to the right. M32 and M110 are both elliptical galaxies themselves and satellites of the larger spiral Andromeda. By combining 60 hours of broadband and narrowband image data, the deep telescopic view also...

Explanation: Northern lights have come to Florida skies. In fact, the brilliant streak of a Northern Taurid meteor flashes through the starry night sky above the beach in this sea and skyscape, captured from Shired Island, Florida on November 11. Meteors from the annual Northern Taurid meteor shower are expected this time of year. But the digital camera exposure also records the shimmering glow of aurora, a phenomenon more often seen from our fair planet's higher geographical latitudes. Also known as aurora borealis, these northern lights are part of recent, wide spread auroral activity caused by strong geomagnetic storms. In...

Explanation: Few cosmic vistas can excite the imagination like The Great Nebula in Orion. Visible as a faint, bland celestial smudge to the naked-eye, the nearest large star-forming region sprawls across this sharp colorful telescopic image. Designated M42 in the Messier Catalog, the Orion Nebula's glowing gas and dust surrounds hot, young stars. About 40 light-years across, M42 is at the edge of an immense interstellar molecular cloud only 1,500 light-years away that lies within the same spiral arm of our Milky Way galaxy as the Sun. Including dusty bluish reflection nebula NGC 1977, also known as the Running Man...

In today’s weather forecast, we are talking about a rare and spectacular northern lights display expected to light up skies across much of the United States. tonight. A powerful geomagnetic storm is underway, allowing the aurora to be visible as far south as the central Plains, Ohio Valley, and even parts of the Deep South. Skies will need to be clear and dark, so head away from city lights for the best chance to see it. Infrastructure impacts, like power grid issues, cannot be ruled out. This is one of the most widespread aurora events in years, get all the...

Explanation: Beautiful island universe Messier 94 lies a mere 15 million light-years distant in the northern constellation of the hunting dogs, Canes Venatici. A popular target for earth-based astronomers, the face-on spiral galaxy is about 30,000 light-years across, with spiral arms sweeping through the outskirts of its broad disk. But this Hubble Space Telescope field of view spans about 7,000 light-years or so across M94's central region. The sharp close-up examines the galaxy's compact, bright nucleus and prominent inner dust lanes, surrounded by a remarkable bluish ring of young, massive stars. The massive stars in the ring are all likely...

The Sun has just fired off its most powerful solar flare of 2025, causing radio blackouts across half the globe. As the barrage of charged particles makes its way toward Earth, the aurorae borealis – or Northern Lights – could become visible at unusually low latitudes tonight. Solar flares are bursts of electromagnetic radiation that arise from tangles in the Sun’s magnetic field, and travel through space at the speed of light. The strongest of these are categorized as X-flares, three of which have now been recorded in the past few days. The first two were detected on November 9...

Explanation: One of the brightest galaxies in planet Earth's sky is similar in size to our Milky Way Galaxy: big, beautiful M81. The grand spiral galaxy can be found toward the northern constellation of the Great Bear (Ursa Major). This superbly detailed image reveals M81's bright yellow nucleus, blue spiral arms, tell tale pinkish star forming regions, and sweeping cosmic dust lanes with a scale comparable to the Milky Way. Hinting at a disorderly past, a remarkable dust lane actually runs straight through the disk, to the left of the galactic center, contrary to M81's other prominent spiral features. The...

The 42-day federal shutdown forced by Democrats thrust the economics of Obamacare into the limelight, and exposed an uncomfortable truth: An insurance industry whose executives are increasingly liberal donors has seen its earnings soar with the injection of taxpayer-funded subsidies that propped up Barack Obama's signature health program from collapse. The nation’s largest health insurance companies have seen good business since Obamacare was first passed in 2010 and fully implemented in 2014. This has come in no small part because of federal government subsidies to the insurance industry, which government estimates show totaled $1.8 trillion in 2023 alone. Those subsidies...

For the first time, astronomers have picked up a radio signal from the mysterious interstellar visitor as it speeds through our Solar System. South Africa's MeerKAT radio telescope detected absorption lines from OH molecules...Harvard professor Avi Loeb, who has been studying 3I/ATLAS since the summer, said: 'These molecules leave a distinct radio signature that telescopes like MeerKAT can pick up.'... Optical images captured on November 9 reveal that 3I/ATLAS is ejecting enormous jets of material both toward and away from the sun. The jets stretch nearly 600,000 miles sunward and almost 1.8 million miles in the opposite direction, roughly the...

Explanation: Clouds of glowing gas mingle with dust lanes in the Trifid Nebula, a star forming region toward the constellation of the Archer (Sagittarius). In the center, the three prominent dust lanes that give the Trifid its name all come together. Mountains of opaque dust appear on the right, while other dark filaments of dust are visible threaded throughout the nebula. A single massive star visible near the center causes much of the Trifid's glow. The Trifid, also known as M20, is only about 300,000 years old, making it among the youngest emission nebulae known. The nebula lies about 9,000...

Earth's orbit is not a perfect circle. It is elliptical, or slightly oval-shaped. This means there is one point in the orbit where Earth is closest to the Sun, and another where Earth is farthest from the Sun. The closest point occurs in early January, and the far point happens in early July (July 7, 2007). If this is the mechanism that causes seasons, it makes some sense for the Southern Hemisphere. But, as an explanation for the Northern Hemisphere, it fails miserably.In fact, Earth's elliptical orbit has nothing to do with seasons. The reason for seasons was explained in...

Explanation: Big, bright, and beautiful, spiral galaxy M83 lies a mere twelve million light-years away, near the southeastern tip of the very long constellation Hydra. Prominent spiral arms traced by dark dust lanes and blue star clusters lend this galaxy its popular name, The Southern Pinwheel. But reddish star forming regions that dot the sweeping arms highlighted in this sparkling color composite also suggest another nickname, The Thousand-Ruby Galaxy. About 40,000 light-years across, M83 is a member of a group of galaxies that includes active galaxy Centaurus A. In fact, the core of M83 itself is bright at x-ray energies,...