Free Republic

0:00 Proximity of Stars 1:28 110 AU Range 5:00 HD 7977's Oort Cloud Disruption 10:08 Scholz's Star Stars that Brushed Past the Solar System | 12:44 Territory | 122K subscribers | 408,226 views | August 8, 2026

Scholz's star -- named after the German astronomer who discovered it -- approached less than a light-year from the Sun. Nowadays it is almost 20 light-years away, but 70,000 years ago it entered the Oort cloud, a reservoir of trans-Neptunian objects located at the confines of the solar system. ... Now two astronomers from the Complutense University of Madrid, the brothers Carlos and Raúl de la Fuente Marcos, together with the researcher Sverre J. Aarseth of the University of Cambridge (United Kingdom), have analyzed for the first time the nearly 340 objects of the solar system with hyperbolic orbits (very...

Our sun has had close encounters with other stars in the past, and it’s due for a dangerously close one in the not-so-distant future. Every 50,000 years or so, a nomadic star passes near our solar system. Most brush by without incident. But, every once in a while, one comes so close that it gains a prominent place in Earth’s night sky, as well as knocks distant comets loose from their orbits. The most famous of these stellar interlopers is called Scholz’s Star. This small binary star system was discovered in 2013. Its orbital path indicated that, about 70,000 years...

Rather, the comet's behavior is probably typical for comets making their first trip toward the sun — we just haven't been able to observe it before. "What makes this comet special is that it was discovered early," Jewitt said. "We've been able to follow the way the comet changes with distance from the sun over a much larger range than has ever been done before." Comet K2 comes from even farther away than the Kuiper Belt, Jewitt said. The comet's original home was most likely the Oort Cloud, the repository of comets and planetary fragments that extends from 2,000 to...

The orbits of long-period comets suggest a star passed by our Sun and caused some havoc we're still seeing. Hale-Bopp, the Great Comet of 1997, is a very famous long-period comet. Image Credit: ESO/E. Slawik ================================================================= The closest star to the Sun is Proxima Centauri, about 4.2 light-years away. This has not always been the case, as all stars in the galaxies move about. Observations suggest that just 2.5 million years ago, there was a star that passed very close to the Solar System, and this passage might still have consequences we can see today. Data from the ESA Gaia...

The search for a ninth planet in our solar system could reach a turning point as soon as this year, according to a planetary scientist involved in the hunt for a mysterious object believed to be lurking in the outer reaches of the Solar System. For the past decade, astronomers around the world have been searching for evidence of another resident in our planetary neighborhood. As far back as 2016, there were already hints that something might be out there, given the odd orbits of distant objects like Sedna, discovered in 2003. Now, two astronomers—California Institute of Technology (Caltech) researchers...

Astronomers have uncovered a stunning twist in the mysteries of Uranus’ moons. Image: NASA, ESA, STScI, Christian Soto (STScI); Image Processing: Joseph DePasquale (STScI) | The Daily Galaxy --Great Discoveries Channel ================================================================== A groundbreaking new study has uncovered surprising revelations about the moons of Uranus, challenging existing theories of how these moons interact with the planet’s magnetic field. Researchers, armed with the advanced ultraviolet instruments of the Hubble Space Telescope, have found that the “dark sides” of Uranus’ largest moons—previously thought to be on their trailing hemispheres—are actually on the opposite sides. The new findings, presented at the 246th American...

Is Planet Nine real? A new study may have just found the strongest clue yet. By analyzing decades-old infrared data from IRAS and AKARI satellites, scientists have spotted a slow-moving object in the outer Solar System—exactly where Planet Nine is predicted to be. If confirmed, it would be the first new planet discovered in over 170 years. Dive into the science, the discovery, and what it means for our cosmic future in this exciting episode. Planet Nine: First Real Clue After Decades of Searching | 9:37 NASASpaceNews | 511K subscribers | 3,717 views | May 2, 2025 Chapters: 00:00 Introduction...

The mystery dates back to Voyager 2's visit to Uranus in January 1986, far before the probe left the solar system in 2018. The spacecraft found that Uranus' magnetic field is asymmetric and tilted roughly 60° away from its spin axis. Additionally, Voyager 2 found that the radiation belts of Uranus, consisting of particles trapped by this magnetic field, are about 100 times weaker than predicted. "It has a magnetic field like no other in the solar system. Most planets that have strong intrinsic magnetic fields, like Earth, Jupiter and Saturn. They have a very 'traditional' magnetic field shape, which...

In the far reaches of our solar system beyond the orbit of Neptune, a mysterious and yet-unseen world may be lurking in the darkness. Dubbed “Planet 9,” this hypothetical celestial body has been the subject of intense scientific debate and speculation since its existence was first proposed in 2016. Now, a new study published to the arXiv pre-print service by a team from the California Institute of Technology, Université Côte d’Azur, and Southwest Research Institute has provided compelling evidence supporting the presence of this enigmatic planet. The origin of the Planet 9 hypothesis stems from the peculiar alignments in the...

Long-term expansion of Mediterranean forests and increase in precipitation as well as an enhanced East Asian summer monsoon associated with the increase and northward migration of the Atlantic moisture source. Paradoxically, the glacial was warmer and wetter than the preceding interglacial. Credit: André Bahr Approximately 700,000 years ago, a "warm ice age" permanently changed the climate cycles on Earth. Contemporaneous with this exceptionally warm and moist period, the polar glaciers greatly expanded. A European research team including Earth scientists from Heidelberg University used recently acquired geological data in combination with computer simulations to identify this seemingly paradoxical connection.

Artist’s impression of how astronomical forces affect the Earth’s motion, climate, and ice sheets. Credit: NAOJ A team of researchers, including climatologists and an astronomer, has utilized an enhanced computer model to recreate the ice age cycles that occurred between 1.6 and 1.2 million years ago. The findings indicate that the glacial periods were primarily influenced by astronomical forces in quite a different way than it works in the present day. This information will contribute to a more comprehensive understanding of ice sheets and the Earth’s climate throughout the past, present, and future. The slow, gradual changes in the Earth’s...

Our Solar System is a pretty busy place. There are millions of objects moving around – everything from planets, to moons, to comets, and asteroids. And each year we're discovering more and more objects (usually small asteroids or speedy comets) that call the Solar System home. Astronomers had found all eight of the main planets by 1846. But that doesn't stop us from looking for more. In the past 100 years, we've found smaller distant bodies we call dwarf planets, which is what we now classify Pluto as. The discovery of some of these dwarf planets has given us reason...

As part of the VLA nascent disk and multiplicity survey (VANDAM for short), the researchers mapped the radio waves leaking out of a dense cocoon of dust about 600 light-years away that contained a whole nursery of young stars. The VANDAM survey allowed for a census of stars younger than half a million years old called Class 0 stars – mere babies in star terms – and stars a little older between 500,000 years and 1 million years, called Class 1. Combined with data on the shapes of the surrounding cloud of dust, the scientists found 45 lonely stars, 19...

Highlighted by astronomers at the University of Rochester and the European Southern Observatory, the star — nicknamed “Scholz’s star” — has a very low tangential velocity in the sky, but it has been clocked traveling at a breakneck speed away from us. In other words, from our perspective, Scholz’s star is fleeing the scene of a collision with us. “Most stars this nearby show much larger tangential motion,” said Eric Mamajek, of the University of Rochester. “The small tangential motion and proximity initially indicated that the star was most likely either moving towards a future close encounter with the solar...

The origins of Comet 96P/Machholz (96P) have puzzled scientists for decades since its discovery. It is a four-mile-wide “sungrazer” object with a host of weird properties that suggest it may be an interloper from another star system. For instance, 96P’s composition is extremely unique and its orbit is highly tilted, causing it to pass closer to the Sun than almost any other comet. These features, among others, suggest that 96P may have been rerouted into our solar system by a chance encounter with Jupiter after its voyage across interstellar space. In an ironic twist, however, the comet's interactions with Jupiter...

an image of uranus taken using the keck observatory. The planet appears to glow blue against the darkness, with thin, gossamer rings wrapped vertically around its middle Uranus as imaged by the Keck Observatory. (Lawrence Sromovsky, University of Wisconsin-Madison/W.W. Keck Observatory) Uranus marches to the beat of its own weird little drum. Although it shares many similarities with our Solar System's other ice giant, Neptune, it has a bunch of quirks that are all its own. And one of these is impossible to miss: Its rotational axis is so skewed it may as well be lying down. That's a whopping...

If Uranus was not tilted in one blow, as is commonly thought, but rather was bumped in at least two smaller collisions, there is a much higher probability of seeing its moons orbit in the direction we observe. By European Planetary Science Congress, AAS Division for Planetary Science — Uranus’ highly tilted axis makes it something of an oddball in our solar system. The accepted wisdom is that Uranus was knocked on its side by a single large impact, but new research rewrites our theories of how Uranus became so tilted and also solves fresh mysteries about the position and...

Neptune's own existence was a puzzle until recently. The dusty cloud that gave birth to the planets probably thinned out further from the sun. With building material so scarce, it is hard to understand how Uranus and Neptune, the two outermost planets, managed to get so big. But what if they formed closer in? In 2005, a team of scientists proposed that the giant planets shifted positions in an early upheaval (New Scientist, 25 November 2006, p 40). In this scenario, Uranus and Neptune formed much closer to the sun and migrated outwards, possibly swapping places in the process. That...

What could happen to the earth in the distant future if we don't have the sun to keep us warm anymore or allow plants to grow. 9 minutes 45 seconds long.