Latest news with #DECaLS
Yahoo
3 days ago
- General
- Yahoo
Search for 'Planet Nine' Yields Unexpected Discovery
Astronomers have long been on the hunt for "Planet Nine," a hypothetical planet that lies within our solar system just beyond Neptune. Scientific evidence has alternately pointed to and against the existence of such a planet, but the search is still on, stoked by the 2006 demotion of Pluto to "dwarf planet." This time, scouring the cosmos may have yielded a concrete result—it's just not the kind astronomers were hoping for. A small team of researchers at the Institute for Advanced Study and Princeton University spent half a year sifting through data from the Victor M. Blanco Telescope's Dark Energy Camera Legacy Survey (DECaLS). Gathered in 2019 by the telescope's Dark Energy Camera, or DECam, the archive consists of wild-field optical imaging data from the green, red, and z bands. Though these filters make it possible to search for distant space objects via photometric redshift, no one (to the researchers' knowledge) had looked for Planet Nine in the DECaLS dataset before. According to a preprint paper that has not yet undergone peer review, the researchers found a dwarf planet candidate they've since dubbed 2017 OF201. With an estimated diameter of approximately 700 kilometers (435 miles), the object is just big enough to classify as a dwarf planet. The International Astronomical Union's Minor Planet Center announced the finding this month. This illustration shows just how wide 2017 OF201's orbit is, compared with the orbits of solar system planets. Credit: Jiaxuan Li, Sihao Cheng But the team is lucky they found 2017 OF201 at all: Only 0.5% of its wide, elliptical orbit comes close enough to Earth for Blanco to detect. At its farthest point from the Sun (aphelion), the object is more than 1,600 times farther away than Earth, making a complete orbit 25,000 years long. "This limited visibility window strongly suggests that a substantial population of similar objects—with large sizes, wide orbits, and high eccentricities—should exist but be difficult to detect due to their extremely large distance," the paper reads. The orbit of 2017 OF201 is also strange because it appears to contradict a common hypothesis about Planet Nine. The hypothetical planet's gravity is thought to shepherd trans-Neptunian objects into a cluster of sorts, but 2017 OF201 resists such clustering. What this means within the broader search for Planet Nine will likely be determined by Chile's Vera Rubin Observatory, which is expected to go online later this year.
Yahoo
09-02-2025
- Science
- Yahoo
Astronomers found a monstrous jet powering through the early universe
Scientists have found a quasar spewing a gigantic radio jet in space at a time in the early universe when such objects are nearly impossible to find. Quasars, a portmanteau for "quasi-stellar objects," are blindingly bright galaxy cores. Through powerful telescopes, these distant objects can look like stars, but they're the resulting light from feasting supermassive black holes. The jet, sprawling at least 200,000 light-years, double the span of the Milky Way, emerges from the J1601+3102 quasar, born less than 1.2 billion years after the Big Bang. Though a billion years later may not seem like the early days, that period occurred when the universe was only nine percent of its current age of 13.8 billion — making it a mere toddler. "It's only because this object is so extreme that we can observe it from Earth, even though it's really far away," said Anniek Gloudemans, a research fellow at the federally funded NOIRLab, in a statement. SEE ALSO: Scientists found a colossal black hole near the dawn of time The J1601+3102 quasar's radio jet was first discovered by the Low Frequency Array Telescope. Credit: LOFAR / DECaLS / DESI Legacy Imaging Surveys / LBNL / DOE / CTIO / NOIRLab / NSF / AURA Finding this radio jet, first discovered by the European Low Frequency Array Telescope, is an enormous achievement. Follow-up observations ensued in near-infrared light with the Gemini North Telescope and in visible light with Hobby Eberly Telescope. A research team has characterized the object in a new paper published in The Astrophysical Journal Letters. These jets become elusive the farther back in time astronomers try to look because of the so-called cosmic microwave background. The ancient radiation, the earliest fossil of light from 380,000 years after the Big Bang, tends to swamp out more subtle signals. Although quasars are technically difficult to find in the early universe, the nearest quasars to Earth are still several hundred million light-years away. That quasars aren't found closer to home is a clue they are ancient relics. Scientists continue to hunt for them because they provide insight into the evolution of galaxies and the universe as a whole. Black holes in general are some of the most inscrutable things in space. Astronomers believe these invisible giants skulk at the center of virtually all galaxies. Falling into one is an automatic death sentence. Any cosmic stuff that wanders too close reaches a point of no return. But scientists have observed something weird at the edge of black holes' accretion disks, the rings of rapidly spinning material around the holes, like the swirl of water around a bathtub drain: A tiny amount of the material can suddenly get rerouted. When this happens, high-energy particles get flung outward as a pair of jets, blasting in opposite directions, though astronomers haven't quite figured out how they work. It's also still a mystery when exactly in cosmic history the universe started making them. Despite this jet's length, it's a pipsqueak compared to others scientists have discovered in later eras. Porphyrion, observed 6.3 billion years after the Big Bang, has a 23 million light-year-long jet. The J1601+3102 quasar is also of modest size, just 450 million times more massive than the sun. Quasars are sometimes known to tip scales at billions of times heavier than the sun. "Interestingly, the quasar powering this massive radio jet does not have an extreme black hole mass compared to other quasars," Gloudemans said. "This seems to indicate that you don't necessarily need an exceptionally massive black hole or accretion rate to generate such powerful jets in the early universe."
