James Webb Space Telescope discovers an alien planetary system's icy edge
At long last, particles of water–ice have been discovered in the frozen Kuiper Belt of another star. The discovery, made by the James Webb Space Telescope, is a major step forward in filling in gaps in our understanding of how exoplanets develop.
Like the Kuiper Belt in our solar system, this extraterrestrial debris disk is likely filled with comets, dwarf planets and a lot of water-ice particles chipped off larger bodies as the result of collisions. The debris disk, also like our Kuiper Belt, is made up of remnants of a larger disk that once encircled the star — called HD 181327 — and probably gave birth to planets. To be clear, however, no planets in the region have been detected thus far.
Because water is one of the most common molecules in the universe, its presence in HD 181327's debris disk is not a surprise. Indeed, exocomets have been detected around other stars; in our solar system, comets come from the frigid, icy Kuiper Belt and the Oort Cloud, so exocomets must originate from somewhere similar.
However, while debris disks around other stars have been known about and imaged ever since the Infrared Astronomy Satellite (IRAS) found debris disks around two nearby stars (Vega and beta Pictoris) a while back, we've not had an instrument able to detect water-ice within them until now.
Using the James Webb Space Telescope (JWST) and its Near-Infrared Spectrometer (NIRSpec), astronomers led by Chen Xie of Johns Hopkins University in the United States probed the debris disk around HD 181327. The star and its debris disk have previously been well-studied. Located 155.6 light-years away, they are just 18.5 million years old. This is extremely young compared to our sun's age of 4.6 billion years. The star is an F-type, meaning it's a little hotter and slightly more massive than our sun.
NIRSpec detected the signature water in HD 181327's spectrum, principally at a wavelength of 3 microns (millionths of a meter), with a peak coming at 3.1 microns. This spike in the spectrum, referred to as a "Fresnel peak," is caused by the refraction of light by water-ice particles that are just millimeters in size. This is similar in size to the icy particles in Saturn's rings, for example, and the ice is likely frozen around motes of interplanetary dust.
"Basically, we detected a water–ice reservoir," Xie told Space.com.
This water–ice reservoir could be instrumental in the development of any planetary system that might exist around HD 181327. Gas giant planets, for example, form beyond a boundary called the snow line, which is the distance from a star where temperatures are cold enough for planet-forming material to contain water-ice. Water-ice helps material stick together in a giant kind of mush that can form the basis of a large, rocky planetary core that can then pull in gas to form the distended atmosphere of a giant planet.
The water on terrestrial planets such as Earth also likely was delivered by asteroids and/or comets that formed beyond the snow line and are rich in water-ice. Therefore, the discovery of water-ice in HD 181327's debris disk means the materials are present there to aid in the development of any planets orbiting the star, although at this time no planets have yet been detected in the system.
"The presence of a water-ice reservoir in the planetesimal belt around HD 181327 provides the potential to deliver water to nearby planets," said Xie. "But we don't know how much water-ice could eventually be delivered to the planets in the system."
It's tempting to make comparisons between our Kuiper Belt and HD 181327's debris disk. Xie warns about being too literal in the comparison, though, because there are significant gaps in our knowledge of both icy belts and how they relate to each other. Nevertheless, we can draw some general conclusions.
"The presence of water-ice in a debris disk around such a young star does suggest that icy planetesimals can form relatively quickly, so it's possible that icy bodies in our own Kuiper Belt could have formed early in the cold outer regions of the solar system," he said. Their early existence could have then helped in the development of the solar system's planets.
However, the planet-forming disk around HD 181327 has now dissipated, and any planets that are present will have already formed. Furthermore, the JWST's observations show how the inner region of the debris disk is being eroded by the star's ultraviolet light. The strength of the spectral line for water-ice at the inner edge of the debris disk, 80 to 90 astronomical units (meaning 80 to 90 times Earth's distance from the sun), suggests water-ice makes up just 0.1% of the total mass in that part of the disk. Farther out, between 90 and 105 astronomical units, the water-ice mass fraction rises to 7.5%, and between 105 and 120 astronomical units it peaks at 21%, out where it is coldest. Coincidentally, the Fresnel peak is found between 90 and 105 astronomical units.
So, what's going on? Ultraviolet light from the star is able to vaporize the water-ice, but something seems to be replenishing it — otherwise, the water-ice in the debris disk would have eroded away by now.
This replenishment likely comes from collisions between dwarf planets, cometary nuclei, micrometeoroids and other flotsam and jetsam lurking in the dark of the debris disk. Each impact sputters more dust and ice grains into space, and each large impact sends a shower of fragments spinning away. If there's enough dust present, it could also shield water-ice from the star's ultraviolet light. Dust that has been detected already includes grains of olivine and iron sulfide.
Related Stories:
— 2nd Kuiper Belt? Our solar system may be much larger than thought
— Hubble Telescope discovers a new '3-body problem' puzzle among Kuiper Belt asteroids (video)
— New JWST observations of 'trans-Neptunian objects' could help reveal our solar system's past
Meanwhile, the Atacama Large Millimeter/submillimeter Array (ALMA), which is a radio telescope in Chile, has detected carbon monoxide in the debris disk, which could also have been released into space by collisions between icy bodies. In addition, the JWST's NIRSpec found tentative evidence for the presence of carbon dioxide in the region of the disk between 105 and 120 astronomical units from the star, although this still needs to be confirmed. A second spectral line for water-ice, at 4.5 microns, was also detected by the JWST in the 105 to 120 astronomical-unit region, indicating this outer part of the debris disk might be the most rich in volatiles: gases with low evaporation points.
Now that the JWST has demonstrated that it can detect water-ice in exoplanetary systems, we can expect more widespread discoveries in the future. Indeed, Xie and his team are already working on it.
"Besides HD 181327, we have also observed other systems with the JWST and NIRSPec," he said. "We're currently working on publishing those data, so stay tuned!"
The discovery of water-ice around HD 181327 was published on May 14 in the journal Nature.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
3 hours ago
- Yahoo
Scientists hit quantum computer error rate of 0.000015% — a world record achievement that could lead to smaller and faster machines
When you buy through links on our articles, Future and its syndication partners may earn a commission. Scientists have achieved the lowest quantum computing error rate ever recorded — an important step in solving the fundamental challenges on the way to practical, utility-scale quantum computers. In research published June 12 in the journal APS Physical Review Letters, the scientists demonstrated a quantum error rate of 0.000015%, which equates to one error per 6.7 million operations. This achievement represents an improvement of nearly an order of magnitude in both fidelity and speed over the previous record of approximately one error for every 1 million operations — achieved by the same team in 2014. The prevalence of errors, or "noise," in quantum operations can render a quantum computer's outputs useless. This noise comes from a variety of sources, including imperfections in the control methods (essentially, problems with the computer's architecture and algorithms) and the laws of physics. That's why considerable efforts have gone into quantum error correction. While errors related to natural law, such as decoherence (the natural decay of the quantum state) and leakage (the qubit state leaking out of the computational subspace), can be reduced only within those laws, the team's progress was achieved by reducing the noise generated by the computer's architecture and control methods to almost zero. Related: Scientists make 'magic state' breakthrough after 20 years — without it, quantum computers can never be truly useful "By drastically reducing the chance of error, this work significantly reduces the infrastructure required for error correction, opening the way for future quantum computers to be smaller, faster, and more efficient," Molly Smith, a graduate student in physics at the University of Oxford and co-lead author of the study, said in a statement. "Precise control of qubits will also be useful for other quantum technologies such as clocks and quantum sensors." Record-low quantum computing error rates The quantum computer used in the team's experiment relied on a bespoke platform that eschews the more common architecture that uses photons as qubits — the quantum equivalent of computer bits — for qubits made of "trapped ions." The study was also conducted at room temperature, which the researchers said simplifies the setup required to integrate this technology into a working quantum computer. Whereas most quantum systems either deploy superconducting circuits that rely on "quantum dots" or employ the use of lasers — often called "optical tweezers" — to hold a single photon in place for operation as a qubit, the team used microwaves to trap a series of calcium-43 ions in place. With this approach, the ions are placed into a hyperfine "atomic clock" state. According to the study, this technique allowed the researchers to create more "quantum gates," which are analogous to the number of 'quantum operations' a computer can perform, with greater precision than the photon-based methods allowed. Once the ions were placed into a hyperfine atomic clock state, the researchers calibrated the ions via an automated control procedure that regularly corrected them for amplitude and frequency drift caused by the microwave control method. In other words, the researchers developed an algorithm to detect and correct the noise produced by the microwaves used to trap the ions. By removing this noise, the team could then conduct quantum operations with their system at or near the lowest error rate physically possible. Using this method, it is now possible to develop quantum computers that are capable of conducting single-gate operations (those conducted with a single qubit gate as opposed to a gate requiring multiple qubits) with nearly zero errors at large scales. This could lead to more efficient quantum computers in general and, per the study, achieves a new state-of-the-art single-qubit gate error and the breakdown of all known sources of error, thus accounting for most errors produced in single-gate operations. This means engineers who build quantum computers with the trapped-ion architecture and developers who create the algorithms that run on them won't have to dedicate as many qubits to the sole purpose of error correction. RELATED STORIES —'The science is solved': IBM to build monster 10,000-qubit quantum computer by 2029 —Scientists forge path to the first million-qubit processor for quantum computers after 'decade in the making' breakthrough —'Quantum AI' algorithms already outpace the fastest supercomputers, study says By reducing the error, the new method reduces the number of qubits required and the cost and size of the quantum computer itself, the researchers said in the statement. This isn't a panacea for the industry, however, as many quantum algorithms require multigate qubits functioning alongside or formed from single-gate qubits to perform computations beyond rudimentary functions. The error rate in two-qubit gate functions is still roughly 1 in 2,000. While this study represents an important step toward practical, utility-scale quantum computing, it doesn't address all of the "noise" problems inherent in complex multigate qubit systems.
Yahoo
7 hours ago
- Yahoo
Rogue black hole found terrorizing unfortunate star in distant galaxy
When you buy through links on our articles, Future and its syndication partners may earn a commission. A rogue, middle-mass black hole has been spotted disrupting an orbiting star in the halo of a distant galaxy, and it's all thanks to the observing powers of the Hubble Space Telescope and Chandra X-ray Observatory. However, exactly what the black hole is doing to the star remains in question as there are conflicting X-ray measurements. Black holes come in different size classes. At the smaller end of the scale are the stellar-mass black holes born in the ashes of supernova explosions. At the top end of the scale are the supermassive black holes, which can grow to have many millions or billions of times the mass of our sun, lurking in the hearts of galaxies. In between those categories are intermediate-mass black holes (IMBH), which have mass ranging from hundreds up to 100,000 solar masses, or thereabouts. "They represent a crucial missing link in black hole evolution between stellar mass and supermassive black holes," Yi-Chi Chang of the National Tsing Hua University in Hsinchu, Taiwan said in a statement. The problem is that intermediate-mass black holes are hard to find, partly because they tend not to be as active as supermassive black holes or as obvious as a stellar-mass black hole when its progenitor star goes supernova. However, occasionally, an IMBH will spark to life when it instigates a tidal disruption event. This happens when a star or gas cloud gets too close to the black hole and gravitational tidal forces rip the star or gas cloud apart, producing bursts of X-rays. "X-ray sources with such extreme luminosity are rare outside galaxy nuclei and can serve as a key probe for identifying elusive IMBHs," said Chang. In 2009, Chandra spotted anomalous X-rays originating from a region 40,000 light-years from the center of a giant elliptical galaxy called NGC 6099, which lies 453 million light-years from us. This bright new X-ray source was called HLX-1, and its X-ray spectrum indicated that the source of the X-rays was 5.4 million degrees Fahrenheit (3 million degrees Celsius), a temperature consistent with the violence of a tidal disruption event. But what followed was unusual. The X-ray emissions reached a peak brightness in 2012 when observed by the European Space Agency's XMM-Newton X-ray space telescope. When XMM-Newton took another look in 2023, it found the X-ray luminosity had substantially dwindled. In the meantime, the Canada–France Hawaii Telescope had identified an optical counterpart for the X-ray emission, one that was subsequently confirmed by Hubble. There are two possible explanations for what happened. The first is that Hubble's spectrum of the object shows a tight, small cluster of stars swarming around the black hole. The black hole might have once been at the core of a dwarf galaxy that was whittled down — unwrapped like a Christmas present — by the gravitational tides of the larger NGC 6099. This process would have stolen away all the dwarf galaxy's stars to leave behind a free-floating black hole with just a small, tight grouping of stars left to keep it company. But the upshot of this is that the cluster of stars is like a stellar pantry to which the black hole occasionally goes to feast. It seems certain that a tidal disruption event involving one of these stars is what Chandra and Hubble have witnessed, but was the star completely destroyed? One possibility is that the star is on a highly elliptical orbit, and at its perihelion (closest point to the black hole) some of the star's mass is ripped away — but the star managed to survive for another day. This would potentially explain the X-ray light curve: The emission from 2009 was as the star was nearing perihelion, while the peak in 2012 was during perihelion, and the latest measurements in 2023 would be when the star was farthest from the black hole and not feeling its effects so much. We might then expect another outburst of X-rays during its next perihelion, whenever that might be. However, there's an alternative hypothesis: The star may have been stripped apart a piece at a time, forming a stream of material around the black hole. When Chandra first detected the X-ray emission from the tidal disruption event, this stream was just beginning to wrap back on itself, the self-intersection giving rise to shock-heating that produced X-rays. Then, the 2012 measurements would have been of a fully-fledged hot accretion disk of gas, the star by now completely ripped apart. The material within this disk would have spiraled into the black hole's maw, thus depleting the disk, which would explain why it is much less luminous in X-rays in 2023. Picking out the correct scenario apart will require further surveillance. "If the IMBH is eating a star, how long does it take to swallow the star's gas? In 2009, HLX-1 was fairly bright. Then, in 2012, it was about 100 times brighter, and then it went down again," Roberto Soria of the Italian National Institute for Astrophysics (INAF), who is a co-author of a new study describing the observations of HLX-1, said in the statement. "So now we need to wait and see if it's flaring multiple times, or if there was a beginning, a peak, and now it's just going to go down all the way until it disappears." Making new observations of an IMBH such as HLX-1 is key to better understanding the role they play in the black hole ecosystem. One model suggests that supermassive black holes might form and grow through the merger of many IMBH, but nobody knows how common intermediate-mass black holes are in the universe. "So if we are lucky, we're going to find more free-floating black holes suddenly becoming X-ray bright because of a tidal disruption event," said Soria. "If we can do a statistical study, this will tell us how many of these IMBHs there are, how often they disrupt a star, [and] how bigger galaxies have grown by assembling smaller galaxies." RELATED STORIES — Rogue black hole spotted on its own for the first time — Astronomers may have discovered the closest black holes to Earth — Hubble Telescope sees wandering black hole slurping up stellar spaghetti Alas, Chandra, XMM-Newton and Hubble all have small fields of view, meaning that they only see small patches of the sky. Because we don't know where the next tidal disruption event might take place, the chances of our space telescopes looking in the right place at the right time are slim. In essence, Chandra got lucky back in 2009. Fortunately, help is now on hand. The Vera C. Rubin Observatory comes fully online later this year to begin a 10-year all-sky survey, and spotting the flares of tidal disruption events will be a piece of cake for it. Once it finds such an event, Hubble and Chandra will know where to look and can follow up on it. IMBHs have remained mostly hidden for now, but their time in the shadows is coming to an end. The findings were published on April 11 in The Astrophysical Journal.
Yahoo
8 hours ago
- Yahoo
Scientists gave mice flu vaccines by flossing their tiny teeth — and it worked
When you buy through links on our articles, Future and its syndication partners may earn a commission. Scientists have developed a new, needle-free way to deliver vaccines: through the gumline. In a new proof-of-concept study, researchers successfully vaccinated mice against influenza by cleaning their teeth with dental floss coated with inactive flu viruses. Most vaccines are administered using a needle, an approach that has its drawbacks. For example, apprehension about pain from the injection and needle phobias can deter people from getting vaccinated. Additionally, injections require more medical expertise to administer than needle-free options, like mouth drops or nasal sprays, and are more challenging to store and distribute. But a floss-based vaccine could eliminate the pain and logistical challenges surrounding injections and "even be distributed through the postal mail," the researchers behind the development wrote in their study, published July 22 in the journal Nature Biomedical Engineering. Such a vaccine could potentially be deployed in "resource-limited settings with minimal training," they added, and be especially helpful in active outbreaks when vaccine coverage needs to be boosted quickly. Previous studies have shown that vaccinations delivered in the cheek or under the tongue trigger satisfactory immune responses. But it can be difficult to deliver adequate doses of these vaccines through mucosal tissues in the mouth — the lining that acts as a barrier between our body and the environment. Related: Acne vaccine: Experimental shot for common skin condition reaches clinical trials. Here's what you need to know. The researchers behind the vaccine floss found a creative solution: Researchers focusing on gum disease have found particular areas in the mouth that are very permeable, meaning molecules are easily absorbed by the tissue. One of these areas is called the junctional epithelium (JE). The JE is found on the tissue between teeth, at the spot where the tooth's surface meets the gum line. By secreting different molecules, the JE detects and defends against pathogens that try to get in through the gums. The study researchers thought that the JE's ability to allow molecules through and to stimulate an immune response made it a potential candidate for a vaccine site. To reach it, they needed something that could get into that small crevice between tooth and gum. So, they went out and bought some dental floss. To explore this concept, the researchers tested their hypothesis in mice. Once they'd figured out how to floss a mouse's teeth — turns out, it's a two-person job — they set up a flossing schedule to expose 50 mice to an inactive flu virus. Killed, or "inactivated" viruses cannot cause infection and are a common component of vaccines; they're used to immunize humans against diseases such as hepatitis A and polio, for example, and are found in some types of flu shot. One group of mice had their teeth flossed with the virus-coated floss three times, with two weeks between each dose. Then, a month after their final dose, they were exposed to an active flu virus. All survived, while a comparison group of mice that was left unvaccinated all died. Further testing found that the mice that had been vaccinated via the floss had a strong immune response, producing ample antibodies and many immune cells. This immune defense was found throughout the body — known as systemic immunity — and in their saliva and feces. "The floss-based vaccination induced both systemic and mucosal immunity, while conventional intramuscular shots largely stimulate systemic immunity," first study author Rohan Ingrole, a chemical engineer at Texas Tech University, told Live Science in an email. "Mucosal immunity is important because most of the pathogens enter through the mucosal routes," he emphasized. In theory, vaccine floss could thus have an edge over syringe vaccines by triggering this additional protection, but the team would like to directly compare the two methods in the future to validate this idea. RELATED STORIES —2-in-1 COVID-flu vaccine looks promising in trial — but experts say approval may be delayed —At-home flu vaccine approved by FDA — what to know —What are mRNA vaccines, and how do they work? Next, the researchers wanted to know if flossing could transfer compounds to the JE in humans. As an early test, they used a fluorescent marker and blue food coloring to coat a dental pick and had healthy volunteers floss their teeth with it. Photographs confirmed that a fair amount of the dye was transferred to the space between their teeth and gum, though just over 41% was left on the floss. The next step, the researchers said, is to translate the research to larger animals, which "can then lay the foundation for human testing in the near future," senior study author Harvinder Gill, a bioengineer at North Carolina State University, told Live Science in an email. This article is for informational purposes only and is not meant to offer medical advice.
