Close-up image of silicon microchannels. In microDMFC fuel cells, methanol and air circulate in microscopic microchannels etched in silicon wafers, as shown here. Image credit: Steve Arscott. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. One alternative to lithium ion batteries is fuel cells, due to their advantage of a high energy density – potentially, sixteen times higher than lithium ion batteries. Although researchers have been working on fuel cells for several years, they still face several challenges. In a recent study, a team of researchers has developed micro-sized direct methanol fuel cells (microDMFC) that achieve significantly improved fuel efficiency and maintain a good power density while operating at room temperature. The energy density (measured in watt-hours per liter) of the new fuel cells is 385 Wh/L, which is superior to lithium ions batteries’ value of 270 Wh/L.The research, led by Dr. Steve Arscott at the Institute of Electronics, Microelectronics and Nanotechnology (IEMN) in France, working in collaboration with SHARP Corporation in Nara, Japan, is published in a recent issue of the Journal of Micromechanics and Microengineering, and a second study has been accepted to the Journal of Power Sources.Both studies use methanol fuel cells, in which methanol is the fuel and serves as the anode, while air is the oxidant and serves as the cathode. The methanol and air circulate through the fuel cell in microscopic microchannels etched in silicon wafers. When the methanol and air react in the presence of an electrolyte, electricity is produced.In their second study, the researchers inserted a novel macroporous layer into the silicon-based microfuel cell. This design helped them improve the fuel efficiency from an already high 20 percent in their first study to 75 percent, while operating at room temperature. At this efficiency, the cells had a power density of 4.3 mW/cm2 and 9.25 mW/cm2 in the two respective studies. By adding a little bit more fuel, the researchers could increase the cells’ power density to 12.7 mW/cm2, although the efficiency then dropped to 20 percent (numbers are from the second study).While previous fuel cells have achieved higher power density (up to 47.2 mW/cm2, by Yen et al), they haven’t operated at room temperature, which is absolutely essential for a commercial product. Part of the reason that the new fuel cell achieves unprecedented fuel efficiency is because it uses a small amount of fuel (as little as 1.38 microliters per minute, or 550 nanoliters per minute, in the first and second study, respectively). By using a minimal amount of fuel, it’s possible to eliminate components such as pumps, which in turn would lower the cell’s energy consumption. However, as the researchers demonstrated, a minimum amount of fuel is necessary to maintain a steady fuel concentration across the cell to achieve maximum efficiency.From the design perspective, the key to achieving high power density at room temperature is reducing both the fuel cell size and microchannel cross-sections. These modifications resulted in overall device miniaturization to a size of 0.18 cm2, with a thickness of 0.17 cm, corresponding to a tiny cell volume of 0.03 cm3 and a weight of about 110 milligrams. According to Arscott, these microcells are the smallest and lightest high-performance microDMFC working at room temperature to date.Despite these improvements, challenges still remain, as Arscott highlighted.“The biggest challenges facing micro fuel cells are: (i) high-performance room-temperature operation, (ii) miniaturization for on-chip use, (iii) compatibility with existing system fabrication (CMOS, for example), (iv) avoidance of complicated pumps for fuel and air which use energy themselves, (v) use of an efficient silicon-based proton exchange membrane and diffusion layers (novel porous layers for example), (vi) full integration with a microchannel architecture and also (vii) fuel storage,” he told PhysOrg.com. “On the latter point, obviously the more fuel efficient the cell, the less fuel needs to be stored for a given working period.”In addition to applications in mobile consumer devices, the fuel cells could also be integrated as on-chip energy sources for autonomous MEMS and NEMS devices, as well as for sensors and actuators in silicon microelectronics, where efficient fuel use will be important. Arscott explained that different kinds of applications will require different kinds of fuel cells.“In terms of fuel cells and energy sources, one must compare like with like: on one hand, fuel cells which will be one day be used for automobiles will be large and will have to supply a high power and have an energy density for a long journey,” he said. “On the other hand, micro fuel cells for a new generation of autonomous MEMS/NEMS-based sensors and actuators will require compact, on-chip, very efficient, high energy density energy sources which can supply micro and milliwatts for a long time. In the latter case, the energy required will be to drive the sensor and to communicate with the environment (for example, send a signal which says ‘forest fire here!’). I don’t think there will be one dominant fuel cell for all applications, but there is likely to be one dominant fuel cell per application, for example, the hydrogen cell for cars or the methanol cell for portable and autonomous micro/nanosystems.”Based on the progress of fuel cell research, fuel cells may begin widely replacing lithium ion batteries in consumer devices in the near future. “From a research point of view, prediction is very hard,” Arscott said. “One can see fuel cells powering consumer electronics (iPod, Blackberry, etc.) in the next few years; one can see fuel cells powering automobiles in the next 20 years (or not, if we find huge resources of petrol in the Arctic, for example). The popularity and success of something is based on many factors – for example, cost (energy/dollar), availability, performance and the lawmakers. For instance, a ban on existing polluting batteries that contain heavy metals would favor fuel cells.“One thing is sure,” he added. “Like everyone, I think that energy is about to become very important and, as Mark Twain (of who I’m a big fan) said, ‘What is a government without energy? And what is a man without energy? Nothing, nothing at all…’”More information: Kamitani, Ai; Morishita, Satoshi; Kotaki, Hiroshi; and Arscott, Steve. “Miniaturized microDMFC using silicon microsystems techniques: performances at low fuel flow rates.” J. Micromech. Microeng. 18 (2008) 125019 (9pp)Kamitani, Ai; Morishita, Satoshi; Kotaki, Hiroshi; and Arscott, Steve. “Improved fuel use efficiency in microchannel based DMFC using a hydrophilic macroporous layer.” J. Power Sources. To be published.Copyright 2008 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. Citation: Micro Fuel Cells Get Closer to Replacing Batteries (2008, November 17) retrieved 18 August 2019 from https://phys.org/news/2008-11-micro-fuel-cells-closer-batteries.html Toyota to test solar panels for electric cars Explore further (PhysOrg.com) — Mobile electronics have the potential to offer digital luxuries beyond our imagination, but they will never get there on today’s lithium ion batteries. Power has been the weak spot in the development of more advanced mobile electronics, and the need for power will become even more important as devices feature more energy-sapping applications.
Universe offers ‘eternal feast,’ cosmologist says (PhysOrg.com) — Over the past few decades, the idea that our universe could be one of many alternate universes within a giant multiverse has grown from a sci-fi fantasy into a legitimate theoretical possibility. Several theories of physics and astronomy have hypothesized the existence of a multiverse made of many parallel universes. One obvious question that arises, then, is exactly how many of these parallel universes might there be. The strongest limit on the number of possible universes is the human ability to distinguish between different universes. Credit: Linde and Vanchurin. Explore further Citation: Physicists Calculate Number of Parallel Universes (2009, October 16) retrieved 18 August 2019 from https://phys.org/news/2009-10-physicists-parallel-universes.html In a new study, Stanford physicists Andrei Linde and Vitaly Vanchurin have calculated the number of all possible universes, coming up with an answer of 10^10^16. If that number sounds large, the scientists explain that it would have been even more humongous, except that we observers are limited in our ability to distinguish more universes; otherwise, there could be as many as 10^10^10^7 universes.To work these numbers out, Linde and Vanchurin looked back to the time shortly after the Big Bang, which they view as a quantum process that generated lots of quantum fluctuations. Then during the period of inflation, the universe grew rapidly and these quantum fluctuations were “frozen” into classical perturbations in distinct regions. Today, each of these regions could be a different universe, having its own distinct laws of low energy physics.By analyzing the mechanism (called “slow roll inflation”) that initially generated the quantum fluctuations, the scientists could estimate the number of resulting universes at 10^10^10^7 (a number which is dependent on the model they used). However, this number is limited by other factors, specifically by the limits of the human brain. Since the total amount of information that one individual can absorb in a lifetime is about 10^16 bits, which is equivalent to 10^10^16 configurations, this means that a human brain couldn’t distinguish more than 10^10^16 universes.Requiring that the human brain must be able to count the number of parallel universes may seem inappropriate, if not arrogant, but Linde and Vanchurin explain that dealing with the quantum world is different than our everyday lives in which quantum effects can be safely ignored. A crucial part of their calculation here is an investigation of quantum effects on supergalactic scales. In this kind of scenario, the state of the multiverse and observations made by an observer are correlated (similar to the Schrodinger cat experiment, where the outcome can be determined only after it is registered by a classical observer). “When we analyze the probability of the existence of a universe of a given type, we should be talking about a consistent pair: the universe and an observer who makes the rest of the universe ‘alive’ and the wave function of the rest of the universe time-dependent,” the scientists write. As the scientists explain, the calculation of the number of universes is an important step toward an even larger goal: to find the probability of living in a universe with a particular set of properties. What are the chances that we live in a world in which the laws of physics are these laws that we currently observe? Answering this question requires finding probabilities that depend on knowing about other universes, among many other challenges. • Join PhysOrg.com on Facebook!• Follow PhysOrg.com on Twitter!More information: How Many Universes are in the Multiverse? arXiv:0910.1589v1via: Technology Review© 2009 PhysOrg.com This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
Giant panda. Credit: Yange Yong (PhysOrg.com) — Scientists in China have been so successful at breeding giant pandas in captivity that they are now planning for their reintroduction to the wild with 15 years. Explore further Citation: Plan to reintroduce giant pandas to the wild (2010, December 7) retrieved 18 August 2019 from https://phys.org/news/2010-12-reintroduce-giant-pandas-wild.html The giant panda, which is classified as an endangered species, is a difficult animal to breed in captivity because the females are on heat for only 72 hours a year, and there is only a 12-24 hour window in which they can become pregnant. Another difficulty is that the males have short penises and the mating couple must adopt an exact position if the mating is to be successful, and yet the pandas in captivity appear to have little knowledge of this position.Scientists at the world’s most successful panda breeding center, the Chengdu Panda Breeding Research Centre in China have been trying to breed captive pandas for decades and have overcome many obstacles, including the short period of fertility, which necessitates them taking daily urine samples to monitor hormone levels, and close observation of panda behavior.Another challenge facing conservationists is that pandas are “turned off” by being in captivity and do not seem interested in mating. The Chengdu researchers have tried arousing male pandas by using bamboo poles laced with the scent of fertile females, but few encounters were fruitful and some ended in aggressive behavior and violence. The scientists also tried Viagra and resorted to showing sex education videos to the captive bears, both with little success.The scientists then tried artificial insemination, but this was also a challenge because of the variation in gestation, which can last anywhere from 11 weeks to 11 months, and which can be undetectable until shortly before the birth. Again, the scientists needed to closely observe the bears, and they developed a crucial form of intervention to ensure the survival of cubs, which was necessary since pandas give birth to twin cubs around 50 percent of the time, but they usually only care for one of them.The intervention is called a “twin-swapping” technique, in which an abandoned cub is immediately moved into an incubator. The scientists then surreptitiously rotate the twin cubs between mother and incubator to trick the mother into caring for both of them. Using this technique the survival rate has risen to 98 percent. By the end of 2009, 168 cubs had been raised at the center.The success of the breeding program has led conservationists to believe it will be possible to reintroduce giant pandas into the wild, and they have used some of the profits made from lending their pandas to overseas zoos to buy panda habitat in the Sichuan mountains in south west China and to begin construction of the first dedicated giant panda reintroduction facility. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. China panda baby boom aids against extinction © 2010 PhysOrg.com
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. More information: Too Damned Quiet?, Adrian Kent, arXiv:1104.0624v1 [physics.pop-ph] arxiv.org/abs/1104.0624Fermi paradox: en.wikipedia.org/wiki/Fermi_paradox How a hike led to a math ‘Eureka!’ Explore further (PhysOrg.com)—Enrico Fermi, the famous Italian physicist, once asked the question; if intelligent life has come to exist many times in our galaxy, why is there no sign of it? It’s a clearly valid point, when you consider the number of planets and solar systems that exist out there. If there are other intelligent beings out there somewhere, how come they haven’t responded to our messages? Citation: New explanation postulated for Fermi paradox (2011, April 12) retrieved 18 August 2019 from https://phys.org/news/2011-04-explanation-postulated-fermi-paradox.html © 2010 PhysOrg.com Adrian Kent, of the Perimeter Institute in Waterloo, Canada has published a paper in arXiv, somewhat humorously titled, “Too Dammed Quiet?” where he suggests the reason we haven’t heard from other life forms out there, is because maybe they are keeping quiet on purpose, to protect themselves from others that might hear their “noise” and come to investigate, and perhaps cause them harm.Kent takes the idea of Darwin’s survival of the fittest concept to a galactic level, in that he believes it’s possible that there are only so many habitable planets and if so, that would mean scarce resources, which would mean only the smartest, strongest, or most careful would survive; which would leave at least some of the aliens out there keeping a lid on things to assure their own survival; sort of like how certain species of birds on this planet freeze to avoid being noticed by predators.But, if what Kent has to say is true, that begs even more questions, such as, who are they hiding from, and why haven’t we heard anything from those pesky predators?His paper raises even more difficult questions, which of course we have no answers to, such as is it possible that the vast expanse of the universe is so great that the laws of physics will forever prevent any life forms that do crop up, from ever being able to contact one another? Or, is it conceivable, that the events that led to our existence are so rare that there really isn’t anyone else out there?Kent’s paper has no doubt some added credence due to his support of Stephen Hawking’s parallel suggestion in “Into the Universe,” the Discovery Channel documentary that made headlines all over the world last year; but as with all hypothetical suppositions, ultimately, it’s all, as Kent himself reminds us, pure speculation; at least until we hear otherwise from someone out there who can settle the matter for us, once and for all.
That technology represents a rethink in conventional solar cell design, and transforms it into a powerhouse that can yield more energy. Using the company’s proprietary Triex technology, the result is what is being called a hybrid module because it is an artful combination of three materials: crystalline silicon N-type substrates, thin-film passivation layers, and a tunneling oxide layer These materials enable the Triex module to deliver high efficiency, competitive module costs and an optimal energy harvest, the company said.”Until now, the solar industry has not had a module that optimizes both performance and cost at a ratio that creates optimal levelized cost of electricity (LCOE),” said Dr. Zheng Xu, founder and CEO.The company is being praised for rethinking conventional solar cells, at a time when costs and performance need to be more closely aligned. While the technological details are complex, the aggressive wish list at Silevo is easy enough to understand and accept—implement low-cost operations to produce a unique technology in order to advance a PV market into a self-sustaining future.One of the Silevo cost-preserving feats is its design of cells that make use of copper rather than silver, as silver pastes have been reported to be the second-highest-priced material in a module after silicon itself.Silevo is taking an aggressive growth path in bringing its technology forward, with plans to maintain its research facility in Fremont and to build a manufacturing plant in Hangzhou, China.Silevo recently closed $33 million in financing from investors, and the money is being used to build the facility in China, as well as to drive further research at its California site.Silevo says it is currently producing modules in pilot production, manufacturing Triex cells that demonstrate between 20% and 21% conversion efficiency on full-size substrates. Customer qualification samples have begun shipping. In the first half of 2012, high-volume commercial production will begin.Silevo’s announcement is conveniently timed, since, in just days, the Solar Power International 2011 is to open its doors, from October 17 through October 20, in Dallas. That event is where professionals get to network and, as the event site suggests, to generate “powerful new ideas” and business for the solar industry. (PhysOrg.com) — Silevo, the Fremont, California, photovoltaic solar module manufacturers, yesterday stepped forward to talk all about their technology for the first time and to say that it offers the best performance-to-cost ratio for solar modules in the industry, thanks to their groundbreaking new design. More information: http://silevosolar.com/ , press release Explore further LG Electronics to Invest in Solar Cell Production Line © 2011 PhysOrg.com Citation: Silevo solar cell makers reveal product with best-ever claims (2011, October 13) retrieved 18 August 2019 from https://phys.org/news/2011-10-silevo-solar-cell-makers-reveal.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
Citation: Lab study indicates feldspar dominates ice nucleation in clouds with mix of water and ice (2013, June 13) retrieved 18 August 2019 from https://phys.org/news/2013-06-lab-feldspar-dominates-ice-nucleation.html Explore further Feldspars are a group of minerals that are believed to make up as much as 60 percent of the Earth’s crust. The name comes from the German words “field” and Spath (rocks that don’t have any ore in them.) Prior research has shown that they make up on average just 3 percent of the dust found in clouds, which has led scientists to conclude that they play a minor role in ice formation. In this new effort, the researchers found just the opposite to be true.The amount of ice that forms in clouds is important because it determines how large clouds grow, how long they last and their radiative properties. Because they make up so much of the mass of dust (about two thirds) in clouds, scientists have believed that clay minerals were responsible for most ice nucleation—where water adheres to dust particles kicking off the formation of ice crystals. Now it appears that feldspars play an inordinately important role.To find out what really goes on inside of clouds, the researchers used special cooling chambers in their lab along with various mixtures of dust created to simulate that found in the natural atmosphere. Water vapor in the chamber formed droplets on slides allowing the researchers to study the ice crystals that grew on the minerals that were in them. By watching the process as it happened, the researchers were able to see that most ice nucleation occurred on feldspars rather than clay mineral material.The findings by the team suggest that human activities may be having a larger impact on cloud formation and their properties than has been previously thought—the amount of feldspars in the atmosphere has been rising consistently over the past several decades due to landscape changes in arid areas. Prior research has shown that dust that winds up in clouds comes predominately from arid regions such as the Sahara desert. An increase in feldspars in the atmosphere, the researchers conclude, may be having a still unknown impact on global climate. (Phys.org) —A team of researchers at Britain’s Institute for Climate and Atmospheric Science, University of Leeds, with assistance from Australian Matthew Woodhouse of Commonwealth Scientific and Industrial Research Organization has found that feldspar minerals play a far larger role in ice formation in clouds than has been realized. In their paper published in the journal Nature, the team describes their lab studies that revealed the important nature of feldspar in ice nucleation in clouds. Cloud in Nepali sky. Credit: Wikipedia More information: The importance of feldspar for ice nucleation by mineral dust in mixed-phase clouds, Nature (2013) doi:10.1038/nature12278AbstractThe amount of ice present in mixed-phase clouds, which contain both supercooled liquid water droplets and ice particles, affects cloud extent, lifetime, particle size and radiative properties1, 2. The freezing of cloud droplets can be catalysed by the presence of aerosol particles known as ice nuclei2. One of the most important ice nuclei is thought to be mineral dust aerosol from arid regions2, 3. It is generally assumed that clay minerals, which contribute approximately two-thirds of the dust mass, dominate ice nucleation by mineral dust, and many experimental studies have therefore focused on these materials1, 2, 4, 5, 6. Here we use an established droplet-freezing technique4, 7 to show that feldspar minerals dominate ice nucleation by mineral dusts under mixed-phase cloud conditions, despite feldspar being a minor component of dust emitted from arid regions. We also find that clay minerals are relatively unimportant ice nuclei. Our results from a global aerosol model study suggest that feldspar ice nuclei are globally distributed and that feldspar particles may account for a large proportion of the ice nuclei in Earth’s atmosphere that contribute to freezing at temperatures below about −15 °C. Dust dries clouds by gobbling up water vapor: Scientists show how different cloud seeds can influence greenhouse effect © 2013 Phys.org Journal information: Nature This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
Credit: Sinfonia Technology/via TechOn Aside from autonomy, another key distinction is that Sinfonia’s robot can handle the fact that not all solar panels are alike; the robot is designed to tackle panels that tilt in different ways. To clean tilted solar panels on a mounting system, the robot can move on a planes tilted at 5-30°. If there is a gap between panels, the robot can go over a gap of 50cm or less and can deal with a height difference of 30cm or less.The robot is powered by a battery and is capable of wireless data transmission. A tablet can be used to check the robot’s status—to check if, for example, it has enough water or to check the battery charge remaining.Sinfonia Technology, in promoting the benefits of its panel-cleaning robots, also noted cost advantages over using manpower for cleaning panels.Generally, experts say that, for large-scale solar panel installations, attention to keeping the panels clean makes sense. Earlier this year, however, a study out of the Jacobs School of Engineering at University of California San Diego, in quantifying losses of electricity output due to dirty solar panels, found panels that hadn’t been cleaned, or rained on, for 145 days during a summer drought in California lost on average a little less than 0.05 percent of their overall efficiency per day. Cleaning the panels often was not worth the cost, found the study’s engineers. They cautioned, though, that their study focused on smaller systems and that, for very large installations, economies of scale may mean that washing panels was worth it.Sharp, meanwhile, is another Japan-based company showing interest in devising automatic ways to clean solar panels. Last month, IDG News Service reported that Sharp, manufacturers of solar panels and generation systems, placed on show at the Ceatec expo in Tokyo an automatic cleaner to latch on to the top of a bank of solar panels and clean them. According to the report, Sharp is working toward commercializing the cleaner, which will first work on the company’s own panels. © 2013 Phys.org Cleaning solar panels often not worth the cost, engineers find More information: www.sinfo-t.jp/eng/index_a.htmvia TechOn This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. (Phys.org) —At large-scale solar plants, keeping the surfaces of solar panels free from dust, sand and bird droppings is not just a matter of finicky housekeeping. It can be a matter of plant profitability. Dirty panels lower power generation efficiencies. Bird droppings on panels, for example, block the sunlight. A Tokyo-based company has a solution. Sinfonia Technology announced late last month that it has developed a robot with camera and sensors that can move autonomously and clean solar panels at large-scale solar power plants. Sinfonia’s robot has a distinction in being “autonomous” in that, rather than tethered to rails, the robot is able to move from panel to panel, to tackle the panels’ dirt and debris. The robot is equipped with scrub brush, wiper and detergent; and also sprinkles water stored in its tank. The robot can work in the dark; it has LEDs, having wavelengths in the infrared range. Citation: Robot with brush, water, wiper tackles solar panel cleaning (2013, December 2) retrieved 18 August 2019 from https://phys.org/news/2013-12-robot-wiper-tackles-solar-panel.html Explore further
Phys.org: Why is this planet so much hotter than Jupiter?Nielsen: The main reason this planet is so much hotter than Jupiter is that it’s so much younger, so it still has a lot of the heat it got when it first formed. Over hundreds of millions of years, it’ll radiate away that heat and cool down, and come to look more and more like Jupiter. So this planet represents a great opportunity to see what Jupiter probably looked like when our solar system was much younger, before the Earth had even finished forming.Phys.org: What was the role of Gemini Observatory’s Planet Imager in this discovery?Nielsen: Discovering 51 Eri b wouldn’t have been possible without GPI. The Gemini Planet Imager was designed from the start to do exactly what it’s doing now, detecting the faintest planets very close to their parent stars and characterizing their atmospheres. Previous instruments at large telescopes have looked at the star 51 Eri over the past decade, but the planet was invisible to them because it just got lost in the glare of the star. As part of the Gemini Planet Imager Exoplanet Survey (GPIES) we have an incredible opportunity to search for these previously-hidden planets and learn about them, and really place our own solar system into context.Phys.org: Is it actually possible that 51 Eridani b could host alien life?Nielsen: While we don’t have the capabilities to detect life or rule it out, based on what we know now, it’s very unlikely that 51 Eri b hosts life. As a gas giant like our own Jupiter, it has no surface or liquid ocean, both important to development of life on Earth. It might be possible for 51 Eri b to have rocky and icy moons, because all the giant planets in our own solar system have multiple moons, which might provide a location for life to develop. However, such hypothetical moons would be completely invisible to our current technology.There’s speculation that life could arise in the oceans of Jupiter’s moon Europa, beneath the 10 to 30 km icy surface, where the liquid water ocean is heated by tidal forces from Jupiter. Though confirming whether life really does or has lived on Europa will require a future probe that can somehow get beneath that surface of ice. Timescale is an important factor. It took about a billion years after Earth formed before life first appeared, and 51 Eri b orbits a star that only formed 20 million years ago, so if moons do form around 51 Eri b that are a good place for life to arise, it’s probably much too early for life to have appeared.Phys.org: What do we know about this planet’s atmosphere?Nielsen: The atmosphere is pretty interesting, and it’s a good deal cooler than extrasolar planet atmosphere we’ve taken spectra of to date. From the spectrum, we can tell that there’s methane and water in its atmosphere, which looks a lot like the inner parts of Jupiter’s atmosphere. Also like Jupiter, 51 Eri b probably has bands of clouds on its surface giving it a striped appearance. Phys.org: Do you plan further observations of the planet? If so, what kind of observations? What instruments do you plan to use?Nielsen: Right now, our sun is between the Earth and 51 Eri, so it’ll be another one to two months before we can observe this planet again. But once it’s visible again, we have lots of plans for future observations, many with GPI. We want to track the orbit of this planet over time, and see if it’s in a mostly circular orbit like the giant planets of our solar system, or if it’s in a very eccentric orbit like many of the closer-in giant planets astronomers have detected around other stars using the radial velocity technique. GPI also allows us to take spectra at shorter and longer wavelengths than our current data, so we can do a more complete comparison to other planets and theoretical models, and really understand what the atmosphere is made of and the bulk properties of the planet. Explore further © 2015 Phys.org This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Phys.org: The discovery created a lot of buzz in various scientific media. Is it really such an important finding, a milestone in the search for exoplanets?Eric Nielsen: The reason we’re all so excited about this is that 51 Eri b is the first time we’ve discovered an extrasolar planet by direct imaging, where the planet looks so much like a giant planet in our own solar system. Other giant planets we have images of are interesting in their own right, but they look very different from what we’re used to. For example, HR 8799 is a massive star that hosts four giant planets between seven and 10 times the mass of Jupiter, between 15 AU and 68 AU. 2MASS 1207 is a brown dwarf with a four-Jupiter-mass planet at 46 AU.The other planets we’ve imaged around other stars tend to be at larger orbital distances and hotter, simply because those are easier to detect, but GPI’s (Gemini Planet Imager) incredible ability to detect faint companions close to their stars means we’re sensitive for the first time to these closer, cooler planets. We still don’t know how often planets like this form, and finding and studying 51 Eri b is an important clue to uncovering how planets form around other stars, and whether the formation of the giant planets in our own solar system was an unlikely fluke or a common process.Phys.org: Does 51 Eridani b resemble Jupiter?Nielsen: 51 Eri b just looks more like something we’re used to seeing in our own solar system, orbiting a star that’s a little more massive than ours, and only twice the mass of Jupiter and at a separation between the orbits of Saturn and Uranus.In addition, the spectrum of 51 Eri b shows that it has a lot of methane in its atmosphere, which is an important component of the atmosphere of our solar system’s giant planets. The other giant planets we’ve imaged around other stars either have very weak or no signs of methane in their spectra, so seeing something more similar to what we’re used to locally is pretty exciting. 51 Eri b is at intermediate temperature, too, at 800 degrees Fahrenheit, it sounds pretty hot by human standards, and certainly compared to Jupiter at -200 degrees Fahrenheit, but it’s significantly cooler than other extrasolar planets which are closer to 1200 degrees Fahrenheit. An artistic conception of the Jupiter-like exoplanet, 51 Eri b, seen in the near-infrared light that shows the hot layers deep in its atmosphere glowing through clouds. Because of its young age, this young cousin of our own Jupiter is still hot and carries information on the way it was formed 20 million years ago. Credit: Danielle Futselaar & Franck Marchis, SETI Institute. (Phys.org)—The discovery of 51 Eridani b, a Jupiter-like exoplanet, made headlines last week as it is the lowest-mass planet ever directly imaged around another star. Significantly, the planet resembles Jupiter in its infancy and shows the strongest methane signature ever detected on an alien planet. In an interview with Phys.org, astronomer Eric Nielsen of the SETI Institute, a member of the team that found 51 Eridani b, talks about the importance of the discovery and characterizes the newest addition to the list of known exoplanets. Citation: ‘Young Jupiter’ exoplanet discovery: Q&A with astronomer Eric Nielsen (2015, August 17) retrieved 18 August 2019 from https://phys.org/news/2015-08-young-jupiter-exoplanet-discovery-qa.html Methane, water enshroud nearby Jupiter-like exoplanet
Explore further This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. 0.1−300 GeV test statistic map of DA 193, generated for the period MJD 54683−58137. Image scale is 0.05 degree per pixel and the black circle denotes the 95% positional uncertainty derived from the Fermi-LAT data analysis. The radio and optimized γ-ray positions are also shown, as labelled. Image credit: Paliya et al., 2018. Blazars, classified as members of a larger group of active galaxies that host active galactic nuclei (AGN), are the most numerous extragalactic gamma-ray sources. Their characteristic features are relativistic jets pointed almost exactly toward the Earth. In general, blazars are perceived by astronomers as high-energy engines serving as natural laboratories to study particle acceleration, relativistic plasma processes, magnetic field dynamics and black hole physics.Studies show that high-redshift blazars (with redshifts above 2.0) hosting massive black holes and the most powerful relativistic jets are the most luminous ones. Finding and observing new blazars at high redshifts could be crucial for providing insights into many phenomena of the universe, including the evolution and space density of massive black holes.A team of researchers led by Vaidehi S. Paliya of DESY research center in Zeuthen, Germany, investigated one such high-redshift blazar. They used the Large Area Telescope (LAT) on board NASA’s Fermi Gamma-ray Space Telescope and other instruments to characterize physical properties DA 193 – a blazar observed close to the galactic anti-center at a redshift of approximately 2.36. These observations resulted in the detection of significant gamma-ray emission from this object.”In this work, we present the results of our study on another high-redshift blazar DA 193 (also known as 0552+398; z = 2.363, Wills & Wills 1976; McIntosh et al. 1999) which we have found as a new gamma-ray emitting object through our detailed Fermi-LAT analysis,” the researchers wrote in the paper.DA 193 underwent a significant GeV flare in the first week of 2018. According to the study, it was an extremely luminous gamma-ray flare with a luminosity of about 130 quindecillion erg/s. The researchers note that such a GeV flare from a high-redshift blazar is a rare phenomenon. This is due to the fact that these blazars are generally faint in the gamma-ray band.Notably, DA 193 has an extremely hard gamma-ray spectrum. “What makes this event a rare one is the observation of an extremely hard γ-ray spectrum (photon index = 1.7 ± 0.2), which is somewhat unexpected since high-redshift blazars typically exhibit a steep falling spectrum at GeV energies,” the paper reads.Trying to determine what caused such an intense and luminous flare from DA 193, the astronomers suggest that a change in the behavior of the underlying electron population could be responsible for the observed event. The team intends to use LAT for further continuous monitoring of the gamma-ray sky in order to find more powerful blazars showcasing luminous flares like DA 193. Studying such events could lead to a better understanding of radiative processes powering relativistic jets in blazars. Citation: Luminous gamma-ray flare detected from the blazar DA 193 (2019, January 3) retrieved 18 August 2019 from https://phys.org/news/2019-01-luminous-gamma-ray-flare-blazar-da.html Blazar LBQS 1319+0039 detected in hard X-rays © 2019 Science X Network An international group of astronomers has detected an intense and extremely luminous gamma-ray flare from one of high-redshift blazars known as DA 193. The new detection, reported in a paper published December 18 on arXiv.org, is an uncommon finding as such bright flares are rarely observed from high-redshift sources. More information: Vaidehi S. Paliya et al. Detection of a gamma-ray flare from the high-redshift blazar DA 193. arXiv:1812.07350 [astro-ph.HE] arxiv.org/abs/1812.07350
What inspired you to translate Dinkar’s epic Urvashi in English?In 2002, I fell from the stairs and fractured my left leg. I was advised a few months’ rest. This gave me the opportunity to read this book by Dinkar. But when I read it, I was astounded at the store-house of high imagination exhibited in depicting the characters of this epic and the natural beauty. Therefore, I thought that this treasure that was hidden in Hindi language should be brought into the open through an English translation, so that many more readers are able to enjoy it. Urvashi in fact dwells in the highest imagination where beauty, intellect, romance, practicality, nature, blessing and curse of life all coalesce into one. She is: ‘Kindler of love in accomplished sages, Igniter of fires in the blood of Gods, Living charm of Venus, grace of the goddess of fortune, the object of desire of all mankinds, Beloved of the moon, the ultimate offering of flame at the hands of the God of love.’ Also Read – ‘Playing Jojo was emotionally exhausting’How difficult was it to translate the work?It was difficult no doubt because even in Hindi I had to often consult dictionaries. But while translating, I had the feeling that some stream is flowing by itself. I have never revised a single line. Even Dinkar ji has said that new poems would not need patch work of choosing words and doing some type of inlaying. The thoughts must gush out. It can happen only when there is intense concentration of ideas. As far as the language of poems is concerned, the path runs very near to the path in prose. No inlaying and patching. Also Read – Leslie doing new comedy special with NetflixHow much has your work, over a long period of time, helped in shaping your thoughts?Literature has a tremendous effect on the thought process. This is the age of science. But the character of mankind has not changed a lot from the time when men were dwelling in caves. Means have changed. Science and technology can do more destruction if not tempered with literature and arts. Science and technology has brought abundance in means but the pond of the heart is dry. No lotus there. Only anger, hate, poison. When Science and rechnology would pose a threat to devour mankind, literature and arts would come to the rescue. Unfortunately, in the course-curricula, mostly subjects of only commercial values are being taught. The emphasis on teaching those subtle things which are for the heart is missing. Who are the other writers you look up to?The age of poems is getting lost due to various reasons. But what poems can do is difficult to accomplish otherwise. I like Mahadevi Verma, Maithilisharan Gupta, Nepali, Bachchan, Nirala, Jaishankar Prasad, Rabindranath, Subhadra, Makhan Lal Chaturvedi and others.