Tag Archives: #gas

Quasars Rip Across Galaxies Like Tsunamis (Astronomy)

Using the unique capabilities of NASA’s Hubble Space Telescope, a team of astronomers has discovered the most energetic outflows ever witnessed in the universe. They emanate from quasars and tear across interstellar space like tsunamis, wreaking havoc on the galaxies in which the quasars live.

Image Credit: NASA, ESA and J. Olmsted (STScI)

This illustration shows a distant galaxy with an active quasar at its center. A quasar emits exceptionally large amounts of energy generated by a supermassive black hole fueled by infalling matter. Using the unique capabilities of Hubble, astronomers have discovered that blistering radiation pressure from the vicinity of the black hole pushes material away from the galaxy’s center at a fraction of the speed of light. The “quasar winds” are propelling hundreds of solar masses of material each year. This affects the entire galaxy as the material snowplows into surrounding gas and dust.

Provided by NASA

World’s First Gas Sample From Deep Space Confirmed (Astronomy)

The Japan Aerospace Exploration Agency (JAXA) has confirmed that the gas collected from the sample container inside the re-entry capsule of the asteroid explorer, Hayabusa2, is a gas sample originating from asteroid Ryugu.

Figure 1: Sample container structure Credit: JAXA

The result of the mass spectrometry of the collected gas within the sample container performed at the QLF (Quick Look Facility) established at the Woomera Local Headquarters in Australia on December 7, 2020, suggested that the gas differed from the atmospheric composition of the Earth. For additional confirmation, a similar analysis was performed on December 10-11 at the Extraterrestrial Sample Curation Center on the JAXA Sagamihara Campus. This has led to the conclusion that the gas in the sample container is derived from asteroid Ryugu.

The grounds for making this decision are due to the following three points.

i) Gas analysis at the Extraterrestrial Sample Curation Center and at the Woomera Local Headquarters in Australia gave the same result.
ii) The sample container is sealed with an aluminum metal seal and the condition of the container is as designed, such that the inclusion of the Earth’s atmosphere was kept well below the permissible level during the mission. (iii) Since it was confirmed on the Sagamihara campus that gas of the same composition had been generated even after the removal of the container gas in Australia, it is considered that the collected gas must be due to the degassing from the sample.

Figure 2: Equipment for gas analysis brought to the Woomera Local Headquarters in Australia. Credit: JAXA

This is the world’s first sample return of a material in the gas state from deep space.

The initial analysis team will continue with opening the sample container and performing a detailed analysis of the molecular and isotopic composition of the collected gas.

Provided by JAXA

How Giant Planets Turn Gas into Metal? (Planetary Science)

New theoretical insights and space mission data have changed our perception of the solar system’s largest planets. Scientists from the University of Zurich involved in the National Centre of Competence in Research PlanetS have reviewed our current state of knowledge.

Picture of Jupiter taken by NASA spaceships Juno and Cassini. (Image: NASA/JPL-Caltech/SwRI/MSSS/Kevin Gill/Maksim Kakitsev)

Earth is a terrestrial planet. It consists of a mostly solid rocky crust and molten mantle, which flow on a liquid outer metal core. This core, in turn, is centered by a solid inner core of metal. Knowing these things helps us understand our home world. Explaining the existence of mountains, for example, or its magnetic field, would otherwise be difficult.

Gas planets are another story. They mostly consist of light elements and are thus are fundamentally different from that of Earth and co. “Understanding these planets requires knowledge about the behavior of their main constituents – hydrogen and helium – under conditions that do not exist on Earth,” explains Ravit Helled, professor of theoretical astronomy at the University of Zurich. She and her colleagues reviewed recent progress of this knowledge and combined it with new space mission data to paint an updated picture of the giant gas planets of our solar system: Jupiter and Saturn.

Interface between two fields of physics

These planets are anything but new objects of scientific interest. “For decades scientists have tried to estimate Jupiter’s core mass and bulk composition, but there has been little consensus,” Helled points out. One of the main difficulties of learning about these planets is that there are no direct measurements that could reveal information about their interior structure, like for example seismic measurements. Instead, scientists have to rely on indirect measurements like mass, radius and the planet’s gravity field. The latter reveals how mass is distributed within them. “Thanks to the precise measurements of the NASA Juno and Cassini missions, we have a much better idea about the gravity fields of Jupiter and Saturn,” says Helled.

Meanwhile, back on Earth, scientists also progressed in an entirely different area: experimental techniques using diamond anvil cells. With these devices, material – for example hydrogen – can be compressed to extreme pressures (equivalent up to several hundred million atmospheres). Such experiments as well as accurate computer simulations revealed how under these conditions – that can also be found in the interior of giant planets – hydrogen behaves like a fluid metal.

Together with the detailed recent gravity field measurements, these findings reveal that the interior of giant gas planets is more complex than previously thought. Instead of layered structures with distinct cores, they appear to have interiors that are better described by composition gradients with dilute cores that Helled calls “fuzzy”. “This gives us a new view of these giant gas planets,” she says, “and will help characterize giant gas planets around other stars.”

A better understanding of our own history

This new view not only leads to a better understanding of the structure and formation processes of the giant gas planets themselves. Because of their critical role in planetary systems, it also helps the scientists to understand the evolution of the entire solar system. With their enormous mass and strong gravity, they had a profound influence on trajectories of small objects, like asteroids, in the young solar system. Thus, they controlled what impacted on the inner planets, including Earth. These findings are an important reminder of how the study of seemingly unrelated fields can have a direct influence on our understanding of our place in the world.

References: Helled, R., Mazzola, G. & Redmer, R. Understanding dense hydrogen at planetary conditions. Nat Rev Phys 2, 562–574 (2020). https://doi.org/10.1038/s42254-020-0223-3 link: https://www.nature.com/articles/s42254-020-0223-3

Provided by University of Zurich

Astronomers Revealed Most Detailed Image Yet Of Famous Stellar Nursery (Astronomy)

Astronomers using the international Gemini Observatory, a Program of NSF’s NOIRLab, have captured the western wall of the Carina Nebula in unprecedented detail in a compelling image released today. The image reveals a number of unusual structures in the nebula. The exquisite detail revealed in the image is in part due to a technology known as adaptive optics, which resulted in a ten-fold improvement in the sharpness of the research team’s observations.

A 50-trillion-km (33-trillion-mile, or 5 light-year) long section of the western wall in the Carina Nebula, as observed with adaptive optics on the Gemini South telescope. This mountainous section of the nebula reveals a number of unusual structures including a long series of parallel ridges that could be produced by a magnetic field, a remarkable almost perfectly smooth wave, and fragments that appear to be in the process of being sheared off the cloud by a strong wind. There is also evidence for a jet of material ejected from a newly-formed star. The exquisite detail seen in the image is in part due to a technology known as adaptive optics, which resulted in a ten-fold improvement in the resolution of the research team’s observations. ©International Gemini Observatory/NOIRLab/NSF/AURA Acknowledgment: PI: Patrick Hartigan (Rice University) Image processing: Patrick Hartigan (Rice University), Travis Rector (University of Alaska Anchorage), Mahdi Zamani & Davide de Martin

There is no better location to investigate the birth of stars than nebulae — regions of gas and dust where stars coalesce, heat up and start to glow. The brilliant Carina Nebula, located in the southern hemisphere sky, is 500 times larger in actual area than the better-known Orion Nebula, making it an ideal candidate for investigating star formation.

The team used adaptive optics on the 8.1-meter Gemini South telescope in Chile to significantly improve upon previous observations of the Carina Nebula’s western wall, the well-defined edge of the nebula. Adaptive optics compensates for the effects of turbulence in the Earth’s atmosphere to produce pin-sharp images, comparable to those from a space telescope. Indeed, this image is reminiscent of the famous Hubble Pillars of Creation in the Eagle Nebula.

Star-forming regions are shrouded in dust but it is possible to see through the shroud of dust by observing in infrared light. The team, led by Patrick Hartigan of Rice University, utilized the Gemini South Adaptive Optics Imager (GSAOI), a near-infrared adaptive optics camera, to peer through the outer layers of dust to reveal a huge wall of dust and gas glowing with the intense ultraviolet light from nearby massive young stars. This region is a great example of such a wall and this image provides a very clear view of a star-forming region in the near-infrared [1].

This exterior shot of Gemini South shows the result of the Gemini Multi-conjugate adaptive optics System (GeMS) with the Gemini South Adaptive Optics Imager (GSAOI) propagating a laser guide star toward the zenith. Gemini South acquired the 50-watt sodium Guide Star Laser System back in March 2010. It moved into regular operations soon thereafter. The GeMS/GSAOI system is a revolutionary approach to adaptive optics in astronomy. The technique samples the turbulence structure in the atmosphere at several levels and then uses a technique similar to medical tomography to reconstruct a 3D snapshot of how the atmosphere is distorting starlight. This is then used to shape a series of deformable mirrors to cancel out this distortion. All of this happens about 1,000 times a second. In the sky, to the upper left of the dome, floating like detached fragments of the Milky Way, lie the Large and Small Magellanic Clouds. These nebulous wonders are actually irregular dwarf galaxy companions to the Milky Way some 200,000 light years distant. Gemini dedicates this image to the memory of Vincent Fesquet, who worked tirelessly to make the Gemini South laser guide star system work efficiently and reliably. Credit: International Gemini Observatory/AURA/M. Paredes

With a resolution ten times higher than it would be without adaptive optics from the ground [2], the image reveals a wealth of detail never observed before. This mountainous section of the nebula reveals a number of unusual structures. There is a long series of parallel ridges that could be produced by a magnetic field, a remarkable almost perfectly smooth wave, and fragments that appear to be in the process of being sheared off the cloud by a strong wind. There is also evidence for a jet of material ejected from a newly-formed star.

The image provides the sharpest view to date of how massive young stars affect their surroundings and influence how star and planet formation proceeds. “It is possible that the Sun formed in such an environment,” said Hartigan. “If so, radiation and winds from any nearby massive stars would have affected the masses and atmospheres of the Solar System’s outer planets.” Astronomers are just beginning to model how such stars affect the evolution of planetary systems.

This spectacular image is a wonderful demonstration of the effectiveness of adaptive optics. It is also the first time that this region has been observed using this technique, so every new detail is a fascinating first glimpse for astronomers and the general public alike, and gives a taste of what could be possible with the upcoming James Webb Space Telescope.

References: Patrick Hartigan, Turlough Downes, and Andrea Isella, “A JWST Preview: Adaptive-optics Images of H2, Br-γ, and K-continuum in Carina’s Western Wall”, The Astrophysical Journal Letters, Volume 902, Number 1, 2020 link: https://iopscience.iop.org/article/10.3847/2041-8213/abac08 doi: http://dx.doi.org/10.3847/2041-8213/abac08

Provided by ASSOCIATION OF UNIVERSITIES FOR RESEARCH IN ASTRONOMY (AURA)

ESO Telescope Spots Galaxies Trapped In The Web Of A Supermassive Black Hole (Astronomy)

With the help of ESO’s Very Large Telescope (VLT), astronomers have found six galaxies lying around a supermassive black hole when the Universe was less than a billion years old. This is the first time such a close grouping has been seen so soon after the Big Bang and the finding helps us better understand how supermassive black holes, one of which exists at the centre of our Milky Way, formed and grew to their enormous sizes so quickly. It supports the theory that black holes can grow rapidly within large, web-like structures which contain plenty of gas to fuel them.

With the help of ESO’s Very Large Telescope (VLT), astronomers have found six galaxies lying around a supermassive black hole, the first time such a close grouping has been seen within the first billion years of the Universe. This artist’s impression shows the central black hole and the galaxies trapped in its gas web. The black hole, which together with the disc around it is known as quasar SDSS J103027.09+052455.0, shines brightly as it engulfs matter around it.
CREDIT: ESO/L. Calçada

“This research was mainly driven by the desire to understand some of the most challenging astronomical objects — supermassive black holes in the early Universe. These are extreme systems and to date we have had no good explanation for their existence,” said Marco Mignoli, an astronomer at the National Institute for Astrophysics (INAF) in Bologna, Italy, and lead author of the new research published today in Astronomy & Astrophysics.

The new observations with ESO’s VLT (https://www.eso.org/public/teles-instr/paranal-observatory/vlt/) revealed several galaxies surrounding a supermassive black hole, all lying in a cosmic “spider’s web” of gas extending to over 300 times the size of the Milky Way. “The cosmic web filaments are like spider’s web threads,” explains Mignoli. “The galaxies stand and grow where the filaments cross, and streams of gas — available to fuel both the galaxies and the central supermassive black hole — can flow along the filaments.”

The light from this large web-like structure, with its black hole of one billion solar masses, has travelled to us from a time when the Universe was only 0.9 billion years old. “Our work has placed an important piece in the largely incomplete puzzle that is the formation and growth of such extreme, yet relatively abundant, objects so quickly after the Big Bang,” says co-author Roberto Gilli, also an astronomer at INAF in Bologna, referring to supermassive black holes.

The very first black holes, thought to have formed from the collapse of the first stars, must have grown very fast to reach masses of a billion suns within the first 0.9 billion years of the Universe’s life. But astronomers have struggled to explain how sufficiently large amounts of “black hole fuel” could have been available to enable these objects to grow to such enormous sizes in such a short time. The new-found structure offers a likely explanation: the “spider’s web” and the galaxies within it contain enough gas to provide the fuel that the central black hole needs to quickly become a supermassive giant.

But how did such large web-like structures form in the first place? Astronomers think giant halos of mysterious dark matter are key. These large regions of invisible matter are thought to attract huge amounts of gas in the early Universe; together, the gas and the invisible dark matter form the web-like structures where galaxies and black holes can evolve.

“Our finding lends support to the idea that the most distant and massive black holes form and grow within massive dark matter halos in large-scale structures, and that the absence of earlier detections of such structures was likely due to observational limitations,” says Colin Norman of Johns Hopkins University in Baltimore, US, also a co-author on the study.

The galaxies now detected are some of the faintest that current telescopes can observe. This discovery required observations over several hours using the largest optical telescopes available, including ESO’s VLT. Using the MUSE (https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/muse/) and FORS2 (https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/fors/) instruments on the VLT at ESO’s Paranal Observatory in the Chilean Atacama Desert, the team confirmed the link between four of the six galaxies and the black hole. “We believe we have just seen the tip of the iceberg, and that the few galaxies discovered so far around this supermassive black hole are only the brightest ones,” said co-author Barbara Balmaverde, an astronomer at INAF in Torino, Italy.

These results contribute to our understanding of how supermassive black holes and large cosmic structures formed and evolved. ESO’s Extremely Large Telescope, currently under construction in Chile, will be able to build on this research by observing many more fainter galaxies around massive black holes in the early Universe using its powerful instruments.

References: Marco Mignoli, Roberto Gilli, Roberto Decarli et al., ‘Web of the giant: Spectroscopic confirmation of a large-scale structure around the z=6.31 quasar SDSS J1030+0524″, Astronomy & Astrophysics manuscript no. 39045, ESO 2020, pp.1-8 doi: https://doi.org/10.1051/0004-6361/202039045

Provided by ESO

Holding Your Farts Has Some Unexpected Consequences (Biology)

Everybody’s been there at some point. You’re in a situation when propriety is paramount — a job interview, a fancy dinner, in the middle of reading your wedding vows — when you start to feel a bit of pressure in your lower intestine. It’s building … and building … and it’s gradually becoming an emergency situation. But you gather all of your fortitude and hold it in until, finally, mercifully, the pressure subsides. But did you ever wonder where that gas went?

Here’s what happens when you hold in a fart — and why you shouldn’t do it too much.

Let’s get something clear. We’re not going to go on record as saying that you should let ‘er rip every time you feel the need. But the gas that comprises your farts is as subject to the same laws of thermodynamics as anything else — like all matter and energy, it can’t be created or destroyed. It’s got to go somewhere.

Hold it in too long, and you could end up with some uncomfortable abdominal distension, which might contribute to a painful condition known as diverticulitis. The condition occurs when small bubbles or pouches form along the intestinal wall and become inflamed. It’s certainly not something you want to experience firsthand. However, the true causes of diverticulitis are hazy, so take that with a grain of salt. But besides that gas (possibly) secreting itself away in intestinal pockets, it also can be reabsorbed into your bloodstream, where it remains until its next chance to break free.

As for what’s next, well, you’re probably not going to like it. It has to do with methane. Despite the bad rap that methane gets for its role in our plumbing, it’s actually not the most prominent gas your personal exhaust vent lets loose. In fact, many people don’t produce methane at all. But among the 30 to 60 percent of people that do, it provides a powerful tool for tracking the path of errant farts. Since methane production is more of a side effect of digestion than anything else, it can really only come from one place in the body. And as it turns out, if you produce methane and you hold in your farts, you’ll just end up breathing it out your mouth and nose instead. That’s right — slam the door in a fart’s face, and it just takes the elevator up.

We’ll be honest: That’s probably more than we needed to know. But finding out that methane isn’t the source of fart smells has got us questioning everything else we assumed about the back-door symphony. Instead, it’s sulfur-containing gases like hydrogen sulfide that shoulder the blame for the smelliest poots. Your microbiome is largely responsible for the content of your farts, as it turns out, but their quantity is determined largely by your diet.

In one study, researchers found that both men and women produced a median of about 700 milliliters (about 3 cups) of gas per day. On the lower end of the scale were 476-milliliter farters (roughly 2 cups), while overachievers produced nearly 1500 milliliters of gas (6 cups) every day. When people went on a high-fiber diet, these numbers changed in some interesting ways. They would fart less, as a matter of fact, but produce more gas per fart, leaving the daily levels roughly the same.

At the end of the day, it might not be appropriate for polite company, but it’s probably better to give yourself some relief than walk around with extra baggage. Just do us all a favor and find a secluded place first.

Physicists Proposed Quantum Thermometer To Measure The Coldest Temperatures In The Universe (Quantum)

Physicists from Trinity College Dublin have proposed a thermometer based on quantum entanglement that can accurately measure temperatures a billion times colder than those in outer space. These ultra-cold temperatures arise in clouds of atoms, known as Fermi gasses, which are created by scientists to study how matter behaves in extreme quantum states.

Fig. Schematic depiction of the system. (a) A cold Fermi gas
(blue) is perturbed by a localised impurity (grey) with two internal
states that undergo pure dephasing. (b) Scattering from the impurity disturbs the atoms initial equilibrium distribution, f(E). Pauli
blocking restricts the resulting particle-hole excitations to a region near the Fermi surface. (c) The creation of holes eventually allows further scattering to generate excitations deep within the Fermi sea.

But, what exactly is a Fermi gas? According to Professor Goold, head of Trinity’s QuSys group: All particles in the universe, including atoms, come in one of two types called ‘bosons’ and ‘fermions.'” A Fermi gas comprises fermions, named after the physicist Enrico Fermi. At very low temperatures, bosons and fermions behave completely differently. While bosons like to clump together, fermions do the opposite. They are the ultimate social distancers! This property actually makes their temperature tricky to measure.

According to Dr. Mark Mitchison: The temperature of an ultra-cold gas is inferred from its density: at lower temperatures the atoms do not have enough energy to spread far apart, making the gas denser. But fermions always keep far apart, even at ultra-low temperatures, so at some point the density of a Fermi gas tells them nothing about temperature. Instead, they proposed using a different kind of atom as a probe. Let’s say that we have an ultra-cold gas made of lithium atoms. We now take a different atom, say potassium, and dunk it into the gas. Collisions with the surrounding atoms change the state of our potassium probe and this allows us to infer temperature. Technically speaking, their proposal involves creating a quantum superposition: a weird state where the probe atom simultaneously does and doesn’t interact with the gas. They showed that this superposition changes over time in a way that is very sensitive to temperature.

They demonstrated that the temperature of a noninteracting Fermi gas can be accurately inferred from the nonequilibrium dynamics of impurities immersed within it, using an interferometric protocol and established experimental methods. Adopting tools from the theory of quantum parameter estimation, they showed that their proposed scheme achieves optimal precision in the relevant temperature regime for degenerate Fermi gases in current experiments.

They also discovered an intriguing trade-off between measurement time and thermometric precision that is controlled by the impurity-gas coupling, with weak coupling leading to the greatest sensitivities. This is explained as a consequence of the slow decoherence associated with the onset of the Anderson orthogonality catastrophe, which dominates the gas dynamics following its local interaction with the immersed impurity.


References: Mark T. Mitchison et al. In Situ Thermometry of a Cold Fermi Gas via Dephasing Impurities, Physical Review Letters (2020). DOI: 10.1103/PhysRevLett.125.080402 link: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.080402

Chemist Fritz Haber Was Both A Hero And A Villian (Chemistry)

As a patriotic German and an ambitious chemist, the young Fritz Haber was eager to make his country a better place.

The turn of the 20th century saw growing populations and farmland that couldn’t sustain the crops required to feed them. The soil needed nitrogen, and the only ways to get it were costly and inefficient. With engineer Carl Bosch, Haber discovered a way to capture nitrogen and hydrogen from the air and turn it into ammonia, which could then be used for mass quantities of nitrogen-rich fertilizer. This invention, known as the Haber-Bosch process, saved millions from starving and won both men a Nobel Prize decades later. But before receiving that accolade, Haber joined the German war effort and began using his process to create lethal chlorine gas for use at the front lines of battle. Over the course of the war, this and other poison gases that Haber created brought millions of soldiers to gruesome ends. It also eventually led to the creation of Zyklon B, the compound used in Nazi concentration camps to murder prisoners in gas chambers. It’s not clear whether Fritz Haber saved more lives than he ended, but as his godson, historian Fritz Stern once wrote, “He left a rich legacy — the darker sides of which our darker age can better ponder.” To know more please watch the video given below:

VLT Obtained Incredibly Beautiful Image of Planetary Nebula: NGC 2899 (Astronomy)

Astronomers using the FORS (FOcal Reducer and low dispersion Spectrograph) instrument on ESO’s Very Large Telescope (VLT) have obtained a stunning image of the planetary nebula NGC 2899. This object has never before been imaged in such striking detail, with even the faint outer edges of NGC 2899 glowing over the background stars.

Fig: This highly detailed image of the planetary nebula NGC 2899 was captured using the FORS instrument on ESO’s Very Large Telescope. Image credit: ESO.

Unlike what their common name suggests, planetary nebulae have nothing to do with planets.

The first astronomers to observe these objects merely described them as planet-like in appearance.

They are instead formed when ancient stars with up to 6 times the mass of our Sun reach the end of their lives, collapse, and blow off expanding shells of gas, rich in heavy elements.

Intense ultraviolet radiation energizes and lights up these moving shells, causing them to shine brightly for thousands of years until they ultimately disperse slowly through space, making planetary nebulae relatively short-lived phenomena on astronomical timescales.

NGC 2899 is located between 3,000 and 6,500 light-years away in the southern constellation of Vela.

Also known as Gum 27, ESO 166-13, Hen 2-30 and PN G277.1-03.8, the nebula was discovered by the English astronomer John Herschel on February 27, 1835.

NGC 2899’s vast swathes of gas extend up to a maximum of two light-years from its center, glowing brightly in front of the stars of the Milky Way as the gas reaches temperatures upwards of 10,000 degrees Celsius.

The high temperatures are due to the large amount of radiation from the nebula’s parent star, which causes the hydrogen gas in the nebula to glow in a reddish halo around the oxygen gas, in blue.

NGC 2899 has two central stars, which are believed to give it its nearly symmetric appearance.

After one star reached the end of its life and cast off its outer layers, the other star now interferes with the flow of gas, forming the two-lobed shape seen here.

Only about 10-20% of planetary nebulae display this type of bipolar shape.

The team of ESO astronomers were able to capture this highly detailed image of NGC 2899 using the FORS instrument installed on UT1 (Antu), one of the four 8.2-m telescopes that make up VLT.

This high-resolution instrument was one of the first to be installed on VLT and is behind numerous beautiful images and discoveries from ESO.

References: (1) https://www.eso.org/sci/facilities/paranal/instruments/fors.html (2) https://www.eso.org/public/teles-instr/paranal-observatory/vlt/ (3) https://link.springer.com/book/10.1007/978-94-009-7233-9 (4) http://simbad.u-strasbg.fr/simbad/sim-id?Ident=NGC+2899 (5) https://www.webcitation.org/6Zq2sX0lX (6) https://www.webcitation.org/6Zq75bGhG (7) http://cseligman.com/text/atlas/ngc28a.htm#2899