Evidence of Alien Planets? No, It's Just Gas

The Fomalhaut system contains a cleared ring (shining brightly in this image) in the dust around the star. 

Scientists suspect that this gap was cleared by a pair of terrestrial planets, but new research reveals that the presence of gas could also create such a breach.

CREDIT: NASA, ESA, and P. Kalas (University of California, Berkeley)

Ring-shaped gaps in the gas around a newborn star system can trick astronomers into thinking that baby planets are forming there when they actually aren't, scientists say.

New simulations show that a sufficient concentration of gas in the disk around a young star could cause the dust to clump together to form rings, creating paths that resemble those cleared by newly formed exoplanets.

Gravity binds dust and rock together. The small clumps collect more material as they travel, eventually clearing out rings in their systems that scientists say could host alien planets.

Wladimir Lyra

These systems make good targets in the ongoing search for new worlds. But imaging such planets is a challenge because the light reflecting from them can be as much as a billion times dimmer than the light from their parent star.

"Directly imaged planets are among the hardest to find," said Wladimir Lyra, of NASA's Jet Propulsion Laboratory. "One solution is that they may simply not be there."

Planting false evidence
Spinning disks of dust and gas give rise to newborn stars. After the stars are formed, the remaining materialcan continue to collapse to create new solar systems.

"Disks start as a mixture of usually 100 times more gas than dust," Lyra told reporters. "When the star is formed, its light will slowly evaporate the gas, taking around 10 million years to dissipate it completely."

Marc Kuchner

Lyra and colleague Marc Kuchner of NASA's Goddard Space Flight Center studied how the gas and dust within these disks might interact by creating two- and three-dimensional models of such systems.

"The dust heats the gas by the photoelectric effect — an effect explained by Albert Einstein back in 1905 in a landmark paper that eventually led to the development of quantum mechanics," Lyra said.

Studies Link the Rise Of Significant Earthquakes to Oil and Gas extraction

Two new papers tie a recent increase in significant earthquakes to re-injection of wastewater fluids from unconventional oil and gas drilling.

The first study notes “significant earthquakes are increasingly occurring within the United States midcontinent.” In the specific case of Oklahoma, a Magnitude “5.7 earthquake and a prolific sequence of related events … were likely triggered by fluid injection.”

The second study, of the Raton Basin of Southern Colorado/Northern New Mexico by a U.S. Geological Survey (USGS) team, concludes;

”the majority, if not all of the earthquakes since August 2001 have been triggered by the deep injection of wastewater related to the production of natural gas from the coal-bed methane field here.”

Both studies are being presented at the annual meeting of the American Geophysical Union this week.

These studies, together with other recent findings, make a strong case that we need national regulations on wastewater injection to prevent induced earthquakes.

Background
As hydraulic fracturing has exploded onto the scene, it has increasingly been connected to earthquakes. Some quakes may be caused by the original fracking — that is, by injecting a fluid mixture into the earth to release natural gas (or oil).

More appear to be caused by reinjecting the resulting brine deep underground.

In August 2011, a USGS report examined a cluster of earthquakes in Oklahoma and reported:

Our analysis showed that shortly after hydraulic fracturing began small earthquakes started occurring, and more than 50 were identified, of which 43 were large enough to be located. Most of these earthquakes occurred within a 24 hour period after hydraulic fracturing operations had ceased.

In November 2011, a British shale gas developer found it was “highly probable” its fracturing operations caused minor quakes.

In March 2012, Ohio oil and gas regulators said “A dozen earthquakes in northeastern Ohio were almost certainly induced by injection of gas-drilling wastewater into the earth.”

In April, the USGS delivered a paper at the annual meeting of the Seismological Society of America that noted “a remarkable increase in the rate of [magnitude 3.0] and greater earthquakes is currently in progress” in the U.S. midcontinent.

The USGS scientists pointed out that ”a naturally-occurring rate change of this magnitude is unprecedented outside of volcanic settings or in the absence of a main shock, of which there were neither in this region.”

They concluded:

While the seismicity rate changes described here are almost certainly manmade , it remains to be determined how they are related to either changes in extraction methodologies or the rate of oil and gas production.

Tissint meteorite fragment may contain Martian gas.

A fragment of the Tissint meteorite. Regions of black glass are thought to contain gas, rock and traces of Martian soil. 

Photograph: Natural History Museum, London

A lump of space rock that shattered the predawn calm of the Moroccan desert with a fireball and double sonic boom last year was knocked off Mars in a cosmic collision roughly 700,000 years ago.

The date of the Martian impact means the rock was flung into space and began its journey to Earth when the shared ancestor of modern humans and Neanderthals was still alive and well in Africa.

Scientists dated the collision through a fresh analysis of the remains of the meteorite, based on the exposure of its elements to intense cosmic rays during its journey through space.

The Tissint meteorite, as it is known, is particularly valuable because it was recovered before it had suffered any weathering on Earth.

Witnesses said it split in two as it fell to Earth and landed in the desert near Tata, south-east Morocco, at 2am local time on 18 July last year.

Pieces weighing between 100g and 2kg have been recovered, along with thousands of smaller fragments. The intact meteorite is estimated to have weighed 17kg.

Researchers at the Hassan II University of Casablanca found regions of black glass inside the meteorite that are thought to contain gas, rock and traces of Martian soil.

Hasnaa Chennaoui Aoudjehane

"What is really exciting in this meteorite is that it has this black glass trapped inside," said Hasnaa Chennaoui Aoudjehane, who worked on the specimen.

Further analysis of the glass and the gas locked up in its tiny bubbles may help scientists reconstruct the conditions on Mars when the rock was blasted into space.

"Those bubbles are interesting because they trapped Martian conditions at the moment the meteorite formed, and it hasn't had any exchange with other materials," Chennaoui Aoudjehane said.

The research appears in the latest issue of Science.

Chemist finds new material (ZIF-8): Remove radioactive gas from spent nuclear fuel

Sandia chemist Tina Nenoff heads a team of researchers focused on removal of radioactive iodine from spent nuclear fuel.

They identified a metal-organic framework that captures and holds the volatile gas, a discovery that could be used for nuclear fuel reprocessing and other applications. (Photo by Randy Montoya)

The Sandia researchers have used metal-organic frameworks (MOFs) to capture and remove volatile radioactive gas from spent nuclear fuel.

“This is one of the first attempts to use a MOF for iodine capture,” said chemist Tina Nenoff of Sandia’s Surface and Interface Sciences Department.

The discovery could be applied to nuclear fuel reprocessing or to clean up nuclear reactor accidents.

A characteristic of nuclear energy is that used fuel can be reprocessed to recover fissile materials and provide fresh fuel for nuclear power plants. Countries such as France, Russia and India are reprocessing spent fuel.

The process also reduces the volume of high-level wastes, a key concern of the Sandia researchers. “The goal is to find a methodology for highly selective separations that result in less waste being interred,” Nenoff said.

Part of the challenge of reprocessing is to separate and isolate radioactive components that can’t be burned as fuel. The Sandia team focused on removing iodine, whose isotopes have a half-life of 16 million years, from spent fuel.

They studied known materials, including silver-loaded zeolite, a crystalline, porous mineral with regular pore openings, high surface area and high mechanical, thermal and chemical stability.

Various zeolite frameworks can trap and remove iodine from a stream of spent nuclear fuel, but need added silver to work well.

“Silver attracts iodine to form silver iodide,” Nenoff said. “The zeolite holds the silver in its pores and then reacts with iodine to trap silver iodide.”

But silver is expensive and poses environmental problems, so the team set out to engineer materials without silver that would work like zeolites but have higher capacity for the gas molecules.

They explored why and how zeolite absorbs iodine, and used the critical components discovered to find the best MOF, named ZIF-8.

Satellite observes spatiotemporal variations in mid-upper tropospheric methane over China

To understand the profile of methane in China and provide data for validation of satellite products, Fourier Transform Infrared Spectroscopy (FTIR) measurements were made at a ground-based hyperspectral remote sensing laboratory at the National Satellite Meteorological Center.

Atmospheric methane (CH4), one of the main greenhouse gases, has increased dramatically worldwide since the pre-industrial era. However, much work is needed to build on intermittent and scattered observations since the 1960s and systematic study since the 1980s.

Since 1983, the World Meteorological Organization (WMO) has coordinated global in-situ measurement of methane. Quantification of methane emissions still has large uncertainties, mainly because of undersampling over most regions of the globe by surface observation networks.

In particular, spatiotemporal variations of mid-upper tropospheric methane in China are not well understood, because of limited in-situ measurements.

Dr. ZHANG Xingying and his group at the National Satellite Meteorological Center of the China Meteorological Administration tackled this problem using satellite observations.

Using Atmospheric Infrared Sounder (AIRS) methane data from 2003 to 2008, they revealed spatiotemporal variations of mid-upper tropospheric methane in China.

Their study shows that in the mid troposphere, a center of low CH4 concentration is located over western China, attributable to minimal industrial and agricultural activity. The lowest CH4 mixing ratio in the upper troposphere is over southern China, related to atmospheric transport from the ocean.

A seasonal cycle of methane has been discovered. One peak in summer and the other in winter over eastern, northeastern and northwestern China. Only one peak (in summer) occurs over southern and western China.

Before 2007, CH4 mixing ratio was nearly stable. The average mixing ratio during the last 6 years over major northern hemispheric countries is similar.

However, there has been a significant increase in tropospheric CH4 concentrations after 2007 in most northern hemispheric areas, with slightly larger increases over China.

Dr. ZHANG Xingying has stated that the trend of CH4 based on satellite observation is still somewhat uncertain, because of the short, 6-year dataset. More satellite data of higher quality are needed for further trend analysis.

To understand the profile of methane in China and provide data for validation of satellite products, Fourier Transform Infrared Spectroscopy (FTIR) measurements were made at a ground-based hyperspectral remote sensing laboratory at the National Satellite Meteorological Center.

A Bruker FTIR instrument (IFS 120 M, made in Ettlingen, Germany) with 0.008 cm-1 spectral resolution, was used for observations. Several years of data have been collected.

Implementation and promotion of this work will publicize methane spatiotemporal variations and their potential sources. In so doing, informed efforts may be mounted to reduce methane emission and resulting global climate change.

The National Satellite Meteorological Center manages satellite climate products in China. Two payloads for greenhouse gas monitoring are in development for the next satellite. One of the payloads is similar to AIRS for mid-upper tropospheric greenhouse gases.

The other is for low tropospheric greenhouse gases, and uses a near-infrared (NIR) spectrometer. Meanwhile, more in-situ measurements have been carried out in China for more detailed investigation of greenhouse gases.

Dr. XIONG Xiaozhen, an expert from NOAA, is in charge of AIRS methane product retrieval. He believes that this study is the first to use satellite data for analyzing mid-upper tropospheric methane over China, and represents important step in the study of climate change.

ESA ESO VLT: Gaseous ring around young star V1052 Centaurus

Artist's conception image of a young star surrounded by a disk (made up of rings) (Credits: NASA/JPL-Caltech)

Astronomers have detected a mysterious ring of carbon monoxide gas around the young star V1052 Cen, which is about 700 light years away in the southern constellation Centaurus.

The ring is part of the star’s planet-forming disk, and it’s as far from V1052 Cen as Earth is from the sun. Discovered with the European Southern Observatory's Very Large Telescope, its edges are uniquely crisp.

Carbon monoxide is often detected near young stars, but the gas is usually spread through the planet-forming disk. What’s different about this ring is that it is shaped more like a rope than a dinner plate, said Charles Cowley, professor emeritus in the University of Michigan who led the international research effort.

“It’s exciting because this is the most constrained ring we've ever seen, and it requires an explanation,” Cowley said. “At present time, we just don't understand what makes it a rope rather than a dish.”

Perhaps magnetic fields hold it in place, the researchers say. Maybe “shepherding planets” are reining it in like several of Saturn’s moons control certain planetary rings.

“What makes this star so special is its very strong magnetic field and the fact that it rotates extremely slow compared to other stars of the same type,” said Swetlana Hubrig, of the Leibniz Institute for Astrophysics Potsdam (AIP), Germany.

The star’s unique properties first caught the researchers’ attention in 2008, and they have been studying it intensely ever since.

Understanding the interaction between central stars, their magnetic fields, and planet-forming disks is crucial for astronomers to reconstruct the solar system's history.

It is also important to account for the diversity of the known planetary systems beyond our own. This new finding raises more questions than it answers about the late stages of star and solar system formation.

“Why do turbulent motions not tear the ring apart?” Cowley wondered. “How permanent is the structure? What forces might act to preserve it for times comparable to the stellar formation time itself?”

The team is excited to have found an ideal test case to study this type of object.

“This star is a gift of nature,” Hubrig said.

The findings are newly published online in Astronomy and Astrophysics. The paper is titled “The narrow, inner CO ring around the magnetic Herbig Ae star HD 101412.”

Authors are from the University of Michigan, the Leibniz Institute for Astrophysics Potsdam (AIP) in Germany, the Istituto Nazionale die Astrofisica in Italy and the European Southern Observatory.

ESA ESO: The Helix in New Colours

ESO’s VISTA telescope, at the Paranal Observatory in Chile, has captured a striking new image of the Helix Nebula. 

This picture, taken in infrared light, reveals strands of cold nebular gas that are invisible in images taken in visible light, as well as bringing to light a rich background of stars and galaxies.

The Helix Nebula is one of the closest and most remarkable examples of a planetary nebula.

It lies in the constellation of Aquarius (The Water Bearer), about 700 light-years away from Earth.

This strange object formed when a star like the Sun was in the final stages of its life.

Unable to hold onto its outer layers, the star slowly shed shells of gas that became the nebula. It is evolving to become a white dwarf star and appears as the tiny blue dot seen at the centre of the image.

The nebula itself is a complex object composed of dust, ionised material as well as molecular gas, arrayed in a beautiful and intricate flower-like pattern and glowing in the fierce glare of ultraviolet light from the central hot star.

The main ring of the Helix is about two light-years across, roughly half the distance between the Sun and the nearest star. However, material from the nebula spreads out from the star to at least four light-years.

This is particularly clear in this infrared view since red molecular gas can be seen across much of the image.

While hard to see visually, the glow from the thinly spread gas is easily captured by VISTA’s special detectors, which are very sensitive to infrared light.

The 4.1-metre telescope is also able to detect an impressive array of background stars and galaxies.

The powerful vision of ESO’s VISTA telescope also reveals fine structure in the nebula’s rings. The infrared light picks out how the cooler, molecular gas is organised.

The material clumps into filaments that radiate out from the centre and the whole view resembles a celestial firework display.

Even though they look tiny, these strands of molecular hydrogen, known as cometary knots, are about the size of our Solar System.

The molecules in them are able to survive the high-energy radiation that emanates from the dying star precisely because they clump into these knots, which in turn are shielded by dust and molecular gas. It is currently unclear how the cometary knots may have originated.

Svalbard's Frozen antenna field sounding out the Tropopause

(Image: Vincent Fournier)

Svalbard - the most northerly outpost of Norway and home to some 3000 polar bears - is an isolated group of glacier-covered islands deep within the Arctic Circle.

As we know only too well, glaciers haven't been faring well in recent years.

But it isn't the state of the ice that is being monitored here.

Instead, the vital climate change research being carried out is aimed high in the sky, to the mysterious region of the atmosphere known as the tropopause.


Stand on the surface of the Earth and your head is in the troposphere. Near the poles the troposphere is at its thinnest: about 9 kilometres thick. At the equator it is more like 17 kilometres.

Above it is the stratosphere, and at the intersection between the two is the tropopause.

Monitoring the region is the SOUSY Svalbard Radar (SSR), an array of 96 Yagi-UDA antennas in Adventdalen on Spitsbergen Island, shown in the photo.  

SOUSY stands for sounding system: its job is to sound out the activity of the atmosphere, by measuring phenomena such as gravity waves and air turbulence.

We need to know what the tropopause is doing because greenhouse gases have very different effects above and below it.

"While increasing greenhouse gas concentrations contribute to warming the troposphere, the very same gases diffuse into the middle atmosphere where they act as refrigerants and therefore cause 'global cooling'," says Chris Hall of the University of Tromsø, Norway, who works on the SSR.

Since the altitude of the tropopause is affected both by warming from below and cooling from above it is particularly sensitive to radiative forcing, the amount of solar energy trapped in the atmosphere.

"The SOUSY radar monitors parameters such as tropopause height 24/7," says Hall. "A long-enough time series built up by this instrument helps us monitor and understand climate change in new ways."

Purple Haze: Dumbbell Nebula

A purple glow seems to burst out of space in this stunning image of a cosmic gas cloud by skywatcher Bill Snyder.

The photo depicts the Dumbbell Nebula, also known as M27, seen near the constellation of Vulpecula or "Little Fox."

M27 is a planetary nebula. This is a type of emission nebula that forms when a star dies and emits a glowing shell of gas. In the distant future — more than 6 billion hers from now — our sun will likely puff off its outer layers to create a planetary nebula.

In the photo, the nebula shines in two bright colors: The purple central glow is surrounded by a blue, hazy halo. These hues are due to hyrdogen and oxygen gas that has been ejected from the star out into space.

This nebula is more than 1,200 light-years away (a light-year is the distance light travels in one year — about 6 trillion miles, or 10 trillion kilometers). For avid skywatchers, the nebula can be easily seen through an amateur telescope, and has an apparent magnitude of 7.5. On this scale, smaller numbers represent brighter objects. The dimmest objects visible to the human eye are about magnitude 6.5.

Jupiter's Eroding Core: Large Exoplanets Have no Cores

A new study indicates that the hydrogen and helium gases that made Jupiter a gas giant are destroying the planet's very core, leading astronomers to believe that most massive extrasolar planets have no cores at all and changing the view scientists have long held of these distant worlds.

Jupiter has been called a gas giant because it consists mostly of hydrogen and helium surrounding a central core of iron, rock, and ice.

The core, which weighs roughly 10 times as much as Earth, is a small component in a planet that weighs 318 Earths.

These same gases are causing the solid rock in Jupiter's core to dissolve into liquid, the researchers said.

Planetary scientists Hugh Wilson and Burkhard Militzer of the University of California, Berkeley, performed quantum mechanical calculations on the outcome if magnesium oxide (MgO), which is a key ingredient in the rock of Jupiter's core, is submerged in a hydrogen-helium fluid at the planet's heart.

According to the researchers, with MgOs high solubility, the core's temperature, which is hotter than the sun at approximately 16,000 degrees Kelvin, will make the solid rock in Jupiter's core melt into liquid.

In a paper submitted to Physical Review Letters, the scientists said that although the exact rate of erosion is unknown, it is also calculated that the ice in the core also dissolves, so Jupiter's present core may not be as large as it was when the planet formed.

While the new findings are important, a planetary scientist, Jonathan Fortney, said the big question is whether the convection in Jupiter's interior is vigorous enough to dredge up dissolved core material and toss it into the hydrogen-helium envelope.

Fortney said that if this was the case, then Jupiter's core could be smaller today than it was at birth; if not, the dissolved rock and ice will simply remain at Jupiter's center although the boundary between the core and mantle may not be so distinct.

"I think we've made much more progress in the past year than people had made in the previous 20 years," said Fortney, adding that those calculations have implications far beyond Jupiter since many of the planets orbiting other stars are more massive than Jupiter, so their cores are even hotter.

"For these planets, core erosion would be faster," says Militzer, which could support the theory that gas giants several times heavier than Jupiter might be completely coreless.

In 2016, NASA's Juno spacecraft will start orbiting Jupiter, which could provide data on the planet's interior by measuring its gravitational field.

Sharpless 2-106: The Snow Angel

The bipolar star-forming region, called Sharpless 2-106, looks like a soaring, celestial snow angel.

The outstretched "wings" of the nebula record the contrasting imprint of heat and motion against the backdrop of a colder medium.

Twin lobes of super-hot gas, glowing blue in this image, stretch outward from the central star. 

This hot gas creates the "wings" of our angel. 

A ring of dust and gas orbiting the star acts like a belt, cinching the expanding nebula into an "hourglass" shape.

Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

NASA Chandra X-ray Image: Abell 2052 Galaxy Cluster Sloshes cosmic gas

Like wine in a glass, vast clouds of hot gas are sloshing back and forth in Abell 2052, a galaxy cluster located about 480 million light years from Earth.

X-ray data (blue) from NASA's Chandra X-ray Observatory shows the hot gas in this dynamic system, and optical data (gold) from the Very Large Telescope shows the galaxies.

The hot, X-ray bright gas has an average temperature of about 30 million degrees.

A huge spiral structure in the hot gas, spanning almost a million light years, is seen around the outside of the image, surrounding a giant elliptical galaxy at the center.

This spiral was created when a small cluster of galaxies smashed into a larger one that surrounds the central elliptical galaxy.

The smaller cluster passed the cluster core, the direction of motion of the cluster gas reversed and it travelled back towards the cluster centre.

The cluster gas moved through the centre again and "sloshed" back and forth, similar to wine sloshing in a glass that was jerked sideways.

The sloshing gas ended up in a spiral pattern because the collision between the two clusters was off-center.

The Chandra data show clear bubbles evacuated by material blasted away from the black hole, which are surrounded by dense, bright, cool rims.

As with the sloshing, this activity helps prevent cooling of the gas in the cluster's core, setting limits on the growth of the giant elliptical galaxy and its supermassive black hole.

Image Credit: X-ray: NASA/CXC/BU/L.Blanton; Optical: ESO/VLT

Disaster looms for gas cloud falling into Milky Way's central black hole

This view shows a simulation of how a gas cloud that has been observed approaching the supermassive black hole at the center of the galaxy may break apart over the next few years.

This is the first time ever that the approach of such a doomed cloud to a supermassive black hole has been observed and it is expected to break up completely during 2013.

The remains of the gas cloud are shown in red and yellow, with the cloud's orbit marked in red. The stars orbiting the black hole are also shown along with blue lines marking their orbits. This view simulates the expected positions of the stars and gas cloud in the year 2021. Credit: ESO/MPE/Marc Schartmann

The normally quiet neighbourhood around the massive black hole at the center of our Milky Way Galaxy is being invaded by a gas cloud that is destined in just a few years to be ripped, shredded and largely eaten.

Many, if not all, galaxies have massive black holes at their centers. But this supermassive black hole is the only one close enough for astronomers to study in detail, so the violent encounter is a unique chance to observe what until now has only been theorised: how a black hole gulps gas, dust and stars as it grows ever bigger.

"When we look at the black holes in the centers of other galaxies, we see them get bright and then fade, but we never know what is actually happening," said Eliot Quataert, a theoretical astrophysicist and University of California, Berkeley professor of astronomy.

"This is an unprecedented opportunity to obtain unique observations and insight into the processes that go on as gas falls into a black hole, heats up and emits light. It's a neat window onto a black hole that's actually capturing gas as it spirals in."

"The next two years will be very interesting and should provide us with extremely valuable information on the behaviour of matter around such massive objects, and its ultimate fate," said Reinhard Genzel, professor of physics at both UC Berkeley and the Max Planck Institute for Extraterrestrial Physics (MPE) in Garching, Germany.

The discovery by Genzel; Stefan Gillessen of the MPE; Quataert and colleagues from Germany, Chile and Illinois will be reported online Wednesday, Dec. 14, in advance of the Jan. 5 publication of the news in the British journal Nature.

Astronomers Find ‘Pristine’ Gas Formed Minutes After Big Bang

Astronomers have discovered two clouds of gas in the same state as they were in just moments after the Big Bang.

Unlike everything else in the universe, the two clouds never combined with elements that were later formed in stars.

Instead, each consists only of the light elements that occurred in the Big Bang some 14 billion years ago.

Nuclear reactions created the three lightest elements - hydrogen, helium, and a tiny amount of lithium - which stars then converted into heavier elements such as carbon and oxygen.

This new discovery is the first time astronomers have found a star or cloud made solely of these three lighter elements. All known stars and gas clouds contain at least a small amount of "metals", the term astronomers use to describe any element that is heavier than helium, including oxygen and carbon.

"As hard as we've tried to find pristine material in the universe, we have failed until now," says J Xavier Prochaska, professor of astronomy and astrophysics at the University of California, Santa Cruz.

"This is the first time we've observed pristine gas uncontaminated by heavier elements from stars."

"It's quite exciting, because it's the first evidence that fully matches the composition of the primordial gas predicted by the big bang theory," says Michele Fumagalli of the University of California, Santa Cruz, lead author of a paper on the findings published online in Science today.

"Their chemical composition is unusual," says Fumagalli. "This gas is of primordial composition, as it was produced during the first few minutes after the Big Bang."

The researchers discovered the clouds of gas using the HIRES spectrometer on the Keck I Telescope at the M Keck Observatory in Hawaii.

Previously, the lowest abundances of metals in the universe were around one-thousandth of the sun's "metallicity." At the other end of the scale, stars and gas with the highest metallicities are almost ten times that of the sun.

Fighting Dragons of Ara

Fighting Dragons of Ara (NGC 6188 and 6164) by Michael Sidoni.

Clouds of swirling purple, green and orange gas and dust that appear as ‘fighting dragons’, shaped by the recent birth of large stars much bigger and brighter than our Sun.

One such star can be seen to the lower left of the image within two shells of glowing gas.

The image gives a snapshot of the chaotic stellar nurseries in which stars are born.

Our own Sun probably formed in similar circumstances 4.5 billion years ago.

Picture: Michael Sidonio

ESA Proba-2: Ffuel tank refilled from ‘solid gas’

Proba-2 is flight-testing a total of 17 technology demonstrators for future ESA missions. 

It also serves as a scientific platform for solar and space weather observations.

Credits: ESA/Pierre Carril

Sometimes all it takes is fresh air to get a new lease of life. ESA’s Proba-2 microsatellite is a good example: an influx of nitrogen has replenished its fuel tank, in the process demonstrating a whole new space technology.

On 16 August a telecommand was sent from ESA’s Redu ground station in Belgium to boost the gases in Proba-2’s unusual ‘resistojet’ engine.

Used to maintain the microsatellite’s orbit at 600 km altitude, this experimental engine runs on xenon gas heated before ejection to provide added thrust.

The command added nitrogen gas to the fuel tank, bringing its pressure close to its launch level.

	cool-gas generators

“What makes this repressurisation unique is that the added gas was not stored in a pressurised state but produced from a solid material at room temperature, the first of four ‘cool-gas generators’ on Proba-2,” explained Laurens van Vliet of Dutch research organisation TNO, which developed the technology.

“Nitrogen, like xenon, is an inert, non-reactive gas, so the resistojet can work just as well with a xenon–nitrogen mixture.”

The bottle-shaped cool-gas generators are filled with a rigid solid material that, once triggered, produces more than 250 times its own volume in pure nitrogen gas.

Integrating TNO's four cool-gas generators aboard Proba-2

Credits: TNO

To read more on this subject visit the ESA Proba-2 portal

NASA Scientists Cook Up Jupiter's Atmosphere on Earth

Close-up of Jupiter's Great Red Spot as seen by a Voyager spacecraft.
CREDIT: NASA/JPL-Caltech

On a rooftop in downtown Atlanta, a group of scientists are cooking up alien atmospheres.

Their results will help astronomers understand the data that NASA's Juno spacecraft will send back from Jupiter in 2016.

Jupiter's cloudy bands and great red spot are visible with an amateur telescope but the elements that compose them are more challenging to detect.

The Juno spacecraft launched on Aug. 5, will spend the next five years journeying to Jupiter, the largest planet in the solar system.

Using myriad instruments, the craft is expected to help scientists come to a greater understanding of the origins and composition of the gas giant.

Photos: NASA's Juno Mission to Jupiter

Mercury vapour released from broken energy saving light bulbs can exceed safe exposure levels

Once broken, a compact fluorescent light bulb (CFL) or energy saving light bulbs continuously releases mercury vapour into the air for weeks to months, and the total amount can exceed safe human exposure levels in a poorly ventilated room, according to study results reported in Environmental Engineering Science, a peer-reviewed online only journal published monthly by Mary Ann Liebert, Inc.

The amount of liquid mercury (Hg) that leaches from a broken compact fluorescent lamp (CFL) is lower than the level allowed by the U.S. Environmental Protection Agency (EPA), so CFLs are not considered hazardous waste.

However, Yadong Li and Li Jin, Jackson State University (Jackson, MS) report that the total amount of Hg vapour released from a broken CFL over time can be higher than the amount considered safe for human exposure.

They document their findings in the article "Environmental Release of Mercury from Broken Compact Fluorescent Lamps."

As people can readily inhale vapour-phase mercury, the authors suggest rapid removal of broken CFLs and adequate ventilation, as well as suitable packaging to minimize the risk of breakage of CFLs and to retain Hg vapour if they do break, thereby limiting human exposure.

Tests of eight different brands of CFLs and four different wattages revealed that Hg content varies significantly from brand to brand. To determine the amount of Hg released by a broken CFL, Li and Jin used standard procedures developed by the EPA to measure leaching of mercury in liquids and used an emission monitoring system to detect Hg vapour.

"This paper is a very nice holistic analysis of potential risks associated with mercury release from broken CFLs and points to potential human health threats that have not always been considered," according to Domenico Grasso, PhD, Editor-in-Chief and Vice President for Research, Dean of the Graduate College, University of Vermont (Burlington).

Socially Awkward Robotic Blimp Stalks People

Meet Ollie, the DIY autonomous robotic blimp. He (yes, the blimp is apparently a "he") floats on Helium; has flapping wings made of wire, mylar, and servos; and he reacts to his surroundings--often socially awkwardly.

Created by Pritika Nilaratna, a user experience designer and programmer in New York City, Ollie floats around and tries to get attention from people. He is observant and reacts to voices by "excitedly flapping his wings. Ollie is meant to be friendly and eager to be noticed, but also unobtrusive--you could just just push him out of your way if he gets annoying.

In the video of Ollie below, you see that he actually kind of stalks people to get their attention. According to Pritikia "machine-human interaction has the potential to be both poetic and ubiquitous," and Ollie "is a demonstration of the creative capabilities of robots as inhabitants of our society, breaking the stereotype of the servile robot." In other words, Ollie is meant to break the standard that we're so used to. It's definitely funny watching some people's responses to Ollie.


Ollie from Pritika Nilaratna on Vimeo.

So how do you get your own? You make it! Ollie is under a Creative Commons Attribution-ShareAlike 3.0 Unported License which means that you can copy and modify Ollie's design so long as you give credit to the author (Pritika) and that you only distribute the resulting work under the same kind or similar license.

You can make your very own Ollie with an Arduino board, some servos, a mylar balloon envelope, and some other basic electronics supplies. Pritika posted instructions for Ollie on the main Ollie site and also as an Instructables project. To learn more about Ollie check out the abstract.
[Ollie via Hackaday / Video: Pritika Nilaratna (at Vimeo)]

Gas-powered diesel engine may double fuel efficiency

Recently, it seems like car engine innovation has become about moving away from the internal combustion engine and toward more environmentally-friendly alternatives like electric motors.

Unfortunately, the truth is gasoline engines, which have been with us for well over a century, aren’t headed for the junk yard any time soon.

With that in mind, engineers at the U.S. Department of Energy’s Argonne National Laboratory have been hard at work on a project to improve the fuel efficiency of gas-powered engines.

Their approach has been to figure out a way to take advantage of the highly fuel efficient technologies found in diesel engine while also keeping harmful emissions to a minimum.

So far, the result is a gas-powered prototype that’s cleaner than a diesel engine and almost twice as efficient as a typical gasoline-powered engine.

The major difference between gas and diesel engines is the technology used to ignite the fuel. Gasoline engines are designed to mix air with the fuel prior to compressing and igniting the mixture. But in a diesel engine, the air is compressed first and then the fuel is injected.

This makes it so the air is hot enough to ignite the fuel without spark plugs or the use of an air-restricting throttle, which allows the fuel to mix more evenly with air so that more of can be burned.

The drawback is that the process produces unacceptably high levels of nitrous oxides and soot. This is because diesel fuel is so easy to auto-ignite that it begins to react the moment it’s introduced—long before all of the fuel is in the chamber.

Nitrous oxides are created when the flame jet created by the diesel injection burns so hot that nearby nitrogen and oxygen molecules in the air start to break apart and react. Meanwhile, soot is created inside the hot jet because the fuel doesn’t have enough oxygen to fully burn, creating soot instead.

“What we want to do is combine the efficiency of diesel with the cleanliness of gas,” said Steve Ciatti, an engineer working on the project. “So we lose the throttle and spark plugs, because those create inefficiencies. We start with a diesel engine and inject gasoline instead.