Scientists discover ancient solar system hosting five Earth-sized planets

Artist's impression of the ancient solar system (Image: Tiago Campante/Peter Devine)

A team led by scientists from the University of Birmingham, UK, have discovered an ancient solar system dating back to the dawn of the Milky Way. What makes the system truly fascinating is the confirmed existence of five Earth-sized planets, which may have profound implications for the presence of ancient life existing from an early point in our galaxy's 13.8 billion year history.

The team discovered the system by analyzing data returned by NASA's Keplar space telescope. The five exoplanets were detected by observing the telltale dip in light emanating from the parent star that is indicative of a planetary body passing across its parent's stellar disk. From these light readings, the scientists were able to determine the planets' approximate sizes.

The age of Kepler-444 was determined via a technique known as asteroseismology, whereby astronomers detect oscillations taking place within the parent star, caused by sound trapped inside the stellar giant. These oscillations manifest themselves by shifts and sudden pulses of brightness that can be observed and used to characterize the fiery subject.

Using this method, the team approximates that Kepler-444 formed roughly 11.2 billion years ago, when the universe was only 20 percent its current age. Furthermore, astronomers believe that the five planets orbiting the distant star were already older than the Earth is now (4.54 billion years) by the time our planet began to form. This makes it the oldest solar system with terrestrial-sized bodies found to date.

The discovery has the potential to greatly impact current theories regarding ancient life in our galaxy. We now know that Earth-like planets were being created from very early on in our galaxy's lifespan, increasing the chances for the formation of ancient life. Further observation of the system will provide valuable insights into one of the earliest instances of planetary and moon formation in the galaxy.

A paper detailing the team's findings has been published in The Astrophysical Journal.

post from sitemap

New technique uses most abundant gas on Earth to help create bioethanol

Nitrogen gas promises a quicker, cheaper, cleaner way to increase production in bioethanol-producing microbes (Photo: Indiana University)

Zymomonas mobilis bacterium might be tricky to say, but this bioethanol-producing microbe could become a household name if Indiana University (IU) biologists have their way. The biologists claim to have found a quicker, cheaper, cleaner way to increase bioethanol production in this microorganism by using the most abundant element in the Earth’s atmosphere: nitrogen gas (N₂). By replacing chemical fertilizers with N₂, production costs could be slashed and cellulose ethanol derived from wood pulp made much more economically viable – so much so that the researchers believe it may compete with corn ethanol and gasoline on price.

Cellulose found in woody plants such as trees, grasses, and other inedible plant substances – like olive stones – is generally low in nitrogen, which makes cellulose all that much more difficult to convert given that nitrogen is a staple requirement for feeding ethanol-producing microbes. As a result, cellulosic ethanol makers spend many millions of dollars a year on nitrogen-rich fertilizers such as diammonium phosphate or corn-steep liquor.

Zymomonas mobilis bacterium uses nitrogen gas to help produce cleaner, more abundant bioethanol (Photo: Indiana University)

In an unexpected outcome, an IU team led by biologist Dr James B. McKinlay inadvertently happened upon a possible solution to this problem when they experimented with the effects of nitrogen gas on the Zymomonas mobilis bacterium.

"When we discovered that Z. mobilis could use N₂, we expected that it would make less ethanol. N₂, utilization and ethanol production demand similar resources within the bacterial cell so we expected resources to be pulled away from ethanol production to allow the bacteria to grow with N₂," said Doctor McKinlay. "To our surprise the ethanol yield was unchanged when the bacteria used N₂, In fact, under certain conditions, the bacteria converted sugars to ethanol much faster when they were fed N₂."

Quickly realizing that the bacterium was able to use N₂ without affecting the production of ethanol, the scientists reasoned that nitrogen gas may serve as a far cheaper replacement for nitrogen fertilizers used in the creation of cellulosic ethanol.

“Until recently, ethanol has been produced almost entirely from food crops, but last year there was a surge in cellulosic ethanol production as several commercial facilities opened,” said Dr McKinlay. “Cellulosic ethanol offers more favorable land use and lower carbon emissions than conventional ethanol production. Even so, cellulosic ethanol is struggling to be cost-competitive against corn ethanol and gasoline.”

The researchers also noted that while the largest costs in cellulosic ethanol production are the biomass and the enzymes required to breakdown the plant matter into sugars, the enormous amounts of nitrogen-rich chemical fertilizers used in the fermentation vats of biofuel producers to improve yield are also represent a significant and on-going cost.

As a result, the scientists estimate that using N₂ in place of solid nitrogen-enriched fertilizer could help save an average cellulosic ethanol production plant somewhere in the region of a million dollars a year. Added to the fact that the N₂ could easily be produced at the facility, there would also be a potential reduction in transportation costs, and a lowering of greenhouse gas emissions.

“More work needs to be done to assess how this approach can be integrated and optimized on an industrial scale, but all of the data we’ve collected thus far are very encouraging,” said Dr McKinlay.

The work has resulted in a provisional patent being filed with the United States Patent and Trademark Office. The research was published in the journal Proceedings of the National Academy of Sciences.

post from sitemap

DJI firmware update makes the White House a drone no-fly zone

DJI has announced a new firmware update that disables drones flying within a 15.5 mile (25 km) radius of the White House (Photo: Ben Coxworth/Gizmag.com)

Following the crash-landing of a drone on the grounds of the White House last week, the Chinese manufacturer of said drone, DJI, has released new firmware to prevent overzealous pilots flying UAVs anywhere near 1600 Pennsylvania Avenue. Available to download now for owners of the company's popular Phantom 2 drones, the update signals a willingness from the company to work with regulators to clear the air for safer drone flight.

With more and more UAVs finding their way into the hands of hobbyists, commercial operators, and government employees who have enjoyed a drink or two, ensuring the aircraft don't come into contact with planes, presidential palaces and anything else to which they may pose a threat is critical to public safety and ultimately, their widespread adoption.

To this end, the Federal Aviation Administration (FAA) has a set of rules in place designed to promote safer use. These include flying the drone within the pilot's line of site, not flying higher than 400 ft (122 m), keeping clear of manned aircraft and notifying airports or control towers if flying within 5 miles (8 km).

But these regulations won't be all that easy to enforce. So rather than relying on the goodwill of its customers to straighten up and fly right, DJI is turning to software to make sure its products aren't caught up in any illegal activity.

The new firmware update is for owners of the Phantom 2, Phantom 2 Vision and Phantom 2 Vision + and integrates a no-fly zone over the White House and a 15.5 mile (25 km) radius around it.

DJI has taken a proactive approach to integrating safety precautions into its Phantom drones. In April last year it announced a flight limitation system, which works with flight agencies and GPS to determine no-fly zones around the world's airports. Simply put, if your Phantom drone has a strong enough GPS signal and you are within a certain distance of an airport, you won't be able to take off.

At present, DJI says it is continuing to update its no-fly zone list, claiming "sensitive institutions and national borders" to be in its sights. This may well be in response to a drone loaded with crystal meth crashing down near the US-Mexico border last month.

These efforts to allay common safety concerns are a smart move from DJI, already a dominant figure in the consumer drone market. Pre-empting the risks, both potential and real, should help to appease the FAA and usher in the adoption of UAVs, and probably won't do the company's market share any harm either.

post from sitemap

Scientists discover a "mini-brain" in spinal cord that helps keep us balanced

Scientists have mapped a cluster of neurons that aid our understanding of what keeps us from falling over (Image: Steeve Bourane/Salk Institute for Biological Studies)

Keeping ourselves upright is something most of us shouldn't need to think a whole lot about, given we've been doing it almost our entire lives. But when it comes to dealing with more precarious terrain, like walking on ice or some sort of tight rope, you might think some pretty significant concentration is required. But researchers have found that even in our moments of great instability, our subconsciousness is largely responsible for keeping us from landing on our backsides. This is due to what scientists are describing as a mini-brain, a newly mapped bunch of neurons in the spinal cord which processes sensory information and could lead to new treatment for ailing motor skills and balance.

"How the brain creates a sensory percept and turns it into an action is one of the central questions in neuroscience," says Martin Goulding, senior author of the research paper and professor at the Salk Institute. "Our work is offering a really robust view of neural pathways and processes that underlie the control of movement and how the body senses its environment. We’re at the beginning of a real sea change in the field, which is tremendously exciting.”

The work of Goulding and his team focuses on how the body processes light touch, in particular the sensors in our feet that detect changes in the surface underfoot and trigger a reaction from the body.

"Our study opens what was essentially a black box, as up until now we didn’t know how these signals are encoded or processed in the spinal cord," says Gould. "Moreover, it was unclear how this touch information was merged with other sensory information to control movement and posture."

Gould is referring to the numerous sources from which our brains gather information to keep us upright. Signals from our eyeballs will tell us a surface may be slippery, sensors in our ears keep our head level, while signals come from our arms and legs to keep everything in synch. Scientists have believed that the signals coming from light touch sensors are processed by neural circuits in the spinal cord, but until now have been unable to determine the intricacies of this complex system.

Working with mice, Goulding's team employed advanced imaging techniques to track nerve fibers that carry the signals as they travel from light touch sensors in the feet to the spinal cord. What they found was that the fibers connected with a group of neurons called RORα neurons, which are also connected with the motor region of the brain.

Genetically modifying the mice so that the RORα neurons were disabled led to a significant loss in sensitivity in their skin, though they were still capable of walking and keeping their balance on flat ground. But when the team led the animals to walk across a narrow beam the difference became clear, with regular mice performing much better than the clumsy rodents whose RORα neurons were disabled.

The scientists say the difference between the two groups of mice was an ability to sense when they were slipping off the beam and correct their footing. They believe this corresponds with the ability to keep one's balance on slippery surfaces.

And because the RORα neurons also connect with neurons in the ventral spinal cord that control movement, the team says they are at the core of a so-called mini-brain: a cluster of neurons in the spinal cord that integrates signals from the brain with sensory signals and moves limbs accordingly.

"We think these neurons are responsible for combining all of this information to tell the feet how to move," says Steeve Bourane, a postdoctoral researcher in Goulding’s lab. "If you stand on a slippery surface for a long time, you’ll notice your calf muscles get stiff, but you may not have noticed you were using them. Your body is on autopilot, constantly making subtle corrections while freeing you to attend to other higher-level tasks."

The researchers say that improving our understanding of these circuits should help in the development of therapies for spinal cord injuries and conditions that hamper motor skills and balance.

The team's research was published in the journal Cell.

post from sitemap

ESA abandons comet lander search

Sequence of images taken by Rosetta as Philae descended to the comet surface (Image: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)

After months of searching, the Euopean Space Agency (ESA) has given up the hunt for the lost Philae comet lander. Despite having narrowed the final resting place of the unmanned probe to a "landing strip" measuring 350 x 30 m (1,150 x 100 ft) on comet 67P/Churyumov-Gerasimenko, the space agency has been unable to locate it and has commanded the Rosetta spacecraft to move into a higher orbit as it continues its science mission.

The Philae lander was the first manmade object to attempt a soft landing on a comet. On November 12, 2014, the lander made contact with the surface of 67P, but due to a malfunction in its landing systems it was unable to anchor itself. As a result, it rebounded four times before finally coming to rest at an unlocated site called Abydos.

Unfortunately, the spacecraft landed on its side next to a crater or cliff wall, where not enough sunlight could reach its solar panels and provide power. After 60 hours, the batteries went dead and Philae went into hibernation.

Since then, ESA has been trying to locate Philae from images taken during the descent, and by sending Rosetta over the suspected landing area at an altitude of 18 to 28 km (11 to 17 mi). Each pass was timed to coincide with the 1.3 hours per comet revolution that the lander was illuminated. However, the timing was also when the area was marked by long shadows and though Rosetta's instruments did narrow down the search area, the exact final resting place of Philae remains a mystery.

Rosetta has now moved into a new orbit as it continues its mission. This is farther out and provides fewer opportunities for looking for Philae. At its current distance, the resolution is so low that the lander would appear as three dots – and on a surface strewn with craters and boulders that's very easy to lose in the background. Also, the mission schedule means that future searches will be opportunistic.

Lander search area (Image: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)

“Rosetta’s busy science schedule is planned several months in advance, so a dedicated Philae search campaign was not built into the plan for the close flyby,” says ESA’s Rosetta project scientist Matt Taylor. “We’ll be focusing on “co-riding” observations from now on, that is, we won’t be changing the trajectory of Rosetta to specifically fly over the predicted landing zone in a dedicated search, but we can modify the spacecraft pointing and/or command images to be taken of the region if we’re flying close to the region and the science operations timeline allows.”

ESA's main hope is that as 67P draws closer to the Sun enough light will reach Philae to generate enough power to send back a signal. However, this depends on exactly how much light the probe receives during each comet "day," the effects of the gas and dust jetting out of the comet as the Sun heats it, and the effect of the cold on the spacecraft's electronics during hibernation. The space agency points out it won't be until late March that the environment is warm enough to allow a reboot and it may be as late as June before the Sun is strong enough to generate the 17 Watts needed. However, engineers remain optimistic that if Philae can recover, it could be capable of resuming experiments as the comet approaches perihelion.

post from sitemap