NASA and ATK Successfully Test Five-Segment Solid Rocket Motor

With a loud roar and mighty column of flame, NASA and ATK Aerospace Systems successfully completed a two-minute, full-scale test of the largest and most powerful solid rocket motor designed for flight. The motor is potentially transferable to future heavy-lift launch vehicle designs.

Ignition of Development Motor-2 during testing. Credit: NASA

The stationary firing of the first-stage development solid rocket motor, dubbed DM-2, was conducted by ATK, a division of Alliant Techsystems of Brigham City, Utah. DM-2 is the most heavily instrumented solid rocket motor in NASA history, with a total of 53 test objectives measured through more than 760 instruments.

Prior to the static test, the solid rocket motor was cooled to 40 degrees Fahrenheit to verify the performance of new materials and assess motor performance at low temperatures during the full-duration test. Initial test data showed the motor performance met all expectations.

“For every few degrees the temperature rises, solid propellant burns slightly faster and only through robust ground testing can we understand how material and motor performance is impacted by different operating conditions,” said Alex Priskos, first stage manager for Ares Projects at NASA’s Marshall Space Flight Center in Huntsville, Ala. “Ground-testing at temperature extremes pushes this system to its limits, which advances our understanding of five-segment solid rocket motor performance.”

The first-stage solid rocket motor is designed to generate up to 3.6-million pounds of thrust at launch. Information collected from this test, together with data from the first development motor test last year, will be evaluated to better understand the performance and reliability of the design.

Although similar to the solid rocket boosters that help power the space shuttle to orbit, the five-segment development motor includes several upgrades and technology improvements implemented by NASA and ATK engineers. Motor upgrades from a shuttle booster include the addition of a fifth segment, a larger nozzle throat, and upgraded insulation and liner. The motor cases are flight-proven hardware used on shuttle launches for more than three decades. The cases used in this ground test have collectively launched 59 previous missions.

After more testing, the first-stage solid rocket motor will be certified to fly at temperature ranges between 40-90 degrees Fahrenheit. The solid rocket motor was built as an element of NASA’s Constellation Program and is managed by the Ares Projects Office at Marshall. ATK Aerospace Systems is the prime contractor.

Japanese researchers create smell sensor using genetically engineered frog eggs

A University of Tokyo group of researchers, led by bioengineer Shoji Takeuchi, have made an electronic sensor capable of smelling gases. The sensor uses genetically engineered frog cells. Since previous sensors were not very accurate, the scientist decided to try a biological approach. The invention was revealed in a US scientific journal yesterday, and is supposed to be used to design better machines to detect polluting gases in the atmosphere.

Previous smell sensors were based on quartz rods, which vibrate when a substance binds to them. The gases are distinguished by their molar masses, which can be similar for molecules with different structure, thus relatively often triggering a false positive. Trying to find a more accurate solution, Takeuchi decided to follow an example from insect world. As he explained, “when you think about the mosquito, it is able to find people because of carbon dioxide from the human. So the mosquito has CO2 receptors. When we can (extract) DNA (from the mosquito) we can put this DNA into the frog eggs to detect CO2.”

Two African clawed frogs Xenopus laevis. Image: TimVickers.

Genes of several insects (the silk moth, diamondback moth and fruit fly), injected into African clawed frog Xenopus laevis eggs, allowed them to produce relatively inexpensive and useful sensors. The choice of the species was caused by their widely studied and well-understood protein expression mechanism.

The modified cells responded to three kinds of pheromones and one odourant, which have similar chemical properties. When a molecule of an odorous substance adhered to the receptor on the membrane protein, ion channels opened for a certain period of time, and a current was generated. Its magnitude was clearly different for all four tested substances, allowing to distinguish between them accurately.

The colleagues embedded the sensor into a mannequin, so that it could shake its head when a gas was detected. It was easier to observe. Pheromones and molecules with quite similar molecule structure produced clearly distinguishable reaction, with higher accuracy than other biological or human-made sensors. As the research group said, the detection sensitivity of the odor sensor is several tens of parts per billion (ppb), and it is as high as the sensitivity of an existing odor sensor that uses an oxide semiconductor. The distinctive feature of the new sensor is its capability to selectively detect some odorous substances, rather than its sensitivity. Very few false positives were possible due to the biological mechanism involved.

At normal temperature, the sensor lifetime is about 12 hours, which can be extended by putting it into a refrigerator before first use.

Shoji Takeuchi says has a great hope for research use in future, since the frog eggs are very practical for genetic engineering, and can be conveniently used to develop smell sensors for a wide range of gases. He said, “The X. laevis oocyte has high versatility for the development of chemical sensors for various odorants. We believe that a shared ability to smell might open a new relationship between man and robot. .. The research will have wide implications… If the sensor is embedded in a nursing robot, it will be able to identify certain mouth odors or body odors. Also, it can be used for detecting CO2, air pollution, water pollution and food. It’s very important for the environment.”

Mount Sinabung erupts in Sumatra, Indonesia

Mount Sinabung has erupted in Sumatra, Indonesia, spitting smoke and ash 1,500 meters (4,921.3 ft) in the air at 00:08 local time Sunday.

Sinabung has been long dormant for over 400 years and it has been spewing smoke since Friday, according to residents (pictured 1987). Image: Tom Casadevall, USGS.

Surono of Indonesia’s Directorate of Vulcanology said, “Initially we thought the ash and smoke were triggered by rain but now we know the driving pressure was from magma. It’s clearly dangerous so we’ve raised the warning to the highest level, or red level.”

“The situation is under control. Emergency response teams are already on the scene,” says a spokesperson for the Indonesian National Disaster Management Agency.

Saturday, Sinabung was spewing smoke, however, the volcano was not expected to erupt, according to the directorate.

Around 12,000 residents have been evacuated from the area. One person has died.

This is the first reported eruption since 1600.

UK scientists discover multiple antibiotics used by fungus-farming ants to protect colonies

University of East Anglia researchers led by Dr Matt Hutchings have discovered that leafcutter ants deploy several antibiotics to protect fungi they grow as food for their queen and larvae. It is the first time ants have been found using more than one antibiotic in combination. The new antibiotics discovered have anti-fungal effect, and can be useful for modern medicine. UK Medical Research Council funded the investigation.

Leafcutter ant Acromyrmex octospinosus on a stick carrying a leaf Image: Deadstar0.

Acromyrmex octospinosus leaf cutter ants form the biggest known animal colonies, reaching several million individuals. They are native to South and Central America, but are now found in the southern United States as well. They are known to grow fungi gardens, and this is why the researchers looked into the interaction of ants and fungi. The scientists collected them from three colonies in Trinidad and Tobago. UEA professor Dr Matt Hutchings explained, “This was really a fun project which started with a PhD student, Joerg Barke, streaking leaf-cutting ants onto agar plates to isolate antibiotic producing bacteria.”

The health of a certain type of fungus gardens is vital for the ants colony since the fungus is used to feed larvae and the queen. The antibiotics act both as herbicides and regulators of fungus growth. The antibiotics are produced by actinomycete bacteria, which live in a state of symbiosis with the ants, and are found on the bodies of the ants themselves. The symbiotic relationships benefit both the ants and the bacteria.

As a result of the study, a new antibiotic has also been discovered. It’s related to nystatin, one of the antifungals used in modern medicine. The researchers expect to discover more new antibiotics and are optimistic about their use in medicine. Dr Matt Hutchings who was leading the research said, “It’s also very exciting that ants not only evolved agriculture before humans but also combination therapy with natural antibiotics. Humans are just starting to realize that this is one way to slow down the rise of drug resistant bacteria — the so called superbugs.”

Hong Kong tourists held hostage in the Philippines, eight killed

A former Filipino policeman has kept Hong Kong tourists hostage by hijacking their bus in Manila, the capital of the Philippines. Rolando Mendoza fired his M16 rifle at the tourists. Several hostages have been rescued and least six have been confirmed dead so far. Six hostages, including the children and elderly, were released early, as were the Filipino photographers. The photographers later took the place of an aged lady as she needed the lavatory. Mendoza was gunned down.

Mendoza was fired from the Police Force after robbery and drugs claims. His brother explained that ‘his problem was he was unjustly removed from service. There was no due process, no hearing, no complaint.’ Both government officials and his brother had tried to negotiate with him to release the hostages.

Mendoza stuck handwritten notes on the bus. One threatened that a ‘big deal’ would happen after 3pm; another said ‘Big mistake to correct a big wrong decision’. Yet another attempted to catch the attention of the media.

Gunshots were heard inside the bus and Mendoza was shot down. The police rescued the hostages on the bus. The number of survivors totalled seven. Eight were confirmed dead.

The Hong Kong government discussed with Hong Thai Travel and decided to send a plane to take the survivors back to Hong Kong. Ambrose Lee led an ad hoc group to deal with the incident. One police officer and one Immigration Department officer of Hong Kong flew to Manila to help.

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