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Reaction Engines achieves funding goal, plans rocket–jet engine hybrid demo for 2020

14 July 2016

Ars Technica: On Tuesday, UK-based Reaction Engines signed a £10 million contract with the European Space Agency for the development of their Synergistic Air-Breathing Rocket Engine (SABRE). That agreement fulfilled a funding requirement for an additional £50 million from the UK Space Agency. Reaction Engines says that the new funding comes on top of an earlier £20.6 million from BAE Systems and allows the company to develop a ground-based demonstration SABRE engine by 2020. SABRE is a hybrid rocket–jet engine that functions as a jet at low altitudes and as a rocket at high altitudes. The company says the design is possible because of its pre-cooling heat exchanger, which can cool incoming air from 1000 °C to –150 °C in 1 ms (and prevent freezing by injecting methanol into the cooling system). In theory, the engine would be able to power a spaceplane from a horizontal take off all the way to low Earth orbit. This single-stage-to-orbit reusable launch system would be a potentially significant alternative to traditional rockets.

US PhD production is flooding the market for professorships

14 July 2016

New York Times: Tenure-track professorships are one of the most desirable jobs for PhD holders in the sciences. However, in many disciplines people earning PhDs significantly outnumber the available positions. In popular fields like biomedicine, less than one position is available for every six PhD recipients, and across all science and engineering degrees fewer than 50% on average enter academic positions related to their degrees. Many entering academia in non-tenure-track positions end up in low-paying narrowly focused jobs and then leave the field after four to six years. Richard Larson of MIT and his colleagues have calculated replacement rates—how many PhDs professors each trained during their career—for tenure-track positions across several science fields. The highest rate they found was 19.0 PhDs trained per tenure-track professor for environmental engineering; biological and medical sciences were at 6.3. Larson's work suggests that this measurement could be used to help PhD students decide whether to enter academia, industry, or another career field.

Guiding surgical needles

14 July 2016
To track a surgical needle in real time, researchers are using ultrasound and a tiny optical interferometer installed in its tip.

Dale A. Zych

14 July 2016

Dwarf planet discovered in the Kuiper belt

13 July 2016
Science News: The number of dwarf planets orbiting the Sun just increased by one. Called 2015 RR245, it was first observed in February as a slow-moving dot of light beyond Neptune in images captured last September by the Canada-France-Hawaii Telescope. Researchers with the Outer Solar System Origins Survey have determined that it is probably about 700 km in size and travels a highly elliptical orbit—one of the largest orbits of any of the known dwarf planets. Planets that travel so far from the Sun can be interesting to study because of their exotic geology and frozen landscapes and because they can provide details of the early conditions of the solar system. Just five dwarf planets have been officially recognized by the International Astronomical Union, but the actual number of dwarf planets in the solar system may exceed 10 000.

Monetizing your success

13 July 2016
Aid your chances for a raise or promotion by contributing not only to the scholarship of science but also to the bottom line of the enterprise.

Cosmic radiation presents significant obstacle to future Mars mission

12 July 2016
Washington Post: Unlike Earth, which is protected from space radiation by its magnetic field, Mars is constantly bombarded by charged particles and gamma rays. In planning a future mission to Mars with a human crew aboard, NASA has been monitoring those radiation levels with the Curiosity rover, launched in 2011. While it traveled to Mars, Curiosity's radiation assessment detector began gathering readings on radiation levels inside the spacecraft, and it has been monitoring radiation on the planet’s surface since it landed in August 2012. Despite significant differences between predictions of Mars’s radiation levels and actual measurements, scientists remain optimistic that a way will be found to minimize astronauts’ exposure to an acceptable level.

Climate change may be affecting Earth’s cloud cover

12 July 2016
NPR: Since at least the 1980s, clouds in the midlatitudes have been retreating toward the poles, according to a new study in Nature. Two driving forces have been identified: increasing greenhouse gas concentrations and the cooling effect of two volcanic eruptions. Joel Norris of the University of California, San Diego, and colleagues, who based their findings on satellite cloud data gathered over the past several decades, say the changes match those predicted by most climate models of global warming. However, other climate researchers say that because clouds are an extremely complex weather phenomenon, much more data, gathered over much longer time periods, will be needed to completely understand them and their effects on Earth's climate.

Media coverage of Kentucky "Noah's ark" emphasizes science facts

12 July 2016
Creationist Ken Ham's latest public venture promotes adamant opposition to them.

<em>Solar Impulse 2</em> nears end of around-the-world journey

11 July 2016
BBC: After traveling more than a year and making some 15 stops, the solar-powered aircraft Solar Impulse 2 is about to complete its circumnavigation of the globe. The stops allow André Borschberg and Bertrand Piccard, the two men piloting the single-seat craft, to take turns flying. On 11 July Borschberg took off from Seville, Spain, to make the plane’s penultimate flight to Cairo, Egypt. Piccard will fly the final leg, returning Solar Impulse to Abu Dhabi, United Arab Emirates, where it originally took off in March 2015. The trip has taken longer than planned because during the plane’s record-setting flight over the Pacific Ocean from Japan to Hawaii in June 2015, the plane’s batteries overheated and needed to be repaired.

Reversing time with a jolt

11 July 2016
The rapid disruption of propagating water waves spawns swells that run in rewind.

Pokémon Go draws computer gamers outdoors

11 July 2016
New Scientist: Since 6 July an uncommon number of people have been rushing to spend time outdoors. The reason: the release of Pokémon Go, a free augmented-reality game played on mobile devices. Players walk around the real world in order to hunt virtual Pokémon, which are fictional creatures that can be captured, trained to battle, or traded. Even though the game itself is fairly benign, a few problems have already been reported: injuries to players who got so wrapped up in the game that they didn’t pay attention to where they were going and at least one instance of armed robbers targeting a known Pokémon location. But it is unclear whether the game’s designer, Niantic, a former Google subsidiary, has any larger plan for the game, such as using its data to improve location services.

Launch-ready interplanetary CubeSats just need a lift

8 July 2016

Nature: CubeSats, 10-cm-sided spacecraft often built with off-the-shelf parts, are widely used in low Earth orbit (LEO) for a variety of tasks. Although several CubeSats have been designed for interplanetary missions, however, they are still sitting on Earth, waiting for a ride into space. Generally, the spacecraft piggyback on rockets as secondary or even tertiary payloads. Whereas LEO launches are relatively common, launches into higher orbits or out of Earth orbit are far less frequent. Now NASA and the European Space Agency are planning to include CubeSats on several long-range missions, including technology tests and small probes to the Moon, Mars, asteroids, and Jupiter's moon Europa.

LHC has already produced more than twice as much data in 2016 as in 2015

8 July 2016

Ars Technica: From July to November 2015, the Large Hadron Collider (LHC) produced just over 4 inverse femtobarns of data. In its current run, which began in May, the LHC has already produced 10 fb-1. With several more months to go, LHC scientists expect to receive three times as much data this year as last year. The increase in data should help researchers to verify whether the hint of a new particle in last year's data was an actual signal or just noise. The 2016 data haul could also help researchers to statistically rule out a variety of theorized particles and show major flaws in the models that predict them. On a more concrete level, the data should provide significantly more information about already discovered particles that we still don't know much about, such as the Higgs boson.

Bio-inspired swimming robot is powered by light

8 July 2016

New Scientist: A coin-sized robot created from rat tissue has been shown to swim through an obstacle course when exposed to light. The bioengineered stingray, designed by Kevin Kit Parker of Harvard University and coworkers, comprises a tiny gold skeleton covered with a flexible polymer that is layered with about 200 000 rat heart cells. The researchers tweaked the cells to make them light sensitive. By shining different frequencies of light on different sides of the robot, they were able to affect its speed and direction. The ultimate goal, according to Parker, is to better understand how the heart works and one day be able to build one.

Planet found in surprisingly close orbit to three suns

8 July 2016
Los Angeles Times: Thousands of planets have been found to exist in multistar systems. However, what makes the newly discovered triple-star system HD 131399 stand out is the fact that its planet is located so close to its three stars. Because of the complex gravitational forces involved, scientists had assumed that no planet could maintain a stable orbit in such close proximity to so many stars. “This discovery shows us that planets can form or evolve into these almost unstable systems that previously almost seemed like science fiction,” said the University of Arizona's Kevin Wagner, one of the researchers whose paper detailing the discovery appears in Science.

Dark-matter intrigue

7 July 2016
Extra Dimensions: When it comes to the disputed dark-matter detection claim by the DAMA experiment, science is just part of the story.

UK climate advisory committee approves fracking, with conditions

7 July 2016

BBC: The UK's Committee on Climate Change (CCC) has said fracking in the country can go ahead if three conditions are met: Emissions must be strictly limited at all stages of construction, operation, and decommissioning; total UK gas consumption must not increase, which means shale gas must displace imported gas; and shale gas emissions must be included in the UK's already established carbon budgets. The UK government says it already intends to abide by the restrictions, but environmentalists argue that shale gas production will overwhelm the country's attempts to meet its climate change goals. The CCC predicated its decision on a range of projections for gas production, with the most extreme production model predicting 11 million tons of CO2 emissions per year by 2030. That amount is just one-fourth of the country's emissions from agriculture and land-use change. The government will make its final decision on whether to allow fracking—at two sites in Lancashire—by 6 October.

Before failing, Japan's <em>Hitomi</em> satellite returned data on galactic wind

7 July 2016

New Scientist: In March, just over a month after it launched, the Japan Aerospace Exploration Agency's Hitomi x-ray telescope suffered a failure that rendered it inoperable. Now the satellite team has released a paper showing that Hitomi was able to collect useful information before it died. Andrew Fabian of the University of Cambridge and his colleagues used Hitomi data to map the flow of plasma away from the Perseus cluster of galaxies and out into intergalactic space. Hitomi's images reveal that the flow is massive, with gusts of plasma larger than the Milky Way. The galactic wind is driven by a supermassive black hole located at the center of the cluster's central galaxy. The black hole creates jets of particles that travel near the speed of light and blow cooler gas out of the cluster.

New satellite to monitor Earth’s carbon emissions

7 July 2016
IEEE Spectrum: On 22 June the Claire satellite was successfully launched by Montreal-based developer GHGSat. It is the first of a planned fleet of such satellites dedicated to the remote sensing of greenhouse gas emissions from industrial sites. Claire, which is equipped with an IR spectrometer and telescopic lensing, will fly around the world taking a series of high-resolution aerial snapshots of thousands of sites. The data it gathers will be used to improve emissions reporting, track industrial efficiency, and provide competitive intelligence, says GHGSat president Stéphane Germain.

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