Physics Today Daily Edition
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.
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.
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.
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.
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.
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.
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.