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When scientists send their spacecraft across the universe, they save fuel by performing “slingshot fly-bys”. This is where, rather than firing up the thrusters, the craft changes its trajectory by harnessing the enormous gravitational pull of a planet. However, this trick has had an unexpected side-effect: it seems to produce a change in speed that no one, since it was first discovered in the early 1990's, can account for. Experts are intrigued by the fact that while the acceleration is tiny and has no significant effect on NASA missions, it holds great interest because no explanation based on conventional physics...

Data from a spacecraft orbiting Earth has revealed ripple structures in the termination shock and heliopause: shifting regions of space that mark one of the boundaries between the space inside the Solar System, and...interstellar space. ...Sun affects the space around it...solar wind, a constant supersonic flow of ionized plasma. It blows out past the planets and the Kuiper Belt, eventually petering out in the great emptiness between the stars. The point at which this flow falls below the speed at which sound waves can travel through the diffuse interstallar medium is called the termination shock, and the point at which...

A FORMER NASA scientist has claimed time travel is possible because the “speed of light is changing”. ============================================================== Louise Riofrio is involved in a project that will put an atomic clock into the International Space Station to “verify” her theory. She reached the conclusion that the speed of light is changing while working at NASA. The scientist analysed lasers that bounced off reflectors left by astronauts on the moon, which appeared to show the moon was moving too fast. But – when she compared it to various experiments on Earth using fossils, observations of ancient eclipses and computer simulations –...

GPS has a new job. It does a great job of telling us our location, but the network of hyper-accurate clocks in space could get a fix on something far more elusive: dark matter. Dark matter makes up 80 per cent of the universe's matter but scarcely interacts with ordinary matter. A novel particle is the most popular candidate, but Andrei Derevianko at the University of Nevada, Reno, and Maxim Pospelov at the Perimeter Institute in Waterloo, Ontario, Canada propose that kinks or cracks in the quantum fields that permeate the universe could be the culprit. If they are right,...

Europe's innovative Goce satellite has switched on the super-sensitive instrument that will make ultra-fine measurements of Earth's gravity. The sophisticated gradiometer will feel the subtle variations in Earth's tug as it sweeps around the globe. The spacecraft has also fired up the British-built engine that will help maintain its orbit. Goce needs tiny but continuous levels of thrust to keep it stable and prevent it from falling out of the sky. European Space Agency (Esa) mission manager Rune Floberghagen said all systems on the spacecraft had now been activated following the launch from Russia last month.

Nearly three years ago, NASA's oft-canceled $750 million Gravity Probe B Relativity Mission finally shot into space with one goal -- to quantify Einstein's predictions from Earth's orbit. Earlier this year, at the meeting of the American Physics Society, principal investigator Francis Everitt delivered the first results: Gravity Probe B has verified Einstein's theory to within 1 percent... Einstein's theory predicts that the axes should shift by a tiny amount -- 0.0018 degree -- under the influence of Earth's pull on space-time. After 18 months of data analysis, Everitt and his team measured the axial shift to within 1 percent...

Going Beyond Einstein: Spacetime Wave Orbits Black Hole San Diego, CA--Astronomers Jon Miller (Harvard-Smithsonian Center for Astrophysics) and Jeroen Homan (MIT) have seen evidence of hot iron gas riding a ripple in spacetime around a black hole. This spacetime wave, if confirmed, would represent a new phenomenon that goes beyond Einstein's general relativity. These observations confirm one important theory about how a black hole's extreme gravity can stretch light. The data also paint an intriguing image of how a spinning black hole can drag the very fabric of space around with it, creating a choppy spacetime sea that distorts everything...

Earth's spin warps space around the planet, according to a new study that confirms a key prediction of Einstein's general theory of relativity. After 11 years of watching the movements of two Earth-orbiting satellites, researchers found each is dragged by about 6 feet (2 meters) every year because the very fabric of space is twisted by our whirling world. The results, announced today, are much more precise than preliminary findings published by the same group in the late 1990s. Frame dragging The effect is called frame dragging. It is a modification to the simpler aspects of gravity set out by...