Researchers created an optomechanical silicon bullseye disk that traps optical waves in the outermost ring via total internal reflection while the radial groves confine the mechanical waves to the same area. Credit: Thiago P. Mayer Alegre, University of Campinas

Trapping light and mechanical waves within a tiny bullseye, design could enable more sensitive motion detection. The new device is highly customizable and compatible with commercial manufacturing processes. Optomechanical devices use light to detect movement. They can be used as low-power, efficient building blocks for the accelerometers that detect the orientation and movement of a smart phone or that trigger a car’s airbag to deploy split seconds after an accident...

On canvas, the consistency of gels and gel-paint mixtures differs greatly from that of paint alone, which spreads without retaining volume. Credit: © Hélène Pasco, LAMS (CNRS, UPMC)

To paint quickly while creating exceptional texture and volume effects, J. M. W. Turner and other English artists of his generation relied on the development of innovative gels. All the rage in the 19th century – and still in use today – these compounds alter the properties of the oil paints they are combined with. CNRS, UPMC, and Collège de France researchers have finally learned the chemical secrets behind these mixtures. Lead – in its acetate form – is essential for the formation of the gels.

Oil paints were traditionally made by grinding pigments together with linseed, walnut, or poppy oil...

Molnar’s prediction is that a binary star (two stars orbiting each other) he is monitoring will merge and explode in 2022. Credit: Calvin College

Calvin College professor Larry Molnar et al are predicting a change to the night sky that will be visible to the naked eye. “It’s a 1-in-a-million chance that you can predict an explosion,” Molnar said. “It’s never been done before.” Molnar’s prediction is that a binary star he is monitoring will merge and explode in 2022, give or take a year; at which time the star will increase its brightness 10000X, becoming one of the brighter stars in the heavens for a time. The star will be visible as part of the constellation Cygnus, and will add a star to the recognizable Northern Cross star pattern.

Molnar’s exploration into the star known as KIC 98322...

A multi-wavelength image of the field around Sagitarrius A*, the supermassive black hole at the center of the Milky Way galaxy (SgrA* is an imperceptible speck located at the center of this large field of sky). Astronomers have used an array of millimeter-wave telescope facilities to detect a small asymmetry that might be associated with the shadow of the black hole. Credit: NASA

The supermassive black hole candidate at the center of our Galaxy (associated with the radio source Sgr A*) is a prime candidate for studying the physical phenomena associated with accretion on to a supermassive black hole...