Category Astronomy/Space

Artistic representation of coherent control of femtosecond nanomagnons. Credit: Image courtesy of Radboud University

Scientists have achieved the ultimate speed limit of the control of spins in a solid state magnetic material. The rise of the digital information era posed a daunting challenge to develop ever faster and smaller devices for data storage and processing. An approach which relies on the magnetic moment of electrons (i.e. the spin) rather than the charge, has recently turned into major research fields, called spintronics and magnonics.

The researchers were able to induce spin oscillations of the intrinsically highest frequency by using femtosecond laser pulses (1 fs = 10-15 sec)...

Ion thrusters are being designed for a wide variety of missions – from keeping communications satellites in the proper position to propelling spacecraft throughout our solar system. But, what exactly is ion propulsion and how does an ion thruster work?

~Regular Rocket Engines: You heat it up a gas, or put it under pressure, and you push it out of the rocket nozzle, and the action of the gas going out of the nozzle causes a reaction that pushes the spacecraft in the other direction.
~Ion Engines: Xenon gas gets a little electric charge, then they’re called ions, and we use a big voltage to accelerate the xenon ions through this metal grid and we shoot them out of the engine at up to 90,000 miles per hour.

Something interesting about ion engines is that it pushes on the spacecraft as h...

Researchers have calculated the dust chemistry of the solar nebula (thin dusty ring around young sun) Image credit: NASA/FUSE/Lynette Cook

Using sophisticated computer simulations, team has discovered new insights into the chemical composition of the dust grains that formed in the solar system 4.5 billion years ago. Researchers from Swinburne Uni of Technology, Melbourne and the Uni of Lyon, France, calculated a 2D map of the dust chemistry in the solar nebula, the thin dusty disk that surrounded the young sun and out of which the planet formed.

It is expected that refractories (high temperature materials) should be located close to the young sun, while volatile materials (such as ices and sulphur compounds) should form far from the sun where temperatures are cooler...

This is a Simulation of a gravitationally unstable circumstellar disk by means of hydrodynamic calculations. Protoplanetary ’embryo’ form in the disc thanks to gravitational fragmentation. The three small pictures show the successive ‘disappearance’ of the lump by the star. Credit: Copyright Eduard Vorobyov, Universität Wien

New research shows the turbulent past of our sun. Stars are born inside a rotating cloud of interstellar gas and dust, which contracts to stellar densities thanks to its own gravity. Before finding itself on the star, however, most of the cloud lands onto a circumstellar disk forming around the star owing to conservation of angular momentum...