Category Astronomy/Space

Sequence showing two white dwarfs spiraling into one another, merging and then exploding as a supernova. As they spiral around each other, they emit gravitational waves causing them to grow ever closer. Credit: GSFC/Dana Berry.

A team of international astrophysicists led by ANU has shown how most of the antimatter in the Milky Way forms. Antimatter is material composed of the antiparticle partners of ordinary matter – when antimatter meets with matter, they quickly annihilate each other to form a burst of energy in the form of gamma-rays. Scientists have known since the early 1970s that the inner parts of the Milky Way galaxy are a strong source of gamma-rays, indicating the existence of antimatter, but there had been no settled view on where the antimatter came from.

ANU researcher Dr R...

This is the ASKAP telescope in Western Australia. Credit: CSIRO

A CSIRO telescope in W. Australia has found its first ‘fast radio burst’ from space after less than 4 days of searching. The discovery came so quickly that the telescope, the Australian Square Kilometre Array Pathfinder (ASKAP) near Geraldton in Western Australia, looks set to become a world champion in this fiercely competitive area of astronomy. The new fast radio burst finding was published in the Astrophysical Journal Letters.

‘Fast radio bursts’ or FRBs are short, sharp spikes of radio waves lasting a few milliseconds. They appear to come from powerful events billions of light-years away but their cause is still a mystery. The first was discovered in 2007 and only 2 dozen have been found since...

1.Evolution of the magnetic field in two simulations of the formation of active solar regions. Top row: non-eruptive scenario where the configuration remains stable. Bottom row: eruptive scenario.
Credit: © E.Pariat, figure adapted from Pariat & al, A&A 2017
2. Time evolution of the value of a quantity based on magnetic helicity, for the various numerical simulations tested. This predictive quantity has high values before the eruption in the eruptive simulations (red, orange and yellow curves) and low values in the non-eruptive cases (black, violet, blue and cyan curves).
3. Artist’s impression of a solar flare and the twisted magnetic field that carries away the ejected solar material.

The emerging discipline of space meteorology aims to reliably predict solar flares so that we may better g...

Light curve of the microlensing event OGLE-2016-BLG-1469. The upper panel shows the enlarged view of the anomaly around the peak. The two lower panels show the residual from the binary-lens models with (orbit+parallax) and without (standard) considering higher-order effects. Credit: Han et al., 2017.

Using gravitational microlensing, astronomers have recently found a binary star composed of two brown dwarfs. The newly discovered system is the third brown-dwarf binary detected with this technique. Gravitational microlensing is an invaluable method of detecting new extrasolar planets and brown dwarfs, regardless of the light they emit...