News

Detonating white dwarfs as supernovae

A new mathematical model created by astrophysicists at the American Museum of Natural History details a way that dead stars called white dwarfs could detonate, producing a type of explosion that is instrumental to measuring the extreme distances in our universe. The mechanism could improve our understanding of how Type Ia supernovae form.

News

Saturn’s moon Dione harbours a subsurface ocean

A subsurface ocean lies deep within Saturn’s moon Dione, according to new data from the Cassini mission. Two other moons of Saturn, Titan and Enceladus, are already known to hide global oceans beneath their icy crusts. Researchers believe that Dione’s crust floats on an ocean several tens of kilometres deep located 100 kilometres below the surface.

News

Millisecond pulsars in globular cluster 47 Tucanae

Pulsars are rapidly spinning neutron stars that emit electromagnetic radiation in a sweeping, lighthouse-like beam. They are dramatic, powerful probes of supernovae, their progenitor stars. Astronomers have measured the orbital parameters of four millisecond pulsars in the globular cluster 47 Tucanae and modelled their possible formation and evolution paths.

Picture This

Hubble probes the core of galaxy NGC 247

NGC 247 is a relatively small spiral galaxy in the southern constellation of Cetus (The Whale), part of the Sculptor Group around 11 million light-years from us. NGC 247 displays one particularly unusual and mysterious feature — an apparent void in the usual swarm of stars and H II regions in the northern part of its disc that spans almost a third of the galaxy’s total length.

News

Protoplanetary disc’s spiral arms embrace young star

Swirling around the young star Elias 2-27 is a stunning spiral-shape pinwheel of dust. This striking feature, seen with the Atacama Large Millimetre/submillimetre Array (ALMA), is the product of density waves — gravitational perturbations in the star’s protoplanetary disc that produce sweeping arms reminiscent of a spiral galaxy, but on a much smaller scale.