Category Astronomy/Space

White dwarf (right) stripping mass from the brown dwarf. Credit: Rene Breton, University of Manchester.

Astronomers have detected a sub-stellar object that used to be a star, after being consumed by its white dwarf companion. An international team of astronomers made the discovery by observing a very faint binary system, J1433 730 light-years away. The system consists of a low-mass object – 60X the mass of Jupiter – in an extremely tight 78-min orbit around a white dwarf (the remnant of a star like our Sun).

Due to their close proximity, the white dwarf strips mass from its low-mass companion. This process has removed about 90% of the mass of the companion, turning it from a star into a brown dwarf...

A thrust fault rips to the surface of a numerical Io. As it breaches the surface, it pulls on the overhanging crustal block (to the left of the fault), and ‘extensional’ features such as trenches called graben form there. The fault also provides a conduit for rising magma and collapsing magma chambers form ‘patera’, or depressions on the surface. The stair-stepping is an artifact; the simulation divides the crust into small elements so that simpler (solvable) functions can be used to describe the rock mechanics. Credit: Bland and McKinnon

Novel mountain-building mechanism on Io may also have operated on early Earth By Diana Lutz May 17, 2016. Mountains aren’t the first thing that hit you when you look at images of Jupiter’s innermost moon, Io...

On present-day Europa, the researchers expect water could reach as deep as 25 kilometers (15 miles) into the rocky interior, driving key chemical reactions throughout a deeper fraction of Europa’s seafloor. Credit: NASA/JPL/University of Arizona

The ocean of Jupiter’s moon Europa could have the necessary balance of chemical energy for life, even if the moon lacks volcanic hydrothermal activity, finds a new study. Europa is strongly believed to hide a deep ocean of salty liquid water beneath its icy shell. The answer may hinge on whether Europa has environments where chemicals are matched in the right proportions to power biological processes. Life on Earth exploits such niches.

JPL scientists compared Europa’s potential for producing hydrogen and oxygen with that of Earth, through processe...

False-colour image of the stellar open cluster M67. Red, green, blue composite based on Johnson B, V and G bandpass images. Captured with WiFSIP/STELLA on Tenerife. Credit: AIP

It turns out these stars spin around once in ~26 days – just like our Sun. This discovery significantly strengthens what is known as the solar-stellar connection, a fundamental principle that guides much of modern solar and stellar astrophysics. This principle – that the Sun is a star – was only proved in the 19th century when distances to the nearest stars were measured. It enables us to use the Sun, the only star we can observe in detail, to study processes occurring on other stars, and conversely, to use other stars to infer the past and future of our Sun...