Category Astronomy/Space

Large-scale crossbedding in the sandstone of this ridge on a lower slope of Mars’ Mount Sharp is typical of windblown sand dunes that have petrified. Image credit: NASA/JPL-Caltech/MSSS

Some of the dark sandstone in an area being explored by NASA’s Curiosity Mars rover shows texture and inclined bedding structures characteristic of deposits that formed as sand dunes, then cemented into rock. This sandstone outcrop, part of a geological layer that Curiosity’s science team calls the Stimson unit, has a structure called crossbedding on a large scale that is interpreted as deposits of sand dunes formed by wind.

Similar-looking petrified sand dunes are common in the U.S. Southwest...

The researchers have discovered 2 craters in Jämtland. One is enormous, while the other is a tenth of the size of the first. “The 2 meteorite impacts occurred at the same time, 458 million years ago, and formed these two craters,” says Prof Erik Sturkell. They found one of the craters 20 kilometres south of Östersund in Brunsflo. This is an enormous crater, with a diameter of 7.5 kilometres. The smaller crater is located 16 kilometres from there, and has a diameter of 700 metres.

“Around 470 million years ago, 2 large asteroids collided in the asteroid belt between Mars and Jupiter, and many fragments were thrown off in new orbits. Many of these crashed on Earth, such as these two in Jämtland,” says Erik Sturkell.

Jämtland was under the sea at the time, with a water depth of 500m at th...

The polarity of the star’s surface magnetic field, north or south, is indicated by red and blue respectively. Yellow lines indicate the magnetic field lines running from the stellar surfaces. Credit: Visualisation courtesy of Volkmar Holzwarth, KIS, Freiburg

The 1st massive binary star, epsilon Lupi, in which both stars have magnetic fields has been discovered by a PhD candidate. A binary star is a star system consisting of 2 or more stars, orbiting around their common center of mass.For the past few years, BinaMIcS (Binarity and Magnetic Interactions in various classes of Stars) collaboration, formed to study the magnetic properties of close binaries, has been trying to find such an object. They have now discovered one using the Canada-France-Hawaii Telescope.

“The origin of magnetism amo...

This image, using data from Spitzer and the Hubble Space Telescope, shows the galaxy cluster SpARCS1049. Credit: NASA/STScI/ESA/JPL-Caltech/McGill

A gargantuan galaxy cluster with a core bursting with new stars has been found: an incredibly rare find. The discovery is the first to show that gigantic galaxies at the centers of massive clusters can grow significantly by feeding off gas stolen from other galaxies.

Galaxy clusters are vast families of galaxies bound together by gravity. Our own galaxy, the Milky Way resides in the small galaxy group called Local Group, which itself is a member of the massive Laniakea supercluster.

Galaxies at the centres of clusters are usually made of stellar fossils — old, red or dead stars...