Category Astronomy/Space

A false-color image map of the gas density in the Musca star-forming filament (the highest densities are shown in red). New theoretical work on the structure of these long filaments proposes several kinds of star-forming zones along the length and successfully reproduces many of the features seen in filaments like this one in Musca. Kainulainen, 2016

Interstellar molecular clouds are often seen to be elongated and “filamentary” in shape, and come in a wide range of sizes. In molecular clouds, where stars form, the filamentary structure is thought to play an important role in star formation as the matter collapses to form protostars...

Artists’ impression of the gas and dust disk around the planet-like object OTS44. First radio observations indicate that OTS44 has formed in the same way as a young star. Credit: Johan Olofsson (U Valparaiso & MPIA)

First radio observations of the lonely, planet-like object OTS44 reveal a dusty protoplanetary disk that is very similar to disks around young stars. This is unexpected, given that models of star and planet formation predict that formation from a collapsing cloud, forming a central object with surrounding disk, should not be possible for such low-mass objects. Apparently, stars and planet-like objects are more similar than previously thought...

Oblique view of the reconnection region. Magnetic field direction is represented by the cyan lines. The color trail represents an electron moving in the field. Color of the particle trail represents a dimensionless speed of the particle, with blue for slow and red for fast. Credit: NASA’s Goddard Space Flight Center/Tom Bridgman

You can’t see them, but swarms of electrons are buzzing through the magnetosphere around Earth. The electrons spiral and dive around the planet in a complex dance dictated by the magnetic and electric fields. When they penetrate into the magnetosphere close enough to Earth, the high-energy electrons can damage satellites in orbit and trigger auroras...

Left to right: River networks on Mars, Earth, and Titan. Researchers report that Titan, like Mars but unlike Earth, has not undergone any active plate tectonics in its recent past. Credit: Benjamin Black/NASA/Visible Earth/JPL/Cassini RADAR team. Adapted from images from NASA Viking, NASA/Visible Earth, and NASA/JPL/Cassini RADAR team

Rivers on 3 worlds tell different tales. The environment on Titan, Saturn’s largest moon, may seem surprisingly familiar: Clouds condense and rain down on the surface, feeding rivers that flow into oceans and lakes. Outside of Earth, Titan is the only other planetary body in the solar system with actively flowing rivers, though they’re fed by liquid methane instead of water. Long ago, Mars also hosted rivers, which scoured valleys across its now-arid surface...