Category Astronomy/Space

The RGB (Red Green Blue image) of the cluster. Red color shows optical radiation, Green shows Radio and Blue color shows X-rays emission. Credit: Chandra X-Ray Observatory

The discovery by a physics doctoral student at The University of Alabama in Huntsville (UAH) of the 2nd-strongest merger shock in clusters of galaxies ever observed has generated excitement that is opening doors to further scientific exploration. Sarthak Dasadia discovered the very strong shock in the merging galaxy cluster Abell 655 using observations from the Chandra X-ray Observatory. The shock to the north of this cluster is second in strength only to the Bullet Cluster shock.

The shock is traveling with an astonishing speed of 2,700km/s, 3X the local speed of sound in the cluster...

This is an artist’s conception of Planet Nine. Credit: Caltech/R. Hurt (IPAC)

Earlier this year scientists presented evidence for Planet Nine, a Neptune-mass planet in an elliptical orbit 10 times farther from our Sun than Pluto. Since then theorists have puzzled over how this planet could end up in such a distant orbit. New research by astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) examines a number of scenarios and finds that most of them have low probabilities. Therefore, the presence of Planet Nine remains a bit of a mystery.

“The evidence points to Planet Nine existing, but we can’t explain for certain how it was produced,” says CfA astronomer Gongjie Li...

Figure 6 from Nikitczuk et al. Credit: GSA Bulletin and Nikitczuk et al.

Tubular microtunnels believed to be the trace fossils formed by microbes inhabiting volcanic rock interiors have only been reported in oceanic and subglacial settings. This is the first observation of such features in basaltic volcanic glass erupted in a continental lake environment, the Fort Rock volcanic field. As a result, the record of subsurface microbial activity in the form of endolithic microborings is prospectively expanded. Our understanding of the range of environments and conditions that microtunnels can form in is enhanced along with our knowledge of potentially habitable environments on Earth and beyond.

The Fort Rock volcanic field has analogous characteristics to locations found on Mars such as Gale an...

Comparison of morphologies formed by the flow of liquid water on Earth and on Mars. Credit: Marion Massé

At present, liquid water on Mars only exists in small quantities as a boiling liquid, and only during the warmest time of day in summer. Its role has therefore been considered insignificant until now. However, an international team including scientists has now shown that even though water that emerges onto the surface of Mars immediately begins to boil, it creates an unstable, turbulent flow that can eject sediment and cause dry avalanches. The flow of small amounts of a boiling liquid therefore significantly alters the surface...