Picture This

A supermassive black hole in action

Scientists often use the combined power of multiple telescopes to reveal the secrets of the universe — and this image of elliptical galaxy Hercules A is a prime example of when this technique is strikingly effective. Radio observations with the Karl G. Jansky Very Large Array were combined with the Hubble visible-light data obtained with the Wide Field Camera 3 to create this striking composite image.

News

Dark matter dominates in nearby dwarf galaxy

Dark matter is called “dark” for a good reason. Although they outnumber particles of regular matter by more than a factor of 10, particles of dark matter are elusive. Now, by measuring the mass of a nearby dwarf galaxy called Triangulum II, astronomers believe they may have found the highest concentration of dark matter in any known galaxy.

Picture This

A brighter Saturnian moon

Although Saturn’s moons Dione (near) and Enceladus (far) are composed of nearly the same materials, Enceladus has a considerably higher reflectivity than Dione. As a result, it appears brighter against the dark night sky. This image was taken by NASA’s Cassini spacecraft in visible light with the narrow-angle camera on 8 September 2015.

News

Visualising the Sun’s neighbourhood in 3-D

Astronomers have used modern techniques to create a 3-D visualisation of all of the O- and B-type stars within 500 parsecs (1,630 light-years) of the Sun using data from ESA’s Hipparcos satellite. This new visualisation uncovers evidence for new structures in the distribution of these nearby hot stars, and new and surprising theories of how those stars formed.

News

Discovery measures “heartbeats” of a distant galaxy’s stars

In many ways stars are like living beings. They’re born; they live; they die. And they even have a heartbeat. Near the end of their lifetime they begin to pulsate, increasing and decreasing their brightness by a large amount every few hundred days. Using a novel technique, astronomers have detected thousands of stellar “pulses” in the galaxy Messier 87 (M87). Their measurements offer a new way of determining a galaxy’s age.