Giant radio galaxies (GRGs) are one of the largest astrophysical sources in the Universe with an overall projected linear size of ∼0.7 Mpc or more. The last six decades of radio astronomy research has led to the detection of thousands of radio galaxies. However, only ∼300 of them can be classified as GRGs. The reasons behind their large size and rarity are unknown. We carried out a systematic search for these radio giants and found a large sample of GRGs.

Seven small planets whose surfaces could harbour liquid water have been spotted around a nearby dwarf star. If such a configuration is common in planetary systems, our Galaxy could be teeming with Earth-like planets.

Physicists think they may have discovered a fifth force of nature, and if this is true, then it would totally redefine how people understand how the universe.

Solar magnetism displays a host of variational timescales of which the enigmatic 11-year sunspot cycle is most prominent. Recent work has demonstrated that the sunspot cycle can be explained in terms of the intra- and extra-hemispheric interaction between the overlapping activity bands of the 22-year magnetic polarity cycle. Those activity bands appear to be driven by the rotation of the Sun’s deep interior. Here we deduce that activity band interaction can qualitatively explain the ‘Gnevyshev Gap’—a well-established feature of flare and sunspot occurrence.

Convective motion in the deep metallic hydrogen region of Jupiter is believed to generate its magnetic field, the strongest in the solar system. The amplitude, structure and depth of the convective motion are unknown. A promising way of probing the Jovian convective dynamo is to measure its effect on the external gravitational field, a task to be soon undertaken by the Juno spacecraft.

Based on two detectors separated by about 3,000 km and using ultra-stable lasers, a new observatory known as the Advanced LIGO has detected gravitational waves generated by the coalescence of two black holes, that turned into a new black hole with the release of about five solar masses of energy in a few milliseconds at a distance of over a billion light years, thus confirming one of the last untested predictions of the General Theory of Relativity.

On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0 × 10−21. It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole.

LIGO 'hears' space-time ripples produced by black-hole collision.

On 25 September, a sensational rumour appeared on Twitter: Lawrence Krauss, a cosmologist, reported hearing that the world’s largest gravitational-wave observatory had seen a signal, barely a week after its official re-opening.

Aurorae are detected from all the magnetized planets in our Solar System, including Earth. They are powered by magnetospheric current systems that lead to the precipitation of energetic electrons into the high-latitude regions of the upper atmosphere.