Category Astronomy/Space

Artist’s impression of an inner accretion flow and a jet from a supermassive black hole when it is actively feeding, for example, from a star that it recent tore apart. Image: ESO/L. Calçada

Signals suggest black hole emits a jet of energy proportional to the stellar material it gobbles up. On Nov. 11, 2014, a global network of telescopes picked up signals from 300 million light years away that were created by a tidal disruption flare – an explosion of electromagnetic energy that occurs when a black hole rips apart a passing star. Since this discovery, astronomers have trained other telescopes on this very rare event to learn more about how black holes devour matter and regulate the growth of galaxies.

Scientists from MIT and Johns Hopkins University have now detected radio signals from t...

Artist’s conception of Scholz’s star and its brown dwarf companion (foreground) during its flyby of the solar system 70,000 years ago. The Sun (left, background) would have appeared as a brilliant star. The pair is now about 20 light years away. / Michael Osadciw/University of Rochester

New evidence of the passage of Scholz’s star. About 70,000 years ago, a small reddish star approached our solar system and gravitationally disturbed comets and asteroids. Astronomers from the Complutense University of Madrid and the University of Cambridge have verified that the movement of some of these objects is still marked by that stellar encounter.

At a time when modern humans were beginning to leave Africa and the Neanderthals were living on our planet, Scholz’s star – named after the German astronom...

Using data from three different satellites, scientists have developed new models that recreate, in 3-D, CMEs and shocks, separately. Credit: Image courtesy of NASA/Goddard Space Flight Center

Scientists have developed new models to see how shocks associated with coronal mass ejections, or CMEs, propagate from the Sun – an effort made possible only by combining data from 3 NASA satellites to produce a much more robust mapping of a CME than any one could do alone. CMEs set off interplanetary shocks when they erupt from the Sun at extreme speeds, propelling a wave of high-energy particles. These particles can spark space weather events around Earth, endangering spacecraft and astronauts.

Understanding a shock’s structure – particularly how it develops and accelerates – is key to predicting ho...

All seven planets discovered in orbit around the red dwarf star TRAPPIST-1 could easily fit inside the orbit of Mercury, the innermost planet of our solar system. Credit: NASA/JPL- Caltech

To determine the composition of the TRAPPIST-1 planets, the team used a unique software package that uses state-of-the-art mineral physics calculators. The software, called ExoPlex, allowed the team to combine all of the available information about the TRAPPIST-1 system, including the chemical makeup of the star, rather than being limited to just the mass and radius of individual planets.

TRAPPIST-1 is an ultra-cool red dwarf star that is slightly larger, but much more massive, than the planet Jupiter, located about 40 light-years from the Sun in the constellation Aquarius...