Heavens

Scientists have discovered a solar system with 5 Earth-sized planets dating back to the dawn of the Galaxy.

Thanks to the NASA Kepler mission, the scientists announced today (Tuesday 27 January 2015) in The Astrophysical Journal the observation of a Sun-like star (Kepler-444) hosting 5 planets with sizes between Mercury and Venus.

Kepler-444 was formed 11.2 billion years ago, when the Universe was less than 20% its current age. This is the oldest known system of terrestrial-sized planets in our Galaxy - 2 and a half times older than the Earth.

Astronomers poring over four years of data from NASA's Kepler spacecraft have discovered a star that's 11.2 billion years old and has at least five Earth-size planets.

Astronomers at the Leiden Observatory, The Netherlands, and the University of Rochester, USA, have discovered that the ring system that they see eclipse the very young Sun-like star J1407 is of enormous proportions, much larger and heavier than the ring system of Saturn. The ring system - the first of its kind to be found outside our solar system - was discovered in 2012 by a team led by Rochester's Eric Mamajek.

A multinational team of astronomers working on the High Energy Stereoscopic System (H.E.S.S.) telescopes found three extremely luminous gamma-ray sources in the Large Magellanic Cloud (LMC), a satellite dwarf galaxy of the Milky Way. These are objects of different types, namely the most powerful pulsar wind nebula; the most powerful supernova remnant; and a shell of 270 light years in diameter blown by multiple stars, and supernovae - a so-called superbubble.

The dying moments of an asteroid's magnetic field have been successfully captured by researchers, in a study that offers a tantalising glimpse of what may happen to the Earth's magnetic core billions of years from now.

Thinking small has enabled an international team of scientists to gain new insight into the evolution of planetary building blocks in the early solar system.

The researchers compared the results of small-scale numerical simulations of colliding rock and dust particles to the composition of meteorites. They found that collisions helped transform initially porous materials into the more highly solidified asteroids and meteorites observed today. The team of seven scientists published their evidence last month in Nature Communications.

Fast radio bursts are quick, bright flashes of radio waves from an unknown source in space. They are a mysterious phenomenon that last only a few milliseconds, and until now they have not been observed in real time. An international team of astronomers, including three from the Carnegie Observatories, has for the first time observed a fast radio burst happening live. Their work is published in Monthly Notices of the Royal Astronomical Society.

NASA's Kepler Space Telescope, despite being hobbled by the loss of critical guidance systems, has discovered a star with three planets only slightly larger than Earth. The outermost planet orbits in the "Goldilocks" zone, a region where surface temperatures could be moderate enough for liquid water and perhaps life, to exist.

A study by astrophysicists at the University of Toronto suggests that exoplanets - planets outside our solar system - are more likely to have liquid water and be more habitable than we thought.

"Planets with potential oceans could have a climate that is much more similar to Earth's than previously expected," said Jérémy Leconte, a postdoctoral fellow at the Canadian Institute for Theoretical Astrophysics (CITA) at the University of Toronto, and lead author of a study published today in Science Express.

esearchers at Kavli IPMU and their collaborators have revealed that considering environmental effects such as a gravitational tidal force spread over a scale much larger than a galaxy cluster is indispensable to explain the distribution and evolution of dark matter halos around galaxies. A detailed comparison between theory and simulations made this work possible. The results of this study, which are published in Physical Review D as an Editors' Suggestion, contribute to a better understanding of fundamental physics of the universe.

If you sweep a laser pointer across the Moon fast enough, you can create spots that actually move faster than light, a theoretical curiosity that could practically useful out in the cosmos.

In an interstellar race against time, astronomers have measured the space-time warp in the gravity of a binary star and determined the mass of a neutron star--just before it vanished from view.

The international team, including University of British Columbia astronomer Ingrid Stairs, measured the masses of both stars in binary pulsar system J1906. The pulsar spins and emits a lighthouse-like beam of radio waves every 144 milliseconds. It orbits its companion star in a little under four hours.

Some of the stars appear to be missing in this intriguing new ESO image. But the black gap in this glitteringly beautiful starfield is not really a gap, but rather a region of space clogged with gas and dust. This dark cloud is called LDN 483 -- for Lynds Dark Nebula 483. Such clouds are the birthplaces of future stars. The Wide Field Imager, an instrument mounted on the MPG/ESO 2.2-metre telescope at ESO's La Silla Observatory in Chile, captured this image of LDN 483 and its surroundings.

Astronomers announced today that they have found eight new planets in the "Goldilocks" zone of their stars, orbiting at a distance where liquid water can exist on the planet's surface. This doubles the number of small planets (less than twice the diameter of Earth) believed to be in the habitable zone of their parent stars. Among these eight, the team identified two that are the most similar to Earth of any known exoplanets to date.

A recently study presents a method by which the age of stars can be determined very precisely: "Gyrochronology", an analytical procedure for determining the ages of stars with knowledge of their masses and rotation periods. The word "Gyrochronology" is a neologism of the AIP scientist and co-author of the study, Sydney Barnes.