Astronomy Now Home
Home Magazine Resources Store

On Sale Now!

The October 2014 issue of Astronomy Now is on sale! Order direct from our store (free 1st class post & to UK addresses). Astronomy Now is the only astronomy magazine specially designed to be read on tablets and phones. Download the app from Google Play Store or the Apple App Store.

Top Stories

Earthshine used to test life detection method
...By imagining the Earth as an exoplanet, scientists observing our planet's reflected light on the Moon with ESO's Very Large Telescope have demonstrated a way to detect life on other worlds...

Solid buckyballs discovered in space
...Astronomers using NASA’s Spitzer Space Telescope have detected a particular type of molecule, given the nickname “buckyball”, in a solid form for the first time...

Steamy water-world gets the Hubble treatment
...Hubble Space Telescope observations of a 7 Earth-mass planet find an unusual water-rich world swathed in a thick, steamy atmosphere...

First direct imaging of a young binary system
Posted: December 17, 2009

Bookmark and Share

A team of astronomers have captured the first direct image of a young binary star system using the Coronographic Imager with Adaptive Optics on the Subaru Telescope.

Observed and simulated images of the young binary star SR24 (distance: 520 light years). Image: The graduate University for Advanced Studies & the National Astronomical Observatory of Japan/Chiba University.

The binary star system, SR24, resides 520 light years away in the constellation Ophiuchus. The study, conducted in July 2006, provides important information about how binary stars are born and evolve. In binary systems, two stars orbit around a common centre of mass; the brighter star or massive star is referred to as the primary star and the fainter or less massive star the secondary star. Both star host a disc of material and a third disc may envelope both stars and supply the stars' discs with mass via a connecting spiral arm.

Despite most stars forming in binary or multiple systems, their discs and spiral arms have rarely been directly imaged, that is, until now. The team, lead by astronomers at the National Astronomical Observatory of Japan, captured a high resolution near-infrared image of the discs around each star – the first such image of twin protoplanetary discs around a young stellar object. The images also revealed a long spiral arm extending out from the disc, and a bridge of gas connecting the two discs.

Three-dimensional numerical simulation image of young binary star system. Image: Hosei University.

By inputing various aspects of the observations into supercomputer simulations of accretion and disc formation, the team were able to generate structures similar to those seen in the image. The results suggest that fresh material streams along the spiral arm, replenishing the primary star's disc with a reservoir of gas contained in the disc surrounding both stars. The simulations also suggest that the bridge connecting the stars' discs corresponds to gas flow and a shock wave caused by the collision of gas rotating around the primary and secondary stars.

The findings provide a better understanding of the process of star and planet formation in a binary system by clarifying the role of supporting structures in maintaining the binary system.

The Planets
From tiny Mercury to distant Neptune and Pluto, The Planets profiles each of the Solar System's members in depth, featuring the latest imagery from space missions. The tallest mountains, the deepest canyons, the strongest winds, raging atmospheric storms, terrain studded with craters and vast worlds of ice are just some of the sights you'll see on this 100-page tour of the planets.

Hubble Reborn
Hubble Reborn takes the reader on a journey through the Universe with spectacular full-colour pictures of galaxies, nebulae, planets and stars as seen through Hubble's eyes, along the way telling the dramatic story of the space telescope, including interviews with key scientists and astronauts.

3D Universe
Witness the most awesome sights of the Universe as they were meant to be seen in this 100-page extravaganza of planets, galaxies and star-scapes, all in 3D!


© 2014 Pole Star Publications Ltd.