Hubble Finds Infant Stars In Neighbouring Galaxy

COSMOLOGY

Hubble Finds Infant Stars In Neighbouring Galaxy

The exquisite sharpness of the NASA/ESA Hubble Space Telescope has plucked out an underlying population of infant stars embedded in the nebula NGC 346 that are still forming from gravitationally collapsing gas clouds. They have not yet ignited their hydrogen fuel to sustain nuclear fusion. The smallest of these infant stars is only half the mass of our Sun. Credit: NASA, ESA and A. Nota (STScI/ESA).

Baltimore MD (SPX) Jan 13, 2005
Hubble astronomers have uncovered, for the first time, a population of infant stars in the Milky Way satellite galaxy, the Small Magellanic Cloud (SMC, visible to the naked eye in the southern constellation Tucana), located 210,000 light-years away.

They have not yet ignited their hydrogen fuel to sustain nuclear fusion. The smallest of these infant stars is only half the mass of our Sun.

Although star birth is common within the disk of our galaxy, this smaller companion galaxy is more primeval in that it lacks a large percentage of the heavier elements that are forged in successive generations of stars through nuclear fusion.

Dwarf galaxies like the SMC are considered primitive building blocks of larger galaxies. Most of these types of galaxies existed far away, when the universe was much younger.

The SMC offers a unique nearby laboratory for understanding how stars arose in the early universe. Nestled among other starburst regions with the small galaxy, the nebula NGC 346 alone contains more than 2,500 infant stars.

The Hubble images, taken with the Advanced Camera for Surveys, identify three stellar populations in the SMC region of NGC 346 � a total of 70,000 stars. The oldest population is 4.5 billion years, roughly the age of our Sun.

The younger population arose only 5 million years ago (about the time Earth�s first hominids began to walk on two feet). Curiously, these infant stars are strung along two intersecting dust lanes in the nebula, resembling a "T" pattern in the Hubble plot.

The stars behind these lanes are coloured reddish-brown due to the effect of reddening caused by the dust.

The observations, by Antonella Nota of the European Space Agency (ESA) and the Space Telescope Science Institute (STScI), Baltimore, USA, are being presented today (Jan 12) at the meeting of the American Astronomical Society in San Diego, California, USA.

The image was composed from two individual exposures taken through a V filter (555 nm, shown in blue) and a near-infrared filter (814 nm, shown in red).

The other science team members are: M. Sirianni (ESA/STScI), E. Sabbi (Univ. of Bologna), M. Tosi (INAF - Bologna Observ.), J.S. Gallagher (Univ. of Wisconsin), M. Meixner (STScI), M. Clampin (GSFC), S. Oey (Univ. of Michigan), A. Pasquali (ETH Zurich), L. Smith (Univ. College London), and R. Walterbos (New Mexico State Univ.).

MILKY WAY

ESA's Hipparcos Finds Rebels With A Cause

Paris, France (ESA) Oct 22, 2004
A team of European astronomers has discovered that many stars in the vicinity of the Sun have unusual motions caused by the spiral arms of our galaxy, the Milky Way. According to this research, based on data from ESA's Hipparcos observatory, our stellar neighbourhood is the crossroads of streams of stars coming from several directions.

Thanks for being here; We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor $5 Billed Once credit card or paypal		SpaceDaily Monthly Supporter $5 Billed Monthly paypal only

The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.