New 'alien' invaders found in the Milky Way: Queen's University astronomer
As many as one quarter of the star clusters in our Milky Way – many more than previously thought – are invaders from other galaxies, according to a new study. The report also suggests there may be as many as six dwarf galaxies yet to be discovered within the Milky Way rather than the two that were previously confirmed.
"Some of the stars and star clusters you see when you look into space at night are aliens from another galaxy, just not the green-skinned type you find in a Hollywood movie. These 'alien' star clusters that have made their way into our galaxy over the last few billion years," says Terry Bridges, an astronomer at Queen's University in Kingston, Canada.
The study (co-authored by Duncan Forbes of Swinburne University of Technology in Australia) has been accepted for publication in the Monthly Notices of the Royal Astronomical Society.
Previously, astronomers had suspected that some star clusters, which contain from 100,000 to a million stars each, were foreign to our galaxy, but it was difficult to identify which ones.
Using mostly Hubble Space Telescope data, Mr. Bridges and Mr. Forbes examined old star clusters within the Milky Way galaxy. From the research they compiled the largest ever high-quality database to record the age and chemical properties of each of these clusters.
"We looked at all the data we could find. The best data are from the Hubble Telescope because it has the best imaging," Bridges says. "We looked at the ages and the amounts of heavy elements in these clusters, which can be measured from their stars."
The researchers' work also suggests that the Milky Way may have swallowed-up more dwarf galaxies than was previously thought. They found that many of the foreign clusters originally existed within dwarf galaxies – 'mini' galaxies of up to 100 million stars that sit within our larger Milky Way. The study suggests that there are more of these accreted dwarf galaxies in our Milky Way than was thought.
The research paper can be found at: http://arxiv.org/pdf/1001.4289v1.
Michael Onesi | EurekAlert!
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...