Satellite galaxies of Centaurus A are on a coordinated dance

The satellite dwarf galaxies orbiting around the much larger galaxy Centaurus A are rotating in synchrony around their host, to researchers' surprise. (Researchers expected them to orbit at random).

The results contradict simulations based on standard cosmology, which predict that fewer than 1% of satellite systems should exhibit this synchronous behavior. Because our own Milky Way and the neighboring Andromeda Galaxy also have similar arrangements of coherently orbiting satellite galaxies, this finding suggests that standard cosmological simulations may be wrong.

Current theories of galaxy formation, based on standard cosmological ingredients such as dark matter, predict that small dwarf satellite galaxies should orbit in random positions and directions around their closest large galaxy.

Oliver Muller et al. analyzed the satellite galaxies around Centaurus A, a nearby large elliptical galaxy. They found that the satellite galaxies are not only arranged in a single plane, but the plane also rotates coherently: satellite galaxies on one side of Centaurus A are approaching, while those on the other side are receding.

Of the 16 satellite galaxies for which scientists have data, 14 followed this organized movement - and yet the probability of such a scenario is a mere 0.5% based on simulations, the authors say. These results hint that widely accepted models of cosmology and/or galaxy formation are lacking, or at least misconstruing crucial components.

In a related Perspective, Michael Boylan-Kolchin writes, "The results may lead to either a better understanding of galaxy formation within the [cold dark matter] model or a push to overthrow its underlying assumptions."

Research paper

Related Links
American Association for the Advancement of Science
Stellar Chemistry, The Universe And All Within It

Tweet

Thanks for being there;
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 Monthly Supporter
$5+ Billed Monthly

paypal only

SpaceDaily Contributor
$5 Billed Once

credit card or paypal

Research will help scientists understand how stars create elements
Canberra, Australia (SPX) Feb 13, 2018
New research involving The Australian National University (ANU) has, for the first time, demonstrated a long-theorised nuclear effect, in a feat that will help scientists understand how stars evolve and produce elements such as gold and platinum. Physicists first predicted the effect, called Nuclear Excitation by Electron Capture (NEEC), more than 40 years ago, but this research was the first positive observation and has achieved the first quantified measurement of the phenomenon. Co-researc ... read more