Subscribe to our free daily newsletters
. 24/7 Space News .




Subscribe to our free daily newsletters



STELLAR CHEMISTRY
Milky Way's origins are not what they seem
by Staff Writers
Chicago IL (SPX) Jul 27, 2017


Pair of nearby galaxies with possible intergalactic transfer: This image shows M81 (bottom right) and M82 (upper left), a pair of nearby galaxies where 'intergalactic transfer' may be happening. Gas ejected by supernova explosions in M82 can travel through space and eventually contribute to the growth of M81. Credit Fred Herrmann, 2014

In a first-of-its-kind analysis, Northwestern University astrophysicists have discovered that, contrary to previously standard lore, up to half of the matter in our Milky Way galaxy may come from distant galaxies. As a result, each one of us may be made in part from extragalactic matter.

Using supercomputer simulations, the research team found a major and unexpected new mode for how galaxies, including our own Milky Way, acquired their matter: intergalactic transfer.

The simulations show that supernova explosions eject copious amounts of gas from galaxies, which causes atoms to be transported from one galaxy to another via powerful galactic winds. Intergalactic transfer is a newly identified phenomenon, which simulations indicate will be critical for understanding how galaxies evolve.

"Given how much of the matter out of which we formed may have come from other galaxies, we could consider ourselves space travelers or extragalactic immigrants," said Daniel Angles-Alcazar, a postdoctoral fellow in Northwestern's astrophysics center, CIERA (Center for Interdisciplinary Exploration and Research in Astrophysics), who led the study.

"It is likely that much of the Milky Way's matter was in other galaxies before it was kicked out by a powerful wind, traveled across intergalactic space and eventually found its new home in the Milky Way."

Galaxies are far apart from each other, so even though galactic winds propagate at several hundred kilometers per second, this process occurred over several billion years.

Professor Claude-Andre Faucher-Giguere and his research group, along with collaborators from the FIRE ("Feedback In Realistic Environments") project, which he co-leads, had developed sophisticated numerical simulations that produced realistic 3-D models of galaxies, following a galaxy's formation from just after the Big Bang to the present day. Angles-Alcazar then developed state-of-the-art algorithms to mine this wealth of data and quantify how galaxies acquire matter from the universe.

The study, which required the equivalent of several million hours of continuous computing, will be published July 26 (July 27 in the U.K.) by the Monthly Notices of the Royal Astronomical Society.

"This study transforms our understanding of how galaxies formed from the Big Bang," said Faucher-Giguere, a co-author of the study and assistant professor of physics and astronomy in the Weinberg College of Arts and Sciences.

"What this new mode implies is that up to one-half of the atoms around us - including in the solar system, on Earth and in each one of us - comes not from our own galaxy but from other galaxies, up to one million light years away," he said.

By tracking in detail the complex flows of matter in the simulations, the research team found that gas flows from smaller galaxies to larger galaxies, such as the Milky Way, where the gas forms stars. This transfer of mass through galactic winds can account for up to 50 percent of matter in the larger galaxies.

"In our simulations, we were able to trace the origins of stars in Milky Way-like galaxies and determine if the star formed from matter endemic to the galaxy itself or if it formed instead from gas previously contained in another galaxy," said Angles-Alcazar, the study's corresponding author.

In a galaxy, stars are bound together: a large collection of stars orbiting a common center of mass. After the Big Bang 14 billion years ago, the universe was filled with a uniform gas - no stars, no galaxies. But there were tiny perturbations in the gas, and these started to grow by force of gravity, eventually forming stars and galaxies. After galaxies formed, each had its own identity.

"Our origins are much less local than we previously thought," said Faucher-Giguere, a CIERA member. "This study gives us a sense of how things around us are connected to distant objects in the sky."

The findings open a new line of research in understanding galaxy formation, the researchers say, and the prediction of intergalactic transfer can now be tested. The Northwestern team plans to collaborate with observational astronomers who are working with the Hubble Space Telescope and ground-based observatories to test the simulation predictions.

The simulations were run and analyzed using the National Science Foundation's Extreme Science and Engineering Discovery Environment supercomputing facilities, as well as Northwestern's Quest high-performance computer cluster.

"The Cosmic Baryon Cycle and Galaxy Mass Assembly in the FIRE Simulations." In addition to Angles-Alcazar and Faucher-Giguere, other authors include Dusan Keres (University of California, San Diego), Philip F. Hopkins (Caltech), Eliot Quataert (University of California, Berkeley) and Norman Murray (Canadian Institute for Theoretical Astrophysics).

STELLAR CHEMISTRY
New Ways Developed to See the Formation of Stars in the Milky Way
Chicago IL (SPX) Jul 21, 2017
A research team led by Adler Planetarium astronomer Dr. Grace Wolf-Chase has discovered new evidence of stars forming in our Milky Way Galaxy. By using a telescope equipped to detect infrared light invisible to our eyes, this exciting new science is revealing how stars, including our very own Sun, grow up within clusters and groups. The Astrophysical Journal has published a paper on the subject ... read more

Related Links
Northwestern University
Stellar Chemistry, The Universe And All Within It


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

Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

STELLAR CHEMISTRY
Soyuz rocket rolled out, ready to launch

Astronauts gear up for space with tough Russian training

Russian sanctions won't affect cooperation in space

NASA Offers Space Station as Catalyst for Discovery in Washington

STELLAR CHEMISTRY
Vega to launch two Earth Observation Satellites for Italy, Israel and France

Three Up, Three Down as NASA Tests RS-25 Flight Controller

Iran in 'successful' test of satellite-launch rocket

Aerojet Rocketdyne's RS-25 Flight Controller Goes Three for Three in SLS Test

STELLAR CHEMISTRY
Portals to new worlds: Martian exploration near the North Pole

For Moratorium on Sending Commands to Mars, Blame the Sun

Tributes to wetter times on Mars

Opportunity will spend three weeks at current location due to Solar Conjunction

STELLAR CHEMISTRY
China develops sea launches to boost space commerce

Chinese satellite Zhongxing-9A enters preset orbit

Chinese Space Program: From Setback, to Manned Flights, to the Moon

Chinese Rocket Fizzles Out, Puts Other Launches on Hold

STELLAR CHEMISTRY
Good Night, Lisa Pathfinder

A Final Farewell to LISA Pathfinder

ASTROSCALE Raises a Total of $25 Million in Series C Led by Private Companies

LISA Pathfinder: bake, rattle and roll

STELLAR CHEMISTRY
Multitasking monolayers

Writing with the electron beam: Now in silver

Scientists announce the quest for high-index materials

A new synthesis route for alternative catalysts of noble metals

STELLAR CHEMISTRY
SETI Institute-Unistellar Partnership Promises to Revolutionize Amateur Astronomy

Holographic imaging could sample and identify living microbes in the outer solar system

Why looking for aliens is good for society

Breakthrough Starshot launches tiny spacecraft in quest for Alpha Centauri

STELLAR CHEMISTRY
New Horizons Video Soars over Pluto's Majestic Mountains and Icy Plains

Juno spots Jupiter's Great Red Spot

New evidence in support of the Planet Nine hypothesis

NASA's New Horizons Team Strikes Gold in Argentina




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - 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. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. 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