Space Industry and Business News  
STELLAR CHEMISTRY
ALMA uncovers secrets of Giant Space Blob
by Staff Writers
Garching, Germany (SPX) Sep 22, 2016


This rendering shows a snapshot from a cosmological simulation of a Lyman-alpha Blob similar to LAB-1. This simulation tracks the evolution of gas and dark matter using one of the latest models for galaxy formation running on the NASA Pleiades supercomputer. This view shows the distribution of gas within the dark matter halo, colour coded so that cold gas (mainly neutral hydrogen) appears red and hot gas appears white. Embedded at the centre of this system are two strongly star-forming galaxies, but these are surrounded by hot gas and many smaller satellite galaxies that appear as small red clumps of gas here. Lyman-alpha photons escape from the central galaxies and scatter off the cold gas associated with these satellites to give rise to an extended Lyman-alpha Blob. Image courtesy J.Geach/D.Narayanan/R.Crain. For a larger version of this image please go here.

An international team using ALMA, along with ESO's Very Large Telescope and other telescopes, has discovered the true nature of a rare object in the distant universe called a Lyman-alpha blob.

Up to now astronomers did not understand what made these huge clouds of gas shine so brightly, but ALMA has now seen two galaxies at the heart of one of these objects and they are undergoing a frenzy of star formation that is lighting up their surroundings. These large galaxies are in turn at the centre of a swarm of smaller ones in what appears to be an early phase in the formation of a massive cluster of galaxies. The two ALMA sources are expected to evolve into a single giant elliptical galaxy.

Lyman-alpha blobs (LABs) are gigantic clouds of hydrogen gas that can span hundreds of thousands of light-years and are found at very large cosmic distances. The name reflects the characteristic wavelength of ultraviolet light that they emit, known as Lyman-alpha radiation. Since their discovery, the processes that give rise to LABs have been an astronomical puzzle. But new observations with ALMA may now have now cleared up the mystery.

One of the largest Lyman-alpha blobs known, and the most thoroughly studied, is SSA22-Lyman-alpha Blob 1, or LAB-1. Embedded in the core of a huge cluster of galaxies in the early stages of formation, it was the very first such object to be discovered - in 2000 - and is located so far away that its light has taken about 11.5 billion years to reach us.

A team of astronomers, led by Jim Geach, from the Centre for Astrophysics Research of the University of Hertfordshire, UK, has now used the Atacama Large Millimeter/Submillimeter Array's (ALMA) unparalleled ability to observe light from cool dust clouds in distant galaxies to peer deeply into LAB-1. This allowed them to pinpoint and resolve several sources of submillimetre emission.

They then combined the ALMA images with observations from the Multi Unit Spectroscopic Explorer (MUSE) instrument mounted on ESO's Very Large Telescope (VLT), which map the Lyman-alpha light. This showed that the ALMA sources are located in the very heart of the Lyman-alpha blob, where they are forming stars at a rate over 100 times that of the Milky Way.

Deep imaging with the NASA/ESA Hubble Space Telescope and spectroscopy at the W. M. Keck Observatory showed in addition that the ALMA sources are surrounded by numerous faint companion galaxies that could be bombarding the central ALMA sources with material, helping to drive their high star formation rates.

The team then turned to a sophisticated simulation of galaxy formation to demonstrate that the giant glowing cloud of Lyman-alpha emission can be explained if ultraviolet light produced by star formation in the ALMA sources scatters off the surrounding hydrogen gas. This would give rise to the Lyman-alpha blob we see.

Jim Geach, lead author of the new study, explains: "Think of a streetlight on a foggy night - you see the diffuse glow because light is scattering off the tiny water droplets. A similar thing is happening here, except the streetlight is an intensely star-forming galaxy and the fog is a huge cloud of intergalactic gas. The galaxies are illuminating their surroundings."

Understanding how galaxies form and evolve is a massive challenge. Astronomers think Lyman-alpha blobs are important because they seem to be the places where the most massive galaxies in the universe form. In particular, the extended Lyman-alpha glow provides information on what is happening in the primordial gas clouds surrounding young galaxies, a region that is very difficult to study, but critical to understand.

Jim Geach concludes, "What's exciting about these blobs is that we are getting a rare glimpse of what's happening around these young, growing galaxies. For a long time the origin of the extended Lyman-alpha light has been controversial. But with the combination of new observations and cutting-edge simulations, we think we have solved a 15-year-old mystery: Lyman-alpha Blob-1 is the site of formation of a massive elliptical galaxy that will one day be the heart of a giant cluster. We are seeing a snapshot of the assembly of that galaxy 11.5 billion years ago."


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


.


Related Links
European Southern Observatory
Stellar Chemistry, The Universe And All Within It






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

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

Previous Report
STELLAR CHEMISTRY
Astronomers follow twin jets to the center of an active galaxy
Bonn, Germany (UPI) Sep 19, 2016
Astronomers have developed a new method for locating the heart of an active galaxy. In a new study, researchers with the Max Planck Society traced the origin of a pair of relativistic jets by measuring the magnetic field surrounding a supermassive black hole. Previously, researchers have located the centers of galaxies by tracing the wavelengths of relativistic jets to their convergence ... read more


STELLAR CHEMISTRY
UK increases investment in Magna Parva in-space manufacturing tech

Tardigrades use protective protein to shield their DNA from radiation

'Virtual orchestra' hits high notes in London

Study investigates steel-eating microbes on ship hulls

STELLAR CHEMISTRY
SES unveils new tactical surveillance and communications solution

Newest DARPA Challenge: 'Shift Paradigm' With Robot Radio

SES Government solutions to provide the US with a high performance network

The sky's no limit for young space professionals

STELLAR CHEMISTRY
Launch of Atlas V Rocket With WorldView-4 Satellite Postponed Till October

Rocket agreement marks countdown to New Zealand's first space launch

Parallel launch preparations put Ariane 5 on track for next launch

Vega orbits "eyes in the skies" on its latest success

STELLAR CHEMISTRY
SMC exercises contract options to procure two additional GPS III satellites

Lockheed gets $395 million GPS III Space Vehicle contract modification

2 SOPS bids farewell to miracle satellite

China issues development plan for geoinformation industry

STELLAR CHEMISTRY
French fighter jet deal: an Indian saga

India signs deal for acquisition of 36 Rafale fighter jets

Indian ministers approve Rafale fighter jet deal

Sukhoi T-50 jet cannon test-fired in Russia

STELLAR CHEMISTRY
Integrating graphene, reduced graphene oxide onto silicon chips at room temperature

Semiconducting inorganic double helix

One-pot synthesis towards sulfur-based organic semiconductors

Seeing energized light-active molecules proves quick work for Argonne scientists

STELLAR CHEMISTRY
Earth Observation Manufacturing, Data Markets Continue Expansion

Vega to launch ESA's wind mission

METimage: New Weather Data Every 1.7 seconds

Rezatec to develop the use of satellite data in evaluating plant health in UK

STELLAR CHEMISTRY
China ship owners pay up for Australia reef disaster

Southeat Asian haze crisis killed over 100,000: study

ICC prosecutors to step up focus on ecological crimes

Russian metals giant admits red river leak









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - 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. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.