Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Dust pillars of destruction reveal impact of cosmic wind on galaxy evolution

28.07.2015

Astronomers have long known that powerful cosmic winds can sometimes blow through galaxies, sweeping out interstellar material and stopping future star formation. Now they have a clearer snapshot of how it happens.

A Yale University analysis of one such event in a nearby galaxy provides an unprecedented look at the process. The research is described in the Astronomical Journal.


This Hubble Space Telescope image of a spiral galaxy in the Coma cluster highlights dust extinction features.

Image courtesy of NASA, ESA, and Roberto Colombari

Specifically, Yale astronomer Jeffrey Kenney looked at the way the cosmic wind is eroding the gas and dust at the leading edge of the galaxy. The wind, or ram pressure, is caused by the galaxy's orbital motion through hot gas in the cluster. Kenney found a series of intricate dust formations on the disk's edge, as cosmic wind began to work its way through the galaxy.

"On the leading side of the galaxy, all the gas and dust appears to be piled up in one long ridge, or dust front. But you see remarkable, fine scale structure in the dust front," Kenney explained. "There are head-tail filaments protruding from the dust front. We think these are caused by dense gas clouds becoming separated from lower density gas."

Cosmic wind can easily push low-density clouds of interstellar gas and dust, but not high-density clouds. As the wind blows, denser gas lumps start to separate from the surrounding lower density gas which gets blown downstream. But apparently, the high and low-density lumps are partially bound together, most likely by magnetic fields linking distant clouds of gas and dust.

"The evidence for this is that dust filaments in the HST (Hubble Space Telescope) image look like taffy being stretched out," Kenney said. "We're seeing this decoupling, clearly, for the first time."

The analysis is based on Hubble images of a spiral galaxy in the Coma cluster, located 300 million light years from Earth. It is the closest high-mass cluster to our solar system. Kenney first saw the images two years ago and realized their possible significance in understanding the way ram pressure strips interstellar material throughout the universe.

In the 1990s, a famous Hubble photo dubbed "Pillars of Creation" showed columns of dust and gas in the Eagle Nebula that were in the process of forging new stars. The dust filaments Kenney identified are similar in some ways to the "Pillars of Creation," except they are 1,000 times larger.

In both cases, destruction is at least as important as creation. An external force is pushing away most of the gas and dust, therefore destroying most of the cloud, leaving behind only the most dense material -- the pillars. But even the pillars don't last that long.

Because gas is the raw material for star formation, its removal stops the creation of new stars and planets. In the Eagle Nebula, the pressure arises from intense radiation emitted by nearby massive stars; in the Coma galaxy, it is pressure from the galaxy's orbital motion through hot gas in the cluster. Although new stars are being born in both kinds of pillars, we are witnessing, in both, the last generation of stars that will form.

Much of Kenney's research has focused on the physical interplay of galaxies with their environment.

"A great deal of galaxy evolution is driven by interactions," Kenney said. "Galaxies are shaped by collisions and mergers, as well as this sweeping of their gas from cosmic winds. I'm interested in all of these processes."

###

Kenney's co-authors on the paper are Yale doctoral student Anne Abramson and Hector-Bravo Alfaro from the Universidad de Guanajuato in Mexico.

Media Contact

Jim Shelton
james.shelton@yale.edu
203-432-3881

 @yale

http://www.yale.edu 

Jim Shelton | EurekAlert!

More articles from Physics and Astronomy:

nachricht Breaking: the first light from two neutron stars merging
17.10.2017 | American Association for the Advancement of Science

nachricht Filling the early universe with knots can explain why the world is three-dimensional
17.10.2017 | Vanderbilt University

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

Im Focus: New nanomaterial can extract hydrogen fuel from seawater

Hybrid material converts more sunlight and can weather seawater's harsh conditions

It's possible to produce hydrogen to power fuel cells by extracting the gas from seawater, but the electricity required to do it makes the process costly. UCF...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Study suggests oysters offer hot spot for reducing nutrient pollution

17.10.2017 | Life Sciences

Breaking: the first light from two neutron stars merging

17.10.2017 | Physics and Astronomy

World first for reading digitally encoded synthetic molecules

17.10.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>