Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. 24/7 Space News .




STELLAR CHEMISTRY
Shedding Light on the Power of M 82's Superwinds
by Staff Writers
Tokyo, Japan (SPX) Jan 25, 2013


Sketches of possible ionization sources of M 82's cap. left: Ultraviolet photons from massive stars in the M 82 starburst region. right: Ultraviolet photons from shockwaves caused by the collision between M 82's galactic winds and gas clouds. (Credit: NAOJ).

An international team of astronomers, led by Dr. Kazuya Matsubayshi (Kyoto University), has discovered that outflows of gas from starburst galaxy M 82 (see Note 1 for a reference figure) collide with a "cap" of gas clouds 40,000 light years away from the galactic disk.

Shockwaves (Note 2) from M 82's central starburst region are the most likely source of the bright clouds within the cap. The large light-gathering power of Subaru Telescope's 8.2-m mirror and its ability to produce highly detailed images enabled the researchers to make these findings, which provide important clues about the wind's power.

The central regions of starburst galaxies are sites of immense star formation. They give birth to thousands of massive stars, which are dozens of times heavier than the Sun and then explode as supernovae when they die. Many supernovae explosions heat the gas around them to temperatures of more than a million degrees, and this hot gas flows out from the galaxy as galactic wind.

These winds are so powerful that they may play an important role in the evolution of galaxies and the inter-galactic medium. However, galactic winds are usually diffuse and difficult to observe; therefore, it has been difficult to confirm their power. Nevertheless, it is possible to precisely estimate their energy level by measuring how far the galactic winds reach.

The current team tackled the issue of shedding light on the processes behind large-scale galactic winds by focusing their research on the "cap" of M 82, one of the closest starburst galaxies to Earth, about 12 million light years away.

M 82 has large-scale galactic winds, so-called "superwinds", and its cap consists of gas clouds about 40,000 light years away from its galactic disk. Matsubayashi pinpointed the research question: "Why are there ionized gas clouds so far from the galactic disk? If we investigate the ionization source of the cap, we can confirm whether M 82's galactic winds reach it."

Two possibilities for ionization sources of M 82's cap are: 1) ultraviolet photons from massive stars in M 82's starburst regions and 2) shockwaves caused by the collision of M 82's galactic winds with gas clouds in the cap (Figure 1).

The researchers reasoned, "Because we can estimate the intensity of ultraviolet photons from the starburst regions and the pressure of the galactic winds from past observational data, the morphology and H-alpha (Note 3) intensity of the cap region will reveal the answer."

The team investigated the ionization source of M 82's cap by observing it with Kyoto 3DII mounted on the Subaru Telescope. They used the Fabry-Perot interferometer, which works as a narrow-band filter that researchers can tune for a desired wavelength. They obtained images of continuum and H-alpha emissions of the cap.

If UV light from the M 82 starburst regions ionized the clumps of the cap, the H-alpha emission should be ten times weaker than what was observed. In contrast, the H-alpha intensity predicted by the shock model matches well with the measurement from the observations.

Therefore, the team concluded that shockwaves from M 82's galactic winds ionized the gas clouds in the cap. This suggests that the galactic winds travel and have direct impacts on inter-galactic gas at least 40,000 light years away from the galactic disk.

The research raises another question: "Do galactic winds affect gas clouds at an even further distance from the galactic disk?" Matsubayashi remarked, "We would like to carry out observations to survey more distant gas clouds ionized by galactic winds."

The scientific results on which this release was based were published in the December 10, 2012 edition of The Astrophysical Journal: K. Matsubayashi et al., "Ionization Source of a Minor-Axis Cloud in the Outer Halo of M 82", 761:55 (8pp).

.


Related Links
Subaru
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




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





STELLAR CHEMISTRY
A hidden treasure in the Large Magellanic Cloud
Paris (ESA) Jan 25, 2013
Nearly 200 000 light-years from Earth, the Large Magellanic Cloud, a satellite galaxy of the Milky Way, floats in space, in a long and slow dance around our galaxy. Vast clouds of gas within it slowly collapse to form new stars. In turn, these light up the gas clouds in a riot of colours, visible in this image from the NASA/ESA Hubble Space Telescope. The Large Magellanic Cloud (LMC) is ab ... read more


STELLAR CHEMISTRY
US, Europe team up for moon fly-by

Russia to Launch Lunar Mission in 2015

US, Europe team up for moon fly-by

Mission would drag asteroid to the moon

STELLAR CHEMISTRY
Opportunity At Work At Whitewater Lake

Thawing Dry Ice Drives Groovy Action On Mars

Mars Rover Curiosity Uses Arm Camera at Night

Possible Clues to Ancient Subsurface Biosphere on Mars

STELLAR CHEMISTRY
Iran Manufacturing Hi-Tech Spacesuits

TDRS-K Offers Upgrade to Vital Communications Net

An Astronaut's Guide

Mathematical breakthrough sets out rules for more effective teleportation

STELLAR CHEMISTRY
Reshuffle for Tiangong

China to launch 20 spacecrafts in 2013

Mr Xi in Space

China plans manned space launch in 2013: state media

STELLAR CHEMISTRY
NASA to Send Inflatable Pod to International Space Station

ISS to get inflatable module

ESA workhorse to power NASA's Orion spacecraft

Competition Hopes To Fine Tune ISS Solar Array Shadowing

STELLAR CHEMISTRY
Azerspace And Africasat-1a "fit" for Ariane 5 launch

NASA Selects Experimental Commercial Suborbital Flight Payloads

Payload elements come together in Starsem's wrap-up Soyuz mission from Baikonur Cosmodrome for Globalstar

Amazonas 3 in Kourou for Ariane 5 year-opening launch campaign

STELLAR CHEMISTRY
New Evidence Indicates Auroras Occur Outside Our Solar System

Glitch has space telescope shut down

Earth-size planets common in galaxy

NASA's Hubble Reveals Rogue Planetary Orbit For Fomalhaut B

STELLAR CHEMISTRY
New information on binding gold particles over metal oxide surfaces

Researchers Create Method for More Sensitive Electrochemical Sensors

Phoenix Rising: New Video Shows Advances in Satellite Repurposing Program

Novel sensor provides bigger picture




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal 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. 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