Featured Research

from universities, journals, and other organizations

Milky Way's Not-so-distant Cousin Likely Harbors Supermassive Black Hole

Date:
September 6, 2009
Source:
ESO
Summary:
Astronomers have taken a striking new image of a nearby galaxy that many astronomers think closely resembles our own Milky Way. Though the galaxy is seen edge-on, observations of NGC 4945 suggest that this hive of stars is a spiral galaxy much like our own, with swirling, luminous arms and a bar-shaped central region. These resemblances aside, NGC 4945 has a brighter center that likely harbors a supermassive black hole, which is devouring reams of matter and blasting energy out into space.

Seen edge-on, observations of NGC 4945 suggest that this hive of stars is a spiral galaxy much like our own Milky Way, with swirling, luminous arms and a bar-shaped centre. Sites of active star formation, known as H II regions, are seen prominently in the image, appearing bright pink. These resemblances aside, NGC 4945 has a brighter centre that likely harbours a supermassive black hole, which is devouring reams of matter and blasting energy out into space. NGC 4945 is about 13 million light-years away in the constellation of Centaurus (the Centaur) and is beautifully revealed in this image taken with data in five bands (B, V, R, H-alpha and S II) with the 2.2-metre MPG/ESO telescope at La Silla. The field of view is 30 x 30 arcminutes. North is up, East is to the left.
Credit: ESO

ESO has released a striking new image of a nearby galaxy that many astronomers think closely resembles our own Milky Way. Though the galaxy is seen edge-on, observations of NGC 4945 suggest that this hive of stars is a spiral galaxy much like our own, with swirling, luminous arms and a bar-shaped central region.

These resemblances aside, NGC 4945 has a brighter centre that likely harbours a supermassive black hole, which is devouring reams of matter and blasting energy out into space.

As NGC 4945 is only about 13 million light-years away in the constellation of Centaurus (the Centaur), a modest telescope is sufficient for skygazers to spot this remarkable galaxy. NGC 4945’s designation comes from its entry number in the New General Catalogue compiled by the Danish–Irish astronomer John Louis Emil Dreyer in the 1880s. James Dunlop, a Scottish astronomer, is credited with originally discovering NGC 4945 in 1826 from Australia.

Today’s new portrait of NGC 4945 comes courtesy of the Wide Field Imager (WFI) instrument at the 2.2-metre MPG/ESO telescope at the La Silla Observatory in Chile. NGC 4945 appears cigar-shaped from our perspective on Earth, but the galaxy is actually a disc many times wider than it is thick, with bands of stars and glowing gas spiralling around its centre. With the use of special optical filters to isolate the colour of light emitted by heated gases such as hydrogen, the image displays sharp contrasts in NGC 4945 that indicate areas of star formation.

Other observations have revealed that NGC 4945 has an active galactic nucleus, meaning its central bulge emits far more energy than calmer galaxies like the Milky Way. Scientists classify NGC 4945 as a Seyfert galaxy after the American astronomer Carl K. Seyfert, who wrote a study in 1943 describing the odd light signatures emanating from some galactic cores.

Since then, astronomers have come to suspect that supermassive black holes cause the turmoil in the centre of Seyfert galaxies. Black holes gravitationally draw gas and dust into them, accelerating and heating this attracted matter until it emits high-energy radiation, including X-rays and ultraviolet light. Most large, spiral galaxies, including the Milky Way, host a black hole in their centres, though many of these dark monsters no longer actively “feed” at this stage in galactic development.


Story Source:

The above story is based on materials provided by ESO. Note: Materials may be edited for content and length.


Cite This Page:

ESO. "Milky Way's Not-so-distant Cousin Likely Harbors Supermassive Black Hole." ScienceDaily. ScienceDaily, 6 September 2009. <www.sciencedaily.com/releases/2009/09/090902112111.htm>.
ESO. (2009, September 6). Milky Way's Not-so-distant Cousin Likely Harbors Supermassive Black Hole. ScienceDaily. Retrieved April 23, 2014 from www.sciencedaily.com/releases/2009/09/090902112111.htm
ESO. "Milky Way's Not-so-distant Cousin Likely Harbors Supermassive Black Hole." ScienceDaily. www.sciencedaily.com/releases/2009/09/090902112111.htm (accessed April 23, 2014).

Share This



More Space & Time News

Wednesday, April 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nuclear-Level Asteroids Might Be More Common Than We Realize

Nuclear-Level Asteroids Might Be More Common Than We Realize

Newsy (Apr. 23, 2014) The B612 Foundation says asteroids strike Earth much more often than previously thought, and are hoping to build an early warning system. Video provided by Newsy
Powered by NewsLook.com
NASA Chief Outlines Plan for Human Mission to Mars

NASA Chief Outlines Plan for Human Mission to Mars

AFP (Apr. 22, 2014) NASA administrator Charles Bolden, speaking at the 'Human to Mars Summit' in Washington, says that learning more about the Red Planet can help answer the 'fundamental question' of 'life beyond Earth'. Duration: 00:48 Video provided by AFP
Powered by NewsLook.com
Nasa Gives You An Excuse to Post a Selfie on Earth Day

Nasa Gives You An Excuse to Post a Selfie on Earth Day

TheStreet (Apr. 22, 2014) NASA is inviting all social media users to take a selfie of themselves alongside nature and to post it to Twitter, Facebook, Flickr, Instagram, or Google Plus with the hashtag #globalselfie. NASA's goal is to crowd-source a collection of snapshots of the earth, ground-up, that will be used to create one "unique mosaic of the Blue Marble." This image will be available to all in May. Since this is probably one of the few times posting a selfie to Twitter won't be embarrassing, we suggest you give it a go for a good cause. Video provided by TheStreet
Powered by NewsLook.com
SpaceX's Dragon Spacecraft Captured by International Space Station

SpaceX's Dragon Spacecraft Captured by International Space Station

Reuters - US Online Video (Apr. 20, 2014) SpaceX's unmanned Dragon spacecraft makes a scheduled Easter Sunday rendezvous with the International Space Station. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

    Environment News

    Technology News



    Save/Print:
    Share:

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile: iPhone Android Web
    Follow: Facebook Twitter Google+
    Subscribe: RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins