Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The dark side of the fluffiest galaxies

24.05.2016

A team of International astronomers, led by members of the Instituto de Astrofísica de Canarias, has measured for the first time the mass of an ultra-diffuse galaxy using the Gran Telescopio CANARIAS

Galaxies, in all their forms from spirals to ellipticals from giants to dwarfs have been widely studied over the past Century. To the surprise of the scientific community last year a new type of galaxy was discovered, residing in a galactic megalopolis known as the Coma Cluster, some 300 million light years away from Earth.


This is a region of the Virgo cluster of galaxies containing the ultra-diffuse galaxy VCC 1287. The main image is 500 thousand light years across, uses a negative image for contrast, and was obtained with a 10-centimetre diameter amateur telescope in Switzerland (Antares Observatory). The zoom-in colour-composite image of VCC 1287 is from the 4-metre Canada-France- Hawai'i telescope. The coloured symbols show globular star clusters targeted for orbital speed measurements with the 10-metre Gran Telescopio CANARIAS (GTC).

Credit: IAC

Even though they are very numerous, these ultradiffuse galaxies have not been noticed until now because they are very fain. Their stars as spread over a very large area, which makes it particularly difficult to distinguish them from the sky background.

"These galaxies are particularly interesting, given that the violent environment in which they are situation would have destroyged them long ago were they not protected by a large amount of dark matter" says Michael Beasley, the first author or the article published in the journal Astrophysical Journal Letters. "To test this fascinating idea was possible after identifying an ultradiffuse galaxy near enough to study in detail."

This galaxy, VCC 1287, is situated in the Virgo Cluster, some 50 million light years away, and it is surrounded by a swarm of globula clusters, which have proved the key to study its dark matter content. " Globular clusters,made up of hundreds of thousands of stars, orbit within the gravitational field of the ultradiffuse galaxy," adds Aaron Romanowsky of San José State University (USA) one of the authors of the article. "The heavier is a galaxy, the more rapidly its globular clusters move, so they can be used as a cosmic balance."

Using the Gran Telescopio CANARIAS (GTC) the team found that these globular clusters move at high velocity, pulled by a surprisingly strong gravitational field. "Even though dark matter is present in other galaxies, this is an exceptional case" concludes Beasley. "For each kilogramme of ordinary material VCC 1287 contains 3 tonnes of dark matter."

So we can say that ultradiffuse galaxies are essentially composed of dark matter, with very few stars". This conclusion gives the scientists another question "How is it possible for galaxies so diffuse and dark to exist?"

###

Article: "An overmassive dark halo around an ultra-diffuse galaxy in the Virgo cluster", by Michael Beasley (IAC-ULL), Aaron J. Romanowsky (San José State University-University of California Observatories), Vincenzo Pota (INAF, Osservatorio Astronomico di Capodimonte), Ignacio Martín Navarro (IAC-ULL-University of California Observatories), David Martínez Delgado (Universitat Heidelberg), Fabian Neyer ETH Zurich) y Aaron L. Deich (San José State University), 2016, ApJ Letters, 819, L20.

Media Contact

Elena Mora
emora@iac.es

http://www.iac.es/?lang=en 

Elena Mora | EurekAlert!

More articles from Physics and Astronomy:

nachricht New type of low-energy nanolaser that shines in all directions
18.12.2018 | Eindhoven University of Technology

nachricht NASA research reveals Saturn is losing its rings at 'worst-case-scenario' rate
18.12.2018 | NASA/Goddard Space Flight Center

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: Data storage using individual molecules

Researchers from the University of Basel have reported a new method that allows the physical state of just a few atoms or molecules within a network to be controlled. It is based on the spontaneous self-organization of molecules into extensive networks with pores about one nanometer in size. In the journal ‘small’, the physicists reported on their investigations, which could be of particular importance for the development of new storage devices.

Around the world, researchers are attempting to shrink data storage devices to achieve as large a storage capacity in as small a space as possible. In almost...

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Pressure tuned magnetism paves the way for novel electronic devices

18.12.2018 | Materials Sciences

New type of low-energy nanolaser that shines in all directions

18.12.2018 | Physics and Astronomy

NASA research reveals Saturn is losing its rings at 'worst-case-scenario' rate

18.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>