Featured Research

from universities, journals, and other organizations

Ninety-six star clusters discovered hidden behind dust of Milky Way

Date:
August 4, 2011
Source:
European Southern Observatory - ESO
Summary:
Astronomers have discovered 96 new open star clusters hidden by the dust in the Milky Way. These tiny and faint objects were invisible to previous surveys, but they could not escape the sensitive infrared detectors of the world's largest survey telescope, which can peer through the dust. This is the first time so many faint and small clusters have been found at once.

Using data from the VISTA infrared survey telescope at ESO's Paranal Observatory, an international team of astronomers has discovered 96 new open clusters hidden by the dust in the Milky Way. Thirty of these clusters are shown in this mosaic. These tiny and faint objects were invisible to previous surveys, but they could not escape the sensitive infrared detectors of the world's largest survey telescope, which can peer through the dust. This is the first time so many faint and small clusters have been found at once. The images are made using infrared light in the following bands: J (shown in blue), H (shown in green), and Ks (shown in red).
Credit: ESO/J. Borissova

Using data from the VISTA infrared survey telescope at the European Southern Observatory's Paranal Observatory, an international team of astronomers has discovered 96 new open star clusters hidden by the dust in the Milky Way. These tiny and faint objects were invisible to previous surveys, but they could not escape the sensitive infrared detectors of the world's largest survey telescope, which can peer through the dust. This is the first time so many faint and small clusters have been found at once.

This result comes just one year after the start of the VISTA Variables in the Via Lactea programme (VVV)*, one of the six public surveys on the new telescope. The results will appear in the journal Astronomy & Astrophysics.

"This discovery highlights the potential of VISTA and the VVV survey for finding star clusters, especially those hiding in dusty star-forming regions in the Milky Way's disc. VVV goes much deeper than other surveys," says Jura Borissova, lead author of the study.

The majority of stars with more than half of the mass of our Sun form in groups, called open clusters. These clusters are the building blocks of galaxies and vital for the formation and evolution of galaxies such as our own. However, stellar clusters form in very dusty regions that diffuse and absorb most of the visible light that the young stars emit, making them invisible to most sky surveys, but not to the 4.1-m infrared VISTA telescope.

"In order to trace the youngest star cluster formation we concentrated our search towards known star-forming areas. In regions that looked empty in previous visible-light surveys, the sensitive VISTA infrared detectors uncovered many new objects," adds Dante Minniti, lead scientist of the VVV survey.

By using carefully tuned computer software, the team was able to remove the foreground stars appearing in front of each cluster in order to count the genuine cluster members. Afterwards, they made visual inspections of the images to measure the cluster sizes, and for the more populous clusters they made other measurements such as distance, age, and the amount of reddening of their starlight caused by interstellar dust between them and us.

"We found that most of the clusters are very small and only have about 10-20 stars. Compared to typical open clusters, these are very faint and compact objects -- the dust in front of these clusters makes them appear 10 000 to 100 million times fainter in visible light. It's no wonder they were hidden," explains Radostin Kurtev, another member of the team.

Since antiquity only 2500 open clusters have been found in the Milky Way, but astronomers estimate there might be as many as 30 000 still hiding behind the dust and gas. While bright and large open clusters are easily spotted, this is the first time that so many faint and small clusters have been found at once.

Furthermore, these new 96 open clusters could be only the tip of the iceberg. "We've just started to use more sophisticated automatic software to search for less concentrated and older clusters. I am confident that many more are coming soon," adds Borissova.

*Since 2010, the VISTA Variables in the Via Lactea programme (VVV) has been scanning the central parts of the Milky Way and the southern plane of the galactic disc in infrared light. This program was granted a total of 1929 hours of observing time over a five year period. Via Lactea is the Latin name for the Milky Way.


Story Source:

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


Journal Reference:

  1. Dante Minniti et al. New Galactic Star Clusters in the VVV Survey. Astronomy & Astrophysics, 2011 (in press)

Cite This Page:

European Southern Observatory - ESO. "Ninety-six star clusters discovered hidden behind dust of Milky Way." ScienceDaily. ScienceDaily, 4 August 2011. <www.sciencedaily.com/releases/2011/08/110803083642.htm>.
European Southern Observatory - ESO. (2011, August 4). Ninety-six star clusters discovered hidden behind dust of Milky Way. ScienceDaily. Retrieved September 21, 2014 from www.sciencedaily.com/releases/2011/08/110803083642.htm
European Southern Observatory - ESO. "Ninety-six star clusters discovered hidden behind dust of Milky Way." ScienceDaily. www.sciencedaily.com/releases/2011/08/110803083642.htm (accessed September 21, 2014).

Share This



More Space & Time News

Sunday, September 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

MIT BioSuit A New Take On Traditional Spacesuits

MIT BioSuit A New Take On Traditional Spacesuits

Newsy (Sep. 19, 2014) The MIT BioSuit could be an alternative to big, bulky traditional spacesuits, but the concept needs some work. Video provided by Newsy
Powered by NewsLook.com
Boeing, SpaceX to Send Astronauts to Space Station

Boeing, SpaceX to Send Astronauts to Space Station

AFP (Sep. 17, 2014) NASA selected Boeing and SpaceX on Tuesday to build America's next spacecraft to carry astronauts to the International Space Station (ISS) by 2017, opening the way to a new chapter in human spaceflight. Duration: 01:13 Video provided by AFP
Powered by NewsLook.com
East Coast Treated To Rare Meteor Sighting

East Coast Treated To Rare Meteor Sighting

Newsy (Sep. 16, 2014) Numerous residents along the East Coast reported seeing a bright meteor flash through the sky Sunday night. Video provided by Newsy
Powered by NewsLook.com
Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. 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