Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Mining Data Archives Yields Haul of "Red Nuggets"


The world of astronomy has changed. An astronomer used to have to travel to a remote location and endure long, cold nights, patiently guiding a telescope to collect precious photons of light. Now, a proliferation of online archives allows astronomers to make discoveries from the comfort of their own offices.

By mining such archives, a team of astronomers led by Ivana Damjanov of the Harvard-Smithsonian Center for Astrophysics (CfA) has found a treasure trove of "red nugget" galaxies.These galaxies are compact and densely packed with old, red stars.

Their abundance provides new constraints on theoretical models of galaxy formation and evolution.s research today at a meeting of the Canadian Astronomical Society (CASCA) in Quebec, QC.When the universe was young, dense, massive galaxies nicknamed "red nuggets" were common.

These galaxies are ten times more massive than the Milky Way, but their stars are packed into a volume a hundred times smaller than our Galaxy.Mysteriously, astronomers searching the older, nearer universe could not find any of these objects.Their apparent disappearance, if real, signaled a surprising turn in galaxy evolution.

To find nearby examples, Damjanov and her colleagues Margaret Geller, Ho Seong Hwang, and Igor Chilingarian (Smithsonian Astrophysical Observatory) combed through the database of the largest survey of the universe, the Sloan Digital Sky Survey.The red nugget galaxies are so small that they appear like stars in Sloan photographs, due to blurring from Earth’s atmosphere.

However, their spectra give away their true nature.The team identified several hundred red nugget candidates in the Sloan data.Then they searched a variety of online telescope archives in order to confirm their findings. In particular, high-quality images from the Canada-France-Hawaii Telescope and the Hubble Space Telescope showed that about 200 of the candidates were galaxies very similar to their red-nugget cousins in the distant, young universe.

"Now we know that many of these amazingly small, dense, but massive galaxies survive. They are a fascinating test of our understanding of the way galaxies form and evolve," explains Geller.The large number of red nuggets discovered in Sloan told the team how abundant those galaxies were in the middle-aged universe.

That number then can be compared to computer models of galaxy formation. Different models for the way galaxies grow predict very different abundances.The picture that matches the observations is one where red nuggets begin their lives as very small objects in the young universe. During the next ten billion years some of them collide and merge with other, smaller and less massive galaxies.

Some red nuggets manage to avoid collisions and remain compact as they age.The result is a variety of elliptical galaxies with different sizes and masses, some very compact and some more extended."Many processes work together to shape the rich landscape of galaxies we see in the nearby universe," says Damjanov.Headquartered in Cambridge, Mass., the Harvard-Smithsonian Center for Astrophysics (CfA) is a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, organized into six research divisions, study the origin, evolution and ultimate fate of the universe.

For more information, contact:

David A. Aguilar
Director of Public Affairs
Harvard-Smithsonian Center for Astrophysics

Christine Pulliam
Public Affairs Specialist
Harvard-Smithsonian Center for Astrophysics

Leslie Sage
Canadian Astronomical Society

Christine Pulliam | Eurek Alert!
Further information:

Further reports about: Archives Astronomical Harvard-Smithsonian Observatory Telescope galaxies

More articles from Physics and Astronomy:

nachricht Listening to the Extragalactic Radio
13.10.2015 | Max-Planck-Institut für Radioastronomie

nachricht Scientists paint quantum electronics with beams of light
12.10.2015 | University of Chicago

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: Secure data transfer thanks to a single photon

Physicists of TU Berlin and mathematicians of MATHEON are so successful that even the prestigious journal “Nature Communications” reported on their project.

Security in data transfer is an important issue, and not only since the NSA scandal. Sometimes, however, the need for speed conflicts to a certain degree with...

Im Focus: A Light Touch May Help Animals and Robots Move on Sand and Snow

Having a light touch can make a hefty difference in how well animals and robots move across challenging granular surfaces such as snow, sand and leaf litter. Research reported October 9 in the journal Bioinspiration & Biomimetics shows how the design of appendages – whether legs or wheels – affects the ability of both robots and animals to cross weak and flowing surfaces.

Using an air fluidized bed trackway filled with poppy seeds or glass spheres, researchers at the Georgia Institute of Technology systematically varied the...

Im Focus: Reliable in-line inspections of high-strength automotive body parts within seconds

Nondestructive material testing (NDT) is a fast and effective way to analyze the quality of a product during the manufacturing process. Because defective materials can lead to malfunctioning finished products, NDT is an essential quality assurance measure, especially in the manufacture of safety-critical components such as automotive B-pillars. NDT examines the quality without damaging the component or modifying the surface of the material. At this year's Blechexpo trade fair in Stuttgart, Fraunhofer IZFP will have an exhibit that demonstrates the nondestructive testing of high-strength automotive body parts using 3MA. The measurement results are available in a matter of seconds.

To minimize vehicle weight and fuel consumption while providing the highest level of crash safety, automotive bodies are reinforced with elements made from...

Im Focus: Kick-off for a new era of precision astronomy

The MICADO camera, a first light instrument for the European Extremely Large Telescope (E-ELT), has entered a new phase in the project: by agreeing to a Memorandum of Understanding, the partners in Germany, France, the Netherlands, Austria, and Italy, have all confirmed their participation. Following this milestone, the project's transition into its preliminary design phase was approved at a kick-off meeting held in Vienna. Two weeks earlier, on September 18, the consortium and the European Southern Observatory (ESO), which is building the telescope, have signed the corresponding collaboration agreement.

As the first dedicated camera for the E-ELT, MICADO will equip the giant telescope with a capability for diffraction-limited imaging at near-infrared...

Im Focus: Locusts at the wheel: University of Graz investigates collision detector inspired by insect eyes

Self-driving cars will be on our streets in the foreseeable future. In Graz, research is currently dedicated to an innovative driver assistance system that takes over control if there is a danger of collision. It was nature that inspired Dr Manfred Hartbauer from the Institute of Zoology at the University of Graz: in dangerous traffic situations, migratory locusts react around ten times faster than humans. Working together with an interdisciplinary team, Hartbauer is investigating an affordable collision detector that is equipped with artificial locust eyes and can recognise potential crashes in time, during both day and night.

Inspired by insects

All Focus news of the innovation-report >>>



Event News

EHFG 2015: Securing healthcare and sustainably strengthening healthcare systems

01.10.2015 | Event News

Conference in Brussels: Tracking and Tracing the Smallest Marine Life Forms

30.09.2015 | Event News

World Alzheimer`s Day – Professor Willnow: Clearer Insights into the Development of the Disease

17.09.2015 | Event News

Latest News

Smart clothing, mini-eyes, and a virtual twin – Artificial Intelligence at ICT 2015

13.10.2015 | Trade Fair News

Listening to the Extragalactic Radio

13.10.2015 | Physics and Astronomy

Penn study stops vision loss in late-stage canine X-linked retinitis pigmentosa

13.10.2015 | Health and Medicine

More VideoLinks >>>