They may be little, but they pack a big star-forming punch. New observations from NASA's Hubble Space Telescope show small galaxies, also known as dwarf galaxies, are responsible for forming a large proportion of the universe's stars.
Studying this early epoch of the universe's history is critical to fully understanding how these stars formed and how galaxies grew and evolved 3.5 to 6 billion years after the beginning of the universe. The result supports a decade-long investigation into whether there is a link between a galaxy's mass and its star-forming activity, and helps paint a consistent picture of events in the early universe.
Hiding among these thousands of galaxies are faint dwarf galaxies residing in the early universe, between 2 and 6 billion years after the big bang, an important time period when most of the stars in the universe were formed. Some of these galaxies are undergoing starbursts.
Image Credit: NASA and ESA
"We already suspected these kinds of galaxies would contribute to the early wave of star formation, but this is the first time we've been able to measure the effect they actually had," said Hakim Atek of the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland, lead author of the study published in the June 19 online issue of The Astrophysical Journal. "They appear to have had a surprisingly huge role to play."
Previous studies of star-forming galaxies were restricted to the analysis of mid- or high-mass galaxies, leaving out the numerous dwarf galaxies that existed in this era of prolific star formation. Astronomers conducted a recent study using data from Hubble's Wide Field Camera 3 (WFC3) to take a further and significant step forward in understanding this formative era by examining a sample of starburst galaxies in the young universe. Starburst galaxies form stars at a furiously fast rate, far above what is considered by experts to be a normal rate of star formation.
The infrared capabilities of WFC3 have allowed astronomers to finally calculate how much these low-mass dwarf galaxies contributed to the star population in our universe.
"These galaxies are forming stars so quickly they could actually double their entire mass of stars in only 150 million years -- an incredibly short astronomical timescale," adds co-author Jean-Paul Kneib, also of EPFL.
Researchers say such massive growth would take most “normal” galaxies 1 to 3 billion years.
In addition to adding new insight to how and where the stars in our universe formed, this latest finding may also help to unravel the secrets of galactic evolution. Galaxies evolve through a jumble of complex processes. As galaxies merge, they are consumed by newly-formed stars that feed on their combined gases, and exploding stars and supermassive black holes emit galactic material – a process that depletes the mass of a galaxy.
It is unusual to find a galaxy in a state of starburst, which suggests to researchers starburst galaxies are the result of an unusual incident in the past, such as a violent merger.
The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington.
For images and more information about Hubble, visit:
Ray Villard | Eurek Alert!
Spiral arms: not just in galaxies
30.09.2016 | Max-Planck-Institut für Radioastronomie
Discovery of an Extragalactic Hot Molecular Core
29.09.2016 | National Astronomical Observatory of Japan
Friction stir welding is a still-young and thus often unfamiliar pressure welding process for joining flat components and semi-finished components made of light metals.
Scientists at the University of Stuttgart have now developed two new process variants that will considerably expand the areas of application for friction stir welding.
Technologie-Lizenz-Büro (TLB) GmbH supports the University of Stuttgart in patenting and marketing its innovations.
Friction stir welding is a still-young and thus often unfamiliar pressure welding process for joining flat components and semi-finished components made of...
Optical quantum computers can revolutionize computer technology. A team of researchers led by scientists from Münster University and KIT now succeeded in putting a quantum optical experimental set-up onto a chip. In doing so, they have met one of the requirements for making it possible to use photonic circuits for optical quantum computers.
Optical quantum computers are what people are pinning their hopes on for tomorrow’s computer technology – whether for tap-proof data encryption, ultrafast...
The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.
“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...
With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.
Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...
For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.
Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...
30.09.2016 | Event News
29.09.2016 | Event News
28.09.2016 | Event News
30.09.2016 | Life Sciences
30.09.2016 | Life Sciences
30.09.2016 | Earth Sciences