Astronomers at the University of Massachusetts, Amherst report that they have observed the most luminous galaxies ever seen in the universe, objects so bright that established descriptors such as “ultra-” and “hyper-luminous” used to describe previously brightest known galaxies don’t even come close.
Stars like the Sun begin their lives as cold, dense cores of dust and gas that collapse under the influence of gravity until nuclear fusion is ignited. How the collapse process occurs is poorly understood, so astronomers are actively studying these issues by observing young stars in the process of being born.
This image from ESA’s Herschel space observatory shows the Serpens Core, the heart of a giant molecular cloud. These giant clouds are complex formations, most often made up of filaments mixed with clumpy and irregular folds, sheets and bubble-like structures. A typical spiral galaxy like the Milky Way can contain thousands of them.
The Stephan’s Quintet of galaxies in the constellation Pegasus was discovered by astronomer Édouard Stephan in 1877. This image combines observations performed at three different wavelengths, with ESA’s Herschel and XMM-Newton space observatories as well as with ground-based telescopes, to reveal the different components of the five galaxies.
In general, the larger a galaxy’s mass, the higher its rate of forming new stars. However, every now and then a galaxy will display a burst of newly-formed stars that shine brighter than the rest. Researchers using the Atacama Large Millimetre Array (ALMA) have found that galaxies forming stars at extreme rates 9 billion years ago were more efficient than average galaxies today.
A team of international scientists, led by astronomers from Cardiff University, has shown for the first time that galaxies can change their structure over the course of their lifetime. The researchers have shown that a large proportion of galaxies have undergone a major ‘metamorphosis’ since they were initially formed after the Big Bang.
Fierce flashes of light ripple through delicate tendrils of gas in this new image, from ESA’s Herschel Space Observatory, which shows the dramatic heart of a large and dense cosmic cloud known as Mon R2 in the constellation Monoceros that lies eight degrees east of the Orion Nebula. Mon R2 lies some 2700 light-years away and is studded with hot, newly-formed stars.
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