Using the world’s largest telescopes, researchers have discovered ancient cold gas clouds larger than galaxies in the early Universe and solved a 40 year old mystery.
For decades, they have been on a mission to measure gas clouds, but failed due to unstable star formations and dim lighting.
Researchers were able to line up the gas clouds with other galaxies to measure them - and found they are larger than galaxies in the early universe.
Researchers have been on a mission to measure gas clouds, but failed due to unstable star formations and dim lighting they produced. But, with the help of the world's largest telescopes, researchers were able to line up the gas clouds with other galaxies and found they are actually larger than galaxies in the early universe
The findings were unveiled at the 227th meeting of the American Astronomical Society in Orlando, Florida by Swinburn University of Technology and St. Michael's College.
Researchers realized that finding damped Lyman alpha systems, or DLAs in the line of sight to background galaxies would enable measurements of their size by determining how much of the galaxy they cover.
'Our new method first identifies galaxies that are more likely to have intervening DLA gas clouds and then searches for them using long, deep exposures on the powerful Keck Observatory 10m telescopes in Hawaii and deep data from the VLT 8m telescopes in Chile,' said Associate Professor Jeff Cooke of Swinburn University.
'The technique is timely as the next generation of giant 30m telescopes will be online in several years and are ideal to exploit this method to routinely gather large numbers of DLAs for study.'
These type of gas clouds hold most of the universe's cold gas and it's said they can contain enough to form most of the stars, like the Milky Way.
Since DLAs star formation isn't constant, the light isn't bright enough to observe.
Researchers could only detect them once they have fallen in line of sight with a more distant bright object and leave an unmistakable absorption signature in the background object's light.
VLT 8m telescopes in Chile (pictured). Researchers realized that finding damped Lyman alpha systems, or DLAs in the line of sight to background galaxies would enable measurements of their size by determining how much of the galaxy they cover
Before this recent discovery was made, quasars were used as the background objects to search for these gas clouds.
But although quasars are extremely bright, they are also very rare and tiny, only a fraction of a light year across.
Whereas galaxies are quite common and provide a 100 million-fold increase in area to probe DLAs.
Before this recent discovery was made, quasars were used as the background objects to search for these gas clouds. But although quasars are extremely bright, they are also very rare and tiny, only a fraction of a light year across
'Using the galaxy technique, DLAs can be studied in large numbers to provide a 3-D tomographic picture of distribution of gas clouds in the early Universe and help complete our understanding of how galaxies formed and evolved over cosmic time,' says Associate Professor John O'Meara from St. Michael's College.
A series of massive 'super star' systems erupted into enormous balls of gas and dust have been discovered in neighbouring galaxies for the first time this week.
Astronomers had only seen one example of this rare eruption before, around a binary star system called Eta Carinae 7,500 light years away in our own galaxy.
Astronomers have, for the first time, identified enormous 'super stars' similar to one known as Eta Carinae outside our own galaxy for the first time. Eta Carinae (pictured) is thought to be undergoing a rare type of star evolution after the binary system erupted in the mid 19th century throwing out a huge cloud of dust and gas
This huge eruption in the mid-19th century is thought to have hurled at least 10 times the mass of our own sun into space, to create a huge cloud of gas and dust.
Eta Carinae shines five million times brighter than our own sun, making it one of the most luminous objects in the sky within 10,000 light years of Earth.
But now scientists said they have discovered five similar objects, known as Eta Twins, in galaxies beyond our own.
It could provide a rare opportunity to study these rare astronomical phenomon and learn more about how stars evolve.
Dr Rubab Khan, a researcher at Nasa's Goddard Space Flight Centre in Greenbelt, Maryland, said these 'super stars' could help to distribute the chemical elements vital to life and may be a precursor to exploding as supernovae.
Experts believe Eta Carinae may be on the verge of exploding in an enormous supernovae.
Dr Khan said: 'The most massive stars are always rare, but they have tremendous impact on the chemical and physical evolution of their host galaxy.'
The nearby spiral galaxy M83 (pictured) was found to host two potential Eta twins (inset left and right). Researchers hope studying these may help to reveal new details about this rare type of star
In total, the researchers have found five Eta twins (pictured) in four different galaxies between 15 and 26 million light years away. These rare stellar eruptions throw out huge amounts of dust and gas that form clouds in the region around the star. Some scientists believe they could be a precursor to a supernovae
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