May 20, 2014 by Lea Kivivali
(Phys.org) —An international team, led by researchers from Swinburne University of Technology, has found evidence that the Universe broke its rising 'fever' about 11 billion years ago.
They measured the temperature of the Universe when it was 3 to 4 billion years old by studying the gas in between galaxies – the intergalactic medium. During these early years of the Universe's development, many extremely active galaxies were 'switching on' for the first time and heating their surroundings.
"However, 11 billion years ago, this fever seems to have broken and the Universe began cooling down again," lead researcher Elisa Boera, a PhD student from Swinburne's Centre for Astrophysics and Supercomputing, said.
"The intergalactic medium is an excellent recorder of the Universe's history. It retains memory of the big events that affected its properties, such as temperature and composition, during its different phases of evolution."
An earlier study found that the Universe caught this fever early in its history. Its authors used a new 'thermometer' – the imprint left on the light by the intergalactic medium as it travelled to Earth from distant, extremely bright objects called quasars.
In the new study, Ms Boera collected the bluest light that Earth's atmosphere transmits – harsh ultraviolet (UV) light from 60 quasars – and used the same method as the earlier study. This UV light comes from slightly later in the Universe's development, allowing the new temperature measurement.
This video is not supported by your browser at this time.
An animation of the Universe's 'fever' breaking: As the UV light from powerful quasars ionizes the helium in the intergalactic medium, the gas heats up. But when all the helium is ionized, the quasar light can no longer heat the gas; it passes straight through and the gas begins to cool down as the Universe expands.
"The quasar light suggests that the Universe had cooled by about 1000 degrees C within 1 billion years after reaching its maximum of 13,000 degrees," Ms Boera said.
"This cooling trend has probably continued to the present day."
Why did the Universe's fever break?
"We think the answer is helium," co-author of the new study Swinburne Associate Professor Michael Murphy said.
"Fourteen per cent of the intergalactic gas is helium and, 12 billion years ago, it was absorbing the intense radiation from active galaxies, losing electrons in the process.
"The electrons whizz around, heating up the gas. It's similar to the greenhouse effect on Earth: Carbon dioxide gas absorbs infrared radiation and heats our atmosphere.
"Once all the helium was ionized, the radiation would simply pass through the gas without heating it.
"Then, as the Universe expands the gas cools down, just like the cold gas sprayed from an aerosol can – it quickly cools as it expands out of the can."
The study has been published in the Monthly Notices of the Royal Astronomical Society.
Explore further: Spectrum of gamma-ray burst's afterglow indicates beginning of re-ionization process
Apparent Magnitude
Finding the mass of a super-massive Black Hole?
Why does the furthest stars seem to be moving away faster than light?
star orbits and the Big Bang
Sagittarius A*
Sun or sol?
More from Physics Forums - Astronomy & Astrophysics
Related Stories
Spectrum of gamma-ray burst's afterglow indicates beginning of re-ionization process
Apr 30, 2014
A research team, led by Professor Tomonori Totani (School of Science, the University of Tokyo) and composed of scientists from the National Astronomical Observatory of Japan, the Tokyo Institute of Technology ...
Astronomers find evidence of cosmic climate change
Nov 02, 2010
(PhysOrg.com) -- Evidence of an intense warming period in the Universe's early history, described as a form of "cosmic climate change", has been found by an international team of astronomers.
The intergalactic medium in the young universe
Sep 30, 2013
(Phys.org) —In its earliest years, the universe was so hot that electrons and protons could not bind together in neutral atoms: all of the gas in the cosmos was ionized. Then, after 380,000 years of expansion, ...
Hubble astronomers discover early universe was overheated
Oct 07, 2010
If you think global warming is bad, 11 billion years ago the entire universe underwent, well, universal warming.
'Sideline quasars' helped to stifle early galaxy formation
Mar 21, 2013
University of Colorado Boulder astronomers targeting one of the brightest quasars glowing in the universe some 11 billion years ago say "sideline quasars" likely teamed up with it to heat abundant helium ...
CSIRO telescope takes temperature of Universe
Jan 23, 2013
(Phys.org)—Using the CSIRO Australia Telescope Compact Array near Narrabri, NSW, an international team from Sweden, France, Germany and Australia has measured how warm the Universe was when it was half ...
Recommended for you
Confirmed: Stellar behemoth self-destructs in a Type IIb supernova
1 hour ago
Our Sun may seem pretty impressive: 330,000 times as massive as Earth, it accounts for 99.86 percent of the Solar System's total mass; it generates about 400 trillion trillion watts of power per second; and ...
Very distant galaxy cluster confirmed
3 hours ago
The structures and star populations of massive galaxies appear to change as they age, but much about how these galaxies formed and evolved remains mysterious. Many of the oldest and most massive galaxies ...
Revealing the complex outflow structure of binary UY Aurigae
6 hours ago
An international team of astronomers, led by Dr. Tae-Soo Pyo (Subaru Telescope, NAOJ), has revealed a complicated outflow structure in the binary UY Aur (Aurigae). The team observed the binary using the Gemini ...
A star cluster in the wake of Carina
8 hours ago
This colorful new image from the MPG/ESO 2.2-meter telescope at ESO's La Silla Observatory in Chile shows the star cluster NGC 3590. These stars shine brightly in front of a dramatic landscape of dark patches ...
Are the BICEP2 results invalid? Probably not
May 20, 2014
Recently rumors have been flying that the BICEP2 results regarding the cosmic inflationary period may be invalid. It all started with a post by Dan Falkowski on his blog Resonaances, where he claimed that the BICEP2 had misinterpreted some data, which render ...
Astronomers identify signature of Earth-eating stars
May 20, 2014
(Phys.org) —Some Sun-like stars are 'Earth-eaters.' During their development they ingest large amounts of the rocky material from which 'terrestrial' planets like Earth, Mars and Venus are made.
User comments : 6
Adjust slider to filter visible comments by rank
Display comments: newest first
cantdrive85
1.5 / 5 (16) May 20, 2014
Nothing more than a bunch of assumptions about their theoretical mumbo jumbo...
Whydening Gyre
4.6 / 5 (10) May 20, 2014
Nothing more than a bunch of assumptions about their theoretical mumbo jumbo...
Which happens to be an assumption -on your part.
philw1776
5 / 5 (8) May 20, 2014
It is not an "assumption" when you actually measure something as they did in this and prior studies.
Mimath224
5 / 5 (2) 17 hours ago
@cantdrive85 There is only one assumption, that the laws of physics were the same then as they are now. The measurements and reasoning in the article seem to be straight forward although thete is one point that I can't quite grasp.
@Whydening Gyre, you (or someone else following this) might be able to help me. Obviously we don't know what the condition is of distant QSO's is at this moment but if they heated gases to a certain temp wouldn't they continue to do this after cooling? Indeed would there a cooling at all so that the temp would rise and fall as the cooling and re-heating took place? Is it implied that QSO's would be moving away from a gas a such a rate that re-heating couldn't happen? Perhaps I have misunderstood; has the measurements been done on successive gases cominig into contact as QSO's moved away?
vidyunmaya
1 / 5 (3) 16 hours ago
Sub:Ignorance of the Worst Kind-Science at cross-purpose
Deliberate mis-lead and ignorance of the Worst kind-to save Big-Bang fever .How long this mischief can go without searching origins ? This mode self-defeats the purpose of Scientific Research. Need to search Cause and effect
swordsman
not rated yet 5 hours ago
Neat theory! Could possibly be simulated on a small scale.
- Physics
- Nanotechnology
- Earth
- Astronomy & Space
- Chemistry
- Biology
- Technology
- Other Sciences
- Medicine & Health
© Phys.org™ 2003-2013, Science X network
May 20, 2014 by Lea Kivivali
(Phys.org) —An international team, led by researchers from Swinburne University of Technology, has found evidence that the Universe broke its rising 'fever' about 11 billion years ago.
They measured the temperature of the Universe when it was 3 to 4 billion years old by studying the gas in between galaxies – the intergalactic medium. During these early years of the Universe's development, many extremely active galaxies were 'switching on' for the first time and heating their surroundings.
"However, 11 billion years ago, this fever seems to have broken and the Universe began cooling down again," lead researcher Elisa Boera, a PhD student from Swinburne's Centre for Astrophysics and Supercomputing, said.
"The intergalactic medium is an excellent recorder of the Universe's history. It retains memory of the big events that affected its properties, such as temperature and composition, during its different phases of evolution."
An earlier study found that the Universe caught this fever early in its history. Its authors used a new 'thermometer' – the imprint left on the light by the intergalactic medium as it travelled to Earth from distant, extremely bright objects called quasars.
In the new study, Ms Boera collected the bluest light that Earth's atmosphere transmits – harsh ultraviolet (UV) light from 60 quasars – and used the same method as the earlier study. This UV light comes from slightly later in the Universe's development, allowing the new temperature measurement.
This video is not supported by your browser at this time.
An animation of the Universe's 'fever' breaking: As the UV light from powerful quasars ionizes the helium in the intergalactic medium, the gas heats up. But when all the helium is ionized, the quasar light can no longer heat the gas; it passes straight through and the gas begins to cool down as the Universe expands.
"The quasar light suggests that the Universe had cooled by about 1000 degrees C within 1 billion years after reaching its maximum of 13,000 degrees," Ms Boera said.
"This cooling trend has probably continued to the present day."
Why did the Universe's fever break?
"We think the answer is helium," co-author of the new study Swinburne Associate Professor Michael Murphy said.
"Fourteen per cent of the intergalactic gas is helium and, 12 billion years ago, it was absorbing the intense radiation from active galaxies, losing electrons in the process.
"The electrons whizz around, heating up the gas. It's similar to the greenhouse effect on Earth: Carbon dioxide gas absorbs infrared radiation and heats our atmosphere.
"Once all the helium was ionized, the radiation would simply pass through the gas without heating it.
"Then, as the Universe expands the gas cools down, just like the cold gas sprayed from an aerosol can – it quickly cools as it expands out of the can."
The study has been published in the Monthly Notices of the Royal Astronomical Society.
Explore further: Spectrum of gamma-ray burst's afterglow indicates beginning of re-ionization process
Apparent Magnitude
Finding the mass of a super-massive Black Hole?
Why does the furthest stars seem to be moving away faster than light?
star orbits and the Big Bang
Sagittarius A*
Sun or sol?
More from Physics Forums - Astronomy & Astrophysics
Related Stories
Spectrum of gamma-ray burst's afterglow indicates beginning of re-ionization process
Apr 30, 2014
A research team, led by Professor Tomonori Totani (School of Science, the University of Tokyo) and composed of scientists from the National Astronomical Observatory of Japan, the Tokyo Institute of Technology ...
Astronomers find evidence of cosmic climate change
Nov 02, 2010
(PhysOrg.com) -- Evidence of an intense warming period in the Universe's early history, described as a form of "cosmic climate change", has been found by an international team of astronomers.
The intergalactic medium in the young universe
Sep 30, 2013
(Phys.org) —In its earliest years, the universe was so hot that electrons and protons could not bind together in neutral atoms: all of the gas in the cosmos was ionized. Then, after 380,000 years of expansion, ...
Hubble astronomers discover early universe was overheated
Oct 07, 2010
If you think global warming is bad, 11 billion years ago the entire universe underwent, well, universal warming.
'Sideline quasars' helped to stifle early galaxy formation
Mar 21, 2013
University of Colorado Boulder astronomers targeting one of the brightest quasars glowing in the universe some 11 billion years ago say "sideline quasars" likely teamed up with it to heat abundant helium ...
CSIRO telescope takes temperature of Universe
Jan 23, 2013
(Phys.org)—Using the CSIRO Australia Telescope Compact Array near Narrabri, NSW, an international team from Sweden, France, Germany and Australia has measured how warm the Universe was when it was half ...
Recommended for you
Confirmed: Stellar behemoth self-destructs in a Type IIb supernova
1 hour ago
Our Sun may seem pretty impressive: 330,000 times as massive as Earth, it accounts for 99.86 percent of the Solar System's total mass; it generates about 400 trillion trillion watts of power per second; and ...
Very distant galaxy cluster confirmed
3 hours ago
The structures and star populations of massive galaxies appear to change as they age, but much about how these galaxies formed and evolved remains mysterious. Many of the oldest and most massive galaxies ...
Revealing the complex outflow structure of binary UY Aurigae
6 hours ago
An international team of astronomers, led by Dr. Tae-Soo Pyo (Subaru Telescope, NAOJ), has revealed a complicated outflow structure in the binary UY Aur (Aurigae). The team observed the binary using the Gemini ...
A star cluster in the wake of Carina
8 hours ago
This colorful new image from the MPG/ESO 2.2-meter telescope at ESO's La Silla Observatory in Chile shows the star cluster NGC 3590. These stars shine brightly in front of a dramatic landscape of dark patches ...
Are the BICEP2 results invalid? Probably not
May 20, 2014
Recently rumors have been flying that the BICEP2 results regarding the cosmic inflationary period may be invalid. It all started with a post by Dan Falkowski on his blog Resonaances, where he claimed that the BICEP2 had misinterpreted some data, which render ...
Astronomers identify signature of Earth-eating stars
May 20, 2014
(Phys.org) —Some Sun-like stars are 'Earth-eaters.' During their development they ingest large amounts of the rocky material from which 'terrestrial' planets like Earth, Mars and Venus are made.
User comments : 6
Adjust slider to filter visible comments by rank
Display comments: newest first
cantdrive85
1.5 / 5 (16) May 20, 2014
Nothing more than a bunch of assumptions about their theoretical mumbo jumbo...
Whydening Gyre
4.6 / 5 (10) May 20, 2014
Nothing more than a bunch of assumptions about their theoretical mumbo jumbo...
Which happens to be an assumption -on your part.
philw1776
5 / 5 (8) May 20, 2014
It is not an "assumption" when you actually measure something as they did in this and prior studies.
Mimath224
5 / 5 (2) 17 hours ago
@cantdrive85 There is only one assumption, that the laws of physics were the same then as they are now. The measurements and reasoning in the article seem to be straight forward although thete is one point that I can't quite grasp.
@Whydening Gyre, you (or someone else following this) might be able to help me. Obviously we don't know what the condition is of distant QSO's is at this moment but if they heated gases to a certain temp wouldn't they continue to do this after cooling? Indeed would there a cooling at all so that the temp would rise and fall as the cooling and re-heating took place? Is it implied that QSO's would be moving away from a gas a such a rate that re-heating couldn't happen? Perhaps I have misunderstood; has the measurements been done on successive gases cominig into contact as QSO's moved away?
vidyunmaya
1 / 5 (3) 16 hours ago
Sub:Ignorance of the Worst Kind-Science at cross-purpose
Deliberate mis-lead and ignorance of the Worst kind-to save Big-Bang fever .How long this mischief can go without searching origins ? This mode self-defeats the purpose of Scientific Research. Need to search Cause and effect
swordsman
not rated yet 5 hours ago
Neat theory! Could possibly be simulated on a small scale.
- Physics
- Nanotechnology
- Earth
- Astronomy & Space
- Chemistry
- Biology
- Technology
- Other Sciences
- Medicine & Health
© Phys.org™ 2003-2013, Science X network
via Science - Google News http://ift.tt/1tlemJ4
Put the internet to work for you.
No comments:
Post a Comment