ExomatrixTV
21st December 2019, 13:31
Something In The Universe Is Killing Off Entire Galaxies:
pb-MU81GRF8
Something in the universe is killing off entire galaxies
https://thenypost.files.wordpress.com/2019/09/somethings-killing-galaxys2.jpg?quality=90&strip=all&w=618&h=410&crop=1
Galaxies are being killed off in some of the most extreme regions of the universe and scientists are trying to work out how this happens.
The cause of death is thought to be a shutdown of star formation, and a new project aims to use one of the world’s leading telescopes to observe the process in detail.
The Canadian-led project is called the Virgo Environment Traced in Carbon Monoxide survey (VERTICO).
It will investigate how galaxies can be killed off by their own environment.
Principal investigator Toby Brown explained in The Conversation (https://theconversation.com/something-is-killing-galaxies-and-scientists-are-on-the-case-123236) that he is leading a team of 30 experts who will be using the Atacama Large Millimeter Array (ALMA (https://www.almaobservatory.org/en/home/)) telescope to map stars being made in our nearest galaxy cluster, the Virgo Cluster.
The Virgo Cluster contains up to 2,000 galaxies.
The team will map molecular hydrogen gas in the galaxies because this is the fuel used to make stars.
ALMA is actually made up of 66 radio telescopes in the Chilean desert and is said to be ideal for studying clouds of dense gas that form new stars.
Galaxy environments and how they dictate the life and death of galaxies are shrouded in mystery.
However, scientists do know that galaxy clusters like the Virgo Cluster are one of the most extreme environments in the universe.
They are known for huge gravitational forces, super-high speeds and extreme temperatures.
This can make the center of some galaxies inhospitable and other galaxies that come into contact with the areas can be killed off.
The VERTICO project aims to observe how this happens.
A violent process called ram pressure stripping can remove gas from a galaxy that falls through clusters.
When all the gas for forming stars is removed a galaxy is essentially a dead object.
Some galaxy cluster environments can also stop gases cooling in a galaxy and starve it of new star formation.
The scientists taking part in the project want to piece together already known facts like this to get a clearer image of the impact of galaxy clusters and the exact processes that trigger the death of star formation and galaxy demise.
Source (https://nypost.com/2019/09/23/something-in-the-universe-is-killing-off-entire-galaxies/)
Something Is Killing the Universe's Most Extreme Galaxies
By Toby Brown - McMaster University (https://www.livescience.com/author/toby-brown)
And scientists are looking for the killer.
https://cdn.mos.cms.futurecdn.net/SVKpLFUif6i7AcqdTCN8Kh-320-80.jpg
The spiral galaxy NGC 4330 is located in the Virgo Cluster. Ram-pressure stripped hot gas is shown in red, and a blue overlay shows star-forming gas.
In the most extreme regions of the universe, galaxies are being killed. Their star formation is being shut down and astronomers want to know why.
The first ever Canadian-led large project on one of the world's leading telescopes is hoping to do just that. The new program, called the Virgo Environment Traced in Carbon Monoxide survey (VERTICO), is investigating, in brilliant detail, how galaxies are killed by their environment.
As VERTICO's principal investigator, I lead a team of 30 experts that are using the Atacama Large Millimeter Array (ALMA) (https://www.almaobservatory.org/en/home/) to map the molecular hydrogen gas, the fuel from which new stars are made (https://science.nasa.gov/astrophysics/focus-areas/how-do-stars-form-and-evolve), at high resolution across 51 galaxies in our nearest galaxy cluster, called the Virgo Cluster (https://apod.nasa.gov/apod/ap150804.html).
Commissioned in 2013 at a cost of US$1.4 billion, ALMA is an array of connected radio dishes at an altitude of 5,000 metres in the Atacama Desert of northern Chile (https://www.almaobservatory.org/en/about-alma-at-first-glance/). It is an international partnership between Europe, the United States, Canada, Japan, South Korea, Taiwan and Chile. The largest ground-based astronomical project in existence, ALMA is the most advanced millimetre wavelength telescope ever built and ideal for studying the clouds of dense cold gas from which new stars form, which cannot be seen using visible light.
Large ALMA research programs such as VERTICO are designed to address strategic scientific issues that will lead to a major advance or breakthrough in the field.
Galaxy clusters
Where galaxies live in the universe and how they interact with their surroundings (the intergalactic medium that surrounds them) and each other are major influences on their ability to form stars. But precisely how this so-called environment dictates the life and death of galaxies remains a mystery.
Galaxy clusters (https://imagine.gsfc.nasa.gov/science/objects/clusters.html) are the most massive and most extreme environments in the universe, containing many hundreds or even thousands of galaxies. Where you have mass, you also have gravity and the huge gravitational forces present in clusters accelerates galaxies to great speeds, often thousands of kilometres-per-second, and superheats the plasma in between galaxies to temperatures so high that it glows with X-ray light (http://www.mpe.mpg.de/990081/VirgoCluster).
In the dense, inhospitable interiors of these clusters, galaxies interact strongly with their surroundings and with each other. It is these interactions that can kill off — or quench — their star formation.
Understanding which quenching mechanisms shut off star formation and how they do it is the main focus of the VERTICO collaboration's research.
The life cycle of galaxies
As galaxies fall through clusters, the intergalactic plasma can rapidly remove their gas in a violent process called ram pressure stripping (https://astronomy.swin.edu.au/cosmos/R/Ram+Pressure+Stripping). When you remove the fuel for star formation, you effectively kill the galaxy, turning it into a dead object in which no new stars are formed.
In addition, the high temperature of clusters can stop hot gas cooling and condensing onto galaxies. In this case, the gas in the galaxy isn't actively removed by the environment but is consumed as it forms stars. This process leads to a slow, inexorable shut down in star formation known, somewhat morbidly, as starvation or strangulation.
While these processes vary considerably, each leaves a unique, identifiable imprint on the galaxy's star-forming gas. Piecing these imprints together to form a picture of how clusters drive changes in galaxies is a major focus of the VERTICO collaboration. Building on decades of work (https://arxiv.org/pdf/0908.3017.pdf) to provide insight into how environment drives galaxy evolution, we aim to add a critical new piece of the puzzle.
An ideal case study
The Virgo Cluster is an ideal location for such a detailed study of environment. It is our nearest massive galaxy cluster and is in the process of forming, which means that we can get a snapshot of galaxies in different stages of their life cycles. This allows us to build up a detailed picture of how star formation is shut off in cluster galaxies.
Galaxies in the Virgo cluster have been observed at almost every wavelength in the electromagnetic spectrum (for example, radio (http://www.astro.yale.edu/viva/), optical (http://cdsarc.u-strasbg.fr/viz-bin/cat/J/ApJS/215/22) and ultraviolet (http://galex.oamp.fr/guvics/) light), but observations of star-forming gas (made at at millimeter wavelengths) with the required sensitivity and resolution do not exist yet. As one of the largest galaxy surveys on ALMA to date, VERTICO will provide high resolution maps of molecular hydrogen gas — the raw fuel for star formation — for 51 galaxies.
With ALMA data for this large sample of galaxies, it will be possible to reveal exactly which quenching mechanisms, ram pressure stripping or starvation, are killing galaxies in extreme environments and how.
By mapping the star-forming gas in galaxies that are the smoking gun examples of environment-driven quenching, VERTICO will advance our current understanding of how galaxies evolve in the densest regions of the Universe.
Source (https://www.livescience.com/whats-killing-universe-extreme-galaxies.html)
IC 3418 (https://en.wikipedia.org/wiki/IC_3418)
pb-MU81GRF8
Something in the universe is killing off entire galaxies
https://thenypost.files.wordpress.com/2019/09/somethings-killing-galaxys2.jpg?quality=90&strip=all&w=618&h=410&crop=1
Galaxies are being killed off in some of the most extreme regions of the universe and scientists are trying to work out how this happens.
The cause of death is thought to be a shutdown of star formation, and a new project aims to use one of the world’s leading telescopes to observe the process in detail.
The Canadian-led project is called the Virgo Environment Traced in Carbon Monoxide survey (VERTICO).
It will investigate how galaxies can be killed off by their own environment.
Principal investigator Toby Brown explained in The Conversation (https://theconversation.com/something-is-killing-galaxies-and-scientists-are-on-the-case-123236) that he is leading a team of 30 experts who will be using the Atacama Large Millimeter Array (ALMA (https://www.almaobservatory.org/en/home/)) telescope to map stars being made in our nearest galaxy cluster, the Virgo Cluster.
The Virgo Cluster contains up to 2,000 galaxies.
The team will map molecular hydrogen gas in the galaxies because this is the fuel used to make stars.
ALMA is actually made up of 66 radio telescopes in the Chilean desert and is said to be ideal for studying clouds of dense gas that form new stars.
Galaxy environments and how they dictate the life and death of galaxies are shrouded in mystery.
However, scientists do know that galaxy clusters like the Virgo Cluster are one of the most extreme environments in the universe.
They are known for huge gravitational forces, super-high speeds and extreme temperatures.
This can make the center of some galaxies inhospitable and other galaxies that come into contact with the areas can be killed off.
The VERTICO project aims to observe how this happens.
A violent process called ram pressure stripping can remove gas from a galaxy that falls through clusters.
When all the gas for forming stars is removed a galaxy is essentially a dead object.
Some galaxy cluster environments can also stop gases cooling in a galaxy and starve it of new star formation.
The scientists taking part in the project want to piece together already known facts like this to get a clearer image of the impact of galaxy clusters and the exact processes that trigger the death of star formation and galaxy demise.
Source (https://nypost.com/2019/09/23/something-in-the-universe-is-killing-off-entire-galaxies/)
Something Is Killing the Universe's Most Extreme Galaxies
By Toby Brown - McMaster University (https://www.livescience.com/author/toby-brown)
And scientists are looking for the killer.
https://cdn.mos.cms.futurecdn.net/SVKpLFUif6i7AcqdTCN8Kh-320-80.jpg
The spiral galaxy NGC 4330 is located in the Virgo Cluster. Ram-pressure stripped hot gas is shown in red, and a blue overlay shows star-forming gas.
In the most extreme regions of the universe, galaxies are being killed. Their star formation is being shut down and astronomers want to know why.
The first ever Canadian-led large project on one of the world's leading telescopes is hoping to do just that. The new program, called the Virgo Environment Traced in Carbon Monoxide survey (VERTICO), is investigating, in brilliant detail, how galaxies are killed by their environment.
As VERTICO's principal investigator, I lead a team of 30 experts that are using the Atacama Large Millimeter Array (ALMA) (https://www.almaobservatory.org/en/home/) to map the molecular hydrogen gas, the fuel from which new stars are made (https://science.nasa.gov/astrophysics/focus-areas/how-do-stars-form-and-evolve), at high resolution across 51 galaxies in our nearest galaxy cluster, called the Virgo Cluster (https://apod.nasa.gov/apod/ap150804.html).
Commissioned in 2013 at a cost of US$1.4 billion, ALMA is an array of connected radio dishes at an altitude of 5,000 metres in the Atacama Desert of northern Chile (https://www.almaobservatory.org/en/about-alma-at-first-glance/). It is an international partnership between Europe, the United States, Canada, Japan, South Korea, Taiwan and Chile. The largest ground-based astronomical project in existence, ALMA is the most advanced millimetre wavelength telescope ever built and ideal for studying the clouds of dense cold gas from which new stars form, which cannot be seen using visible light.
Large ALMA research programs such as VERTICO are designed to address strategic scientific issues that will lead to a major advance or breakthrough in the field.
Galaxy clusters
Where galaxies live in the universe and how they interact with their surroundings (the intergalactic medium that surrounds them) and each other are major influences on their ability to form stars. But precisely how this so-called environment dictates the life and death of galaxies remains a mystery.
Galaxy clusters (https://imagine.gsfc.nasa.gov/science/objects/clusters.html) are the most massive and most extreme environments in the universe, containing many hundreds or even thousands of galaxies. Where you have mass, you also have gravity and the huge gravitational forces present in clusters accelerates galaxies to great speeds, often thousands of kilometres-per-second, and superheats the plasma in between galaxies to temperatures so high that it glows with X-ray light (http://www.mpe.mpg.de/990081/VirgoCluster).
In the dense, inhospitable interiors of these clusters, galaxies interact strongly with their surroundings and with each other. It is these interactions that can kill off — or quench — their star formation.
Understanding which quenching mechanisms shut off star formation and how they do it is the main focus of the VERTICO collaboration's research.
The life cycle of galaxies
As galaxies fall through clusters, the intergalactic plasma can rapidly remove their gas in a violent process called ram pressure stripping (https://astronomy.swin.edu.au/cosmos/R/Ram+Pressure+Stripping). When you remove the fuel for star formation, you effectively kill the galaxy, turning it into a dead object in which no new stars are formed.
In addition, the high temperature of clusters can stop hot gas cooling and condensing onto galaxies. In this case, the gas in the galaxy isn't actively removed by the environment but is consumed as it forms stars. This process leads to a slow, inexorable shut down in star formation known, somewhat morbidly, as starvation or strangulation.
While these processes vary considerably, each leaves a unique, identifiable imprint on the galaxy's star-forming gas. Piecing these imprints together to form a picture of how clusters drive changes in galaxies is a major focus of the VERTICO collaboration. Building on decades of work (https://arxiv.org/pdf/0908.3017.pdf) to provide insight into how environment drives galaxy evolution, we aim to add a critical new piece of the puzzle.
An ideal case study
The Virgo Cluster is an ideal location for such a detailed study of environment. It is our nearest massive galaxy cluster and is in the process of forming, which means that we can get a snapshot of galaxies in different stages of their life cycles. This allows us to build up a detailed picture of how star formation is shut off in cluster galaxies.
Galaxies in the Virgo cluster have been observed at almost every wavelength in the electromagnetic spectrum (for example, radio (http://www.astro.yale.edu/viva/), optical (http://cdsarc.u-strasbg.fr/viz-bin/cat/J/ApJS/215/22) and ultraviolet (http://galex.oamp.fr/guvics/) light), but observations of star-forming gas (made at at millimeter wavelengths) with the required sensitivity and resolution do not exist yet. As one of the largest galaxy surveys on ALMA to date, VERTICO will provide high resolution maps of molecular hydrogen gas — the raw fuel for star formation — for 51 galaxies.
With ALMA data for this large sample of galaxies, it will be possible to reveal exactly which quenching mechanisms, ram pressure stripping or starvation, are killing galaxies in extreme environments and how.
By mapping the star-forming gas in galaxies that are the smoking gun examples of environment-driven quenching, VERTICO will advance our current understanding of how galaxies evolve in the densest regions of the Universe.
Source (https://www.livescience.com/whats-killing-universe-extreme-galaxies.html)
IC 3418 (https://en.wikipedia.org/wiki/IC_3418)