This is about 400 million light-years away from the most distant clusters known so far * The fact that the cluster contains mature galaxies means that these galaxies were formed near the beginning of the universe
An international team of astronomers from the Max Planck Institute for the Physics of the Extraterrestrial Universe, the University of Tokyo and Kyoto University discovered the cluster using the Subaru Ground Telescope in Hawaii and the Newton Space Telescope to observe the cluster at different wavelengths.
Using the Multi-Object Infrared Camera and Spectrometer (MOIRCS) on the Subaru Telescope, the team was able to look at wavelengths in the near-infrared region, where galaxies are brightest.
"The MOIRCS instrument has a very strong capability of measuring the distances to the galaxies. This is what made our challenging observation possible," said Masayuki Tanaka from the University of Tokyo. "Although we were able to prove the existence of only a few massive galaxies from this distance, there is convincing evidence that the cluster is real, and connected by gravity.."
Like a contour map, the arrows in the image indicate that the galaxies are located at the same distance, and focus into a cluster around the center of the image. The "height lines" indicate X-ray emission from the cluster. The galaxies confirmed to be 9.6 billion light years away are circled. The combination of X-ray detection and the collection of massive galaxies proves that this is a cluster held together by gravity."
The confirmation that the individual galaxies are indeed bound together by gravity was obtained from observations in completely different wavelength ranges. The material between the galaxies in the cluster heats up to extreme temperatures and emits light at wavelengths shorter than those of visible light. So the team used the XMM-Niton space telescope to look for this X-ray radiation.
"Despite the difficulties in collecting photons in the X-ray region with a small, efficient telescope about the size of a backyard telescope (meaning Newton), we observed a clear signature of hot gas in the cluster," said Alexis Pinhagenov of the Max Planck Institute for Extraterrestrial Physics.
"The combination of these pioneering observations at different wavelengths led to the discovery of the galaxy cluster 9.6 billion light-years away - about 400 million light-years further back in time than the most distant known cluster to date.
The analysis of the data collected on the individual galaxies shows that the cluster already contains plenty of mature massive galaxies that were formed about 2 billion years earlier. Since the aging process of galaxies is slow, the presence of these galaxies requires that the cluster formed through mergers of large groups of galaxies, each of which is dominated by a dominant galaxy. The cluster is therefore an ideal laboratory for studying the evolution of galaxies, when the universe was only about a third of its current age.
Because distant galaxy clusters are important for tracking large-scale structures and primordial density variations in the universe, future similar observations could provide additional important information for cosmologists. The result achieved so far shows that the facilities in the near-infrared range are able to provide accurate analyzes of distant galaxy populations and that the combination with data in the X-range is a new and powerful tool. Therefore, the team members will continue to search for more distant galaxy clusters.
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An important addition
The truth is that it even occurred to me to mention something about it and I don't know why I didn't.
Note that, on the other hand, it will be difficult to cool down in space because most of our cooling in the air is based on cooling by heat conduction and not by radiation - this, by the way, is a big problem in the design of objects that have to stay in space.
A. Ben Ner, Zvi:
I thought there was room for further clarification of something that seems to me to be at the root of A. Ben Ner's question.
I hope I am not wrong in describing the situation.
After all, it is known that interstellar space and certainly intergalactic space is very cold and not hot.
What bothers A. Ben Ner is, in my opinion, the apparent contradiction between the temperature of the gas and what is known as the temperature that actually prevails there.
He may also be troubled by the question of how it is that such hot interstellar gas does not heat, for example, the Earth.
The answer is that there is something misleading in people's everyday understanding of the concept of the temperature of a gas (or of a collection of particles).
The temperature of a gas is basically the average kinetic energy of the particles that make it up.
This temperature does not necessarily betray its ability to "heat things" and this is because the "ability to heat" is also a function of the amount of particles and not only of their speed.
In other words - the interstellar gas can cause the development of cancer in a person exposed to it - but not a feeling of heat.
The lack of connection between the temperature and the number of molecules is easy to understand from the kinetic theory of gases
http://en.wikipedia.org/wiki/Kinetic_theory
But it is also revealed in the simple and familiar relationship between the pressure and temperature of an ideal gas
http://en.wikipedia.org/wiki/Ideal_gas_law
Note, a. Ben Ner, that in the above formula there is N only on the side of T.
This fact indicates that the concept of pressure includes the number of molecules, while the concept of temperature does not include this number, therefore this factor must be added to the side of the equation where T appears.
Thanks to Michael for the link
So in order to refine:
Interstellar matter, including intergalactic matter, is at a temperature of millions of degrees (between 5^10 and 7^10 as mentioned in the link) and this is for the reasons stated in (2) - in the heat it is not in an atomic or molecular state but exists as plasma. The photons that characterize this medium are a black body spectrum at a temperature of about 3 degrees Kelvin that originates from the cosmic background radiation. The universe is not in thermal equilibrium (I will explain the concept at the end of the correspondence) because it is very difficult for atomic matter to cool.
Thermal equilibrium is a requirement for a system in a stable state (if the universe is not in this state, then the times to reach the stable state are much longer than the age of the universe - or the characteristic time scales for its change) - in general, what it says is that when a hot body interacts with a cold body - the temperature will equalize
A. Ben Ner, Zvi:
Although it is also mentioned there, here is a section that discusses the subject directly
http://en.wikipedia.org/wiki/Intergalactic_medium#Intergalactic
I went through the article you mentioned on the wiki, unfortunately only skimming due to time pressure now. it seems
to me because the article there focuses on the galactic interior material:
"...the interstellar medium (or ISM) is the gas and dust that pervade interstellar space: the matter that exists between the star systems within a galaxy. It fills
While the article here (and the responses so far) refer to the material in the midst of the galaxies that make up the cluster.
A. Ben Ner and Zvi:
http://en.wikipedia.org/wiki/Interstellar_medium
1. As for the dark matter, note that it is a substance that does not react to the electromagnetic force - therefore it neither radiates nor heats up as a result of radiation - therefore the discussion of it is not relevant now.
2. The temperature of 3 degrees Kelvin is the temperature of the cosmic background radiation. As far as I know this is not the temperature of the interstellar matter inside the galaxy which (along with the stars) is the bulk of the matter in the universe (baryonic matter). I know that most of the matter in the universe is in a state of plasma, so it is strange to me that it should be at a temperature of 3 degrees - also note that in order for matter to be at this low temperature, it must not absorb anything except the cosmic background radiation and this seems strange to me (because it will always absorb the light of stars).
In short - I do not know how to confirm or deny your words in full - I have no doubt that there are parts of them that are correct, but I am not sure that they are completely correct. If anyone knows more, I would also like to know.
deer
A]. Your answer is indeed very surprising.
I understand that the high temperature of the medium between the galaxies in the cluster is caused by the matter
The molecular found in it is probably mainly hydrogen atoms.
B]. About 3 months ago, I heard the lecture of Priuel Refali, at the Haste Club of the UNTA.
This lecture also dealt with galaxy clusters. The summary of that lecture is as follows:
1. About 80% of the baryonic matter of the cluster is "dark" matter among the luminous galaxies.
2. The average temperature of matter in the intergalactic medium is about 3 degrees Kelvin!!!
3. The intergalactic matter interacts with the cosmic background radiation. The emitted radiation
As a result of this interaction, it is at a temperature of about 2,7 degrees Kelvin. actually using
This radiation is measured by weighing the intergalactic mass of the cluster.
third]. The question arises, what then is the difference between the "cold" clusters and the "warm" ones.
Is it a matter of the age of the group? And maybe other additional factors?
I wonder how they look today after 9.6 billion years
A. Ben Ner,
The wording is really ambiguous, as far as I understand these are two completely different sentences and the idea is this:
1. The galaxies are bound by gravity - this is usually known based on knowing the distances between them and their speeds:
Knowing the distance comes from the fact that if you know the distance from them to you - usually based on redshift - and the angular distance between them, there is no problem knowing the distances between them. Knowing their speeds is usually done based on the Doppler effect.
Using these two data (distance and speed) you can calculate whether the total gravitational energy is positive or negative - if it is negative then they are gravitationally connected (this is the definition).
2. For the purpose of all these measurements (Doppler, angular size, etc.) they had to use radiation sensors in the x-range because the light is mostly emitted from very hot gas (gas at a temperature of millions of degrees Kelvin emits in the x-ray range).
The answer to your question, how does the gas heat up to such high temperatures, is a bit complicated -
In general, large blocks of matter cool relatively easily by emitting radiation - small blocks of matter, on the other hand, find it difficult to do so (in a very rough statement it can be said that a block of matter has difficulty emitting light at wavelengths smaller than its own size) - this makes it harder for dust to cool, and therefore Its equilibrium point is determined at a higher temp.
In the case of matter in the interstellar medium, it is usually a real molecular matter and its characteristic temperature is therefore millions of degrees. Incidentally, this is the temperature of the sun's halo in our solar system for the exact same reason (and thus it turns out that the gas in the sun's halo is three orders of magnitude hotter than on the surface of the sun).
Can someone explain the sentence:
"...the confirmation that the individual galaxies are indeed bound together by gravity was obtained from observations in completely different wavelength ranges. The material between the galaxies in the cluster heats up to extreme temperatures and emits light at wavelengths shorter than those of visible light. So the team used the XMM-Niton space telescope to search for this radiation in the X-range…”
A]. What causes the intergalactic matter to heat up to extreme temperatures?
B]. Why does this indicate a connection of the galaxies through gravity?