El Sidd
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Latest Discoveries and Images From Outer Space
- Thread starter KapitaanAli
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Verve
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Bus Yaad ai c
KapitaanAli
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May 28, 2018
AstroSat Picture of the Month (May 2018)
X-raying the celestial lighthouse in the Crab
This month's APOM is a bit different from the rest. Instead of ultraviolet images from UVIT, we bring you an exciting plot from the X-ray telescope, Cadmium-Zinc-Telluride Imager (CZTI), onboard the AstroSat. This new result, covered by the press last year, announced the discovery of X-ray polarisation from the Crab Nebula that seemed to vary in an unexpected way over the period of the pulsar within. This discovery also heralded the beginning of the field of X-ray polarisation in astronomy. Let us look at what this means.
The Crab Nebula which is about 6500 light years away in the constellation Taurus, is a result of a supernova explosion of a massive star, that was seen in 1054 AD. Powering this supernova remnant is a very strange object, known as the Crab Pulsar. The end products of massive stars are neutron stars, which weigh as much as the Sun but are only as big as a city. These rapidly spinning objects are made of exotic matter and have very strong magnetic fields. Under the right circumstances, we see them as a pulsar, which resembles a celestial lighthouse whose beam sweeps past the Earth once every pulsar rotation. Our Crab Pulsar rotates as fast as 30 times a second, and its lighthouse-like pulses have been studied extensively all the way from radio to X-rays.
Credit: Cadmium-Zinc-Telluride Imager (CZTI) team
The left panel shows the new result. One rotation period, of 33 milliseconds, is represented as the phase going from 0.0 to 1.0 and is repeated once more, from 1.0 to 2.0, for clarity. The grey line is the X-ray brightness of the Crab lighthouse, observed by CZTI. The data in colour, obtained by aggregating a large number of measurements, shows what fraction of the X-ray light is polarised, i.e., can be given a specific direction. It can be seen that when the X-ray emission (grey line) is low, the polarisation fraction is high, which is unexpected. The right panel is an artist's impression of how the supernova explosion would have looked like, in the past (credit: ESA/Hubble).
We usually describe light, which is electromagnetic radiation, by its strength and its frequency (or wavelength). In addition, we can also measure the direction in which the electric and magnetic fields of the light wave oscillates. This feature, called polarisation, is even used to make some kinds of 3-D glasses and anti-glare sunglasses. Light from celestial sources too shows polarisation but measuring this in the X-rays in incredibly difficult. So difficult, in fact, that this was seen in 1975 from the same Crab Nebula, but not from any other source since then. What Santosh Vadawale and his collaborators have done, is to use a clever trick that has been talked about for a while, and apply it to the Cadmium-Zinc-Telluride Imager (CZTI) on AstroSat which is an X-ray telescope. They perfected this technique and were able to measure X-ray polarisation accurately from the Crab Nebula. In fact, they even managed to measure it fast enough to derive how this polarisation changed during one full rotation of the Crab Pulsar, which is 33 milliseconds long. The result, which is our APOM, surprised everybody. For one, they found that the amount of polarisation was higher than expected. Second, it was high during those times when the pulsar lighthouse was pointing away from us! Astronomers are now revisiting their theories of pulsar emission to understand this. In any case, AstroSat has now opened up this new and exciting field of X-ray polsarisation. Who knows what they will discover next!
AstroSat Picture of the Month (May 2018)
X-raying the celestial lighthouse in the Crab
This month's APOM is a bit different from the rest. Instead of ultraviolet images from UVIT, we bring you an exciting plot from the X-ray telescope, Cadmium-Zinc-Telluride Imager (CZTI), onboard the AstroSat. This new result, covered by the press last year, announced the discovery of X-ray polarisation from the Crab Nebula that seemed to vary in an unexpected way over the period of the pulsar within. This discovery also heralded the beginning of the field of X-ray polarisation in astronomy. Let us look at what this means.
The Crab Nebula which is about 6500 light years away in the constellation Taurus, is a result of a supernova explosion of a massive star, that was seen in 1054 AD. Powering this supernova remnant is a very strange object, known as the Crab Pulsar. The end products of massive stars are neutron stars, which weigh as much as the Sun but are only as big as a city. These rapidly spinning objects are made of exotic matter and have very strong magnetic fields. Under the right circumstances, we see them as a pulsar, which resembles a celestial lighthouse whose beam sweeps past the Earth once every pulsar rotation. Our Crab Pulsar rotates as fast as 30 times a second, and its lighthouse-like pulses have been studied extensively all the way from radio to X-rays.
Credit: Cadmium-Zinc-Telluride Imager (CZTI) team
The left panel shows the new result. One rotation period, of 33 milliseconds, is represented as the phase going from 0.0 to 1.0 and is repeated once more, from 1.0 to 2.0, for clarity. The grey line is the X-ray brightness of the Crab lighthouse, observed by CZTI. The data in colour, obtained by aggregating a large number of measurements, shows what fraction of the X-ray light is polarised, i.e., can be given a specific direction. It can be seen that when the X-ray emission (grey line) is low, the polarisation fraction is high, which is unexpected. The right panel is an artist's impression of how the supernova explosion would have looked like, in the past (credit: ESA/Hubble).
We usually describe light, which is electromagnetic radiation, by its strength and its frequency (or wavelength). In addition, we can also measure the direction in which the electric and magnetic fields of the light wave oscillates. This feature, called polarisation, is even used to make some kinds of 3-D glasses and anti-glare sunglasses. Light from celestial sources too shows polarisation but measuring this in the X-rays in incredibly difficult. So difficult, in fact, that this was seen in 1975 from the same Crab Nebula, but not from any other source since then. What Santosh Vadawale and his collaborators have done, is to use a clever trick that has been talked about for a while, and apply it to the Cadmium-Zinc-Telluride Imager (CZTI) on AstroSat which is an X-ray telescope. They perfected this technique and were able to measure X-ray polarisation accurately from the Crab Nebula. In fact, they even managed to measure it fast enough to derive how this polarisation changed during one full rotation of the Crab Pulsar, which is 33 milliseconds long. The result, which is our APOM, surprised everybody. For one, they found that the amount of polarisation was higher than expected. Second, it was high during those times when the pulsar lighthouse was pointing away from us! Astronomers are now revisiting their theories of pulsar emission to understand this. In any case, AstroSat has now opened up this new and exciting field of X-ray polsarisation. Who knows what they will discover next!
Hamartia Antidote
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Even the Chinese reluctantly admitted they see the Apollo sites:
http://english.cas.cn/newsroom/china_research/201202/t20120207_81106.shtml
China Publishes High-resolution Full Moon Map
"...The scientists also spotted traces of the previous Apollo mission in the images, said Yan Jun, chief application scientist for China's lunar exploration project..."
Last edited:
Malik Alashter
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Lol we're in the 21st century and some people still think the same way people in the medieval ages.
I can't believe someone believe that NASA would lie to the world about earth and space objects just embarrass them selves
Verve
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And it is not hard to believe that masses are fooled and blindly believe whatever they are spoon fed!
KapitaanAli
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Discovery of a Sub-Saturn Exoplanet around a Sun-like star
The scientific team, led by Prof Abhijit Chakraborty of Physical Research Laboratory (PRL), Ahmedabad, have found a sub-Saturn or super-Neptune size planet (mass of about 27 Earth Mass and size of 6 Earth Radii) around a Sun-like star. The planet goes around the star in about 19.5days. The host star itself is about 600 light years away from the Earth. The discovery was made by measuring the mass of the planet using the indigenously designed “PRL Advance Radial-velocity Abu-sky Search” (PARAS) spectrograph integrated with 1.2m Telescope at PRL’s Gurushikhar Observatory in Mount Abu, India. This is the first of its kind spectrograph in the country, which can measure the mass of a planet going around a star and with this discovery India has joined a handful ofcountries, which have discovered planets around stars. Very few such spectrographs exist around the world (mostly in the USA and in the Europe) that can do such precise measurements. The surface temperature of the planet is around 600°C as it is very close to the host star (7 times nearer than Earth-Sun distance). This might make it unhabitable, but such a discovery is of importance for understanding the formation mechanism of such super-Neptuneor sub-Saturn kind of planets, that are too close to the host star.
The name of the host star is EPIC 211945201 or K2-236. Hence the planet will be known as EPIC 211945201b or K2-236b. Initially, the source was found to be a planetary candidate from NASA K2 (Kepler2) photometry because it was transiting, that is the planet body comes in between the star and the observer on Earth as it goes around the star and therefore it blocks a tiny amount of star-light. By measuring the amount of light blocked by the planet body, we can measure the diameter or size of the planet. It was found to be 6 Earth radii. However, The K2 photometric data combined with false positive probability calculations was not sufficient to confirm the planetary nature of the system. Therefore, an independent measurement of the mass of the body was necessary for the discovery, which was made by the PARAS spectrograph.
The gravitational pull caused by a planet on its host star makes it wobble around their common center of mass, which shifts the spectra and can be measured in terms of Radial Velocity using precise and stabilised High Resolution Spectrographs, like the PARAS. The PRL scientists observed the target over a time-baseline of 420 days (in about 1.5 years) using the PARAS spectrograph for probing the nature of the system. By measuring the amplitude of the wobbling of the host star, the mass of the planet was found to be 27±14MEarth.
Based on the mass and radius, model-dependent calculations suggest that the heavy elements, like ice, silicates, and iron content is 60-70 % of the total mass. This detection is important as it adds to a sparse catalog of confirmed exoplanets with masses between 10-70 MEarth and radii between 4-8 REarth, whose masses and radii are measured to a precision of 50% or better. Only 23 such systems (including the present) are known to this date with such precise measurement of mass and radii.
Figure Caption:Radial Velocity (RV) data points of K2-236, observed by PARAS with 1.2m telescope of PRL at Mt. Abu. Black solid curve represents the modeled RV curve. The model shows the wobbling of the host star and its amplitude gives us the mass of the exoplanet K2-236b.
The research work will appear in the June issue of the Astronomical Journal owned by the American Astronomical Society and published by IOP Publishing (the DOI of the article is 10.3847/1538-3881/aac436).
The scientific team, led by Prof Abhijit Chakraborty of Physical Research Laboratory (PRL), Ahmedabad, have found a sub-Saturn or super-Neptune size planet (mass of about 27 Earth Mass and size of 6 Earth Radii) around a Sun-like star. The planet goes around the star in about 19.5days. The host star itself is about 600 light years away from the Earth. The discovery was made by measuring the mass of the planet using the indigenously designed “PRL Advance Radial-velocity Abu-sky Search” (PARAS) spectrograph integrated with 1.2m Telescope at PRL’s Gurushikhar Observatory in Mount Abu, India. This is the first of its kind spectrograph in the country, which can measure the mass of a planet going around a star and with this discovery India has joined a handful ofcountries, which have discovered planets around stars. Very few such spectrographs exist around the world (mostly in the USA and in the Europe) that can do such precise measurements. The surface temperature of the planet is around 600°C as it is very close to the host star (7 times nearer than Earth-Sun distance). This might make it unhabitable, but such a discovery is of importance for understanding the formation mechanism of such super-Neptuneor sub-Saturn kind of planets, that are too close to the host star.
The name of the host star is EPIC 211945201 or K2-236. Hence the planet will be known as EPIC 211945201b or K2-236b. Initially, the source was found to be a planetary candidate from NASA K2 (Kepler2) photometry because it was transiting, that is the planet body comes in between the star and the observer on Earth as it goes around the star and therefore it blocks a tiny amount of star-light. By measuring the amount of light blocked by the planet body, we can measure the diameter or size of the planet. It was found to be 6 Earth radii. However, The K2 photometric data combined with false positive probability calculations was not sufficient to confirm the planetary nature of the system. Therefore, an independent measurement of the mass of the body was necessary for the discovery, which was made by the PARAS spectrograph.
The gravitational pull caused by a planet on its host star makes it wobble around their common center of mass, which shifts the spectra and can be measured in terms of Radial Velocity using precise and stabilised High Resolution Spectrographs, like the PARAS. The PRL scientists observed the target over a time-baseline of 420 days (in about 1.5 years) using the PARAS spectrograph for probing the nature of the system. By measuring the amplitude of the wobbling of the host star, the mass of the planet was found to be 27±14MEarth.
Based on the mass and radius, model-dependent calculations suggest that the heavy elements, like ice, silicates, and iron content is 60-70 % of the total mass. This detection is important as it adds to a sparse catalog of confirmed exoplanets with masses between 10-70 MEarth and radii between 4-8 REarth, whose masses and radii are measured to a precision of 50% or better. Only 23 such systems (including the present) are known to this date with such precise measurement of mass and radii.
Figure Caption:Radial Velocity (RV) data points of K2-236, observed by PARAS with 1.2m telescope of PRL at Mt. Abu. Black solid curve represents the modeled RV curve. The model shows the wobbling of the host star and its amplitude gives us the mass of the exoplanet K2-236b.
The research work will appear in the June issue of the Astronomical Journal owned by the American Astronomical Society and published by IOP Publishing (the DOI of the article is 10.3847/1538-3881/aac436).
KapitaanAli
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Jul 02, 2018
AstroSat Picture of the Month (June 2018)
Entire clusters of galaxies merging together – an ultraviolet view
Previously, we had brought you AstroSat images of individual galaxies, two galaxies merging with each other, and even a lone galaxy falling into a cluster of other galaxies. This month, we give you Abell 2256, an extremely well studied and special galaxy cluster. Abell 2256 is actually made of three separate clusters of galaxies that are all merging with each other, and will form a single massive cluster in the future. This object is at a distance of more than 800 million light years from us, and is the most distant APOM so far. The three merging clusters in Abell 2256 contains more than 500 galaxies, and the cluster is almost 100 times larger and more than 1500 times as massive as our own galaxy! This merger has produced a rich diversity of structures that have been imaged in radio wavelengths by every radio telescope in the world.
This cluster contains galaxies spread over a large area, and we have zoomed in on six of these galaxies to show you their ultraviolet images. The brightest objects in the full image are actually foreground stars in our galaxy which happen to lie in the same direction as Abell 2256.
Credits: UVIT team/ISRO/CSA.
We know that galaxy clusters are places where many spiral galaxies transform slowly into lenticular and elliptical galaxies. Spiral galaxies, like our own Milky Way, are bluer in colour and are forming stars constantly. Elliptical and lenticular galaxies however, are redder and have mainly old stars in them. Abell 2256 is one such galaxy cluster where we believe many galaxies are going through this metamorphosis. Astronomers stared at Abell 2256 for 5 hours using the UVIT on board AstroSat to image these star forming spiral galaxies, using the ultraviolet light emitted by their hot young stars. The fine detail with which the entire galaxy cluster could be imaged out to its edges by UVIT is keeping astronomers busy over the last few months. They are investigating the nature of individual galaxies in Abell 2256. They also hope to understand how these galaxies will transform into lenticular and elliptical galaxies in the future.
AstroSat Picture of the Month (June 2018)
Entire clusters of galaxies merging together – an ultraviolet view
Previously, we had brought you AstroSat images of individual galaxies, two galaxies merging with each other, and even a lone galaxy falling into a cluster of other galaxies. This month, we give you Abell 2256, an extremely well studied and special galaxy cluster. Abell 2256 is actually made of three separate clusters of galaxies that are all merging with each other, and will form a single massive cluster in the future. This object is at a distance of more than 800 million light years from us, and is the most distant APOM so far. The three merging clusters in Abell 2256 contains more than 500 galaxies, and the cluster is almost 100 times larger and more than 1500 times as massive as our own galaxy! This merger has produced a rich diversity of structures that have been imaged in radio wavelengths by every radio telescope in the world.
This cluster contains galaxies spread over a large area, and we have zoomed in on six of these galaxies to show you their ultraviolet images. The brightest objects in the full image are actually foreground stars in our galaxy which happen to lie in the same direction as Abell 2256.
Credits: UVIT team/ISRO/CSA.
We know that galaxy clusters are places where many spiral galaxies transform slowly into lenticular and elliptical galaxies. Spiral galaxies, like our own Milky Way, are bluer in colour and are forming stars constantly. Elliptical and lenticular galaxies however, are redder and have mainly old stars in them. Abell 2256 is one such galaxy cluster where we believe many galaxies are going through this metamorphosis. Astronomers stared at Abell 2256 for 5 hours using the UVIT on board AstroSat to image these star forming spiral galaxies, using the ultraviolet light emitted by their hot young stars. The fine detail with which the entire galaxy cluster could be imaged out to its edges by UVIT is keeping astronomers busy over the last few months. They are investigating the nature of individual galaxies in Abell 2256. They also hope to understand how these galaxies will transform into lenticular and elliptical galaxies in the future.
KapitaanAli
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Jul 30, 2018
ASTROSAT PICTURE OF THE MONTH (APOM) – JULY 2018
Seeing a galaxy in ‘colour’
We have met NGC 7252 before, where we had shown you an ultraviolet image of the loops and tails of gas and dust ripped apart from two galaxies as they merged to form NGC 7252. This month, we zoom in to look at the central part of the merging galaxy itself, but in colour!
UVIT onboard ASTROSAT imaged this galaxy in the Near UV (around 242 nanometres) and the Far UV (around 148 nanometres). When we divide these two images pixel by pixel, we get an 'ultraviolet colour' image. Imagine a light bulb emitting all visible colours. We will perceive it as a particular colour depending on the fraction of red versus green versus blue light it emits. Similarly, dividing the FUV and the NUV images will tell us what the 'ultraviolet colour' of NGC 7252 is, and how this colour varies across the galaxy. These 'ultraviolet colours' are represented as red to blue in the image here.
FUV − NUV colour map of NGC7252
In the figure, we see a central 'red' region surrounded by a 'blue' ring, with an outer 'red' region. The size of the image is marked in arcseconds (3600 arcseconds make a degree) and equivalently in kpc (1 kpc is 3260 light years). Koshy and his collaborators have modelled this colour to calculate the corresponding ages of the stars that emit in these regions. They have shown that there is a bunch of stars right in the middle, which are around 320 million years old. The surrounding blue ring has stars that are around 250 million years old. The even bluer clumps within the ring are only about 150 million years old. The surrounding larger region of red has stars that are more than 400 million years old.
Remember, NGC 7252 is born out of two galaxies merging together. This merger is a violent event whose effects on the gas in these galaxies is complex. The authors of this study explain how this merger would naturally lead to this scenario where different parts of the galaxy hosts stars of different ages. These have been discussed in detail in https://arxiv.org/pdf/1805.03543.pdf.
ASTROSAT PICTURE OF THE MONTH (APOM) – JULY 2018
Seeing a galaxy in ‘colour’
We have met NGC 7252 before, where we had shown you an ultraviolet image of the loops and tails of gas and dust ripped apart from two galaxies as they merged to form NGC 7252. This month, we zoom in to look at the central part of the merging galaxy itself, but in colour!
UVIT onboard ASTROSAT imaged this galaxy in the Near UV (around 242 nanometres) and the Far UV (around 148 nanometres). When we divide these two images pixel by pixel, we get an 'ultraviolet colour' image. Imagine a light bulb emitting all visible colours. We will perceive it as a particular colour depending on the fraction of red versus green versus blue light it emits. Similarly, dividing the FUV and the NUV images will tell us what the 'ultraviolet colour' of NGC 7252 is, and how this colour varies across the galaxy. These 'ultraviolet colours' are represented as red to blue in the image here.
FUV − NUV colour map of NGC7252
In the figure, we see a central 'red' region surrounded by a 'blue' ring, with an outer 'red' region. The size of the image is marked in arcseconds (3600 arcseconds make a degree) and equivalently in kpc (1 kpc is 3260 light years). Koshy and his collaborators have modelled this colour to calculate the corresponding ages of the stars that emit in these regions. They have shown that there is a bunch of stars right in the middle, which are around 320 million years old. The surrounding blue ring has stars that are around 250 million years old. The even bluer clumps within the ring are only about 150 million years old. The surrounding larger region of red has stars that are more than 400 million years old.
Remember, NGC 7252 is born out of two galaxies merging together. This merger is a violent event whose effects on the gas in these galaxies is complex. The authors of this study explain how this merger would naturally lead to this scenario where different parts of the galaxy hosts stars of different ages. These have been discussed in detail in https://arxiv.org/pdf/1805.03543.pdf.
KapitaanAli
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Astronomers report the most distant radio galaxy ever discovered
August 8, 2018 , Netherlands Research School for Astronomy
This picture shows the near-infrared image in K band taken using the Large Binocular Telescope in Arizona, with radio emission overlaid in white. The fact that the host galaxy was not detected at infrared wavelengths from where the radio emission originates helped independently confirm the record distance of this galaxy. Credit: Leiden Observatory
After nearly 20 years, the record of the most distant radio galaxy ever discovered has been broken. A team led by Ph.D. student Aayush Saxena (Leiden Observatory, the Netherlands) has found a radio galaxy from a time when the universe was only 7 percent of its current age, at a distance of 12 billion light-years.
The team used the Giant Meter-wave Radio Telescope (GMRT) in India to initially identify the radio galaxy. The distance to this galaxy was then determined using the Gemini North telescope in Hawaii and the Large Binocular Telescope in Arizona by measuring the redshift of the galaxy.
The redshift of z = 5.72 means that the galaxy is perceived as it looked when the universe was only a billion years old. This also means that the light from this galaxy is almost 12 billion years old. The team consists of astronomers from the Netherlands, Brazil, the United Kingdom and Italy. The study announcing these results has been accepted for publication in the Monthly Notices of the Royal Astronomical Society.
Measuring the redshift of a galaxy tells astronomers its distance. The farther away galaxies are, the faster they move away from us. The light from these galaxies therefore appears to be redder, following an effect that is known as the Doppler shift. Therefore, the higher the speed at which a galaxy moves away from us, the greater its redshift.
Radio galaxies are very rare objects in the universe. They are colossal galaxies with a supermassive black hole in their center that actively accretes gas and dust from its surroundings. This activity initiates the launch of high-energy jet streams, which are capable of accelerating charged particles around the supermassive black hole to almost the speed of light. These jets are very clearly observed at radio wavelengths.
The fact that such galaxies exist in the distant universe has surprised astronomers. The discovery of such galaxies at extremely large distances is important for our understanding of the formation and evolution of galaxies. Studying these radio galaxies in detail also sheds light on the formation of primordial black holes, which have driven and regulated the growth of galaxies.
First author Aayush Saxena (Leiden Observatory) says, "It is very surprising how these galaxies have built up their mass in such a short period of time." Co-author Huub Röttgering (Leiden Observatory, the Netherlands) adds: "Bright radio galaxies harbor supermassive black holes. It is amazing to find such objects as early in the history of the universe; the time for these supermassive black holes to form and grow must have been very short."
A radio galaxy with a redshift of z = 5.19 had been the previous record holder since its discovery in 1999. The next generation of radio telescopes, combined with the world's largest optical and infrared telescopes, will be able to detect radio galaxies at even greater redshifts.
More information: A Saxena et al. Discovery of a radio galaxy at z = 5.72, Monthly Notices of the Royal Astronomical Society (2018). DOI: 10.1093/mnras/sty1996
August 8, 2018 , Netherlands Research School for Astronomy
This picture shows the near-infrared image in K band taken using the Large Binocular Telescope in Arizona, with radio emission overlaid in white. The fact that the host galaxy was not detected at infrared wavelengths from where the radio emission originates helped independently confirm the record distance of this galaxy. Credit: Leiden Observatory
After nearly 20 years, the record of the most distant radio galaxy ever discovered has been broken. A team led by Ph.D. student Aayush Saxena (Leiden Observatory, the Netherlands) has found a radio galaxy from a time when the universe was only 7 percent of its current age, at a distance of 12 billion light-years.
The team used the Giant Meter-wave Radio Telescope (GMRT) in India to initially identify the radio galaxy. The distance to this galaxy was then determined using the Gemini North telescope in Hawaii and the Large Binocular Telescope in Arizona by measuring the redshift of the galaxy.
The redshift of z = 5.72 means that the galaxy is perceived as it looked when the universe was only a billion years old. This also means that the light from this galaxy is almost 12 billion years old. The team consists of astronomers from the Netherlands, Brazil, the United Kingdom and Italy. The study announcing these results has been accepted for publication in the Monthly Notices of the Royal Astronomical Society.
Measuring the redshift of a galaxy tells astronomers its distance. The farther away galaxies are, the faster they move away from us. The light from these galaxies therefore appears to be redder, following an effect that is known as the Doppler shift. Therefore, the higher the speed at which a galaxy moves away from us, the greater its redshift.
Radio galaxies are very rare objects in the universe. They are colossal galaxies with a supermassive black hole in their center that actively accretes gas and dust from its surroundings. This activity initiates the launch of high-energy jet streams, which are capable of accelerating charged particles around the supermassive black hole to almost the speed of light. These jets are very clearly observed at radio wavelengths.
The fact that such galaxies exist in the distant universe has surprised astronomers. The discovery of such galaxies at extremely large distances is important for our understanding of the formation and evolution of galaxies. Studying these radio galaxies in detail also sheds light on the formation of primordial black holes, which have driven and regulated the growth of galaxies.
First author Aayush Saxena (Leiden Observatory) says, "It is very surprising how these galaxies have built up their mass in such a short period of time." Co-author Huub Röttgering (Leiden Observatory, the Netherlands) adds: "Bright radio galaxies harbor supermassive black holes. It is amazing to find such objects as early in the history of the universe; the time for these supermassive black holes to form and grow must have been very short."
A radio galaxy with a redshift of z = 5.19 had been the previous record holder since its discovery in 1999. The next generation of radio telescopes, combined with the world's largest optical and infrared telescopes, will be able to detect radio galaxies at even greater redshifts.
More information: A Saxena et al. Discovery of a radio galaxy at z = 5.72, Monthly Notices of the Royal Astronomical Society (2018). DOI: 10.1093/mnras/sty1996
KapitaanAli
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MINERVA-II1: Successful image capture,
landing on Ryugu and hop!
On September 21, the small compact MINERVA-II1 rovers separated from the Hayabusa2 spacecraft (time of separation was 13:06 JST). The MINERVA-II1 consists of two rovers, Rover-1A and Rover-1B. We have confirmed both rovers landed on the surface of asteroid Ryugu. The two rovers are in good condition and are transmitting images and data. Analysis of this information confirmed that at least one of the rovers is moving on the asteroid surface.
MINERVA-II1 is the world’s first rover (mobile exploration robot) to land on the surface of an asteroid. This is also the first time for autonomous movement and picture capture on an asteroid surface. MINERVA-II1 is therefore “the world’s first man-made object to explore movement on an asteroid surface”. We are also delighted that the two rovers both achieved this operation at the same time.
The following is a picture sent from MINERVA-II1.
landing on Ryugu and hop!
On September 21, the small compact MINERVA-II1 rovers separated from the Hayabusa2 spacecraft (time of separation was 13:06 JST). The MINERVA-II1 consists of two rovers, Rover-1A and Rover-1B. We have confirmed both rovers landed on the surface of asteroid Ryugu. The two rovers are in good condition and are transmitting images and data. Analysis of this information confirmed that at least one of the rovers is moving on the asteroid surface.
MINERVA-II1 is the world’s first rover (mobile exploration robot) to land on the surface of an asteroid. This is also the first time for autonomous movement and picture capture on an asteroid surface. MINERVA-II1 is therefore “the world’s first man-made object to explore movement on an asteroid surface”. We are also delighted that the two rovers both achieved this operation at the same time.
The following is a picture sent from MINERVA-II1.
[open in another window]Figure 1: Image captured by Rover-1A on September 21 at around 13:08 JST. This is a color image taken immediately after separation from the spacecraft. Hayabusa2 is at the top and the surface of Ryugu is bottom. The image is blurred because the shot was taken while the rover was rotating.
(Image credit: JAXA)
[open in another window]Figure 2: Image captured by Rover-1B on September 21 at around 13:07 JST. This color image was taken immediately after separation from the spacecraft. The surface of Ryugu is in the lower right. The coloured blur in the top left is due to the reflection of sunlight when the image was taken.
(Image credit: JAXA)
[open in another window. (rotated image)]Figure 3: Image captured by Rover-1A on September 22 at around 11:44 JST. Color image captured while moving (during a hop) on the surface of Ryugu. The left-half of the image is the asteroid surface. The bright white region is due to sunlight.
(Image credit: JAXA).
RPK
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Farhan Bohra
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Which idiot told you north star is fixed? There are 26,000 years precession period of the earth. And in 13000 years Vega will be North Star.
Same as South Star, which I think you never heard about with the IQ you hold.
Verve
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Farhan Bohra
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If you are idiot, then that doesnt mean you thinking all are@ mathematical theories regurgitated above!
https://www.eso.org/public/outreach/eduoff/aol/market/experiments/advanced/skills304.html
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