Design of the VIS (short for VISible) optical camera was a pan-European project led by UCL’s Mullard Space Science Laboratory.
https://www.ucl.ac.uk/mathematical-.../jun/space-telescope-shed-light-dark-universe
VIS will take images nearly as sharp as the Hubble Space Telescope, but it will cover a much larger area of the sky – covering the same area in one day as Hubble covered over 25 years.
https://www.ucl.ac.uk/mathematical-.../jun/space-telescope-shed-light-dark-universe
VIS will take images nearly as sharp as the Hubble Space Telescope, but it will cover a much larger area of the sky – covering the same area in one day as Hubble covered over 25 years.
I guess we must wait a bit for Euclid's data to start rolling in. Meantime I am beavering away at Kerr Black Holes, which are the uncharged rotating ones that seem to be the main extreme gravity event in our Universe.
https://ysjournal.com/physics/kerr-vs-schwarzschild-black-holes/
It fascinates me that at a certain spin parameter in Kerr Black Holes , the event horizons and ergospheres line up most symmetrically:
Just my mathematical approach... there is something special about that!
The formula seems to suggest that this happens when the square root term goes to zero, as in easy Quadratic equations. a is the spin parameter, which can be defined as a length or a dimensionless ratio.
r is various radii.
https://en.wikipedia.org/wiki/Kerr_metric
Scientists seem to have discovered an enormous spinning Black Hole binary 5 Billion light years away called OJ 287. It has a period of 12 years, but this is shortening by 20 days every 12 years.
https://en.wikipedia.org/wiki/OJ_287
It flares regularly when the secondary passes through the accretion disk of the primary as bright as our whole Milky Way galaxy!
How big are these Black Holes?
Whoppers! Of course a lot of this is guesswork. If the primary is spinning faster than expected, it can be smaller apparently. LIGO is not up to detecting current gravitational waves, but the merger will be unmissable. A spectacular event is just 10,000 years around the corner. 😎
https://ysjournal.com/physics/kerr-vs-schwarzschild-black-holes/
It fascinates me that at a certain spin parameter in Kerr Black Holes , the event horizons and ergospheres line up most symmetrically:
Just my mathematical approach... there is something special about that!
The formula seems to suggest that this happens when the square root term goes to zero, as in easy Quadratic equations. a is the spin parameter, which can be defined as a length or a dimensionless ratio.
r is various radii.
https://en.wikipedia.org/wiki/Kerr_metric
Scientists seem to have discovered an enormous spinning Black Hole binary 5 Billion light years away called OJ 287. It has a period of 12 years, but this is shortening by 20 days every 12 years.
https://en.wikipedia.org/wiki/OJ_287
It flares regularly when the secondary passes through the accretion disk of the primary as bright as our whole Milky Way galaxy!
How big are these Black Holes?
Whoppers! Of course a lot of this is guesswork. If the primary is spinning faster than expected, it can be smaller apparently. LIGO is not up to detecting current gravitational waves, but the merger will be unmissable. A spectacular event is just 10,000 years around the corner. 😎
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I wish they would be more precise when info is passed to the public.
VIS for instance is mid visible to very near infrared. The NASA sensor extends the infrared
A 1.2m dia mirror can not match the resolution of a 2.4m mirror as used by Hubble. Or capture light at the same rate which means more sensitive sensors / longer exposures. It sounds like it will cover a larger area of the sky with a single "photo" but light intensity on the sensor is proportional to 3 factors. Mirror diameter the field of view and sensor area. Mirror diameter due to it's effect on the capture area.
It seems that the NASA detector uses 16 sensors and they also provided 4 spares.
All interesting as it looks like it takes ideas from "smaller" ground based telescopes used for useful work and sticks them in outer space. All sorts of aspects get more difficult as diameter increases and studying longer wavelengths means that the optics do not need to be produced to the same accuracy as shorter.
LOL Singularities. One solution could be that they can not exist. In other words matter can not be compressed to zero.
VIS for instance is mid visible to very near infrared. The NASA sensor extends the infrared
A 1.2m dia mirror can not match the resolution of a 2.4m mirror as used by Hubble. Or capture light at the same rate which means more sensitive sensors / longer exposures. It sounds like it will cover a larger area of the sky with a single "photo" but light intensity on the sensor is proportional to 3 factors. Mirror diameter the field of view and sensor area. Mirror diameter due to it's effect on the capture area.
It seems that the NASA detector uses 16 sensors and they also provided 4 spares.
All interesting as it looks like it takes ideas from "smaller" ground based telescopes used for useful work and sticks them in outer space. All sorts of aspects get more difficult as diameter increases and studying longer wavelengths means that the optics do not need to be produced to the same accuracy as shorter.
LOL Singularities. One solution could be that they can not exist. In other words matter can not be compressed to zero.
Something "soft" "physics":
If "space-tact" is bent, are "space(-ing-s)" and "tact" bent in the same proportion;-?
If "space-tact" is bent, are "space(-ing-s)" and "tact" bent in the same proportion;-?
If a "bear" "sharts" in the: woods" is its "skid" "mark" bent in the same proportion/;]?
It's fun to post random nonsense!
It's fun to post random nonsense!
Gravity is produced by mass. Mass deforms spacetime like a bowling ball on a mattress, anything in the vicinity of Earth’s accelerating field will fall into the dent in spacetime formed by the bowling ball. Also like an ant falling into an ant lion’s hole in the sand.
"... anything [...] will fall into the dent in spacetime formed by the bowling ball."
The bowling ball falls into the "space-time" bended by it;-?
The bowling ball falls into the "space-time" bended by it;-?
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Angular resolution is the term astronomers use to describe the "sharpness" of an image.
There are two factors that affect how sharp an image is - the diameter of the mirror and the wavelength being observed.
If Euclid has a diameter half that of Hubble, it will have half the resolution of Hubble when observing at the same wavelength.
However, we also have to take into account that the resolution will be different for different wavelengths.
"..random nonsense"
As long as zee kooks stay in the lounge sandbox preserving the rest of the forum all is good. ::-)
As long as zee kooks stay in the lounge sandbox preserving the rest of the forum all is good. ::-)
No argument;-)
Do you have the solution:
If "space-tact" is bent, are "space(-ing-s)" and "tact" bent in the same proportion;-?
Do you have the solution:
If "space-tact" is bent, are "space(-ing-s)" and "tact" bent in the same proportion;-?
Same with Hubble
Looking further both Hubble and Euclid basically use an F24 telescope. Hubble covers 144 arc secs deep field, 2.6 arc min wide field and 66arc secs planetary. F12.9 wide field and F30 planetary. The deep field seems to use both.
Euclid - so far dead links looking for similar info other than it is F24 but has a stop / aperture at the front. That can help with field of view
Instruments
- VIS, a camera operating at visible wavelengths (530–920 nm) made of a mosaic of 6 × 6 e2v Charge Coupled Detectors, containing 600 million pixels, allows measurement of the deformation of galaxies[20]
- NISP, a camera composed of a mosaic of 4 × 4 Teledyne H2RG detectors sensitive to near-infrared light radiation (920–2020 nm) with 65 million pixels, is designed for the following:
- provide low-precision measurements of redshifts, and thus distances, of over a billion galaxies from multi-color (3-filter (Y, J and H)) photometry (photometric redshift technique); and
- use a slitless spectrometer to analyse the spectrum of light in near-infrared (920–1850 nm), to acquire precise redshifts and distances of millions of galaxies with an accuracy 10 times better than photometric redshifts, and to determine the baryon acoustic oscillations.[21]
Lot of NOISE being posted in this thread, IMO. And very little SIGNAL. SHAME on certain people! 🙁
To address @AjohnL and his obsessive concerns about the optics in the Euclid Space mission. I really don't think the ESA is lying to us.
Just trying to keep it simple.
It's a widefield space camera. Actually a Korsch application of three mirrors and a big sensor. Probably more useful than Hubble in its ability to gather lots of detail about the Cosmos.
https://en.wikipedia.org/wiki/Three-mirror_anastigmat
Since Dietrich Korsch patented this simple application of optics and mathematics about 50 years ago, he must now be running to the Bank giggling that he is finally getting a substantial cash royalty.
Personally I have little interest in the details of the Euclid camera/telescope. It is designed to do a job, mapping Billions of Galaxies, and as cheaply as possible. Though clearly the optical sensor is far better than the 20-y-o stuff on Hubble.
Just think, the new Apple iPhones can take good images of paper documents in near darkness these days. A feat impossible 20 years ago.
What Euclid is up to is this:
How it does it:
An exploration of Dark Matter and Dark Energy. It's actually more of a statistical analysis, so the more samples the better, rather than focussed on a particular single object. Think of it as a pair of low-powered but huge light-gathering Binoculars, rather than a narrow high-powered Telescope.
Each useful in their own ways. Hope that clears it up.
To address @AjohnL and his obsessive concerns about the optics in the Euclid Space mission. I really don't think the ESA is lying to us.
Just trying to keep it simple.
It's a widefield space camera. Actually a Korsch application of three mirrors and a big sensor. Probably more useful than Hubble in its ability to gather lots of detail about the Cosmos.
https://en.wikipedia.org/wiki/Three-mirror_anastigmat
Since Dietrich Korsch patented this simple application of optics and mathematics about 50 years ago, he must now be running to the Bank giggling that he is finally getting a substantial cash royalty.
Personally I have little interest in the details of the Euclid camera/telescope. It is designed to do a job, mapping Billions of Galaxies, and as cheaply as possible. Though clearly the optical sensor is far better than the 20-y-o stuff on Hubble.
Just think, the new Apple iPhones can take good images of paper documents in near darkness these days. A feat impossible 20 years ago.
What Euclid is up to is this:
How it does it:
An exploration of Dark Matter and Dark Energy. It's actually more of a statistical analysis, so the more samples the better, rather than focussed on a particular single object. Think of it as a pair of low-powered but huge light-gathering Binoculars, rather than a narrow high-powered Telescope.
Each useful in their own ways. Hope that clears it up.
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This analysis relies on spectral resolution, i.e., the ability to resolve features in the electromagnetic spectrum.
In simple terms spectral resolution is the smallest difference in wavelengths that can be distinguished at a particular point in the spectrum.
Who says I suspect that? For some reason I failed to find the detail you posted,
I'm more interested in how and which camera gives the wide a field.
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Chinese scientists have recently found key evidence for the existence of nanohertz gravitational waves at a 4.6-sigma statistical confidence level.
Detection of nanohertz gravitational waves is very challenging due to their extremely low frequency, where the corresponding period can be as long as several years and wavelengths up to several light-years. So far, long-term timing observation of millisecond pulsars with extreme rotational stability is the only known method for effectively detecting nanohertz gravitational waves.
https://phys.org/news/2023-06-scientists-key-evidence-nanohertz-gravitational.html
Detection of nanohertz gravitational waves is very challenging due to their extremely low frequency, where the corresponding period can be as long as several years and wavelengths up to several light-years. So far, long-term timing observation of millisecond pulsars with extreme rotational stability is the only known method for effectively detecting nanohertz gravitational waves.
https://phys.org/news/2023-06-scientists-key-evidence-nanohertz-gravitational.html
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