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David Knisely
Postmaster
Reged: 04/19/04
Posts: 6785
Loc: Beatrice, Nebraska
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Seems to me that a number of years ago, a similar announcement was made about the Van Briesbock objects VB8 and VB10, possibly as early as the late 1980's (both turned out to be a very cool late M-class stars). That sort of faded away, but a number of years later, a similar claim was made about a different star and a companion object (the companion apparently turned out to be more distant). I guess I will wait until we get a little more data before this one is a confirmed "first planetary image". Clear skies to you.
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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
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Kobayashi
sage
Reged: 07/10/08
Posts: 291
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Quote:
Because I read the observatories report (the paper incorrectly labelled that simulation 'a first image', that 'image' is within the actual report), after 'viewing the first link'...I posted concerns for this 'lack of proper concept'...in calling that 'constructed simulated picture'..."a first image".
I still don't understand what you're trying to say. It's not a simulation; it's an actual image, made by combining several raw images taken with a telescope, with help from an adaptive optics system. The telescope focuses light, and the adaptive optics correct for atmospheric distortion. The result is that the image is formed on a CCD detctor, and recorded. Several such images are combined to reduce noise, as is done when amateurs use RegiStax to combine webcam images. In what way is this a "simulation" and not an "image"? There's nothing here that can be called a simulation; it's just very basic image processing.
So maybe you can explain to me, what is your definition of an "image," and in what way does this one not qualify?
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-- Ken Kobayashi
Edited by Kobayashi (09/21/08 11:06 PM)
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charlie g
sage
Reged: 10/05/07
Posts: 287
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Hello Ken, The 'Gemini Observatory' gives an absurdly enlarged planet (yes they surround it with a red circle too), they have a 'size ratio between star and her planet totally made up ( and as I said...very similar to relationship between Jupiter and her moon,Ganymeade), the distance between TWO DOTS of merged data sets is the only thing the inserted one arcsecond scale marker relates to.
There IS NO 'FIRST IMAGE'...a sonogram of our dear child was an:"image", 'infra-red IMAGES abound in our reality'...this IS NOT AN IMAGE...IT'S A SIMULATION SUGGESTING AN OPTICAL IMAGE...NO TRUE SCALE BETWEEN SIZE OF PLANET DISC AND SIZE OF PARENT STAR...okay 'the brilliance of the star gives false impression of 'one arcsecond star diameter'...so what's 'you excuse for huge size of 'planet disc'?...Why in an observational activity with deep grounding in science do you 'have a block' over: 'a simulation to represent an important and new data-set...IS NOT A FIRST IMAGE?
Why 1)with no true size ratio, 2) with no true color of that HUGE planet disc, 3) oddly...no correction for photosheric limit of 'the parent star we know to be our Suns size (but younger)...why do you resist calling a simulation of a data set what it is...a simulated picture?
With robotic telescopes/microscopes/oceanic sub-surface and surface recorders/satellite imagers/planetary off earthprobes...now more than ever we need be correct in :'what is a first image', and what is a data set processed as a simulated picture.
I lastly specifically 'reach out to you, Ken...1) the planet disc size is TOTALLY MADE UP, 2) no indication of relative star size(with respest to that huge planet disc), colors of that huge planet disc arbitray...I say this demands calling 'it' a simulation. Go slow on me, the technology, my digital camera, astronomic 'processing/image stacking'...please answer for this simple but important problem I have with:"Gemini Observatory first image".
thanks much...but so far I hear nothing about my concerns...this is a simulation of important data set.
charlie guevara, NJ,US
In highschool we played 'the planets'...you can guess how far from 'the flagpole is the Sun'...was Earth, was Mars, was Jupiter! That 'simulation has no realitybased sized ratios of the depicted planet disc, of the 'parent star(said to be size of our Sun,only younger)
Ken, thanks for shareing...but forget about me, forget about caffiene, forget about 'Gemini Observatory'...data set are depicted all the time..."first Image" demands an image...not a simulated image.
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Kobayashi
sage
Reged: 07/10/08
Posts: 291
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OK, I think what you're trying to say is that "an image of <something>" implies that it shows details in <something>.
I'm sorry, but that's just not correct. An image is simply data showing brightness as a function of position. It's a measured map of brightness.
If someone did a spectroscopic analysis of the star, deduce the existence of a planet based on the Doppler shift of the star, then made a picture showing what the star/planet system should look like, then that would be a simulation.
But that's not what happened here. They pointed a telescope at this star, acquired some images with a CCD, and said "hey look, there's a small dot 2.2 arcseconds away from the star." There is no other type of observation involved in making that picture. It's 100% honest and correct to call that an "image of a possible planet." I can't think of what else you'd call it.
If someone took a wide-field photo of Jupiter showing but not resolving the Galilean satellites, would you object to calling it "an image of Jupiter and its moons"? What possible rationale would you have to call it "an image of Jupiter and a simulation of its moons"??
Or for that matter, any image of a double star has the sizes of the stars severely exaggerated. This picture of Albiero, for example, shows the two stars much larger than to scale, because that's the resolving limit of the telescope/camera they used. But that's still an "image of Albireo," not a simulation.
Quote:
Hello Ken, The 'Gemini Observatory' gives an absurdly enlarged planet (yes they surround it with a red circle too), they have a 'size ratio between star and her planet totally made up ( and as I said...very similar to relationship between Jupiter and her moon,Ganymeade),
The objects look oversized because it's an actual image and not a simulation. They show up as large discs because that's the resolving limit of the telescope.
Quote:
the distance between TWO DOTS of merged data sets is the only thing the inserted one arcsecond scale marker relates to.
Actually, it also relates to the resolution and point spread function (PSF) of the telescope. It's significant that the planet looks like a ~0.1 arcsecond disc; it tells us that's what the resolution of that telescope system is. We can also see that the PSF has a broad base, a "halo" of light about 1" arcsecond, so that's about the limit of where it can detect a very dim companion next to a bright star.
Quote:
Why 1)with no true size ratio, 2) with no true color of that HUGE planet disc, 3) oddly...no correction for photosheric limit of 'the parent star we know to be our Suns size (but younger)...why do you resist calling a simulation of a data set what it is...a simulated picture?
1) The telescope system is nowhere near good enough to show a true size ratio. But it is good enough to resolve the two as distinct dots, and give us the relative brightness and position, which is darn impressive and worth bragging about (or publishing).
2) Actually it does show a "true" color because they combined images taken in different wavelength bands. At least, it's as "true" as your average color photo. The paper also shows an actual measured spectrum.
3) We can deduce the star's size by measuring its spectrum and applying our knowledge of stellar evolution. But if we used such knowledge to tweak the image, then it's no longer a real image; it becomes a simulation.
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I lastly specifically 'reach out to you, Ken...1) the planet disc size is TOTALLY MADE UP, 2) no indication of relative star size(with respest to that huge planet disc),
Once again - the discs are big because it's an actual image, and not corrected for anything. If we used knowledge from other types of observations, then it becomes a "made up" picture.
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-- Ken Kobayashi
Edited by Kobayashi (09/22/08 09:17 AM)
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jupiterzkool
Pooh-Bah
Reged: 05/08/06
Posts: 1343
Loc: Pasadena, CA
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Ken,
Nice responses.
Charlie,
I really don't think you are getting the process involved with imaging astrophysical objects. I am not sure how folk here can better explain it than they already have. The paper linked above gives the technique used. If you still do not understand after reading it, I encourage you to read more about modern astronomical imaging techniques. Perhaps someone can recommend a good book or journal article.
Regardless, of whether you think of this an image or simulation, that is not the important point. It is the science that can be attained by resolving both objects and observing them individually over time. One cannot learn much about the planet without this first time observation.
Best regards,
Scott
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Scott G. Edgington, Planetary Scientist
Cassini-Huygens: Mission to Saturn & Titan
Yes, Asia, John Wetton Fan
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charlie g
sage
Reged: 10/05/07
Posts: 287
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It resolved or showed two data sets, dipicted as Dots. Please don't 'break in with how impressive this is...we all cheer the science achievements'. Nothing about the position of : two points of data sets, with a one arcsecond scale bar overlayed..."is a first image"...it's a simulation. Please don't 'drift into commercial film rendition of true color', don't bring up:'first time observation of a planet'. A 'radar image of Venus below its weather', an 'optical image of Gaspara', these are 'images'...not simulations.
Don't bring up:'first time observations', Scott...simulation images are constructed from observations all the time (thank you for clapping hands for simple points of discussion, yet remaining silent on my various points of concern(calling a simulated image of data sets a 'first image').
Your particular comment, which your list as: " 3)We can deduce the stars size by measureing its spectrum and applying our knowledge of stellar evolution .", Ken , this process is exactly the reason this 'first image is a simulation of that system 500 light years out there.
The only content of that 'first image' are position between two points (not discs/not even dots...as points...no 'real color assignable to points'. Those interwoven reds/greens/whatever...have no assignability to 'points' of plotted data sets.
Quietly I did read the paper, as well as the first link, Scott. It getts boreing pretty quick to have your 'saw repeated' of: 'your not getting the process'. Astrophysical simulations are not the same as astrophysical imageing, Scott. I really don't think your getting my concern, Scott. Perhaps you can read this post and specifically react to : 'Kens point 3)...dedeuced size from knowledge of stellar evolution'...this can make for important/valid...simulated images. charlie guevara NJ,US
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jupiterzkool
Pooh-Bah
Reged: 05/08/06
Posts: 1343
Loc: Pasadena, CA
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Charlie,
Perhaps learning more about the NIRI camera will help? It has a 1024 x 1024 array with each pixel having 0.0219 arc sec at f/32. It takes images. Nothing is "simulated" about it.
-S
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Scott G. Edgington, Planetary Scientist
Cassini-Huygens: Mission to Saturn & Titan
Yes, Asia, John Wetton Fan
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Kobayashi
sage
Reged: 07/10/08
Posts: 291
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Quote:
It resolved or showed two data sets, dipicted as Dots.
Exactly. They pointed a telescope at the star and took a picture. It's an image that shows two dots.
Quote:
Your particular comment, which your list as: " 3)We can deduce the stars size by measureing its spectrum and applying our knowledge of stellar evolution .", Ken , this process is exactly the reason this 'first image is a simulation of that system 500 light years out there.
But that's NOT what this picture is. It's an actual image that was recorded by a CCD. The telescope+camera didn't know what to expect, it just took a picture, which is what we see in the paper. Which part of this are you not understanding?
Quote:
The only content of that 'first image' are position between two points (not discs/not even dots...as points...no 'real color assignable to points'. Those interwoven reds/greens/whatever...have no assignability to 'points' of plotted data sets.
Exactly right. It's an image that shows us that the star has a very dim companion object 2.2" away. Without that image, we wouldn't know how far that companion is, or in which direction. We may not even know there is a companion object at all.
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Astrophysical simulations are not the same as astrophysical imageing, Scott.
Quite right. And this picture is an example of imaging.
Quote:
3)...dedeuced size from knowledge of stellar evolution'...
I was explaining what the image was NOT.
For the millionth time - this is a picture produced by a camera. That's what an image is. The camera doesn't know any stellar physics. The camera doesn't know what the scientists expected it to see. The scientists didn't even know what they expected to see.
I'm still completely baffled as to what you are complaining about. Do you not understand that scientists use images to detect objects, and measure distances between objects? Even if we can't see detail on the surface of the object, an image can still tell us where the object is, how bright it is, how far it is from another object, etc. These are all useful measurements, and you get these numbers from images.
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-- Ken Kobayashi
Edited by Kobayashi (09/23/08 03:08 AM)
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Jay_Bird
professor emeritus
Reged: 01/04/06
Posts: 680
Loc: Nevada 36N 115W
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What intrigues me about this photo is that it's a preview of what a large space- (or moon-)based telescope might show around many nearby stars someday. It's an earth-based preview visible because of the lucky circumstance of a bigger-than-Jupiter planet at a Pluto-like distance from it's parent star, a pairing that is possible to resolve even through our atmosphere.
Barnard's famous early Milky Way plates and many photos since show bright star images swollen compared to the faintest recorded stars or minor planets. So does this CCD based image of a Jupiter-like world peeking out of the dazzle of it's star. Scintillation at the edges of the star image was not the same for each filtered exposure, hence the short spiky red and green artifacts at the edge of the star's swollen image that look a little like prominences (but are not). Overall this may not look too different from views seen by 19th Century astromomers visually hunting for faint moons within our solar system.
In short, it's a direct image, albeit recorded in near-infrared light and presented in visible colors (just like images on the old color infrared films).
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'these things stand like stone - kindness in another's troubles, courage in your own' Gordon
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zee
super member
Reged: 07/04/07
Posts: 134
Loc: Arizona (varies)
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could someone direct me to an explanation of what the difference is between a really big Jupiter and a L or T class (I think they're calling them that nowadays, sub-M class, I mean, not t-Tauri) star. I'm curious why this is a planet, you see, and not just a double-star system.
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8" Orion classic dob
15x70 Celestron Skymaster
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llanitedave
Humble Megalomaniac
Reged: 09/26/05
Posts: 10483
Loc: Amargosa Valley, NV, USA
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The difference is that a brown dwarf produces its own energy via fusion, although only deuterium fuses at such a small mass. A planet is not massive enough to undergo fusion. There's a blurry line between the two, and they are usually determined both by calculated mass and luminosity characteristics. But unless the measured mass/energy spectrum of the companion is obviously on one side of the line or the other, very often it's hard to say definitely what you're looking at.
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"S.O.E." (Sauron's Other Eye) 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror
Next Project: The "Eye of Sauron" Observatory!
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zee
super member
Reged: 07/04/07
Posts: 134
Loc: Arizona (varies)
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thanks (am I'm relieved it wasn't a stupid question). I was skeptical of the definition of the thing as a planet both because of the mass and distance from the main star. So would a fairer title for the thread would be "first blurry image of some massive body that may or may not be a planet"?
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8" Orion classic dob
15x70 Celestron Skymaster
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llanitedave
Humble Megalomaniac
Reged: 09/26/05
Posts: 10483
Loc: Amargosa Valley, NV, USA
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Quote:
So would a fairer title for the thread would be "first blurry image of some massive body that may or may not be a planet"?
Well, the researchers are calling it a planet, so they seem to have some indication that it's not a brown dwarf. I would guess that the distance to the primary prevents them from getting a mass measurement, so they would be going by the objects surface temperature. A deuterium-fusing brown dwarf would maintain a certain temperature, while a non-fusing planet would cool down at a faster rate. So once the bodies achieved sufficient age, the planet would be noticeably cooler than a brown dwarf.
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"S.O.E." (Sauron's Other Eye) 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror
Next Project: The "Eye of Sauron" Observatory!
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Rick Woods
Post Laureate
Reged: 01/27/05
Posts: 4312
Loc: Inner Solar System
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Quote:
Quote:
So would a fairer title for the thread would be "first blurry image of some massive body that may or may not be a planet"?
Well, the researchers are calling it a planet...
But a lot of them are calling Pluto not a planet. Seems to me that Pluto is more planet-like than an object 3 times the size of Jupiter, at 330 AU's from the parent star and 1500 degrees C.
Maybe it's a mauve dwarf. Or a puce dwarf. It's bigger and hotter than brown dwarves are.
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- Rick
14" LX200GPS
8" Meade 826C
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llanitedave
Humble Megalomaniac
Reged: 09/26/05
Posts: 10483
Loc: Amargosa Valley, NV, USA
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Quote:
But a lot of them are calling Pluto not a planet.
I was trying very hard not to open that can of worms. A solar system planet is now defined differently, and by a different group of people, than is an extrasolar planet. You can't win. 
Quote:
Seems to me that Pluto is more planet-like than an object 3 times the size of Jupiter, at 330 AU's from the parent star and 1500 degrees C.
Maybe it's a mauve dwarf. Or a puce dwarf. It's bigger and hotter than brown dwarves are.
If it's fusing, it's a brown dwarf. If it's not, it's a planet, unless it's in the Solar System. That's how I understand it, at least. Its temperature depends both on its mass and its age, with I suppose an unknown contribution from differences in composition. A younger mega-planet might just be a little hotter than an old brown dwarf (they just ain't what they used to be!)
edit: According to the news release, the object's spectra matches a body of 8 times Jupiter's mass. That's far less than what would be required to make a brown dwarf.
Edited by llanitedave (09/30/08 07:07 PM)
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Rick Woods
Post Laureate
Reged: 01/27/05
Posts: 4312
Loc: Inner Solar System
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I figured I'd get busted on that "bigger than a brown dwarf' statement - I went by (faulty) memory and didn't check my facts.
Great picture, though, whatever the heck it turns out to be.
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- Rick
14" LX200GPS
8" Meade 826C
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jayscheuerle
Carpal Tunnel
Reged: 01/16/06
Posts: 2990
Loc: S. Philadelphia, PA
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We like to classify things and our simplified view of the universe permitted that in the past, but variation in bodies covers a much wider range than we're intimate with. There's going to be a lot of grey area between classifications that we'll eventually find objects that fall within.
Solid classifications within a fluid world eventually break down. - j
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12" Green Goblin (trusser w/Protstar secondary and OWL refigured primary)• 6" f/5 Eero2 ball-scope • 6" f/5 Frankenscope • Garrett Optical 10x50 binos • Edmund 8" yoke-mounted red-tube reflector • Edmund 6" GEQ red-tube reflector (on loan to Dad)
Gone, but with lessons learned:
Skyquest XT8 • NexSTar 8i • Eeroscope 6" f/5 ball(sacrifice was not in vain) • Vixen ED80sf • Edmund red-tube 4.25" f/10 • Edmund Astroscan
Facts are stubborn things.
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Rick Woods
Post Laureate
Reged: 01/27/05
Posts: 4312
Loc: Inner Solar System
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Jay,
That's true, and all the more reasons to keep classifications broad and inclusive. "Planet" is a great candidate for a broad classification, including all the myriad flavors of planets we're discovering; not the tight, locked-in, ridiculous definition that currently enjoys official sanction. Right here, we appear to have a whole new type of planet; or at least, a Jovian-type planet on steroids.
Dave: I thought a brown dwarf was a star where fusion never actually ignited? Or am I wrong there too?
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- Rick
14" LX200GPS
8" Meade 826C
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llanitedave
Humble Megalomaniac
Reged: 09/26/05
Posts: 10483
Loc: Amargosa Valley, NV, USA
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Rick, my understanding is that a brown dwarf can't ignite normal hydrogen, but does fuse deuterium.
However, my understanding proves to be simplistic, as usual.
I think this is a case where Wikipedia can be relied on.
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"S.O.E." (Sauron's Other Eye) 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror
Next Project: The "Eye of Sauron" Observatory!
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