Mission to build world's most advanced telescope reaches major milestone

Aug 01, 2013 by Stuart Wolpert
Artist's rendering of Thirty Meter Telescope

(Phys.org) —With the signing last week of a "master agreement" for the Thirty Meter Telescope—destined to be the most advanced and powerful optical telescope in the world—the University of California and UCLA moved a step closer to peering deeper into the cosmos than ever before.

The agreement, signed by UC President Mark Yudof and several international partners, formally outlines the telescope project's goals, defines the terms of its construction and establishes its governance structure, design and financing.

Work on the Thirty Meter Telescope (TMT), named for its 30-meter primary mirror—three times the diameter of the largest existing telescopes—is scheduled to begin in April 2014 atop Hawaii's dormant Mauna Kea volcano. The TMT's scientific operations are slated to start in 2022.

UCLA researchers will play a significant role in the development and use of the TMT, which will enable astronomers to study stars and other objects throughout our solar system, the Milky Way and neighboring galaxies, and galaxies forming at the very edge of the , near the beginning of time.

The project is a collaboration among universities in the United States and institutions in Canada, China, India and Japan, with major funding provided by the Gordon and Betty Moore Foundation.

"UCLA is taking a lead role in defining the science for this monumental, international project," said Andrea Ghez, a professor of physics and astronomy who holds UCLA's Lauren B. Leichtman and Arthur E. Levine Chair in Astrophysics.

Ghez, who has served on the TMT science advisory committee since its first meeting 13 years ago, described the master agreement as an important milestone for the UC system, UCLA and the field of astronomy.

"One reason why we want to build TMT is to delve into the most fundamental workings of our universe," she said. "It is truly amazing to think about what TMT will teach us about the universe."

An artist's rendering of the Thirty Meter Telescope

Creating cutting-edge instruments for the TMT

UCLA professor of astronomy James Larkin is one of those excited about the TMT's potential. He is the principal investigator for the Infrared Imaging Spectrograph (IRIS), one of three scientific instruments that will be ready for use with the TMT when the telescope begins operation.

"IRIS is an imaging spectrograph that perhaps can best be described as a sophisticated camera that takes small images at 2,000 different wavelengths simultaneously," Larkin said. "Or it can be thought of as a spectrograph that takes 10,000 adjacent spectra over a rectangular area of the sky."

The instrument will be able to produce images three times sharper than what is currently achievable with the two powerful W.M. Keck telescopes on Mauna Kea and many times sharper than the Hubble Space Telescope, Larkin said. IRIS will image planets that are forming but are often too dim and red to be detected by smaller telescopes, and it will be the only one of the three TMT instruments to magnify images to the theoretical diffraction limit.

"Exploring the universe at this unprecedented resolution and sensitivity means we will be surprised by what we find," he said. "IRIS has a wide range of science objectives, ranging from chemical analysis of the surfaces of solar system moons like Titan and Europa, to following the evolution of galaxies over the past 13 billion years, to searching for the first stars in the very early universe."

With the most sensitive spectroscopy available anywhere in the near-infrared, IRIS will yield the first real understanding the physical nature of these early galaxies, a key goal of research in cosmology and astrophysics.

IRIS is a joint project involving more than 50 astronomers from the U.S., Canada, Japan and China, and many of the instrument's most crucial components will be designed and built at UCLA's Infrared Laboratory for Astrophysics, founded more than 20 years ago by Ian S. McLean, who is the lab's director and a UCLA professor of physics and astronomy.

The TMT, McLean said, will enable astronomers to see not only much fainter objects but also to resolve them in much greater detail.

"Both of these attributes are crucial for almost all of the frontier areas of modern astrophysics, from studies of nearby exoplanetary systems to probing the most distant objects in the universe," he said. "The TMT is precisely the right kind of scientific tool to complement national facilities under development, such as the James Webb Space Telescope. We are all very excited that the TMT master agreement is signed."

In 1989, at the beginning of the era of the twin W.M. Keck telescopes—currently the world's largest optical and infrared telescopes—UCLA set up its infrared astrophysics lab to develop state-of-the-science instruments for them. All four of the currently operational infrared cameras and spectrometers on the Keck telescopes were built entirely or in part at UCLA. McLean expects UCLA's infrared lab to play a similar role with the TMT.

The concept of a telescope three times larger and with nine times more light-gathering power than the Keck telescopes was first envisaged nearly 15 years ago, and UCLA has played a major role in defining the type of instruments needed for such a telescope. IRIS, under Larkin's leadership, is one example, McLean said. Another proposed TMT instrument, the Infrared Multi-Slit Spectrometer (IRMS), will be a near-replica of the successful MOSFIRE instrument that McLean delivered to the W.M. Keck Observatory in 2012.

With the sharpest and most sensitive images ever taken in the near infrared, the TMT and IRIS will reveal the universe in new ways, exploring everything from dwarf planets at the orbit of Pluto to the most distant galaxies ever explored near the dawn of time, McLean said.

The twin 10-meter Keck telescopes have "attracted many distinguished faculty, trained students at all levels and served the people of California and the world with inspiring discoveries and technological leadership," said McLean. "The University of California will continue that tradition of leadership and excellence with its participation in the TMT project, and UCLA will play a key role through the development and exploitation of infrared spectroscopy and high-resolution imaging technology."

Solving the mysteries of black holes with the TMT

UCLA's Ghez, who leads the development of the Galactic Center project, said her research will be greatly enhanced by the Thirty Meter Telescope.

Ghez and her colleagues discovered a supermassive black hole at the center of the Milky Way that has a mass approximately 4 million times that of our sun. Such mysterious and intriguing black holes, which were predicted by Einstein's theory of general relativity, provide remarkable laboratories for the study of physics in extreme environments.

The TMT, Ghez said, will identify and map the orbits of fainter stars close to our black hole, extending our knowledge of physics with a fundamental test of Einstein's theory. Because stars in the vicinity of the black hole will be affected by the presence or absence of dark matter, their orbits will significantly constrain our current model of dark matter, which is central to our understanding of galaxy formation.

TMT will also extend our ability to measure accurate masses of black holes in more distant galaxies and in low-mass galaxies, likely revealing when and how black holes are "fed," Ghez said.

By revealing details about resolved stellar populations in nearby galaxies, the TMT and IRIS will directly probe the formation of nearby stellar systems like our own Milky Way. Because it will be possible to measure the mass distributions of stars in a variety of new environments and in galaxies outside of the Milky Way, IRIS will help scientists learn whether stars form differently under different conditions.

In the distant universe, IRIS's ability to image and study the internal workings of early galaxies will represent a major breakthrough in the study of galaxy formation during the known peak period of star formation.

The Thirty Meter Telescope is a collaboration of the University of California, the California Institute of Technology, the Association of Canadian Universities for Research in Astronomy, the National Astronomical Observatory of Japan, a consortium of Chinese institutions led by the National Astronomical Observatories of the Chinese Academy of Sciences, and institutions in India supported by India's Department of Science and Technology.

Explore further: Hubble shows farthest lensing galaxy yields clues to early universe

More information: www.tmt.org/

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User comments : 55

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Matthewwa25
2.7 / 5 (12) Aug 01, 2013
Wonderful!!!
verkle
3.2 / 5 (13) Aug 01, 2013
Superb! Celestial research keeps getting more exciting.
Looking forward to this telescope's completion.
barakn
2.6 / 5 (5) Aug 02, 2013
It's unfortunate that angular resolution varies as the diameter of the collecting surface but light-gathering power varies with the area, or the diameter squared. Astronomers appear to have been sucked into some variant of a penis-size competition that sacrifices the ability to see the small for the ability to see the dim. I wish more time and resources were being spent on astronomical interferometers in the infrared and optical regions of the spectrum.
Gmr
1.7 / 5 (6) Aug 02, 2013
Umm... except that larger light gathering area equates to reduced time on target - and less smudging, potentially - so I really don't see the down side. Your increased angular resolution doesn't translate to brighter images unless a lot more time is spent staring at the same spot. []]
Requiem
2.3 / 5 (6) Aug 02, 2013
Also, as GSwift pointed out in another comment thread on the topic of a solar system-scale optical interferometer, for those spectra you must physically interfere the light from each collector at a central location to obtain the phase of the light and THEN image it, and that central location must be precisely(to within a wavelength) equidistant from all collectors.

It's a challenge which we have overcome here on Earth already, notably with the VLTi. But we can't just throw these things up and feed their data to a computer to crunch it out like we can with radio interferometers(which can measure the phase individually), it's more complicated and expensive than that.
JamesG
1 / 5 (6) Aug 02, 2013
Cool looking building. I suppose Mauna Kea is a good place for a telescope, but the future benefit of commercial space travel will make it possible to build more of these in space. THEN we will begin to really see what's out there. I hope they hurry. I'd sure like to see what they find.
GSwift7
2.3 / 5 (6) Aug 02, 2013
One thing that's paradoxical about these large telescopes is the frequency bandwidth. The mirror coating needs to be tailored to the frequency bands you're looking for. In 'visible' or near-visible light ranges you cannot go too far down the red side because the Earth's atmosphere interferes too much. You can go much deeper into in the opposite direction, UV, where the atmosphere is extremely transparent. However, due to redshift, there aren't very many objects at extreme distance that will show up brightly in UV. There are nearer objects which would be spectacular in UV, but you don't 'need' a thirty meter mirror to see them, so there aren't many big scopes looking in that wavelength. So that leaves a hole in our observations. In a sense, we are looking with more detail at objects farther away than we are at nearer objects. There may be all sorts of things to see, if you had the sharpness to see them, in our local neighborhood.
GSwift7
1 / 5 (5) Aug 02, 2013
I looked it up. There are only three space based UV telescopes currently active: Hubble, IRIS, and Swift :)

Though they spend the majority of their time in other bands, since they aren't optimized for UV. Hubble is set up for visible, IRIS is IR (duh), and swift is x-ray optimized. None of them sees best in UV. Ground based telescopes go about the same way. Everyone wants to see the stuff happening +13 billion LY away, so they do IR.
El_Nose
2.3 / 5 (3) Aug 02, 2013
almost everything built in our and future lifetimes will be the most powerful - best - strongest - fastest -- whatever superlative you want to use -- becaseu this is the first time humans have gotten technologically advanced enough to build anything
yyz
5 / 5 (3) Aug 02, 2013
"I looked it up. There are only three space based UV telescopes currently active: Hubble, IRIS, and Swift :)"

Actually there are few that weren't listed on the Wikipedia page:

The XMM-Newton Optical Monitor is a 30cm f/12.7 telescope with filters optimized for UV astronomy-

http://xmm.esac.e...ex.shtml
http://www.mssl.u.../xmm/om/

The Cassini space probe orbiting Saturn has a couple of instruments that have been utilized for (extrasolar) UV astronomy-

http://saturn.jpl...iniuvis/
http://saturn.jpl...siniiss/

Unfortunately, the recent decomissioning of the very productive GALEX UV satellite will be a loss to those studying the UV universe.
Egleton
2.8 / 5 (9) Aug 03, 2013
How refreshing. We aren't calling each other rude names.
maxb500_live_nl
2.7 / 5 (7) Aug 04, 2013
"destined to be the most advanced and powerful optical telescope in the world" Yes for about 1 year until the much larger and with greater instruments powered E-ELT comes online. Instruments of which it`s forerunners on the VLT already succeed in making VLT the most productive ground based observatory in the world. And unfortunately the TMT is still very uncertain.

E-ELT has a much higher percentage of it`s funding committed. And at actual parliament level. 300 Million from Canada in TMT? Let alone the big amounts from Japan and others? The Canadian government has not signed. TMT has to plug hundreds of millions in it`s budget. It even has to wait for that actual 250 million commitment from it`s own National Science Foundation. As we know the NSF can only pick 1 out of those 3 big US projects to help fund. That is either the Giant Magellan Telescope, the TMT or the Large Synoptic Survey Telescope. Yet the NRC has ranked the LSST as the top priority. Ouch. Far to many uncertainties.
Murius
5 / 5 (2) Aug 05, 2013
E-ELT has been greenlit! I read in a french magazine that the two telescopes will be complementary. I hope so!
alex_tudorica
5 / 5 (2) Aug 05, 2013
As other people also say, TMT won't be "the most advanced and powerful optical telescope in the world". That title belongs to the european E-ELT, which will be 1.5 times larger (in surface area). On some level, they will be complementary (TMT goes to mid-infrared while E-ELT only to near-infrared), but it's a gross exaggeration to say that one or the other will be the "most advanced" and powerful.
GSwift7
1 / 5 (5) Aug 05, 2013
Yeah, I know YYZ, but those are all quite small, which was my point. Its not that there arent UV telescopes, there just arent any big ones designed to pick up fine details at long distances. For example, the UV telescope on XXM Newton is only 12 inches in diameter. Here's an amature grade telescope of that size and type (for visible light) for under 3000 euro's:

http://www.telesk...tik.html
kevin_hingwanyu
1 / 5 (5) Aug 06, 2013
, for those spectra you must physically interfere the light from

and
and feed their data to a computer to crunch it out like we can with radio interferometers

these interferometers are novel technologies and not easy to understand, the wavelength of radio is several orders longer than visible, so does the demanding of precision shifting several orders, radio with longer wavelength reduces the costs and complexity? it has nothing to do about the symmetry (for the locations of collectors) ? Or, is it possible to build radio interferometers without maintaining symmetry (positions of collectors) compared with optical's, which supposedly computer could adjust the irregular (asymmetrical) geometry of the (locations of) collectors ? Whether it demands for absolute symmetry or not, the key factor depends on whether computer can manipulate the wave (phase/amplitude . . . etc) or not ?
kevin_hingwanyu
1 / 5 (5) Aug 06, 2013
The redshift of many mysterious objects (observed by various wavelengths? or most are near-infrared) show that some of those unknown objects are traveling at speed near c. While it is equivalent that they are located near the boundary of the (theoretically) observable universe. The coming telescopes are larger, they are going to see galaxy clusters in much deeper space, or to see 'beyond the observable' universe. It is interested to know is it possible to find objects with larger redshifts (>c) ? IF a very very large ultimate telescope finds an object, how to know if its distance is beyond the boundary of universe ? Logically the redshift determines an object's distance. The building of larger telescopes is going to answer this question. That is, to verify some of the theories in cosmology with sufficiently large telescopes.
Q-Star
1.6 / 5 (7) Aug 06, 2013
@kevin,

I'll try to help ya if I can.

The reason radio interferometry is easier to accomplish, exactly as ya say, do it's long wavelength. The longer the wave, the less scattering and distortion from photons passing through the atmosphere. But it does not give ya increased sensitivity. It gives ya greater resolving power. Spreading the collectors apart, can't increase the number of photons captured, only increase the finer degree of telling two close objects as being distinctly separate objects.

Most UV is absorbed by the atmosphere, and what's not absorbed is greatly scattered, so there is a limit as how "good" an earth based observatory can be in any UV, regardless of size or expense at our present level of technology. Even optical earth based telescopes have much to be desired at the blue end of the spectrum for just that reason. It's why the sky is a diffused blue color. Rayleigh scattering.

Infrared is also problematic because of atmospheric absorption. Will continue.
Q-Star
1.6 / 5 (7) Aug 06, 2013
The redshift of many mysterious objects (observed by various wavelengths?


There are three distinct types of redshift used in astronomical sciences.

Gravitational redshift when light passes through a strong gravitational field.

Translational redshift caused by an object's motion.

And cosmological redshift, which is the result of recessional velocity (expansion of space.) I'm thinking this the type ya are referring to. First redshift is not a measure of "speed". It's a result of space increasing. The observable universe is is a theoretically large, some say as much about 45-46 Gly. But we are constrained by the 13.7 Gy since the big bang. We can't see anything which is further away than the distance light can travel since the beginning.

At redshift z = 1000 (about 380,000 years after the beginning) we reach the limit of any kind of observation dependent on photons. Will continue.
Q-Star
1.6 / 5 (7) Aug 06, 2013
@ kevin,

Continuing,

The z number of redshift, gives a very good approximation of the the size/density of the universe for the object under consideration. Example. A galaxy at z 1.0: Ya are seeing this galaxy when the universe was z + 1 times or 2 times smaller or greater density than today. A galaxy at z 3. gives ya that object at z + 3 or a 4 times smaller or denser universe.

The CMB is at z = 1000 so at the time of recombination (380,000) the universe was 1000 times smaller, and 1000 times more dense than today. And we will never be able to see further back than that.

I hope this helps, ya seem earnest to me, so I didn't mind trying to help. (If ya trolled me, take care.)
GSwift7
1.6 / 5 (7) Aug 07, 2013
so does the demanding of precision shifting several orders, radio with longer wavelength reduces the costs and complexity?


Yes, radio is many orders of magnitude easier than visible light in terms of interferomtry. But it's still too much to crunch the numbers with a computer in order to get them to match up. They use longer or shorter wires (or fiber optic cables) to make all the signals reach the collection point at the same time. There are also active systems on each line that delay or short-cut individual signals to account for things like thermal expansion. They send something like a ping through the system to keep in in time. You could theoretically do it with computers, but the amount of number crunching would be counter-productive; you'd never be able to keep up. Ironically, this will probably never change, because the amount of data collected increases with the technology, so the data load will always outpace the power of the computers which could be used to process it
GSwift7
1.6 / 5 (7) Aug 07, 2013
If you want to understand a bit more in depth why you cannot just use a computer to combine signals from un-connected telescopes, you've gotta understand how the data is collected and how computer process and store data. Telescope data is received with massive quantities of parallel CCD's in an array. These enter the computer and are stored sequentially as individual bits at some regular frequency and stored sequentially on a disk drive. So the image is like a movie, where you get a 'frame' of information each time the CCD's cycle. If you have multiple instruments, the freqency of the CCD's on each instrument are astronomically unlikely to be synchronized to the degree needed for a computer to match the signals up. You could average them, but then you lose fidelity. Not to mention that one device will have a million CCD's and the other may have 1.2 million, so how do you match them up?
GSwift7
2 / 5 (8) Aug 07, 2013
In fact, these large telescopes gather so much data per second that it takes a dedicated supercomputer just to decode the data from one telescope, turn them into images a person can use and store them on drives. The advances in telescope technology in the past couple decades has been like the transition from bi-planes to supersonic jets in the early 20th century. Some of the newest telescopes rival mankind's greatest wonders. They really don't get the street cred they deserve. One thing that's ironic about these great achievements is that they are practically obsolete by the time they see first light.
Fleetfoot
5 / 5 (2) Aug 07, 2013
The observable universe is is a theoretically large, some say as much about 45-46 Gly. But we are constrained by the 13.7 Gy since the big bang. We can't see anything which is further away than the distance light can travel since the beginning.

At redshift z = 1000 (about 380,000 years after the beginning) we reach the limit of any kind of observation dependent on photons.


Just to tie up those numbers, the CMB was emitted from material which was about 42 million light years away. Since then, the universe has expanded by a factor of 1090 (z=1089) which means that material is 46 billion light years away now.
Fleetfoot
5 / 5 (3) Aug 07, 2013
The z number of redshift, gives a very good approximation of the the size/density of the universe for the object under consideration. Example. A galaxy at z 1.0: Ya are seeing this galaxy when the universe was z + 1 times or 2 times smaller or greater density than today.


We live in three dimensions, if sizes go down by 2, the volume goes down (and the density goes up) by 8.

The CMB is at z = 1000 so at the time of recombination (380,000) the universe was 1000 times smaller, and 1000 times more dense than today.


z=1089, the density was 1.3 billion times higher.
Q-Star
2 / 5 (8) Aug 07, 2013
The z number of redshift, gives a very good approximation of the the size/density of the universe for the object under consideration. Example. A galaxy at z 1.0: Ya are seeing this galaxy when the universe was z + 1 times or 2 times smaller or greater density than today.


We live in three dimensions, if sizes go down by 2, the volume goes down (and the density goes up) by 8.

The CMB is at z = 1000 so at the time of recombination (380,000) the universe was 1000 times smaller, and 1000 times more dense than today.


z=1089, the density was 1.3 billion times higher.


Correct indeed ya are, my goof.

@ kevin,,,,

Note this correction to my post.
rug
1.5 / 5 (8) Aug 07, 2013
@ Q-Star, GSwift, and Fleetfoot

I would like to thank you all for the in-depth descriptions. I've said before I'm not a scientist although I am very interested in space and the whole next frontier. You took very complicated things and made it understandable in just a few post. Bravo, I get the impression all three of you are in the field in some way. If not, then you guys have studied way more then I have.
kevin_hingwanyu
1 / 5 (5) Aug 08, 2013
@ Q-Star,

Atmospheric carbon dioxide and water vapour absorb/interact with infrared. Portions of atmosphere are to thermally expand or contract disturbing light or radio waves too. Spreading the energy collectors apart: That is why the expandability for resolution of radio telescopes is better than optical. And, with the number of collectors fixed same (total) energy will be distributed over larger receiving area, larger area just simply allowing more collectors to be inserted, this could maintain (received energy per total area)/pull up the brightness back to previous level. This plain scheme to expand the area of a telescope is nothing new and boring. Retain symmetry, same number of collectors may be arranged with different separations. For reflective receivers like those concave mirrors the total area do not have limit. An important question comes, for interferometer type antenna, is there a minimum (or threshold) energy needed for each collector element ?
. . .
kevin_hingwanyu
1 / 5 (5) Aug 08, 2013
. . .
That is, to observe very weak signals, if the electromagnetic energy received by an individual collector is lower than some levels, then increasing (for higher sensitivity) collectors is in vain ? I guess the reflective type don't have this problem. But building super resolution for visible spectrum is very impossible. Once increasing area/resolution retaining sensitivity, a practical super resolution for radio waves can observe extrasolar planets even their atmospheric compositions directly, and dynamically the biochemical nature, if. And even SETI. Pulsars/Neutron stars. Black hole mechanisms. Anti-matters . . . etc. Let alone to observe the edge of universe. Talking this boring super resolution is very exciting.
. . . still reading huge amount of information on wikipedia.
Q-Star
1 / 5 (5) Aug 08, 2013
. . . still reading huge amount of information on wikipedia.


That part makes sense, and I would suggest ya keep at it. Toot-a-loo.
GSwift7
2.1 / 5 (7) Aug 08, 2013
That is, to observe very weak signals, if the electromagnetic energy received by an individual collector is lower than some levels, then increasing collectors is in vain ?


That's correct. Using multiple collectors doesn't help at all if each of them isn't powerful enough to see the object by itself. An interferometer doesn't increase the brightness of the objects, it just adds fine detail, like focusing a common SLR camera lense. As with the SLR camera, if it's too dark to take the picture, then it won't matter if you're in focus or not.

I get the impression all three of you are in the field in some way


I work in the office of a big bread factory. lol. Though I did go to school for aerospace engineering, this is just a hobby for me. The trick to understanding these concepts: Google. :)
kevin_hingwanyu
1 / 5 (5) Aug 08, 2013
@ GSwift7,

They use longer or shorter wires (or fiber optic cables) to make all the signals reach the

Thanks. You explain the topics very detail. Perhaps on some documentary tv programs those computers connect to tufts of optic cables with turning several hundred rounds. These analogues saving computers' calculation time. Thermal expansion is beyond the design but adjustable. If the array has only one line of antennae, as long as those telescopes are aligned to the x-axis, e.g. they are all y=0 on the x-y plane, I guess their x-positions are rather flexible with the above analogue configurations.
kevin_hingwanyu
1 / 5 (5) Aug 08, 2013
@ GSwift7,

So the image is like a movie, where you get a 'frame' of information each time the CCD's cycle

I don't think I am going to combining signals from many telescopes with computers in these few days so my questions may not make sense. Is it easier if the observed picture is fixed/not moving/ or stay still, e.g. spend many days/nights to take deep sky pictures on films/pieces of photometric glasses, spend many days to combine the radio signals from two telescopes. Are these CCDs for optical telescopes, so interferometry for visible spectrums is preferable to do it on optical instruments directly rather than computers ?
kevin_hingwanyu
1 / 5 (5) Aug 08, 2013
@ Q-Star,

And cosmological redshift, which is the result of recessional velocity (expansion of space.) I'm thinking this the type ya are referring to

Thanks. Now I have better understanding of these topics and have some questions. After 10,000 years is it equivalent that the expansion of time of the cosmos is 10000 years ('after' 10000 years, e.g.) ? Or it is a different thing ? Telescopes (radio, optical) are larger and larger. Seeing the boundaries of universe, statistically or is it anticipate that fewer objects e.g. quasars, clusters of galaxies or unknown objects with large redshifts would be found with sufficiently large telescopes !?
Q-Star
1 / 5 (5) Aug 08, 2013
Are these CCDs for optical telescopes, so interferometry for visible spectrums is preferable to do it on optical instruments directly rather than computers ?


Uaah, kevin, I think ya are overplaying your role. NO ONE "views" through research grade telescopes with their eyes. It's all done with electronic detectors and devices, and then viewed on computers. Telescopes like we are discussing don't even have the means to look through them with your eyes.
Q-Star
1 / 5 (6) Aug 08, 2013
For any ernest viewer of this site, I am responding to ya, not the troll

Seeing the boundaries of universe,


Is impossible by any concievable physics we know of or even have pondered in abstract theory. To "see the boundaries of the universe" ya may wish to consult a religionist or a philosopher, science won't get ya there, and probably never will.
GSwift7
1 / 5 (5) Aug 09, 2013
Are these CCDs for optical telescopes, so interferometry for visible spectrums is preferable to do it on optical instruments directly rather than computers ?


Yes, Qstar is correct. There's no such thing as "long exposure" any more; not in the old sense, like with film or glass plates. Each collector now has a flat board covered with CCD's (just like in a digital camera). The longer you point at the same target, the more "movie frames" you'll get. They then need to combine all those movie frames into one picture by adding them together (not averaging). That is done with a dedicated supercomputer, usually located near the telescope, in real time. If you're doing an interferometer, with multiple collectors, then you need to perform a second layer of averaging the data from each collector, as well as adding the sequential frames together afterwards. This is never done in real time, to the best of my knowledge.
GSwift7
1 / 5 (5) Aug 09, 2013
Another interesting thing about the "images" from these big telescopes is that the "images" aren't even really in colors. The data bits are recorded on a scale of frequency and intensity, but that's just an arbitrary scale. When you decide to display it on a screen or print out a hard copy, you have to make a decision about how to translate that scale of intensity and frequency into colors, contrast, brightness, etc. It's fully adjustable and really arbitrary. You need to do quite a bit of work in order to make an image that looks like what the human eye would see by itself, since the human eye doesn't pick up all frequencies equally. So, even if you wanted to display a view of what the telescope was seeing in real time, it probably wouldn't look like anything recognizable to you. Any time you see a beautiful image on the NASA web site, you've gotta remember that someone had to spend a lot of time adjusting the colors and contrasts and brightnesses in order to make it look like that.
GSwift7
1.7 / 5 (6) Aug 09, 2013
If you're doing an interferometer, with multiple collectors, then you need to perform a second layer of averaging the data from each collector, as well as adding the sequential frames together afterwards. This is never done in real time, to the best of my knowledge


Just to be clear, that averaging I mentioned is done optically (in analogue) in most cases. When I said that this isn't done in real time, I was talking about the rare cases where they try to use computers to combine images from unconnected instruments as if they were an interferometer. This has been done a few times, but it's not common practice, and it's not how a true interferometer works.

Sorry, I didn't realize I had typed something confusing there until I went back and re-read it. You know how it is, thinking one thing, and typing another.
kevin_hingwanyu
1 / 5 (5) Aug 09, 2013
Correct indeed ya are, my goof.

@ kevin,,,,

Note this correction to my post.

@GSwift7 and @Fleetfoot Thank you. length expanded 42 m ly x z(=1089) = 46 b ly;
change in density z(=1089)^3(dimensions) = 1.29 billion times;
density, mass unchanged/volume;

Uaah, kevin, I think ya are overplaying your role. NO ONE "views" through

Scientists they look the world by interpreting the numbers output from many instruments/computers, e.g. map the CMB, pictures of sun for x-ray, infrared, contour lines showing magnetic strength on the sun. I find that the most tough part is mathematics but it can be studying. The other part the theories usually are interested. I have some ideas which sometimes I think maybe I can convert them to theories. But not sure how to submit it. The question is how to construct ideas into a theory. Another question is how to combine a theory with maths.
kevin_hingwanyu
1 / 5 (5) Aug 09, 2013
Is impossible by any concievable physics we know of or even have pondered in abstract theory. To "see the boundaries of the universe" ya may wish to consult a religionist or a philosopher, science won't get ya there, and probably never will.

The terms supernatural 'science', myths or folklore, for some events/phenomenon/topics, I wonder if one has enormous resources to investigate them then it might show that few of them might have high/strong interested statistical "non-randomness" features connected/correlated, where it could somehow reveal the nature.
kevin_hingwanyu
1 / 5 (5) Aug 09, 2013
@GSwift7,
Not to mention that one device will have a million CCD's and the other may have 1.2 million, so how do you match them up?

Two types of telescopes interferometer and concave mirror, suppose a 100m sq concave mirror. One can shield the mirror with paper then the mirror sees nothing. If the paper has many small holes on it then this reflective telescope can function now but the brightness is lower. With this configuration/feature, one can construct a similar mirror by replacing each hole with a smaller mirror. Now the 100 sq m concave mirror is replaced by those small mirrors where each small mirror has different curvature, thickness and direction. If the technology to construct those small mirrors is very perfect then it can construct 1000 sq m or larger reflective telescope. The other type of telescope interferometer how interferometry can imaging ?
GSwift7
1 / 5 (5) Aug 12, 2013
Two types of telescopes interferometer and concave mirror


An interferometer is simply two or more telescopes combined. They can be concave mirror reflector telescopes, if you like. The W M Keck telescope is an example of a concave mirror interferometer. It has two 10 meter mirrors, which can be used individually or combined as an interferometer.

The size of a segmented mirror is limited by how rigid your structure is, your ability to adjust each segment and the computer power needed to control it. As the mirror gets bigger and the number of segments increases, each of those challenges increases exponentially in difficulty. We are currently building segmented mirrors to the limit of our ability to build them.

Interferometry is different from segmented mirrors because an interferometer takes multiple images of the same thing, where each segment of a segmented mirror is looking at a different patch of sky.
yyz
5 / 5 (2) Aug 12, 2013
@GSwift7,

Speaking of the Keck interferometer, I recently read about Project OHANA, a plan born in the late 90s to combine the large optical scopes on Mauna Kea (including Keck I & II, Subaru, Gemini North & CFHT) into a single large interferometric array:

http://www.keckob...escopes/

http://www.cfht.h...spie.pdf

For a variety of reasons the plan apparently has been abandoned. In addition, the Keck interferometer was defunded/decommisioned by NASA in 2012:

http://www.skyand...093.html

Still OHANA would have been one hell of a setup if built.
GSwift7
1 / 5 (5) Aug 13, 2013
Yeah, Keck didn't really produce results that justified the expense as an interferometer. The two telescopes operating independently can do a lot more work, so I'm not bothered by that.

The same thing goes for the proposed OHANA technology. That would have tied up all those telescopes at the same time, as well as the expense of a lot of supercomputer time to process the images, for results of limited benefit. Current generation telescopes are improving fast enough without hijacking the older ones for that kind of project. There's more observing time to be done than existing telescopes can handle.

Speaking of observing time, I did manage to make it out before dawn to see the Leonids this morning. This is the first year in a long time for me that it wasn't overcast. I still only got about 45 minutes before it did become overcast, but it's better than nothing.
kevin_hingwanyu
1 / 5 (4) Aug 13, 2013
to combine the large optical scopes on Mauna Kea (including Keck I & II, Subaru, Gemini North & CFHT) into a single large interferometric array

In the map the locations of the telescopes (>3m) in the array do not form symmetric pattern. Site constraints are always there. It is possible to build the array with varied(e.g. arbitrary/irregular) altitudes and x-y locations.
kevin_hingwanyu
1 / 5 (5) Aug 13, 2013
and the computer power needed to control it. As the mirror gets bigger and the number of segments increases, each of those challenges increases exponentially in difficulty


Not to mention that one device will have a million CCD's and the other may have 1.2 million, so how do you match them up?

The construction of optical interferometer is much complicated and difficult than radio. Fiber optics seems to simplify the optical interferometry. Radio interferometers are several orders of magnitude less complicated than optical. Usually better resolving power (than optical). Radio interferometers could be enormous large. Then how radio interferometry can imaging ? How computers handling radio waves phase and amplitude (e.g. improved/enhanced resolution and intensity compared with non-interferometers(single radio antenna)) to convert it to picture pixels, just by summation and averaging ?
Q-Star
1 / 5 (4) Aug 13, 2013
to combine the large optical scopes on Mauna Kea (including Keck I & II, Subaru, Gemini North & CFHT) into a single large interferometric array

In the map the locations of the telescopes (>3m) in the array do not form symmetric pattern. Site constraints are always there. It is possible to build the array with varied(e.g. arbitrary/irregular) altitudes and x-y locations.


@ kevin,,,

Google is your friend. If ya have no idea what interferometry is, why are ya asking questions about it. FIRST read up on the basics,,,,,, THEN fashion your questions. Your questions don't have an answer, it's like: "If the orange tree doesn't bear fruit in the spring, will heavy snows in Canada in March help last year's crop?"
kevin_hingwanyu
1 / 5 (5) Aug 13, 2013
Interferometry is different from segmented mirrors

Why not insert space between each segmented mirror (for non-interferometers) ? I guess the difficulty, efforts and tech to build non-spacing segmented mirrors and the spaced segmented mirrors are no different. While inserting space can slightly increase resolving power with lower brightness. When the total area of space > total area of mirrors then it is a large segmented mirror with lower brightness.
. . ._
kevin_hingwanyu
1 / 5 (5) Aug 13, 2013
_. . .
An idea for mixed mirror comes up, has it ever existed this sort of segmented mirrors ? Here the structure, suppose a spaced segmented mirror has this configuration, it has four segments, divided into two groups A and B. A1 and A2 do what spaced segmented mirror does. B1 simulates/ghosts/phantoms/shadows/copies/repeats A1, so B2 also duplicates A2. That is, group A and group B point to the same portion of sky. Then the combination of these mirrors has both the advantages of (1) spanning larger receiving area (resolution) and (2) increasing brightness. I am not sure whether the groups A and B construct an interferometer. I speculate it (interlacing spaced segmented mirror(+ interferometer?)) works theoretically. Do you think does it work ?
Q-Star
1.7 / 5 (6) Aug 13, 2013
_Do you think does it work ?


Only if ya get Zephyr or the guy who can't drive very well to help ya with your homework.
kevin_hingwanyu
1 / 5 (5) Aug 13, 2013
@ Q-Star,
FIRST read up on the basics,,,,,, THEN fashion your questions. Your questions don't have an answer

For some answers from ya and others, now I know that my questions are very common. Others seem to have similar answers. Therefore. My speculations are not alone. The answers from ya and others are very helpful. Thank you. To google it. If I have questions may I send ya the questions for the topics interferometry and expanding universe?
Only if ya get Zephyr or the guy who can't drive very well to help ya with your homework.

Reading are my hobbies. These are my leisure time reading. I think perhaps previously I had sent questions to @cantdrive85.
Q-Star
1 / 5 (5) Aug 13, 2013
@ Q-Star,
FIRST read up on the basics,,,,,, THEN fashion your questions. Your questions don't have an answer


If I have questions may I send ya the questions for the topics interferometry and expanding universe?


Brevity is the soul of wit. I know because it says so right there. So I would rather ya didn't.

I think perhaps previously I had sent questions to @cantdrive85.


That is a GREAT idea, by all means address your questions to him. He's your go-to guy for all things astronomical. And I'm sure he would enjoy answering as many questions as ya would pose to him. He's that sort of person,,, he lives to pass on his wisdom and knowledge. And he will the first to tell ya that his understanding is miles beyond mine. I don't mind though because a man must know his limitations.
GSwift7
1 / 5 (5) Aug 15, 2013
Kevin, I agree with QStar. I think you need to read through a few wiki pages so that you can understand what is already being done and how it works, as well as what some of the terms mean. It looks like English is a second language for you, so terminology might be a barrier for you, but keep reading and you'll get it. You seem to be close to understanding this, but just missing a few simple points. QStar and I just explained it to you, but maybe you're mis-understanding some of the words? Here's a few wiki pages that will get you started:

Interferometer: http://en.wikiped...erometry

Adaptive Optics: http://en.wikiped...e_optics

Segmented Mirrors: http://en.wikiped...d_mirror

CCD (Charge-Coupled Device): https://en.wikipe...d_device

Aperture Synthesys: http://en.wikiped...ynthesis

These are the conceptes you have been talking about, without knowing what they really are. Enjoy.
kevin_hingwanyu
1 / 5 (5) Aug 22, 2013
English is not my natural language. [National Geographic,Discovery Channel] or [nasa.gov,phys.org,nature.com] styled eng I can understand it >90%, except vocabulary. But those dramas e.g. [House,Monk,Entertainment Tonight,Bloomberg Tv] the eng are difficult.

*Interferometer: Michelson-Morley experiment;
*Adaptive Optics - -in the movie with this article ;
*Segmented Mirrors - -(1)in the movie, (2)James Webb Telescope ;
*CCD: CCDs on spacecrafts of SDO (or STEREO) observe sun's uv and x-ray. The concept is that it detects shorter w-l in em spectrum. The question, what are the similar parts for radio waves?
*Aperture Synthesys: new;

, without knowing what they really are

too mess or complicated and time consuming, do not comment;

(1)don't know how to imaging with interference;
(2)Segmented Mirrors - I guess fragmented mirrors or mirrors shielded with porous paper may be used for telescopes very large(i)optical, (ii)radio telescope (antenna).