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Can this technology be used for a new type hubble?

Thomas1016 said:
Can this lense described in the link below be used to buuild a new type of hubble telescope?

http://physicsweb.org/articles/news/9/4/12
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No. Metamaterials as described and theorized have negative index of refraction only in relatively narrow wavelength bands.

One of the great advantages -- in fact one of the major science requirements -- of Hubble-class astronomical telescopes is the ability to view objects over a wide range of wavelengths, almost always several octaves. (HST observes from near UV to the IR). An astronomical telescope using the metamaterials as we know them today would be severely crippled by limiting its abilities to small fractions of the wavelength ranges of conventional optics.
 
Timothy said:
No. Metamaterials as described and theorized have negative index of refraction only in relatively narrow wavelength bands.

One of the great advantages -- in fact one of the major science requirements -- of Hubble-class astronomical telescopes is the ability to view objects over a wide range of wavelengths, almost always several octaves. (HST observes from near UV to the IR). An astronomical telescope using the metamaterials as we know them today would be severely crippled by limiting its abilities to small fractions of the wavelength ranges of conventional optics.
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Thread-killer.:rolleyes:
 
Timothy said:
No. Metamaterials as described and theorized have negative index of refraction only in relatively narrow wavelength bands.

One of the great advantages -- in fact one of the major science requirements -- of Hubble-class astronomical telescopes is the ability to view objects over a wide range of wavelengths, almost always several octaves. (HST observes from near UV to the IR). An astronomical telescope using the metamaterials as we know them today would be severely crippled by limiting its abilities to small fractions of the wavelength ranges of conventional optics.
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More like yes, but no, but maybe.

The HST does indeed view objects across a wide range of wavelengths, but not all with the same detector. It uses separate detectors for IR, visible, and UV. One of the instruments is multi-spectral by nature, the Space Telescope Imaging Spectrograph.

However, all of those instruments share the same optics. This saves a lot of money. A design like the current HST would not be possible with these new materials. These new 'lenses' can only focus at a narrow range of wavelengths.

However, if we abandon the use of a single optic path for every detector, and instead use a separate optic path for each, we could use the new 'lens' materials.
 
GodMark2 said:
More like yes, but no, but maybe.

The HST does indeed view objects across a wide range of wavelengths, but not all with the same detector. It uses separate detectors for IR, visible, and UV. One of the instruments is multi-spectral by nature, the Space Telescope Imaging Spectrograph.

However, all of those instruments share the same optics. This saves a lot of money. A design like the current HST would not be possible with these new materials. These new 'lenses' can only focus at a narrow range of wavelengths.

However, if we abandon the use of a single optic path for every detector, and instead use a separate optic path for each, we could use the new 'lens' materials.
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All of the instruments are multispectral, each with dozens of filters. And the simplification that separate detectors are used for the UV, the visible, and the IR mistakenly gives the impression that there are separate detectors that each cover those specific ranges. The complement of detectors in the instruments cover bands that span the spectrum (UV-vis, vis-IR, and various subsets, depending on science requirements).

A single detector channel can have a very wide wavelength range. The three detectors on NICMOS span .8 to 2.5 microns. Compare that to a metamaterial where the negative index is on the order of 50-100 nm, not to mention the dispersion. (I was trying to answer the OP as simply as possible. The next problem would be the same as using standard refractive optics over a wide wavelength range, chromatic aberration and the transparency of the metamaterial at the wavelength of interest.)

Saving money is not the driver for using a common path for the OTA, it's aperture. You waste throughput if you dice up the available aperture for separate paths for dozens of narrowband systems.

I'm not saying that a metamaterial can't be used somewhere in a space telescope. But the OP's question pointed to "can this cool new material be used instead of what Hubble did to make it way better?" The answer is no.
 
Most of Timothy's post I agree with, as it depends on a difference in interpretation of the broadness of the term in the OP "new type of Hubble".

However:
Timothy said:
Saving money is not the driver for using a common path for the OTA, it's aperture. You waste throughput if you dice up the available aperture for separate paths for dozens of narrowband systems.
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Contains an error (possibly an error in understanding my statement about saving money). Specifically, if money were of no concern, we could have a separate full aperature for each instrument package, with no need to "dice up the available aperture for separate paths for dozens of narrowband systems". The sattelite would be coresponding larger, or we would have more than one sattelite. By making only one path, we save all the costs for those extra optic paths, AND allow the full aperature for each instrument. One of Hubble's greatest strengths is it ability to field such a wide aray of diffraction limited instruments for such a small price.

Metamaterial's greatest strength is to remove diffraction limits. We'd swap price for resolution.
--GodMark2
 
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