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For anyone else like me that wasn't sure what ATA stood for, this is not the ATA hardware attachment interface. ATA here is Allen Telescope Array: https://en.m.

For anyone else like me that wasn't sure what ATA stood for, this is not the ATA hardware attachment interface. ATA here is Allen Telescope Array: https://en.m.wikipedia.org/wiki/Allen_Telescope_Array https://en.m.wikipedia.org/wiki/Allen_Telescope_Array

ncmncm 5y ago
Today I learned a new non-SI unit, the Jansky, abbreviated Jy, a measure of energy flux "equivalent to 10^−26 watts per square metre per hertz". Can somebody explain why it is interesting to get a much-lower resolution image than the VLA provided? Is it sampling some property the VLA image does not? (E.g., 8+ GHz samples higher-energy processes.) Or is this an exercise in technique (one person doing the work of an institute?), or in extracting usable data from antennas not built for the purpose? Background and motivation would be helpful. [Edit:] The previous paper is helpful: "Here we show a complete description of the interferometric pipeline, covering from the IQ output of the SDRs to the CLEAN images. Therefore, this experiment is a valuable resource for anyone interested in learning about interferometry in radio astronomy."
- CamperBob2 5y ago
  Aside from the educational value, they're showing they can get 10% of the VLA's image quality with 0.0001% of the budget. That's not an inconsiderable achievement.
  - ncmncm 5y ago
    I guess that is covered under "an exercise in technique (one person doing the work of an institute?)". Thanks.
- rahen 5y ago
  > Can somebody explain why it is interesting to get a much-lower resolution image than the VLA provided? Is it sampling some property the VLA image does not? The ATA has less and shorter baselines, each made of much smaller collecting elements than the (E)VLA. Put simply, baselines bring resolution, collecting area brings sensitivity, and both are intricate (the longer the baseline, the more sensitivity you need). Have a look also at VLBA techniques, which allow for even higher resolutions. Such a technique was used with the EHT to "image" the M87 blackhole.
- jdporter 5y ago
  Why do you say it's a non-SI unit? Seems to me it is. I mean, it's a derived unit, not a fundamental unit; but still SI.
  - ncmncm 5y ago
    I only quoted the Wikipedia page saying so. The component units are SI, but the 10^-26 factor looks arbitrary.
TacticalCoder 5y ago
Thanks, somehow with the headline I was thinking about imagining the old Cygnus text editor running on a PC boosted at 8.45 Ghz and was intrigued but wasn't too sure what ATA had to do with it!
- coverband 5y ago
  I similarly was thinking that this was about imaging an older Cyrus CPU…

ncmncm 5y ago

Today I learned a new non-SI unit, the Jansky, abbreviated Jy, a measure of energy flux "equivalent to 10^−26 watts per square metre per hertz". Can somebody explain why it is interesting to get a much-lower resolution image than the VLA provided? Is it sampling some property the VLA image does not? (E.g., 8+ GHz samples higher-energy processes.) Or is this an exercise in technique (one person doing the work of an institute?), or in extracting usable data from antennas not built for the purpose? Background and motivation would be helpful. [Edit:] The previous paper is helpful: "Here we show a complete description of the interferometric pipeline, covering from the IQ output of the SDRs to the CLEAN images. Therefore, this experiment is a valuable resource for anyone interested in learning about interferometry in radio astronomy."

CamperBob2 5y ago
Aside from the educational value, they're showing they can get 10% of the VLA's image quality with 0.0001% of the budget. That's not an inconsiderable achievement.
- ncmncm 5y ago
  I guess that is covered under "an exercise in technique (one person doing the work of an institute?)". Thanks.
rahen 5y ago
> Can somebody explain why it is interesting to get a much-lower resolution image than the VLA provided? Is it sampling some property the VLA image does not? The ATA has less and shorter baselines, each made of much smaller collecting elements than the (E)VLA. Put simply, baselines bring resolution, collecting area brings sensitivity, and both are intricate (the longer the baseline, the more sensitivity you need). Have a look also at VLBA techniques, which allow for even higher resolutions. Such a technique was used with the EHT to "image" the M87 blackhole.
jdporter 5y ago
Why do you say it's a non-SI unit? Seems to me it is. I mean, it's a derived unit, not a fundamental unit; but still SI.
- ncmncm 5y ago
  I only quoted the Wikipedia page saying so. The component units are SI, but the 10^-26 factor looks arbitrary.

TacticalCoder 5y ago

Thanks, somehow with the headline I was thinking about imagining the old Cygnus text editor running on a PC boosted at 8.45 Ghz and was intrigued but wasn't too sure what ATA had to do with it!

coverband 5y ago
I similarly was thinking that this was about imaging an older Cyrus CPU…