4 ms·

As a spectroscopist I appreciate how excrementally hard these measurements are to make. Also as a spectroscopist, I look at the error bars (especially as wavel

As a spectroscopist I appreciate how excrementally hard these measurements are to make. Also as a spectroscopist, I look at the error bars (especially as wavelength increases) and wonder how they make the assignments. (Yes, I did read the paper)

spullara 3y ago
excrementally? like, hard as shit?
- OldGuyInTheClub 3y ago
  I was inspired by https://getyarn.io/yarn-clip/98ba61b7-99c5-4a6b-b49e-a0e6f3932423 https://getyarn.io/yarn-clip/98ba61b7-99c5-4a6b-b49e-a0e6f39...
jonhohle 3y ago
> excrementally hard Sounds terrible.
photonbeam 3y ago
> excrementally I’ll be looking for ways to use this in casual conversation
- OldGuyInTheClub 3y ago
  John Cleese has a use case. Please see the link to getyarn.io below (assuming post order stays constant of course)
- mikepurvis 3y ago
  My assumption is that Cleese's use is an intentionally comedic corruption of "execrably", but given his pedigree it's probably now considered the King's English.
  - OldGuyInTheClub 3y ago
    I thought he was slipping something past the censors. He uses a different epithet in this live performance. https://www.youtube.com/watch?v=uT3OQECSDoQ https://www.youtube.com/watch?v=uT3OQECSDoQ
defrost 3y ago
> and wonder how they make the assignments. Worth looking into, ie: request their raw data and crawl over their numerics. The paper suggests a lot of 5 sigma et al rejections and iterative rolling medians, etc. all of which is all very fine save oft times in the execution via hand rolled exquisitely crafted one off filters that can converge and produce results even if "wrong" (off by one binning errors, etc. etc. etc...). I'm not saying they're wrong, I am saying (as you likely know) it's easy to make small mistakes that can reinforce noise into signal.
- OldGuyInTheClub 3y ago
  > Worth looking into, ie: request their raw data and crawl over their numerics. I didn't say I was a good spectroscopist. ;-P I kid, I kid. On the one hand, a planet crosses its star. A craptillion miles away, JWST captures the starlight passing through a sliver of atmosphere and spectrally resolves it to whatever degree it can through multiple instruments. That's just incredible. On the other hand, qualitative chemical analysis of gas mixtures is hard enough with high spectral resolution and these are low resolution spectra. Gas phase lineshapes in lab spectra can be Lorentzian, Gaussian, or usually Voigt (convolution of Lorentzian and Gaussian.) Teasing out the fits usually requires not just high resolution but very high SNR especially in the wings: https://cefrc.princeton.edu/sites/g/files/toruqf1071/files/Files/2013%20Lecture%20Notes/Hanson/pLecture6.pdf https://cefrc.princeton.edu/sites/g/files/toruqf1071/files/F... Not only are the authors claiming to identify silicates but nanoparticles of quartz vs. other silicates and/or oxides using broad spectral bins and with big error bars. I just don't see how they get there no matter how much they "torture the data." Having seen a few of these recent spectral announcements, I have to wonder what's really going on. JWST was conceptualized in the late 1980s before exoplanets were even found. AFAIR, it was going to be a "First Light Machine." Then as exoplanets became important and the JWST program ran into trouble, it feels like the exoplanetary characterization became integral to keeping the program sold. Slide 26 of this presentation by exoplaneteers even states a goal: "Reclaim JWST from cosmologists – Win more than our fair share with a goal of capturing 25% of mission time" https://exoplanets.nasa.gov/exep/files/exep/4%20Beichman.pdf https://exoplanets.nasa.gov/exep/files/exep/4%20Beichman.pdf JWST is a magnificent beast but even at 6.5m, it can only collect so much and stare for so long. It feels like it is a pathfinder that will set requirements for future exoplanet-specific missions.
mnky9800n 3y ago
I always enjoyed the irony of combining spectroscopy with astronomy for exactly this reason.

spullara 3y ago

excrementally? like, hard as shit?

OldGuyInTheClub 3y ago
I was inspired by https://getyarn.io/yarn-clip/98ba61b7-99c5-4a6b-b49e-a0e6f3932423 https://getyarn.io/yarn-clip/98ba61b7-99c5-4a6b-b49e-a0e6f39...

jonhohle 3y ago

> excrementally hard Sounds terrible.

photonbeam 3y ago

> excrementally I’ll be looking for ways to use this in casual conversation

OldGuyInTheClub 3y ago
John Cleese has a use case. Please see the link to getyarn.io below (assuming post order stays constant of course)
mikepurvis 3y ago
My assumption is that Cleese's use is an intentionally comedic corruption of "execrably", but given his pedigree it's probably now considered the King's English.
- OldGuyInTheClub 3y ago
  I thought he was slipping something past the censors. He uses a different epithet in this live performance. https://www.youtube.com/watch?v=uT3OQECSDoQ https://www.youtube.com/watch?v=uT3OQECSDoQ

defrost 3y ago

> and wonder how they make the assignments. Worth looking into, ie: request their raw data and crawl over their numerics. The paper suggests a lot of 5 sigma et al rejections and iterative rolling medians, etc. all of which is all very fine save oft times in the execution via hand rolled exquisitely crafted one off filters that can converge and produce results even if "wrong" (off by one binning errors, etc. etc. etc...). I'm not saying they're wrong, I am saying (as you likely know) it's easy to make small mistakes that can reinforce noise into signal.

OldGuyInTheClub 3y ago
> Worth looking into, ie: request their raw data and crawl over their numerics. I didn't say I was a good spectroscopist. ;-P I kid, I kid. On the one hand, a planet crosses its star. A craptillion miles away, JWST captures the starlight passing through a sliver of atmosphere and spectrally resolves it to whatever degree it can through multiple instruments. That's just incredible. On the other hand, qualitative chemical analysis of gas mixtures is hard enough with high spectral resolution and these are low resolution spectra. Gas phase lineshapes in lab spectra can be Lorentzian, Gaussian, or usually Voigt (convolution of Lorentzian and Gaussian.) Teasing out the fits usually requires not just high resolution but very high SNR especially in the wings: https://cefrc.princeton.edu/sites/g/files/toruqf1071/files/Files/2013%20Lecture%20Notes/Hanson/pLecture6.pdf https://cefrc.princeton.edu/sites/g/files/toruqf1071/files/F... Not only are the authors claiming to identify silicates but nanoparticles of quartz vs. other silicates and/or oxides using broad spectral bins and with big error bars. I just don't see how they get there no matter how much they "torture the data." Having seen a few of these recent spectral announcements, I have to wonder what's really going on. JWST was conceptualized in the late 1980s before exoplanets were even found. AFAIR, it was going to be a "First Light Machine." Then as exoplanets became important and the JWST program ran into trouble, it feels like the exoplanetary characterization became integral to keeping the program sold. Slide 26 of this presentation by exoplaneteers even states a goal: "Reclaim JWST from cosmologists – Win more than our fair share with a goal of capturing 25% of mission time" https://exoplanets.nasa.gov/exep/files/exep/4%20Beichman.pdf https://exoplanets.nasa.gov/exep/files/exep/4%20Beichman.pdf JWST is a magnificent beast but even at 6.5m, it can only collect so much and stare for so long. It feels like it is a pathfinder that will set requirements for future exoplanet-specific missions.

mnky9800n 3y ago

I always enjoyed the irony of combining spectroscopy with astronomy for exactly this reason.