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A DART-TOF technique – zapping wood samples with superheated helium to create particulates with a chemical signature that can be measured by spectrography – allows samples to be quickly tested.

Using tools like infrared and X-ray imaging and X-ray fluorescence spectrography, they were able to more precisely date the work and explain how and where it was subsequently repainted.

It was on this basis, using sensitive spectrography that goes by the acronym Harps on a telescope in Chile, that the Geneva team concluded by 2007 that there were four planets circling the star, two of them on either side of the “habitable zone.”

Spectrography soon verified this direction not only, but gave a determination of the velocity of our motion of twelve miles per second in a direction approximately that of the constellation Lyra.

For it made long exposures possible; and only with long exposures could autographic impressions Progress in spectrography. be secured of such faint objects as nebulae, telescopic comets, and the immense majority of stars, or of the dim ranges of stellar and nebular spectra.