Schlieren optical technique allows us to see small changes in the refractivity of air and other transparent media. Refraction due to inhomogeneity in the air is made visible by our single-mirror schlieren optics setup. The refraction can be caused by changes in the density, temperature, or pressure of the air immediately in front of the concave mirror.
Researchers at the National Institute of Standards and Technology (NIST) invented a miniature thermometer that can measure temperatures below 1 kelvin (-272.15 °C or -457.87 °F), down to 50 millikelvins (mK). The new mini-thermometer can be attached in all kinds of places to provide quick and accurate temperature measurements where needed most.