He started working at
Texas Instruments in 1961, where one of his early projects was the development of a low-temperature thermometer that was developed using a
germanium semiconductor that had been
doped with small quantities of
gallium, which measured changes in temperature based on the change in the device's electrical resistance as energy was absorbed. Based on his academic experiences, he came to the conclusion that the technology behind this thermometer could be integrated as the basis for a bolometer that could be used to measure the
radiant energy coming from stars as
infrared radiation, waves that occupy a portion of the electromagnetic spectrum whose wavelength is longer than for visible light (400–700 nm), but shorter than those of
terahertz radiation (100 μm – 1 mm) or
microwaves. Low was named to serve as facility scientist for NASA's Space Infrared Telescope Facility, later renamed the
Spitzer Space Telescope. The effort had been delayed by cost overruns, until Low had an inspiration at a 1993 retreat for the project's scientists; the passive cooling technique could be used – rather than place the entire telescope in a bath of
liquid helium to cool the unit to temperatures near
absolute zero, the unit could be exposed to the vacuum of space to radiate most of its heat while the detectors themselves were the only components cooled using liquid helium, a design change that allowed the Spitzer project to go ahead towards its launch in 2003.
Timothy Hawarden has been recognized by NASA for the development of the passive cooling technique, which has also been included in other space probes, such as the
James Webb Space Telescope, a partial successor to the
Hubble Space Telescope, that will search for the oldest objects in the universe. ==Personal==