Russian physicists suggest using a heterodyne infra-red range spectrometer for measuring speed and direction of winds on other planets.

Spectroscopy allows using emission spectrum of a substance (in infra-red range, in this case) for remote determination of its characteristics. This technique can help study gas composition of atmospheres of other planets. A heterodyne spectrometer has its own radiation generator, which can help compare spectra of gases, originating on other planets, with predetermined spectra of same substances. A reference signal of a stationary gas can be different from a signal, which arrived from space, due to Doppler effect – change in properties of electromagnetic radiation, caused by its source’s movement. Therefore, difference of a space gas spectrum from a reference spectrum allow calculating characteristics of gas movement, in other words, a wind.

A scientific group, working on construction of a new spectrometer, consists of research fellows from the Institute of Space Research, students of Moscow Institute of Physics and Technology (which graduates Konstantin Novoselov and Andre Geim earned the Nobel Prize in Physics in 2010) and Moscow State Pedagogical University.

The idea is building an infra-red spectrometer, which works on a wavelength of 3.3 microns. But why such a wavelength has been chosen by the researchers? The wavelength of 3.3 micrometer provides strong emission lines of methane, nitrous oxide, and many isotopes, common for atmospheres of earth-type planets (Mars, Venus) and Jupiter as well. In the past spectrometers have been extremely rarely used for building models of atmospheric circulations of mentioned planets. Foreign heterodyne spectrometers, working for NASA and European Union, use waves with length of about 10 micrometers, which are convenient for studying atmospheres with gas composition, differing from Earth’s atmosphere. These research facilities helped scientists to create a model of ethane circulation on Titan, a Saturn’s moon.

Another great feature of a short-wave spectrometer is its size – the facility is small due to not using large interferometers (devices for dividing wave flows into separate beams and creating interference patterns), which are an essential part of foreign spectrometers, working with larger wavelengths. This means the new spectrometer can become a part of a spaceship. Moreover, absence of an interferometer makes device’s adjustment much simpler.

Other notable parts of the spectrometer are new radiation detectors – a superconducting single-photon detector, made of columbium nitrite by a scientist from Moscow State Pedagogical University, can detect extremely weak photons, which is important in case of working with weak radiation sources.

Researchers have already built a prototype spectrometer, working of a wavelength of 1.5 micrometers, and are currently testing it. Plans for next several months are bringing the device’s parameters to design parameters and combining it with a telescope, which turns the device into a full-scale spectrometer.