This article is the product of the scientific journalism school that took place at MIPT on 25-30 November 2010
Author: MIPT student Oleg Feya
Infrared heterodyne spectrometer is a very useful device. Physicists of the Space Research Institute of the Russian Academy of Sciences are planning to use it to determine the wind speed and wind direction on other planets. This was announced at the 53rd MIPT Scientific Conference, where the report "Heterodyne Infrared Spectrometer" was presented, explains Informnauka.
Spectroscopy can remotely determine the characteristics of the material based on the characteristics of its emission spectrum (in this case - in the infrared range). You can use it to study the gas composition of the atmosphere of another planet. Heterodyne spectrometer also has its own radiation generator and allows you to compare the spectra of extraterrestrial gases to pre-defined spectra of the same substances. The reference signal obtained from stationary gas may be different from the signal received from space, due to the Doppler effect – the change of the properties of electromagnetic radiation because of the movement of its source. Thus, based on the degree of difference of the spectrum of a reference gas to the reference spectrum, you can calculate the characteristics of the movement of the gas, that is, the wind.
The development of a new spectrometer is headed by a senior research fellow of the Space Research Institute Alexander Rodin. The project involves professionals and students of the Moscow Institute of Physics and Technology (MIPT), and the Moscow State Pedagogical University. Development is carried out in the framework of grants allocated to MIPT as a national research university. Participants of the project, MIPT students Oleg Benderov and Artem Klimchuk, spoke about the current results at the 53rd MIPT Scientific Conference.
Alexander Rodin’s idea is to create an infrared spectrometer, operating at a wavelength of 3.3 microns. It is there where strong emission lines of methane, nitrous oxide, and many isotopes found in the atmospheres of the terrestrial planets (Mars, Venus) and Jupiter can be observed. Previously, spectrometers were almost never used to create models of the circulation of the atmospheres of these planets. Foreign heterodyne spectrometers used by NASA and the European Union work on a wavelength of about 10 microns, which is convenient for studying the atmospheres of different gas compositions. For example, with their help scientists built a model of the circulation of ethane in the atmosphere of Saturn's moon, Titan.
Another advantage of the short-wavelength spectrometer is its compactness. It does not use interferometers that take up a lot of space (devices used to separate the wave flow into separate beams and to create interference patterns), without which foreign higher wavelength spectrometers cannot operate. This means that the new spectrometer can be used on spacecraft. In addition, the absence of the interferometer makes setting up the device easier.
The device uses new radiation detectors. The superconducting single-photon detector of niobium nitrite, which was designed by Moscow State Pedagogical University employee Gregory Goltzman, allows you to record a photon hit of very small power, which is important in the case of weak radiation sources.
Now scientists have created a test sample - device working at a wavelength of 1.5 microns. In the coming months, the developers plan to bring all parameters to the planned ones, as well as connect a telescope to the device, which will turn it into a full spectrometer.
Source: report "Heterodyne Infrared Spectrometer" at the 53rd MPT Scientific Conference. Speakers: Oleg Benderov and Artem Klimchuk.