Venus has a carbon dioxide atmosphere of 90 atmospheres on the ground and a surface temperature of 460 ° C, so it has been considered that the possibility of life is low.On the other hand, the possibility of the presence of microorganisms at an altitude of around 50 km, where both atmospheric pressure and temperature drop, has been partially investigated.

　This time, when I observed Venus with a radio wave with a wavelength of about 1 mm using the James Clerk Maxwell telescope (Hawaii), I found a sign of hydrogen phosphate.Furthermore, hydrogen phosphate was detected by observation with the ALMA telescope (Chile, South America) (the ratio of existence is about 10 per 20 billion atmospheric molecules).In order to investigate the origin of hydrogen phosphate, we examined the chemical reaction of the Venusian atmosphere by sunlight and lightning, trace elements blown up by the wind from the surface of the earth, and supply by volcanic gas. I concluded that only hydrogen can be produced.

　On the other hand, there are microorganisms on the earth that extract phosphorus from rocks and other biological substances, add hydrogen, and discharge it as hydrogen phosphate.The researchers believe that the detected amount of hydrogen phosphate can be explained if similar microorganisms are present in the Venusian atmosphere.

　The research team believes that the existence of life cannot be confirmed only by detecting hydrogen phosphate.However, since hydrogen phosphate is a molecule that is considered to be one of the indicators of biosignature on extrasolar planets, this discovery is a very important material for verifying its validity, and it will be used in the future. It is said that it shows the importance of detailed observation of the Venusian atmosphere.

Paper information:[Nature astronomy] Phosphine Gas in the Cloud Decks of Venus