Study: Venus’ atmosphere too dry for life
The uncertainty of science: A new study has found that the amount of water in Venus’ atmosphere is too low to support the possibility of life.
On Earth, Hallsworth said, microorganisms can survive and proliferate in droplets of water in the atmosphere when temperatures allow. However, the findings of the new study, based on data from several Venus probes, leave zero chance of anything living in the clouds of Venus, he said.
“Living systems including microorganisms are composed mainly of water and without being hydrated, they can’t be active and are unable to proliferate,” Hallsworth said.
Studies on microorganisms living in extreme conditions on Earth found that life can exist at temperatures as cold as minus 40 degrees Fahrenheit (minus 40 degrees Celsius). For water activity, which is measured on the scale from 0 to 1, the lowest survivable value is 0.585. The water activity level found in the molecules in the Venusian clouds was merely 0.004.
NASA Ames astrobiologist Chris McKay, one of the co-authors of the paper, said in the news conference that the findings of the study were conclusive and the new fleet of space missions currently being prepared for Venus will not change anything about the hope for life on Earth’s closest neighbor.
McKay can be as “conclusive” as he wants, but that really isn’t how science works. While this data is very strong evidence that there is no life on Venus, a result that should be expected given its harsh environment, it can’t preclude for certain the possibility. You can’t prove a negative in science.
At the same time, this paper puts another nail in the coffin of that very weak result, since found even weaker, in September 2020 that suggested the presence of phosphine in the atmosphere that suggested the possibility of life.
The uncertainty of science: A new study has found that the amount of water in Venus’ atmosphere is too low to support the possibility of life.
On Earth, Hallsworth said, microorganisms can survive and proliferate in droplets of water in the atmosphere when temperatures allow. However, the findings of the new study, based on data from several Venus probes, leave zero chance of anything living in the clouds of Venus, he said.
“Living systems including microorganisms are composed mainly of water and without being hydrated, they can’t be active and are unable to proliferate,” Hallsworth said.
Studies on microorganisms living in extreme conditions on Earth found that life can exist at temperatures as cold as minus 40 degrees Fahrenheit (minus 40 degrees Celsius). For water activity, which is measured on the scale from 0 to 1, the lowest survivable value is 0.585. The water activity level found in the molecules in the Venusian clouds was merely 0.004.
NASA Ames astrobiologist Chris McKay, one of the co-authors of the paper, said in the news conference that the findings of the study were conclusive and the new fleet of space missions currently being prepared for Venus will not change anything about the hope for life on Earth’s closest neighbor.
McKay can be as “conclusive” as he wants, but that really isn’t how science works. While this data is very strong evidence that there is no life on Venus, a result that should be expected given its harsh environment, it can’t preclude for certain the possibility. You can’t prove a negative in science.
At the same time, this paper puts another nail in the coffin of that very weak result, since found even weaker, in September 2020 that suggested the presence of phosphine in the atmosphere that suggested the possibility of life.