A new study from the University of Toronto Scarborough suggests that search for life on planets outside our solar system may be more difficult than previously thought.
The study, authored by a team of international researchers led by UTSC Assistant Professor Hanno Rein from the Department of Physical and Environmental Science, finds the method used to detect biosignatures on such planets, known as exoplanets, can produce a false positive result.
The presence of multiple chemicals such as methane and oxygen in an exoplanet's atmosphere is considered an example of a biosignature, or evidence of past or present life. Rein's team discovered that a lifeless planet with a lifeless moon can mimic the same results as a planet with a biosignature.
"You wouldn't be able to distinguish between them because they are so far away that you would see both in one spectrum," Rein said.
The resolution needed to properly identify a genuine biosignature from a false positive would be impossible to obtain even with telescopes available in the foreseeable future, Rein asserted.
"A telescope would need to be unrealistically large, something one hundred metres in size and it would have to be built in space," he said.
"This telescope does not exist, and there are no plans to build one any time soon," he added.