Scientists have been searching for 40 years.
Atomic oxygen was first detected in Mars’ atmosphere back in the 1970s. However, it has remained elusive since. Now, thanks to an instrument onboard the Stratospheric Observatory for Infrared Astronomy (SOFIA), oxygen has finally been detected again.
The atoms were found in the upper layers on the Martian atmosphere, known as the mesosphere. It turns out atomic oxygen affects how other gases escape Mars, which in turn has a significant effect on the planet’s atmosphere. Therefore, the discovery could help astronomers determine how gases escaped from the Martian atmosphere so long ago.
To NASA’s surprise, they detected about half the amount of oxygen expected, but this may be due to variations in the Martian atmosphere. So scientists will continue to use SOFIA to study these differences.
"Atomic oxygen in the Martian atmosphere is notoriously difficult to measure," said Pamela Marcum, SOFIA project scientist, in a NASA press release. "To observe the far-infrared wavelengths needed to detect atomic oxygen, researchers must be above the majority of Earth’s atmosphere and use highly sensitive instruments, in this case a spectrometer. SOFIA provides both capabilities.”
Since Earth’s atmosphere is so dense and moist, it’s extremely difficult to see the universe outside of it. And even though SOFIA, a giant Boeing 747SP jetliner, is located 13.7 kilometers (45,000 feet) above Earth’s surface, it still has to be equipped with a large, 100-inch diameter telescope that can soar above most of the Earth’s atmosphere to get a clear picture.
Luckily, with this high vantage point, coupled with specialized equipment that ignores Earth’s atmosphere, the team was able to make their calculations.
So far, NASA has not given any exact figures on how much atomic oxygen was found in the Martian mesosphere, but they did say it was lower than expected. For now, we will have to wait for the results, but no matter what, they are sure to be exciting.
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