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A new study suggests Jupiter’s icy moon (卫星) Europa produces much less oxygen than previously thought. The study was based on the data 【小题1】 (collect) by NASA’s Juno spacecraft.
The study involved Juno’s instruments measuring levels of oxygen 【小题2】 hydrogen molecules (分子) coming from Europa’s atmosphere. The data showed the icy moon produces about 1,000 tons of oxygen every 24 hours. NASA said that would be enough amount 【小题3】 (keep) a million humans breathing for a day.
However, the space agency noted those estimates of oxygen were much less than those measured in earlier studies about the moon. Europa is a little 【小题4】 (small) than the Earth’s moon. But it is still one of the largest moons in 【小题5】 (we) solar system. NASA observations have suggested 【小题6】 ocean exists beneath the thick layer of ice on Europa’s surface. Scientists estimate the moon’s ocean may contain a large amount of water, 【小题7】 is twice as the Earth’s oceans.
Since Europa was believed to have a large ocean under its surface, 【小题8】 (researcher) in the past identified it as a good candidate to hold the right conditions to support some form of life. That data came 【小题9】 (main) from telescope observations of oxygen levels existing in the moon’s icy surface. The new lower estimates of oxygen do not support the earlier observations. The team involved in the study said, in the future, more research 【小题10】 (need) to confirm the latest findings.
