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Longer sentences, more descriptive words (about B1)

Longer sentences, more descriptive words (about B1)

NASA's Perseverance Rover Pictures Earth Behind Mars' Moon

NASA's Perseverance rover photographed Earth and the Martian moon Phobos.
NASA's Perseverance rover photographed Earth and the Martian moon Phobos.

NASA's Perseverance rover has captured a special moment on Mars. On July 2, the rover took pictures of Earth moving behind Phobos, which is the largest moon of Mars. This was the first time that humans recorded Earth disappearing behind another world's moon.

Composite sequence: Earth appears as a point of light as Phobos passes in front of it.
Composite sequence: Earth appears as a point of light as Phobos passes in front of it.

The rover used its Mastcam-Z camera system in Jezero Crater to take a series of photos. During this event, Earth was about 195 million miles away, so it appeared as a single tiny pixel. Meanwhile, Phobos was orbiting 4,850 miles above the Martian surface.

Scientists call this type of event an occultation because a larger object covers a smaller one behind it. Taking these photographs was not easy. The team needed precise timing because Phobos orbits Mars three times every day while Earth stays visible for longer periods.

Why do you think scientists spend so much time taking photographs of space events?

Adapted from NASA Solar System.

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