1st-ever close-up photo of Mars' moon Deimos reveals the Red Planet's violent past

Deimos, a moon of Mars, is formed of the same stuff as the Red Planet itself, according to a satellite from the United Arab Emirates, suggesting an earlier collision.

One of Mars' two tiny moons, Deimos, has recently been shown in a startling new image by the United Arab Emirates' Martian orbiter Hope. The observations from a flyby on March 10 show that Deimos is made of the same materials as Mars itself, suggesting the moon formed at the same time as Mars and isn't a captured asteroid, as some theories have proposed. These findings were presented at the European Geosciences Union meeting this week.

These observations showed a view of Mars and Deimos that had never been seen previously.

Mission leader Hessa Al Matroushi of the Mohammed Bin Rashid Space Centre in Dubai told Nature.com that Mars was in the backdrop, which was "just mind-blowing, honestly."

For decades, humans have been studying Mars, but most of our rovers have kept close to the planet's surface. Deimos is tidally locked to Mars, which means that the same side constantly faces the planet. As a result, until Hope came, probes approaching Mars could only observe one side of the small moon.

Hope, formerly known as the Emirates Mars Mission (EMM), launched in the middle of 2020 and landed on Mars in the first half of 2021. The primary purpose of EMM, the first interplanetary spacecraft from an Arab country, was to study changes in the Martian atmosphere. After the probe finished its original mission, the EMM team made the decision to use the spare fuel that was still on board to raise the spacecraft's orbit over Deimos. This move allowed the researchers to get the first-ever detailed images of the far side of the Martian moon.

The small moon, which is just 7.7 miles (12.4 kilometers) across, or roughly half the length of Manhattan, New York, was seen in images from Hope's first flyby of Deimos in a variety of wavelengths, from ultraviolet to infrared. Deimos had similarities across wavelengths, suggesting that it is made of Mars-like material rather than the typical carbon-rich material seen in asteroids.

Al Matroushi said, "If there were carbon or organics, we would notice spikes in particular wavelengths.

This is unexpected because Deimos was frequently thought of be a captive asteroid by astronomers. Instead, it appears to be a piece of Mars itself, maybe snipped off in a previous impact. As a result of a similar impact, the moon of Earth is believed to have formed billions of years ago, possibly giving our planet another another thing in common with its rocky red neighbor.