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.