TITLE: Asteroid probe snaps rare images of Martian Moon
March 13, 2025 3:29 PM
By Agence France-Press
Paris -
On the way to investigate the scene of a historic asteroid
collision, a European spacecraft swung by Mars and
captured rare images of the red planet's mysterious small
moon Deimos, the European Space Agency said
Thursday.
Europe's HERA mission is aiming to find out how much of
an impact a NASA spacecraft made when it deliberately
smashed into an asteroid in 2022 in the first test of our
planetary defenses.
But HERA will not reach the asteroid - which is 11 million
kilometers from Earth in the asteroid belt between Mars
and Jupiter - until late 2026.
On the long voyage there, the spacecraft swung around
Mars on Wednesday.
The spacecraft used the planet's gravity to get a "kick" that
also changed its direction and saved fuel, mission analyst
Pablo Munoz told a press conference.
For an hour, HERA flew as close as 5,600 kilometers from
the Martian surface, at a speed of 33,480 kilometers an
hour.
It used the opportunity to test some of its scientific
instruments, snapping around 600 pictures, including rare
ones of Deimos.
The lumpy, 12.5-kilometer-wide moon is the smaller and
less well-known of the two moons of Mars.
Exactly how Deimos and the bigger Phobos were formed
remains a matter of debate.
Some scientists believe they were once asteroids that
were captured in the gravity of Mars, while others think they could have been shot from a massive impact on the
surface.
The new images add "another piece of the puzzle" to
efforts to determine their origin, Marcel Popescu of the
Astronomical Institute of the Romanian Academy said.
There are hopes that data from HERA's "HyperScout" and
thermal infrared imagers which observe colors beyond
the limits of the human eye - will shed light on this mystery
by discovering more about the moon's composition.
Those infrared imagers are why the red planet appears
blue in some of the photos.
Next, HERA will turn its focus back to asteroid Dimorphos.
When NASA's DART mission smashed into Dimorphos in
2022, it shortened the 160-meter-wide asteroid's orbit
around its big brother Didymos by 33 minutes.
Although Dimorphos itself posed no threat to Earth, HERA
intends to discover whether this technique could be an
effective way for Earth to defend itself against possibly
existence-threatening asteroids in the future.
Space agencies have been working to ramp up Earth's
planetary defences, monitoring for potential threats so they
can be dealt with as soon as possible.
Earlier this year, a newly discovered asteroid capable of
destroying a city was briefly given a more than 3% chance
of hitting Earth in 2032.
However further observations sent the chances of a direct
hit back down to nearly zero.
Richard Moissl, head of the ESA's planetary defense
office, said that asteroid, 2024 YR, followed a pattern that
will become more common.
As we get better at scanning the skies, "we will discover
asteroids at a higher rate," he said.
The ESA is developing a secondary planetary defense
mission to observe the 350-meter-wide asteroid Apophis,
which will fly just 32,000 kilometers from Earth on April 13,
2029.
If approved by the ESA's ministerial council, the Ramses
mission will launch in 2028, reaching the asteroid two
months before it approaches Earth.