During the previous four years, Mars experienced quakes and a meteorite
slammed into the planet. NASA's InSight lander captured soundwaves that
helped unveil mysteries of the Martian interior.
During these incidents, InSight discovered seismic waves moving into the
Martian core for the first time. Researchers have now discovered that Mars
has a liquid iron-alloy core that also contains lighter elements like sulfur
and oxygen, as well as tiny quantities of hydrogen and carbon.
Scientists can gain a better knowledge of Mars' interior by studying how
rocky planets like Earth and Mars develop, how they vary from one another,
and what makes other planets hospitable for life.
In the Monday issue of the journal Proceedings of the
National Academy of Sciences, a research outlining the results was released.
According to research coauthor Vedran Lekic, associate professor of geology
at the University of Maryland, College Park, "scientists first discovered
the Earth's core by observing how seismic waves from earthquakes were
affected by traveling through it in 1906." "More than a century later, we're
using what we know about seismic waves on Mars. With InSight, we're finally
learning what Mars' core is like and what separates it from Earth while also
making it comparable.
Researchers calculated the density and chemical composition of the Martian
core by measuring the time it took seismic waves produced by a single
marsquake and a meteorite strike to pass through the core.
Planetary core provides information on evolution
The Martian core appears to be totally formed of liquid, unlike Earth's,
which has a solid inner core and a liquid outer core. Mars' core has a
radius of around 1,106 to 1125 miles (1,780 to 1,810 kilometers), and it is
also somewhat denser and smaller than scientists had anticipated.
"You can think of it this way; the properties of a planet's core can serve
as a summary about how the planet formed and how it evolved dynamically over
time," research coauthor Nicholas Schmerr, associate professor of geology at
the University of Maryland, College Park, said in a statement.
The production of life-sustaining circumstances or their absence might be
the outcome of the formation and evolution processes. Due to the
peculiarities of the Earth's core, it may produce a magnetic field that
shields us from solar winds and keeps water in the atmosphere. Because Mars'
core does not provide this barrier, the planet's surface is inhospitable to
life.
Although there isn't a magnetic field on Mars right now, there are still
signs of magnetism in the planet's crust. According to the findings, Mars
formerly sustained a climate that may have been livable before changing
through time to become an uninhabitable frozen desert.
In some respects, it's like a puzzle, according to Lekic. "For instance,
the core of Mars contains minute amounts of hydrogen. In other words, there
had to be some circumstances in which the hydrogen could have existed, and
we need to comprehend those circumstances in order to comprehend how Mars
changed through time to become the planet it is today.
The initial plan was for the InSight mission, the first to investigate
Mars' innards, to endure for only around two years. However, NASA decided to
prolong the mission by two more years.
"The extra mission time certainly paid off," said Dr. Jessica Irving,
senior lecturer in Earth sciences at the University of Bristol in the United
Kingdom, who is the principal author of the research.
"We have recorded the first evidence of seismic waves moving through Mars's
core. We have been able to investigate the Martian core using seismic waves
thanks to two seismic signals—one from a very far-off marsquake and the
other from a meteorite impact on the opposite side of the planet. Now that
we've heard it, we've been listening for energy moving through the center of
another planet.
When dust prevented the InSight project's solar panels from receiving the
requisite sunlight in December 2022, the mission came to an end and became
quiet. However, the wealth of information the lander gathered over its four
years on the surface of Mars has altered how scientists think about the
planet.
For many years to come, InSight will continue to have an impact on how we
comprehend the genesis and development of Mars and other planets, according
to Lekic.
