20 ASTRONOMY • OCTOBER 2019
Dreaming deep
Planetary scientist Bruce Banerdt, the
mission’s principal investigator, has been
studying the formation and evolution of
Mars and other planets at Caltech’s Jet
Propulsion Laboratory (JPL) since 1983.
For decades, he and scores of other plan-
etary geophysicists from around the
world have been thinking about ways
to learn whether Mars is dead or alive.
They knew that seismology — the
study of earthquakes and related phe-
nomena — was the key to understanding
Earth’s interior. But to do similar research
on Mars meant that they’d have to figure
out how to build and deploy seismometers
and other geophysical sensors that could
handle the stresses of a launch from Earth
and the harsh environment of Mars’ sur-
face. And they knew that it wouldn’t be
possible to deploy a global network of
thousands of seismometers like we have
on our planet. At best, they could contem-
plate setting up a small network of at least
a few seismometers and other instru-
ments, like the Apollo astronauts had
done at six landing sites on the Moon,
using spacecraft similar to those that had
already successfully landed on Mars. At
worst, they could deploy only one.
And indeed, one it would have to be.
The costs, complexity, and risks ofattempting multiple landings on Mars
simply didn’t fit within the constraints of
NASA’s “faster, better, cheaper” Discovery
program line, and no larger-class mis-
sions to study martian geophysics were
scheduled for the foreseeable future. So,
Banerdt began lining up a team to make
the best possible pitch to NASA for a mis-
sion to study Mars’ interior.
To reduce risk, the team proposed to
leverage JPL’s experience in designing
and operating Mars surface missions,
and to use essentially the same Lockheed
Martin lander that had successfully car-
ried the Phoenix mission’s experiments
to the surface in 2008. And to reduce
cost, the team relied on space agencies
from other countries to contribute a
major percentage of the instruments.
This rather gutsy decision would comeIs Mars a dead world like the Moon,
or an active, living terrestrial planet like Earth?
That’s the $830 million question that an
international team of scientists and engineers
are trying to answer with the latest robotic
inhabitant of the Red Planet. NASA selected
the InSight mission in 2012 from a pool of
nearly 30 proposals for exploring the solar
system that had been submitted to the space
agency’s Discovery program competition two
years earlier. InSight — short for “Interior
Exploration using Seismic Investigations,
Geodesy, and Heat Transport” — is, as the
name implies, a mission designed to study
the deep interior of Mars from the vantage
point of a single station on the surface.
An Atlas V rocket carrying NASA’s InSight spacecraft rises above a fog bank
shortly after launch from Vandenberg Air Force Base in California the morning
of May 4, 2018. NASA/CORY HUSTONInSight captured this panorama of its landing site December 9, 2018, the 14th martian day (sol) of its planned
two-year mission. This 290°-wide field of view comprises 30 individual images and shows the rim of the
degraded crater the spacecraft landed in, nicknamed Homestead Hollow.