NASA InSight Mars mission to land Monday, probe the planet’s interior

An illustration of NASA’s
InSight probe attempting to land on the surface of
Mars

Lockheed
Martin/YouTube

• NASA will try to land its InSight probe on the surface
  of the red planet around 3 p.m. ET on Monday.
• The robotic lander must survive “seven minutes of
  terror” before touching down and beginning a series of
  unprecedented scientific firsts.
• InSight won’t move around Mars, but it could be the first mission to
  measure the “vital signs” of the planet and decode its internal
  structure.
• NASA will also listen for
  “marsquakes” caused by meteorite impacts and tectonic
  movements, which could reveal the interior structure of the
  4.6-billion-year-old world.

On Cyber Monday, while online shoppers hunt for deals, NASA will
be trying to stick its first landing of a robot on the surface of
Mars in six years.

The roughly $830-million mission is called InSight,
which is short for “Interior Exploration using Seismic
Investigations, Geodesy and Heat Transport.”

NASA
rocketed the InSight probe toward the red planet on May 5.
The lander, which weighs about 789 lbs, is expected to complete a
risky descent sequence around 3 p.m. ET on Monday, November 26.
Part of that process is known as the “seven minutes of terror.”

If all goes well, the golf-cart-size lander will be the first
robot to touch down on Martian soil since NASA’s
nuclear-powered Curiosity rover, which landed there in August
2012.

Read more: 13
incredible facts you probably didn’t know about the red
planet

Scientists hope that InSight’s two-year mission will probe Mars
in ways they’ve only dreamed of until now.

“All of our past missions have really been surface missions,”
Robert Braun, NASA’s former
chief technologist, told Business Insider. “InSight’s a very
different mission in the sense that it is peering into the past
by studying, really, the interior of Mars. In doing so, we’re
going to learn about Mars, but also about the early history of
the Earth.”

First, however, InSight will have to get safely to the surface.

How InSight might survive ‘7 minutes of terror’

An illustration of NASA’s
InSight Mars probe in the “seven minutes of terror” phase of its
descent to the Martian surface.

NASA/JPL-Caltech

Getting to Mars is relatively easy.

That’s because modern rockets are safer and more reliable to
launch than ever before. In fact, the vehicle that sent InSight
toward Mars — an Atlas V rocket built by United Launch Alliance —
has had only one partial failure since its debut in 2002.

Landing on the red planet, however, is one of the most
challenging tasks an aerospace engineer can accomplish. About a
third of robots sent there never make it.

“Although we’ve done it before, landing on Mars is hard, and this
mission is no different,” Rob Manning, the chief engineer at
NASA’s Jet Propulsion Laboratory, said in a video. “It takes thousands of steps to go
from the top of the atmosphere to the surface, and each one of
them has to work perfectly.”

The Martian
atmosphere is about 1% as thick as Earth’s. But that’s still
plenty of air to completely destroy a spacecraft like InSight,
which will be moving at about 12,500 mph when it arrives at the
red planet.

NASA tries to take advantage of the Martian atmosphere by putting
its robots in an entry capsule with a heat shield. This helps
reduce the spacecraft’s speed while also protecting it from
1,400-degree-Celsius temperatures — hot enough to melt steel —
caused by plowing through the thin Martian air.

An animation of NASA’s
InSight probe attempting to land on the surface of
Mars.

Lockheed
Martin/YouTube

However, striking the atmosphere at anything other than the
perfect angle — about 12 degrees, Manning said — can end a
mission. Any shallower than this, and an entry capsule will
“skip” off the atmosphere and out into deep space. Any deeper,
and a robot gets vaporized.

This phase — when an entry capsule detaches from its mothership
and descends — is sometimes called the seven minutes of terror.
This is because NASA can’t “hear” from its spacecraft for roughly
seven minutes, and won’t know if a landing has succeeded or
failed until a radio signal arrives (or doesn’t).

This time around, though, NASA is trying something new: It sent
two briefcase-size satellites called MarsCubeOne with Insight.
Both cubesats are
trailing the lander en route to Mars, and they’ll help relay
landing data home.

“They’ll be broadcasting that back to Earth so we know what’s
exactly happening at each step of the entry, descent, and landing
process,” Tom Hoffman, the InSight mission’s payload
manager, said during a press briefing in October.

An engineer tests the
solar arrays of NASA’s Mars Cube One satellite, or
MarCO.

NASA/JPL-Caltech

Once InSight plows through enough of the Martian atmosphere to
not burn up, its entry capsule will deploy a big supersonic
parachute, then discard the heat shield seconds later.

InSight’s dangerous journey isn’t over at this point. The robot
still has to deploy three landing legs and use radar to calculate
how close it is to the ground — NASA can’t control the robot
remotely in real time because it takes light (and radio signals)
about 15 minutes to travel to and from Mars.

About a mile above the surface of Mars, InSight will drop out of
its protective capsule, fire its retro-rocket engines, and try to
touch down without crashing or tipping over.

How InSight will probe the ancient secrets of Mars — and Earth

A cutaway illustration
showing what scientists think the interior of planet Mars might
look like.

NASA/JPL

InSight will try to land in a region known as Elysium Planitia, which is a
relatively flat place close to the Martian equator. If the robot
safely lands and unfurls its two circular solar panels, NASA will
begin its mission in earnest.

Like InSight’s nearly identical predecessor mission, the Phoenix
Mars Lander, the probe won’t move locations. But unlike Phoenix,
which dug for water in Martian soil for a few months in 2008,
InSight hopes to last for two Earth years.

During that time, it will perform the first “checkup” of the 4.6-billion-year-old
planet.

“InSight’s goal is to study the interior of Mars and take the
planet’s vital signs, its pulse, and temperature,” NASA said on
its mission website. “To look deep into Mars, the
lander must be at a place where it can stay still and quiet for
its entire mission. That’s why scientists chose Elysium Planitia
as InSight’s home.”

NASA
plans to land its InSight robot at Elysium Planitia near the
Martian equator.

NASA;
Business Insider

Once InSight is powered up and in communication with Earth, one
of its first tasks will be to unfurl a robotic arm.

InSight will use that robotic appendage to place a dome down on
the Martian surface. The dome will contain six extremely
sensitive vibration-detection devices called seismometers.

Seismometers on the Earth and the moon (Apollo
astronauts deployed some on the lunar surface) have recorded
earthquakes and moonquakes, which helped scientists figure out
the internal structure of those rocky worlds. On Mars, NASA
researchers hope to accomplish a similar feat.

Whenever a meteorite strikes Mars, or there’s a landslide, or a
big blob of magma suddenly shifts, or there’s tectonic movement,
InSight’s seismometer should detect such vibrations. The devices
can even record seismic activity from all the way across the
planet.

Over time, data about marsquakes could reveal hitherto unknown
information about the internal structure of the planet.

One of the most challenging tasks InSight will attempt, though,
is drilling a heat probe deep into the ground. The probe will
slowly drill down and stop every so often to heat up. Then a
sensor will detect how long it takes that warmth to dissipate.

An
artist illustration of the InSight lander on
Mars.
NASA/JPL-Caltech

The probe is expected to dig 16 feet down — far deeper than any
previous Mars mission has ever reached with scoops, shovels, or
drills.

“When we get down that deep, we’ll get away from all of the
temperature variations of the surface,” Suzanne Smrekar, the
mission’s deputy principle investigator, said during a press
briefing. “That tells us about the heat coming out of the planet
— that energy that’s available for driving geologic activity.”

Back on the surface, InSight will also use a sensitive radio
science experiment to see how subtly Mars shifts during its
two-Earth-year-long orbit around the sun. Such data should tell
researchers what is going on in the deepest parts of the planet’s
core.

The
lead scientists on the InSight mission to Mars, Bruce Banerdt,
speaks during a press conference on October 31,
2018.

NASA/Bill
Ingalls

The ultimate goal is to figure out how Mars formed and what
happened to the planet since then. Scientists know that Mars once
generated an atmosphere-protecting magnetic dynamo, as Earth
still does today. But the Martian core’s dynamo eventually shut
down and the planet’s protective shield faded, which allowed the
sun to
blow away Mars’ atmosphere and
oceans of water.

In probing that history, scientists think we’re bound to learn
about our own planet’s origins.

“Earth … is a big planet that holds a lot of heat, a lot of
energy, and it’s been very geologically active over its entire
history. So most of the record of the early processes that formed
the Earth have been erased,” Hoffman said. “We’d like to have a
planet that’s just a little bit calmer and that can retain that
that evidence.”

Mars, which is similar to Earth but has remained almost frozen in
time, is thus the perfect place to go looking.