2019-04-01_Astronomy

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10 ASTRONOMY • APRIL 2019

The newest addition to the martian

probe family has safely arrived,

and it’s wasting no time getting

familiar with the area.

fter enduring almost seven months of

space travel on a carefully calculated

300 million-mile (480 million kilo-

meters) journey from Earth to Mars,

NASA’s InSight lander finally touched

down on the martian surface November 26,

2018. Equipped with a host of cutting-edge
      scientific instruments, the lander is
      expected to gather some of the best data yet
      on the Red Planet’s interior, composition,
      and tectonic activity.
      InSight — which stands for Interior
      Exploration using Seismic Investigations,
      Geodesy and Heat Transport — entered the
      martian atmosphere 80 miles (129 km)
      above the surface. At an altitude of about
      7 miles (11 km), the probe deployed its giant
      parachute to help reduce speed. Less than a
      minute later, InSight cut its parachute free
      and fired its 12 retrorockets, providing the
      craft with the extra braking power it needed
      to neatly settle onto the planet’s surface at
      2:54 P. M. EST.

A tense landing

The entire landing took only about seven

minutes, but because of an eight-minute

delay in communications between Mars

and Earth, NASA engineers were forced

to wait until the landing was over to know

whether it was successful. So, from the

time the craft entered Mars’ atmosphere

until touchdown, those involved (as well

as those not) anxiously crossed their fin-

gers, oblivious to the real-time status of

the craft. During these well-known “seven

minutes of terror,” the engineers waited for

confirmation that the probe had landed

safely — which, thankfully, it did.

“It was intense, and you could feel the

emotion,” said NASA Administrator Jim

Bridenstine in a NASA livestream about the

landing’s success. But that tension quickly

INSIGHT SETS UP

SHOP ON MARS

shifted to excitement once InSight landed.

“The enthusiasm here is incredible,”

Bridenstine said.

Settling in

InSight’s first few days on the Red Planet

weren’t as eventful as the probe’s nerve-

wracking descent and landing, but the

craft has been adjusting to Mars well. On

December 11, engineers directed InSight to

take its first selfie. This allowed the team to

survey the sand-filled crater it had landed in,

which so far seems to be a near-ideal location.

On December 15, the mission team com-

manded InSight to test its claw-game-like,

five-fingered grapple by delicately lifting the

lander’s seismometer. By December 19, the

instrument, which will monitor marsquakes

to study the planet’s interior structure, had

been safely placed on the ground about 5 feet

(1.6 meters) in front of the lander.

“It’s taken more than a decade to bring

InSight from a concept to a spacecraft

approaching Mars — and even longer

since I was first inspired to try to under-

take this kind of mission,” said InSight’s

principal investigator Bruce Banerdt, of

the Jet Propulsion Laboratory, in a press

release. “But even after landing, we’ll need

to be patient for the science to begin.”

— Chelsea Gohd, Jake Parks

SEIS SET. InSight deploys its

Seismic Experiment for Interior

Structure (SEIS) on the martian

surface, just weeks after landing

on the planet. Although InSight

is equipped with a suite of

instruments, SEIS is the most

vital to achieving the lander’s

core science objectives.

EARTH: THE NOT-SO-WATERY WORLD

JUST A SPLASH. Roughly 70

percent of Earth’s surface is covered

by water, which, at face value, seems

like a lot. But did you know that

liquid water accounts for only about

0.12 percent of Earth’s total volume?

Our planet, which we often think of

as a water world, is actually pretty

desiccated. However, many other

worlds in the solar system are

figuratively drowning in water,

making them intriguing targets for

future exploration and study. — J.P.

FAST

FAC T

Ice accounts for less

than 2 percent of

Earth’s total water.

But on Enceladus, ice

accounts for about

70 percent of the

world’s total water.

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