astrophysicist at the European
Space Agency, asking for in-
put. The scientist replied, but
eventually stopped respond-
ing. “It’s been very hard to get
this peer- reviewed,” he tells
the room. “Once you talk about
gravity not existing, scientists
will not talk to you.”
Knox isn’t convinced that the
Earth is definitely flat. The con-
ference marks the first time he has
met anyone in the movement in
person— including Lindberg, his
collaborator. But he does now be-
lieve, after considering Lindberg’s
and others’ experiments mea-
suring curvature, that the planet
isn’t the shape and size we’ve
been told. Knox is genuinely cu-
rious and skeptical, qualities the
movement embraces. He tells
me that scientists are doing a
poor job of explaining their work
to the public, by citing equations
and experiments the average per-
son can’t reproduce. “Everything
that proves the Earth is round is
something we cannot prove for
ourselves,” he says. “If you can’t
trust the source of all your infor-
mation, you have to go back and
get the information for yourself.”
After Knox’s presentation,
I find him at the hotel bar in a
heated discussion with a group
of young scientists and students
who bought tickets to the con-
vention on a whim. They thought
it might be fun to observe flat-
Earthers. If they got bored, they
figured, they could go skiing.
One of the men, Ian Wessen,
has an undergraduate degree in
physics. He is locked in a debate
with Knox about his theory of
discidial force. Wessen suggests
that they do an experiment:
Submerge a cork in a bucket
of water and hold it to the bot-
tom, then release the cork while
dropping the bucket. They place
bets on what will happen to the
cork before the bucket hits the
POPSCI.COM • FALL 2019 7979Asking questions underpins all of
science—and certain anti- science
conspiracies. Proponents of a disc-
shaped planet try to cast doubt on
complex but robust facts about the
physical world and put forward their
own theoretical alternatives. Here,
we answer some popular lines of flat
Earth inquiry. —Eleanor CumminsQ: Why can you see a city
on a distant shore?
A: Our eyes see objects when light
reflects off a surface, like a build-
ing facade. The beams try to travel
in straight lines, but the curvature
of the planet can limit their visi-
bility over the horizon. This bulge
means a 6-foot-tall person can see
only about 3 miles. But the tops
of tall objects like Chicago’s Wil-
lis Tower peek above the vista; a
boater cruising on Lake Michigan
can glimpse the upper floors.Q: Why is it so difficult
to find a nonstop flight
between two cities in the
Southern Hemisphere?
A: The lower half of the planet hap-
pens to have much less landmass
than its northern counterpart. Now-
adays, fuel-efficient planes make
a direct path between, say, Austra-
lia and Chile routine. But the routes
aren’t exactly popular. Ninety per-
cent of Earth’s population lives in
the Northern Hemisphere, securing
its cities as major transit hubs.Q: Why do nations share
control of Antarctica?
A: The short answer: science di-
plomacy. The 12 signatories of the
1959 Antarctic Treaty decided
that no nation’s claim to the frostycontinent would be approved
or rejected. Instead, the land
would serve as a shared space for
research, free from permanent
settlements and the pressures of
economic development. That’s
why the ice sheet appears drunk-
enly divided like a Thanksgiving
pie, and some countries (such as
Argentina, Chile, and the United
Kingdom) have overlapping claims.Q: Why are NASA images
of Earth composites?
A: Most satellites orbit closer
to Earth than you’d think. The
International Space Station, for
example, circles just 254 miles
above us. At this height, astronauts
aboard can see the curvature of the
planet, but not the whole thing all
at once (even from the moon, only
one side of the globe is visible). To
create a more comprehensive and
higher-resolution image of the
blue marble, space cameras take
a series of photos and stitch them
together, much like the panorama
setting on your smartphone.Q: What if gravity didn’t
really exist?
A: If someone turned off gravity,
you’d fly to the ceiling of whatever
room you’re in—until the whole
building detached from the ground.
Objects of mass exert the invisible
force upon each other; it’s why ap-
ples fall toward Earth’s core, and
why Earth orbits its sun. Without
gravity holding things together, the
planet would eventually break apart
and float away. The cosmos would
not fare much better: Every thing
in the universe would eventually
become a featureless soup.