BBC Knowledge Asia Edition

Fitness tracker made

from used chewing gum

THEY DID WHAT?!

For the first time, astronomers
have detected magnetic fields
near the event horizon of
Sagittarius A*, the black hole
that lies at the centre of our
Galaxy.
“These magnetic fields have
been predicted to exist, but no
one has seen them before. Our
data puts decades of theoretical
work on solid observational
ground,” said Principal
Investigator Shep Doeleman,

the Assistant Director of MIT’s

Haystack Observatory.

The presence of the fields

was revealed using the Event

Horizon Telescope (EHT)

• a global network of radio
  telescopes that function as one
  giant scope the size of Earth.
  The EHT team detected the
  magnetic fields by measuring
  the linear polarisation of the
  light emitted by Sagittarius A*.
  The polarised light is emitted

by electrons spiralling around

magnetic field lines and so

directly traces the structure of

the magnetic field.

“With this result, the EHT

team is one step closer to

solving a central paradox in

astronomy: why are black holes

so bright [if their gravitational

pull is so great they can draw in

light]?” said Doeleman.

This groundbreaking

observation was made possible

thanks to the remarkable

resolution a telescope the size

of the EHT offers. It is hoped,

however, that more radio dishes

from around the world will be

added to the EHT’s network

enabling it to gather even more

astronmical data. More data will

allow the EHT’s astronomers

to achieve greater resolution,

possibly enough to directly

image a black hole’s event

horizon for the first time.

SPACE

Magnetic field

at event horizon

spotted

Lines of polarised light

trace the shape and

orientation of the magnetic

fields around Sagittarius A*

What did they do?

A team at the University of Manitoba

embedded a solution of carbon

nanotubes into a piece of chewing

gum that had been chewed for 30

minutes and left overnight.

Urgh! What did they find?

Believe it or not the strange concoction

resulted in a highly sensitive flexible

sensor capable of recording movements

such as human head turning and finger

bending. It could also detect changes in

humidity, potentially making it capable

of monitoring changes in breathing.

Why did they do that?

They were searching for a flexible

material to use as a miniature sensor

that could be used in biochips and

bodily motion sensors.