What’s onboard the James Webb space telescope

Science instrument module (ISIM)

Houses all cameras and science instruments

Stabilising

trim-flap

Star-tracking

telescopes

Solar power

Steering and

control bus

Antenna for sending

data and receiving

commands from Nasa

Secondary mirror

Reflects light from primary mirror to the science instruments

Primary mirror

18 hexagonal segments made of beryllium and coated in gold to capture feint infrared light

-233C

Cold side

85C

Hot side

Heat shield

5 layers protect optical instruments from light and heat from the sun

1.8m person

to scale

Science instrument

module (ISIM)

Houses all cameras and

science instruments

Stabilising

trim-flap

Solar power

Star-tracking

telescopes

Steering and

control bus

Antenna for sending

data and receiving

commands from Nasa

Primary mirror

18 hexagonal segments made of beryllium and coated in gold to capture feint infrared light

Secondary mirror

Reflects light from primary mirror to the science instruments

-233C

Cold side

85C

Hot side

Heat shield

5 layers protect optical instruments from light and heat from the sun

1.8m person

to scale

Science instrument

module (ISIM)

Houses all cameras and

science instruments

Stabilising

trim-flap

Star-tracking

telescopes

Solar power

Antenna for sending

data and receiving

commands from Nasa

Steering and

control bus

Secondary mirror

Reflects light from primary mirror to the science instruments

Primary mirror

18 hexagonal segments made of beryllium and coated in gold to capture feint infrared light

-233C

Cold side

85C

Hot side

Heat shield

5 layers protect optical instruments from light and heat from the sun

1.8m person

to scale

-233C

Cold side

Science instrument

module (ISIM)

Houses all cameras and

science instruments

85C

Hot side

Heat shield

5 layers protect optical

instruments from light

and heat from the sun

Star-tracking

telescopes

Solar power array

Steering and

control bus

Antenna for sending

data and receiving

commands from Nasa

Stabilising

trim-flap

Primary mirror

18 hexagonal segments made

of beryllium and coated in gold

to capture feint infrared light

Hubble

primary mirror

2.4m diameter

JWST

primary mirror

6.5m diameter

Secondary

mirror

Reflects light from

primary mirror to the

science instruments

1.8m person

to scale