Webb's Gold-Plated Infrared Eye

The James Webb Space Telescope launched on 25 December 2021. It rode an Ariane 5 rocket.

It travels to a solar orbit near the Sun–Earth L2 Lagrange point. That is 1,500,000 kilometers away. Commute time: one month.

Its primary mirror spans 6.5 meters across. Eighteen hexagonal segments made of gold-plated beryllium form the surface.

Sunscreen factor of 1,000,000.

One hundred thirty-two actuation motors adjust those segments. They position the mirrors with 10 nanometer accuracy. Your optometrist lacks the actuation motors.

Webb observes wavelengths up to 28.5 micrometers. Hubble stops at 2.5 micrometers. Longer waves need bigger mirrors.

Instruments must stay below 50 K to avoid self-interference. A five-layer sunshield blocks heat. SPF 1,000,000 beats the beach.

Initial designs began in 1996 under another name. The final bill reached US$10 billion. Receipts were not kept.