Primary mirror diameter6.5 m
6.09Baseball bats
4.3 tenthsYacht lengths
18 hexagonal gold-coated beryllium segments
Photo from Wikimedia Commons
James Webb Space Telescope
The most powerful space telescope ever launched/Spacecraft
Launched on Christmas Day 2021, the James Webb Space Telescope orbits the Sun at the L2 Lagrange point, 1.5 million kilometers from Earth. Its 6.5-meter gold-coated beryllium mirror collects infrared light from the earliest galaxies in the universe. A tennis-court-sized sunshield keeps the instruments at a frosty 50 Kelvin. It cost $10 billion and took 25 years to build, making it both the most expensive and most overdue telescope in history.
Measurements
Total mass6,500 kg
2.6 billionMosquito weights
86.7Keanu Reeveses
About 6.5 tonnes at launch
Sunshield area300 m²
1,875Pizza box tops
10.8Studio apartments
Roughly the size of a tennis court
Operating temperature50 K
1.6 tenthsHuman fevers
2.8 hundredthsMolten steel pours
2.4 tenthsMars surface temps
Cold side of sunshield; -223°C
Sunshield length21.2 m
2.1 tenthsCity block lengths
26.5 millionthsFlorida lengths
Sunshield width14.2 m
158French fry lengths
2.8 billioniPhone transistors
946,667White blood cells
Primary mirror area25.4 m²
540iPad screens
6.9 tenthsTwo-car garages
13.7Standard doors
Collecting area; 6× larger than Hubble
Distance from Earth1.5 billion m
15.5 billionSoftball circumferences
12.5 quadrillionCoronaviruses
60 quadrillionRibosomes
1.5 million km at L2 Lagrange point