– OUT OF THIS WORLD –
• The James Webb Space Telescope (JWST) is an orbiting infrared observatory and the world’s most powerful telescope.
• Launched on Dec. 25, 2021, it successfully disengaged from the rocket that carried it into space; deployed its solar panels; traveled at 524 mph (843 kph) for a month for nearly a million miles (four times the distance of the Moon); and unfurled its mirrors and sunshield, all without a hitch.
• JWST orbits in the L2 Lagrange point, named for a mathematician who lived in the 1700s. Lagrange points are spots where the gravitational push-and-pull of two bodies, in this case the Sun and Earth, equalize. They are used by spacecraft to reduce fuel consumption needed to remain in position.
• Now in position, JWST is able to capture light that’s been traveling across space for up to 13.5 billion years, when the first stars and galaxies were formed. It is so sensitive it can detect the heat signature of a bumblebee at the distance of the Moon, and can see details the size of a penny at a distance of 25 miles (40 km).
• To preserve Webb’s heat-sensitive equipment, it has a ‘sunshield’ that’s the size of a tennis court which gives the telescope the equivalent of SPF protection of 1 million. The difference in temperature between the hot side and the cold side of the sunshield is nearly 600 F. (315 C).
• James Webb’s mirrors are the lightest large telescope mirrors ever made. They are constructed of beryllium, a metal which resists expanding and contracting during temperature changes. Each of the 18 mirrors is coated with a layer of pure gold so thin that a human hair is 1,000 times thicker. Then they are coated with a protective layer of silicon dioxide glass.
• The JWST is 100 times more powerful than the 30-year-old Hubble Space Telescope.
• While Hubble’s mirror stood at 7.8 ft (2.4 m) in diameter, the James Webb telescope’s mirror has the diameter of 21.3 feet (6.4 m), allowing it to capture six times more light than Hubble. While being much larger than Hubble, the James Webb weighs in at about 14,000 lbs. (6,350 kg) which is about half as much as Hubble.
• With Hubble, scientists were able to peek into galaxies that formed 400 million years after the Big Bang , but JWST can look back to just 250 million years after the Big Bang, and perhaps even earlier.
• Hubble collects images in mostly ultraviolet (visible) light, while James Webb collects infrared light, just beyond the visible spectrum. This reveals more detail about the objects in those images. The JWST can see right through massive clouds of dust that limit the view of visible-light observatories like Hubble. These dusty nebulas are where stars and planetary systems form.
• Over the course of Hubble’s life, five space shuttle crews made service calls to correct the telescope’s problems, but Hubble is only 340 miles (547 km) away, while the James Webb is 930,000,000 miles away, far beyond the reach of any repair crew. However, if the proper technology is developed, scientists could someday send a robot to refuel it, extending its life.
• The telescope is fueled by 240 liters of hydrazine fuel and dinitrogen tetroxide oxidizer, which is used to keep itself in the correct position and orient the mirrors to any particular point in the universe. It’s expected that the fuel will run out in about ten years. Yet, designers included a refueling port where a nozzle from some future space robot might be used to give it a second chance.
