It is often said that a picture is worth a thousand words, and the first images from the James Webb Space Telescope did not disappoint.
During a July 12 news conference, the world had a ringside seat to the most remarkable images of the universe ever taken.
Over the hour, five images left us wanting more. This is only the tip of the cosmic iceberg.
The deep-field image (above) showed thousands of galaxies, including a few that look stretched. This is not a flaw of the telescope. It is the distortion caused by gravity from a foreground large galaxy.
Einstein predicted this warping, or curvature, of the fabric of space-time, much like someone standing on a trampoline where the mat is distorted. The larger the object, the bigger the distortion of light.
To show the power of James Webb, the area of space where the deep-field image was taken was as small as a grain of sand held at arm’s length. This cluster is located 4.6 billion light-years away. That is the amount of time it took the light to reach us from back when our sun and planets were slowly being created from the solar nebula.
Launched on December 25, 2021, the mighty Ariane 5 rocket delivered the seven-ton James Webb Space Telescope into space, where it was deployed and gracefully continued its journey. It travelled for another 30 days, to its final position (known as Lagrange 2), a point in space some 1.5 million kilometres from Earth (or about four times the Earth-moon distance).
Unlike the Hubble Space Telescope—which was launched in 1990 with a flawed mirror requiring a repair mission in 1993 outfitting it with corrective lenses—James Webb is too far for a service mission. Who knows if there will be such a mission down the road if needed, but for now, there are no plans to ever visit the telescope.
The $10-billion project is a collaboration between NASA, the European Space Agency, and the Canadian Space Agency, along with private companies. Canada’s contribution is the Fine Guidance Sensor (FGS), used to point the massive telescope as well as the Near-Infrared Imager and Slitless Spectrograph (NIRISS).
Thousands of people worldwide worked on this project, which began in 1996. Then, it was called the Next Generation Telescope. In 2002, the name was changed to James Webb Space Telescope, after the man who was NASA's administrator from 1961 to 1968. These were the early days of the Mercury, Gemini, and, especially, Apollo space programs.
The Webb project suffered redesign setbacks along the way (and the COVID-19 pandemic did not help matters). When completed, the 18 gold-plated six-sided honeycomb-style mirrors measured a total width of 6.5 metres, compared to Hubble’s 2.4-metre single mirror. This results in more light-gathering power along with its infrared capability to observe heat signatures through clouds of interstellar dust.
Another critical part of the telescope is the sun shield, measuring the size of a tennis court. Comprised of lightweight material with special thermal properties, the five layers will provide a shield from the sun’s heat and light—as well as the heat of its own instruments allowing the sensitive infrared to work without interference. The mirror will operate at -223 degrees Celcius and the rest of the equipment at close to absolute zero, or -273 degrees Celsius.
The James Webb Space Telescope has opened a news portal to discovery. In the wise words of Carl Sagan, “Somewhere, something incredible is waiting to be known.”
Will we someday glimpse the first stars and infant galaxies dating back 13.8 billion years, to the Big Bang that started our universe? Only time will tell.
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2022-07-20 00:22:22Z
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