Supertelescópio James Webb vai ser lançado
December 18, 2021 - O Telescópio Espacial James Webb, o maior e mais poderoso observatório alguma vez construído, vai ser lançado a bordo de um foguetão Ariane 5 do porto espacial europeu ma Guiana Francesa. Uma vez em órbita, vai permitir aos astrónomos observar os recônditos mais longínquos do universo.
Conceived 30 years ago as the successor to the Hubble Space Telescope, the Webb is a joint project between NASA, the European Space Agency (ESA) and Canadian Space Agency (CSA).
The project has experienced numerous delays and cost overruns, ballooning from $500 million to almost $10 billion.
To fit inside the rocket, the telescope must be folded up, then unfolded in space in a series of manoeuvres in the first month after launch.
Webb features 18 hexagonal shaped mirrors arranged in a honeycomb shape 6.5 metres across, giving it a surface area 6.25 times larger than Hubble’s spherical 2.4m diameter primary mirror.
A Kapton foil sunshield the size of a tennis court blocks light from the sun, moon and Earth to keep the telescope extremely cool.
Webb will orbit the sun 1.5 million km from Earth at Lagrange point 2, where the gravitational pull from Earth and the sun balance out, allowing the observatory to remain stable.
While Hubble looks mostly in the visual and ultraviolet parts of the electromagnetic spectrum, Webb will look at longer wavelengths in the infrared, to see what the universe looked like around 100 to 250 million years after the Big Bang, when the first stars and galaxies were formed.
Webb will also look much closer to home, studying nearby exoplanets and objects within our solar system including Mars, the gas giants, and even some asteroids and comets.
- James Webb Space Telescope (NASA)
- The James Webb Space Telescope, NASA's next great observatory, passes final ground tests (Space.com)
- James Webb Space Telescope (ESA)
- The James Webb Space Telescope (New Scientsist)
- The Nail-Biting Journey of NASA’s James Webb Space Telescope Is About to Begin (Scientific American)