About The Webb
The James Webb Space Telescope (sometimes called JWST or Webb) will be a large infrared telescope with a 6.5-meter primary mirror. The telescope will be launched on an Ariane 5 rocket from French Guiana in October of 2018.
JWST will be the premier observatory of the next decade, serving thousands of astronomers worldwide. It will study every phase in the history of our Universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets like Earth, to the evolution of our own Solar System.
JWST was formerly known as the “Next Generation Space Telescope” (NGST); it was renamed in Sept. 2002 after a former NASA administrator, James Webb.
JWST is an international collaboration between NASA, the European Space Agency (ESA), and the Canadian Space Agency (CSA). The NASA Goddard Space Flight Center is managing the development effort. The main industrial partner is Northrop Grumman; the Space Telescope Science Institute will operate JWST after launch.
Several innovative technologies have been developed for JWST. These include a primary mirror made of 18 separate segments that unfold and adjust to shape after launch. The mirrors are made of ultra-lightweight beryllium. JWST’s biggest feature is a tennis court sized five-layer sunshield that attenuates heat from the Sun more than a million times. The telescope’s four instruments – cameras and spectrometers – have detectors that are able to record extremely faint signals. One instrument (NIRSpec) has programmable microshutters, which enable observation up to 100 objects simultaneously. JWST also has a cryocooler for cooling the mid-infrared detectors of another instrument (MIRI) to a very cold 7 K so they can work (Jwst.Nasa.gov, 2016).
Who Is James Webb
The man whose name NASA has chosen to bestow upon the successor to the Hubble Space Telescope is most commonly linked to the Apollo moon program, not to science.
Yet, many believe that James E. Webb, who ran the fledgling space agency from February 1961 to October 1968, did more for science than perhaps any other government official and that it is only fitting that the Next Generation Space Telescope would be named after him.
A Balanced Program
Webb’s record of support for space science would support those views. Although President John Kennedy had committed the nation to landing a man on the moon before the end of the decade, Webb believed that the space program was more than a political race. He believed that NASA had to strike a balance between human space flight and science because such a combination would serve as a catalyst for strengthening the nation’s universities and aerospace industry (Jwst.Nasa.gov, 2016).
How does the Webb Contrast with Hubble?
Webb often gets called the replacement for Hubble, but we prefer to call it a successor. After all, Webb is the scientific successor to Hubble; its science goals were motivated by results from Hubble. Hubble’s science pushed us to look to longer wavelengths to “go beyond” what Hubble has already done. In particular, more distant objects are more highly redshifted, and their light is pushed from the UV and optical into the near-infrared. Thus observations of these distant objects (like the first galaxies formed in the Universe, for example) requires an infrared telescope.
This is the other reason that Webb is not a replacement for Hubble is that its capabilities are not identical. Webb will primarily look at the Universe in the infrared, while Hubble studies it primarily at optical and ultraviolet wavelengths (though it has some infrared capability). Webb also has a much bigger mirror than Hubble. This larger light collecting area means that Webb can peer farther back into time than Hubble is capable of doing. Hubble is in a very close orbit around the earth, while Webb will be 1.5 million kilometers (km) away at the second Lagrange (L2) point (Jwst.Nasa.gov, 2016).
The James Webb Space Telescope will be launched on an Ariane 5 rocket. The launch vehicle is part of the European contribution to the mission. The Ariane 5 is the world’s most reliable launch vehicle capable of delivering Webb to its destination in space. The European Space Agency (ESA) has agreed to provide an Ariane 5 launcher and associated launch services to NASA for Webb. The Ariane 5’s record for successful launches extends over 11 years and some 57 consecutive launches (as of February 2014).
Credit: Arianespace – ESA – NASA
JWST will be launched from Arianespace’s ELA-3 launch complex at European Spaceport located near Kourou, French Guiana. It is beneficial for launch sites to be located near the equator – the spin of the Earth can help give an additional push. The surface of the Earth at the equator is moving at 1670 km/hr (Jwst.Nasa.gov, 2016).
The Launch Segment has 3 primary components:
- Launch Vehicle: an Ariane 5 with the cryogenic upper stage. It will be provided in the single launch configuration, with a long payload fairing providing a maximum 4.57 meter static diameter and useable length of 16.19 meters.
- Payload Adapter, comprising the Cone 3936 plus ACU 2624 lower cylinder and clamp-band, which provides the separating mechanical and electrical interface between the Webb Observatory and the Launch Vehicle.
- Launch campaign preparation and launch campaign.
The launch campaign preparation and launch campaign is the mutual responsibility of NASA, ESA, NGAS, and Arianespace (Jwst.Nasa.gov, 2016).
For near daily updates of images, videos, news, events, as well as interesting JWST related facts and information go to http://jwst.nasa.gov/news_archive.html
JWST.NASA.gov (2016). Explore James Webb Space Telescope. Retrieved from: http://jwst.nasa.gov/
NASA.gov (2013). James Webb Space Telescope Backplane Arrives at Marshall for Testing. Retrieved: http://www.nasa.gov/centers/marshall/news/news/releases/2013/13-099a.html