James Webb Space Telescope: The $10 Billion Christmas Present
The Hubble Space Telescope is one of the most important inventions of all time. The Hubble Space Telescope (HST) is one of the largest telescopes that we sent into low Earth orbit in 1990 and is one of NASA’s Great Observatories. To learn more about the other telescopes, click here. The HST uses an almost 8 ft mirror and other observation instruments to observe in ultraviolet, visible, and near-infrared. Because the HST is orbiting Earth, there is no atmospheric distortion, allowing it to capture amazing images of the universe. Because of the HST, we have made breakthroughs in astrophysics, discovered new planets and galaxies, proved older theories, and changed the way we explore space. However, the HST hasn’t been reliable, with 5 repair missions being sent to fix or repair certain systems. And with more recent problems, the desire to explore new frontiers, and the HST being over 30 years old, its replacement, the James Webb Space Telescope will launch today, December 25, 2021.
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| Render of JWST |
The James Webb Space Telescope (JWST) is a space telescope being jointly developed by NASA, the European Space Agency (ESA), and the Canadian Space Agency (CSA). Named after James Webb, NASA’s second administrator, the JWST will provide improved infrared resolution and sensitivity over the HST, allowing it to be utilized across the fields of astronomy and cosmology, including observing some of the most distant events and objects in the universe, such as the formation of the first galaxies, and detailed atmospheric characterization of potentially habitable exoplanets. To look for these planets, the JWST will look for cosmological redshift. I won’t go into too much detail right now and will write an article about it, but basically, the wavelength can be measured to determine where a planet is its size, and speed.
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| Mirror Segments Undergoing Cryogenic Testing |
Onboard the JWST, there are many scientific instruments. The NIRCam (Near InfraRed Camera is an infrared imager that will be able to sense the wavelength it is detecting. It was built by the University of Arizona. The NIRSpec (Near InfraRed Spectrograph) will perform spectroscopy on the same wavelength and was built by the ESA. The MIRI (Mid-InfraRed Instrument) will detect mid-to-long-infrared wavelength ranging from 5 to 27 micrometers and contains both a mid-infrared camera and an imaging spectrometer. Finally, there is the FGS/NIRISS (Fine Guidance Sensor and Near-Infrared Imager and Slitless Spectrograph) which will aid in the overall orientation and image stabilization of JWST. There is also the Spacecraft Bus, which hosts multiple computing, communication, power, propulsion, and structural parts, being the spacecraft part of JWST. JWST has 10 sets of thrusters, using hydrazine fuel and dinitrogen tetroxide as oxidizers.
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| JWST Spacecraft Bus |
The JWST first started development in the mid-1990s as NASA wanted to build a low-cost space telescope (we will talk about the $10 billion price tag soon). In 2003, NASA awarded an $824.8 million contract to TRW Inc. to develop JWST, with an initial launch date of 2010. However, due to multiple cost reevaluations and a 2005 re-plan, the JWST gained an additional $3.5 billion in its budget, as well as having contributions from the ESA and CSA. The Assembly of JWST started in 2007 and was completed in 2018. Since then multiple delays have been pushing the launch back.
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| Blueprint of JWST |
In recent months much later launch dates of 2018 or beyond have been rumored. But delays and cost overruns are nothing new for projects of unprecedented scale. Take the launch of the Hubble Space Telescope, which is a much smaller observatory than JWST, orbiting far closer to Earth, and whose deployment was a much simpler affair than the elaborate de-cocooning JWST will have to perform in deep space. Hubble was famously delayed by seven years, from a 1983 launch to a 1990 launch, and had just about tripled in cost by the time it reached orbit, according to a 1992 U.S. General Accounting Office (now the Government Accountability Office) report (pdf). Roughly $2 billion had already been sunk into the project by 1993, but its estimated cost had doubled from $5.3 billion to more than $11 billion. )
On 6 July 2011, the United States House of Representatives appropriations committee on Commerce, Justice, and Science moved to cancel the James Webb project by proposing an FY2012 budget that removed $1.9 billion from NASA's overall budget, of which roughly one quarter was for JWST.$3 billion had been spent and 75% of its hardware was in production. This budget proposal was approved by the subcommittee vote the following day. In response, the American Astronomical Society issued a statement in support of JWST, as did Maryland US Senator Barbara Mikulski. A number of editorials supporting JWST appeared in the international press during 2011 as well. In November 2011, Congress reversed plans to cancel JWST and instead capped additional funding to complete the project at $8 billion. Because the runaway budget diverted funding from other research, a 2010 Nature article described JWST as "the telescope that ate astronomy".
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| Full-Scale Model of JWST at NASA Goddard Flight Center |
The JWST has four main goals:
Search for light from the first stars and galaxies formed in the universe
Study the formation and evolution of galaxies
Understand the formation of stars and planetary systems
Study planetary systems and the origins of life
While the telescope’s nominal mission time is 5 years, the JWST will continue operation for much longer. To achieve its goals, the JWST will orbit near the second Lagrange point of the Earth-Sun system. This is around 930,000 miles from Earth, opposite of the Sun. JWST will circle around this L2 point in a halo orbit, taking half a year to complete a full orbit. 31 minutes after launch, the JWST will continue to expand for 13 days, deploying its solar array, antenna, sunshade, mirror, and arm, and will take nearly a month to reach its halo orbit.
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| JWST in Ariane 5 Rocket |
The JWST will launch on an Ariane 5 rocket on December 25 (hopefully it doesn’t get delayed, or I will have stayed up to watch the launch for nothing) from Guiana Space Centre in French Guiana. Unlike the HST, once launched, no fixes can be easily made on the JWST, so scientists and engineers are being extra cautious. The next launch opportunity will begin at 7:20 a.m. EST (1220 GMT), which the chance of being delayed due to weather, though that currently doesn’t seem like the case. You can watch the launch here.
The JWST is the next generation of space telescopes. In a couple of years, the JWST will be known by everyone like the Hubble Telescope is currently known. While the Hubble Space Telescope will be replaced, it won’t be obsolete. NASA will still use it to observe new and dying galaxies, but it won’t be the main priority anymore. With the JWST, we will be able to learn about the origins and first moments of the universe. Just think about it like the best Christmas present for us space enthusiasts and maniacs who want to know what is out there.
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| JWST Poster |
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