The relief was as deep as the stakes were high. The rocket carrying the largest, most ambitious space telescope in history cleared the launchpad in French Guiana at 7:21 A.M., and the members of mission control at the Space Telescope Science Institute in Baltimore roared their joy.
The suspense was not over. The telescope needed to decouple from its host rocket after it had to deploy solar panels. The first deployment proved to be a success, and NASA would know they had a mission after that, according to a NASA spokesman. The announcement of a successful rocket separation and solar-array deployment was almost drowned out by cheers.
Astronomers are more likely to ride the rocket than theJWST. The viability of NASA's space-science portfolio is at risk if not the future of astronomy itself. The successor to the Hubble Space Telescope is one of those once-in-a-generation scientific projects that can strain the patience of government benefactors as well as the responsible agency's credibility but also define a field for decades to come.
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Bill Nelson, administrator of NASA, said that this is a great day for America and the European and Canadian partners. There is great risk in reward. That is what this business is all about, and that is why we dare to explore. The exploration is a part of the James Webb Space Telescope.
Back to the beginning.
The telescope that would become JWST was already under discussion. The line of sight would be free of the optical distortions endemic to our planet's atmosphere. It would be able to see farther across the universe because of the finite speed of light.
The human eye can detect the small portion of the spectrum that is visible in optical wavelength. The Next Generation Space Telescope would be looking at the universe in a different way than the current one, which looks at the universe in visible light.
Much of the attention leading up to today's launch has focused on the ability of JWST to peer farther into the past than the HST, which has observed infant galaxies as far back as 400 million years after the big bang. The universe had already undergone several generations of evolution, including the merging and shredding ofgalaxies, the creation of space with additions to the periodic table of the elements, and the birth of sentient beings on Earth.
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After the big bang, most of the matter consisted of the primordial elements and was just beginning to coalesce into stars and galaxies. The primary goal has been to see the first objects in the universe.
A new search for life.
One of the major scientific frontiers that will be probed by the JWST is one that has received less attention but could prove to be just as important in our understanding of the universe. The subject of study those 1980s-era visionaries could not have foreseen is exoplanets.
Some of the discoverers of this year's Nobel Prize in physics earned a share of the prize because of the evidence for planets outside the sun. Astronomers have found thousands of exoplanets since then, with tens of thousands more to come in coming years. Most of the discoveries rely on indirect evidence, such as the periodic dimming of a star as a planet transits across its face or the wobble in a star's axis caused by the pull of a nearby world.
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Only a few other facilities can offer more direct evidence, and none with the promised clarity of this new space telescope. In visible light, a star's brightness overwhelms any nearby objects, but by observing in the IR, the contrast will be reduced so that the planets can pop out from the background stellar glare as tiny blips of light. Observers will be able to probe the atmospheres of a few worlds for biosignatures such as oxygen and water, as well as trace elements of habitability such as carbon dioxide.
It's slim to answer an eternal question: Are we alone?
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Nicholas Suntzeff is an astronomer at Texas A&M and former vice president of the American Astronomical Society. Is there life in the universe? It would have to be the biggest discovery in science ever.
Near-Death Experiences.
But first, you know, work.
Many of the members of the project were not yet born when the project was launched. Just as NASA is haunted by what happened next, they are shadows by what happened next. The Space Telescope Science Institute is the operations headquarters for the observatory and now mission control. After initial observations were out of focus, engineers realized that the mirror had been polished wrong, leading to a ruinous case of public ridicule. The fiasco was a classic example of the saying, "You had only one job, and it was to fix the mirror."
Significant setbacks have preceded the launch of the JWST. The original budget estimate was a bit hazy, and the launch date was not clear. By that time, the costs had risen to $5 billion and the development of the telescope was proving more difficult than planners had thought. The budget ballooned by 60 percent to $8 billion in a single year, which prompted Congress to establish a cost cap.
Would Congress be able to cancel a scientific mission? Yes, and once did. The world's most powerful particle collider was killed in 1993 by a bill signed by President Bill Clinton. The project cost $2 billion and will cost $3 billion in 2021. The boring had already cleared 19 of the projected 51 miles of tunnel. The particle accelerator promised scientific breakthrough. The project's budget was out of control. The cancellation blew a hole in the heart of the U.S. particle physics community, which has yet to fully recover.
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The launch date was pushed farther and farther into the future by the JWST project. An investigation by the Government Accountability Office revealed that the observatory's propulsion valves were damaged when an inappropriate solvent was applied. The pressure transducers were destroyed by a wiring error. Dozens of bolts flew off the spacecraft during testing.
The budget grew by another $800 million. The launch date was moved to 2021.
The name of the telescope has caused controversy. Sean O'Keefe, NASA's administrator at the time, announced in 2002 that the Next Generation Space Telescope would be called the James Webb Space Telescope. Replacing generic names for telescopes and observatories with the names of prominent scientists is a routine practice. One of O'Keefe's predecessors was the one who was honored, but the choice of the honoree was essentially a solo decision. NASA had a chief named James E. Webb from 1961 to 1968.
The name of the mission has become a topic of controversy in recent years. The lavender scare, a search for and purge of LGBTQ employees at these and other federal institutions, occurred during the tenure of the second in command at the Department of State and then as the head of NASA. The association between bigotry and the project is close enough that some people insist on referring to the project only as "JWST" and never as "Webb."
Will it work?
There have been delays on the way to the launchpad. The launch date has been changed several times in recent weeks due to a flaw in the communication cable connecting the telescope to the ground systems and an accidental jostling of the telescope. A forecast of high winds for the launch site in French Guiana pushed the liftoff from Christmas Eve to Christmas Day.
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Over the next month, the JWST will have to execute nearly 350 potentially fatal maneuvers while preparing for scientific observations. The deployment of the mirror will be the most difficult of all. The telescope would not be too heavy to launch, so engineers chose to make the mirrors out of a lighter element. The weight of the mirrors was not the most difficult design challenge. It was their size.
The mirrors will span more than 21 feet, far too wide for a rocket's payload fairing, when they assume their configuration. Engineers came up with an ingenious solution: divide the honeycomb into segments that fold up so that they fit inside the rocket on Earth, then unfold in space.
The second Lagrange point, or L2, is one of five sites in the solar system that the 19th-century Italian-French mathematician Joseph- was named after. The Earth and sun's balance between them acts as a stabilizing influence, allowing for spacecraft to conserve fuel. Other astronomy projects that have occupied L2 include the Herschel and Planck space observatories.
L2 is on the side of Earth opposite the sun, which reduces exposure to light and also to heat, an essential concern in an instrument sensitive to IR. Even so, the thermal protection will still be needed so that the temperature can be only a few degrees above absolute zero. The telescope will have a five-layer sun shield to protect it from heat pollutants during the first week of its voyage. On the telescope side of the shield, the temperature can reach 400 degrees F.
L2 is far from Earth, or four times the distance of the moon, and it has all the advantages. The benefit of human servicing missions was that they were able to fix the flaw in its mirror. The option will not be available for the event. It will stay broken if something breaks.
The European Space Agency and the Canadian Space Agency will receive 15 percent and 5 perfect of observation time, respectively, if nothing breaks this summer. The telescopic treasures will contain new insights into the origins of the universe and the atmospheres of exoplanets, as well as the secrets of star formation and the geology of the outer planets in our solar system.
Only then will members of the worldwide JWST community be able to relax and celebrate Christmas in July.
