After years of budget overruns, testing problems and political difficulties, NASA’s next great telescope has been delayed again, the space agency announced Thursday. The James Webb Space Telescope, which was proceeding toward a launch date of March 2021, will now be launched no sooner than Oct. 31, 2021.
In a news conference Thursday, NASA officials blamed the delay on disruptions caused by the coronavirus pandemic and on schedule reviews that started last winter. “Mission success is critical, but team safety is our highest priority,” said Stephen Jurczyk, NASA’s associate administrator.
NASA said the delay would not add to the project’s overall cost, which was capped at $8.8 billion by Congress a few years ago, because the program had reserves in its budget. “Based on current projections, the program expects to complete the remaining work within the new schedule without requiring additional funds,” said Gregory Robinson, the program director for Webb at NASA.
Nor would it impact the ability of the Webb telescope to work with the Hubble Space Telescope, which the agency says will now last into the 2030s.
The telescope, named after James Webb, who led the space agency in the 1960s, is the long-awaited successor to Hubble. “Webb is designed to build upon the incredible legacies of the Hubble and Spitzer space telescopes by observing the infrared universe and exploring every phase of cosmic history,” said Eric Smith, Webb’s program scientist.
Seven times larger than the Hubble in light-gathering ability, the Webb was designed to see farther out in space and deeper into the past of the universe. It may solve mysteries about how and when the first stars and galaxies emerged some 13 billion years ago in the smoky aftermath of the Big Bang.
The telescope’s main mirror is 6.5 meters in diameter, or just over 21 feet, compared with 2.4 meters for the Hubble. Its mission is to explore a realm of cosmic history stretching from about 150 million to one billion years after time began — known as the reionization epoch, when bright and violent new stars and the searing radiation from quasars were burning away a gloomy fog of hydrogen gas that prevailed at the end of the Big Bang.
Astronomers theorize that during that epoch, an initial generation of stars made purely of hydrogen and helium — the elements created during the Big Bang — burned ferociously and exploded apocalyptically, jump-starting the seeding of the cosmos with progressively more diverse materials. But nobody has ever seen any so-called Population 3 stars, as those first stars are known. They don’t exist in the modern universe. Astronomers have to hunt them in the dim past.
That ambition requires the Webb to be tuned to a different kind of light than our eyes or the Hubble can see. Because the expansion of the cosmos is rushing those earliest stars and galaxies away from us so fast, their light is “red-shifted” to longer wavelengths, the way the siren from an ambulance shifts to a lower register as it passes by.
So blue light from an infant galaxy bursting with bright spanking new stars way back then has been stretched, by the time it reaches us 13 billion years later, to invisible infrared wavelengths, or heat radiation which Webb is equipped to detect.
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Frequently Asked Questions
Updated July 16, 2020
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Is the coronavirus airborne?
- The coronavirus can stay aloft for hours in tiny droplets in stagnant air, infecting people as they inhale, mounting scientific evidence suggests. This risk is highest in crowded indoor spaces with poor ventilation, and may help explain super-spreading events reported in meatpacking plants, churches and restaurants. It’s unclear how often the virus is spread via these tiny droplets, or aerosols, compared with larger droplets that are expelled when a sick person coughs or sneezes, or transmitted through contact with contaminated surfaces, said Linsey Marr, an aerosol expert at Virginia Tech. Aerosols are released even when a person without symptoms exhales, talks or sings, according to Dr. Marr and more than 200 other experts, who have outlined the evidence in an open letter to the World Health Organization.
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What are the symptoms of coronavirus?
- Common symptoms include fever, a dry cough, fatigue and difficulty breathing or shortness of breath. Some of these symptoms overlap with those of the flu, making detection difficult, but runny noses and stuffy sinuses are less common. The C.D.C. has also added chills, muscle pain, sore throat, headache and a new loss of the sense of taste or smell as symptoms to look out for. Most people fall ill five to seven days after exposure, but symptoms may appear in as few as two days or as many as 14 days.
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What’s the best material for a mask?
- Scientists around the country have tried to identify everyday materials that do a good job of filtering microscopic particles. In recent tests, HEPA furnace filters scored high, as did vacuum cleaner bags, fabric similar to flannel pajamas and those of 600-count pillowcases. Other materials tested included layered coffee filters and scarves and bandannas. These scored lower, but still captured a small percentage of particles.
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Is it harder to exercise while wearing a mask?
- A commentary published this month on the website of the British Journal of Sports Medicine points out that covering your face during exercise “comes with issues of potential breathing restriction and discomfort” and requires “balancing benefits versus possible adverse events.” Masks do alter exercise, says Cedric X. Bryant, the president and chief science officer of the American Council on Exercise, a nonprofit organization that funds exercise research and certifies fitness professionals. “In my personal experience,” he says, “heart rates are higher at the same relative intensity when you wear a mask.” Some people also could experience lightheadedness during familiar workouts while masked, says Len Kravitz, a professor of exercise science at the University of New Mexico.
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What is pandemic paid leave?
- The coronavirus emergency relief package gives many American workers paid leave if they need to take time off because of the virus. It gives qualified workers two weeks of paid sick leave if they are ill, quarantined or seeking diagnosis or preventive care for coronavirus, or if they are caring for sick family members. It gives 12 weeks of paid leave to people caring for children whose schools are closed or whose child care provider is unavailable because of the coronavirus. It is the first time the United States has had widespread federally mandated paid leave, and includes people who don’t typically get such benefits, like part-time and gig economy workers. But the measure excludes at least half of private-sector workers, including those at the country’s largest employers, and gives small employers significant leeway to deny leave.
It also turns out that infrared emanations are the best way to study exoplanets, the worlds beyond our own solar system that have been discovered in the thousands by observatories in space and on the ground since the Webb telescope was conceived.
In order to see those infrared colors, however, the telescope has to be very cold — less than 45 degrees Fahrenheit above absolute zero — so that its own heat does not swamp the heat from outer space. Once in space, the telescope will unfold an umbrella the size of a tennis court to keep the sun off it. The telescope, marooned in permanent shade a million miles beyond the moon, will experience an infinite cold soak.
The sun shield consists of five thin, kite-shaped layers of a material called Kapton. Much too big to fit into a rocket, the shield, as well as the telescope mirror, will have be launched folded up, and testing the shield on Earth has proved devilishly difficult. It will then be unfolded in space over six months in a series of 180 maneuvers that look in computer animations like a cross between a parachute opening and a swimming pool cover going into place.
Or at least that is the plan. That whole process will amount to what the engineers call “six months of high anxiety.” In space, nobody will be there with a wrench to help. Which means it will be a long nervous wait for the next set of cosmic baby pictures.
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