The AP is solely responsible for all content.Difference Between Hubble & James Webb Telescope: The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. NASA’s historian conducted an archival search of Webb this year and found no evidence warranting a name change, said Administrator Bill Nelson. But now some scientists and others want a new name, given Webb’s State Department and NASA leadership during the Truman administration, when government workers were fired for being gay. In 2002, a decade after Webb’s death, NASA chose his name for the new telescope. James Webb led NASA from 1961 to 1968, presiding over Projects Mercury and Gemini and the early phase of Apollo’s moon-landing program. Hubble and Webb namesakesĪstronomer Edwin Hubble confirmed a century ago that countless galaxies exist beyond our Milky Way and the universe is constantly expanding. The European Space Agency is picking up the launch costs, with a French-built Ariane rocket providing Webb’s lift from French Guiana. Webb’s price tag is an estimated $10 billion that includes the first five years of operation. ![]() ![]() That doesn’t include all the shuttle flights for launch and repairs. NASA’s tab for Hubble from its 1970s development until now: $16 billion, adjusted for inflation. Webb also is years late with huge cost overruns. Hubble was years late and millions over budget by the time it rocketed into orbit in 1990. Webb will constantly face the nightside of Earth as the spacecraft and planet swoop around the sun in unison. This is where the gravitational forces of the Earth and sun balance, requiring minimal fuel for a spacecraft to stay put. Webb is bound for a more distant spot - 1 million miles (1.6 million kilometers) away at what’s called the second Lagrange point. The altitude was dictated by the capabilities of NASA’s space shuttles, which delivered Hubble to orbit and then made five service calls. Hubble circles 330 miles (530 kilometers) overhead. Science & Medicine If NASA can overcome human error and other problems, its James Webb Space Telescope may finally launch in 2021 Each of the 18 hexagonal segments are the size of a coffee table and coated with ultra-thin gold, an ideal reflector of infrared light. It’s also segmented, allowing it to fold like a drop-leaf table for launch. That’s because Webb’s mirror is made of beryllium, a strong but lightweight metal. The mirror spans more than 21 feet (6.5 meters), yet is lighter than Hubble’s, which is 8 feet (2.4 meters) across. To discern the universe’s first, faint stars, Webb requires the largest mirror ever launched for astronomy. Multiple layers also better protect against micrometeorite hits. Between each of the sunshield’s five layers is a gap so heat can escape out the sides. To stay chilled, Webb carries a parasol the size of a tennis court. That’s why Webb’s detectors need to run at minus 400 degrees Fahrenheit (minus 240 degrees Celsius). The shorter visible and ultraviolet wavelengths emitted by the first stars and galaxies have been stretched as the universe expands, so Webb will see them in their elongated, heat-emitting infrared form. Webb has infrared vision, allowing it to pierce cosmic clouds of dust. Hubble sees what we see - visible light - with a little ultraviolet and infrared thrown in. “It’s like looking at the picture book of my kids and missing the first two years, right? Trying to figure out where they come from,” said NASA science chief Thomas Zurbuchen. Astronomers are eager to close the 300 million-year gap with Webb and draw ever closer in time to the Big Bang, the moment the universe formed 13.8 billion years ago. Hubble has stared as far back as 13.4 billion years, disclosing a clumpy runt of a galaxy that is currently the oldest and farthest object ever observed. This light will reveal how the original stars looked 13.7 billion years ago. Webb is expected to behold light from the universe’s first stars and galaxies, beyond Hubble’s range.
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