Explainer: Comparing Two Space Telescopes
2022-01-03
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1On December 25, the new James Webb Space Telescope launched into space from South America on a European Ariane 5 rocket.
2"[countdown from 10 in French, continued in English] Lift off!
3From a tropical rainforest to the edge of time itself, James Webb begins a voyage back to the birth of the universe."
4NASA and the European Space Agency's Hubble telescope has been circling the Earth for nearly 32 years.
5Webb is widely seen as the next generation telescope.
6Experts recently spoke with The Associated Press about the differences between the two telescopes.
7But when talking with scientists of astronomy, do not ask them to pick a favorite.
8"Comparing Hubble and Webb is like asking if you love your second child as much as your first," said Susan Mullally.
9She is Webb's assistant project scientist at the Space Telescope Science Institute in Baltimore, Maryland in the United States.
10"Hubble will always be loved for its awe-inspiring images of our universe and will continue to collect important data for astronomers."
11But the Webb telescope, Mullally adds, will permit us to see places in the universe never before seen.
12The Webb telescope is bigger and 100 times more powerful than Hubble.
13In 1990, the Hubble caught a ride to its orbit inside NASA's space shuttle Discovery.
14For Webb, the NASA website explains that it was helpful for the launch to be near the equator because "...the spin of the Earth can help give an additional push."
15Hubble circles 530 kilometers overhead.
16That distance was determined by the abilities of NASA's space shuttles.
17When problems happened on Hubble, ground control specialists and astronauts were able to fix them.
18However, this will not be the case with Webb.
19Webb is heading to a much more distant spot -- 1.6 million kilometers away.
20If it runs into problems, it will be on its own.
21Webb is expected to record light from the universe's first stars and galaxies.
22This is beyond the abilities of Hubble.
23This light will show us how the original stars looked 13.7 billion years ago.
24Hubble has looked back as far as 13.4 billion years.
25Astronomers want to close that 300 million year hole with Webb.
26This will come ever closer in time to the Big Bang, the moment the universe formed 13.8 billion years ago.
27Hubble sees what we see - visible light.
28Webb has infrared vision, so it can see light that is invisible to the Hubble.
29It can see through clouds of space dust.
30The shorter visible and ultraviolet light given off by the first stars and galaxies have been stretched as the universe grows.
31So, Webb will see them in their infrared form, which is stretched out and giving off heat.
32Webb's detectors need to run at minus 240 degrees Celsius.
33To stay this cold, Webb carries an "umbrella" the size of a tennis court.
34Between each of the sunshield's five layers is a hole so heat can escape out the sides.
35To see the universe's first stars, Webb needs the largest mirror ever launched for astronomy.
36The Webb mirror is more than 6.5 meters.
37Hubble's is 2.4 meters across.
38However, Webb's mirror is lighter because it is made of beryllium, a strong but lightweight metal.
39The Hubble and Webb do have things in common: Production of both were years late and overbudget.
40NASA's cost for Hubble from its 1970s development until now is about $16 billion, adjusted for inflation.
41That does not include all the shuttle flights for launch and repairs.
42Webb's price tag is an estimated $10 billion.
43That includes the first five years of operation.
44The European Space Agency is paying for the launch costs.
45I'm Anna Matteo.
1On December 25, the new James Webb Space Telescope launched into space from South America on a European Ariane 5 rocket. 2"[countdown from 10 in French, continued in English] Lift off! From a tropical rainforest to the edge of time itself, James Webb begins a voyage back to the birth of the universe." 3NASA and the European Space Agency's Hubble telescope has been circling the Earth for nearly 32 years. Webb is widely seen as the next generation telescope. 4Experts recently spoke with The Associated Press about the differences between the two telescopes. But when talking with scientists of astronomy, do not ask them to pick a favorite. 5"Comparing Hubble and Webb is like asking if you love your second child as much as your first," said Susan Mullally. She is Webb's assistant project scientist at the Space Telescope Science Institute in Baltimore, Maryland in the United States. 6"Hubble will always be loved for its awe-inspiring images of our universe and will continue to collect important data for astronomers." But the Webb telescope, Mullally adds, will permit us to see places in the universe never before seen. The Webb telescope is bigger and 100 times more powerful than Hubble. 7In 1990, the Hubble caught a ride to its orbit inside NASA's space shuttle Discovery. For Webb, the NASA website explains that it was helpful for the launch to be near the equator because "...the spin of the Earth can help give an additional push." 8Location and problems in space 9Hubble circles 530 kilometers overhead. That distance was determined by the abilities of NASA's space shuttles. When problems happened on Hubble, ground control specialists and astronauts were able to fix them. 10However, this will not be the case with Webb. Webb is heading to a much more distant spot -- 1.6 million kilometers away. If it runs into problems, it will be on its own. 11All the light we see 12Webb is expected to record light from the universe's first stars and galaxies. This is beyond the abilities of Hubble. This light will show us how the original stars looked 13.7 billion years ago. 13Hubble has looked back as far as 13.4 billion years. Astronomers want to close that 300 million year hole with Webb. This will come ever closer in time to the Big Bang, the moment the universe formed 13.8 billion years ago. 14Infrared vision 15Hubble sees what we see - visible light. 16Webb has infrared vision, so it can see light that is invisible to the Hubble. It can see through clouds of space dust. The shorter visible and ultraviolet light given off by the first stars and galaxies have been stretched as the universe grows. So, Webb will see them in their infrared form, which is stretched out and giving off heat. 17Webb's detectors need to run at minus 240 degrees Celsius. To stay this cold, Webb carries an "umbrella" the size of a tennis court. Between each of the sunshield's five layers is a hole so heat can escape out the sides. 18Larger mirror 19To see the universe's first stars, Webb needs the largest mirror ever launched for astronomy. 20The Webb mirror is more than 6.5 meters. Hubble's is 2.4 meters across. However, Webb's mirror is lighter because it is made of beryllium, a strong but lightweight metal. 21Production and costs 22The Hubble and Webb do have things in common: Production of both were years late and overbudget. 23NASA's cost for Hubble from its 1970s development until now is about $16 billion, adjusted for inflation. That does not include all the shuttle flights for launch and repairs. 24Webb's price tag is an estimated $10 billion. That includes the first five years of operation. The European Space Agency is paying for the launch costs. 25I'm Anna Matteo. 26The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute's Department of Science Education. The AP is solely responsible for all content. 27__________________________________________________ 28Words in This Story 29tropical - adj. of or occurring in the tropics 30astronomy - n. the scientific study of stars, planets, and other objects in outer space : astronomer - n. a person who is a specialist in astronomy 31awe-inspiring - adj. that arouses awe or wonder 32spin - v. to turn or cause someone or something to turn around repeatedly 33galaxy - n. any of the very large groups of stars and associated matter that are found throughout the universe 34infrared - adj. producing or using rays of light that cannot be seen and that are longer than rays that produce red light 35vision - n. the act or power of seeing 36ultraviolet - adj. used to describe rays of light that cannot be seen and that are slightly shorter than the rays of violet light 37detector - n. a device that can tell if a substance or object is present 38mirror - n. a piece of glass that reflects images