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What kind of light will Webb see?


Uploaded on January 7, 2022


What kind of light will Webb see?

2022-01-07 – There are many kinds of light all around us: the rainbow of light we can see, and several other types – like X-rays, infrared, microwaves, radio waves – that are not visible to the human eye.

The James Webb Space Telescope will use infrared light to study every phase in cosmic history.

The telescope's four scientific instruments are specifically designed to capture infrared light, and will be able to peer through cosmic dust to study colder or very distant objects. Certain types of objects, such as planets and very distant galaxies, shine most brightly in infrared light. (Credits: Canadian Space Agency, NASA, ESA and the Hubble Heritage Team (STScI/AURA), J. Lee and the PHANGS-HST Team)


Sarah Gallagher: We asked you what you wanted to know about the science of Webb.

David Saint-Jacques: And we’re here to answer your questions.

David Saint-Jacques: Hi, I’m David Saint-Jacques.

Sarah Gallagher: And I’m Sarah Gallagher.

David Saint-Jacques and Sarah Gallagher: And you are an astrophysicist!

Sarah Gallagher: What wavelengths of light does the Webb Telescope use? Does it specialize in one or multiple wavelengths of light?

David Saint-Jacques: Webb will observe in the infrared spectrum, essentially looking at heat sources.

But why are infrared observations important to astronomy?

Stars and planets that are just forming lie hidden behind dust clouds that absorb visible light. Infrared light can pass through this dust to reveal what is inside.

This allows Webb to look much closer to the beginning of the universe and hunt for the unobserved formation of the first galaxies, but also look at stars and planets that are forming today.

David Saint-Jacques : More questions will arise as Webb opens a new chapter in our understanding of the universe.

Sarah Gallagher: Join astronomers from across Canada and around the world on a thrilling journey of discovery.


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