Northwestern Astronomer Part of Webb Telescope Team to Image Exoplanet | Chicago News


For the primary time, the James Webb Space Telescope has been used to straight picture an exoplanet — that’s a planet exterior of our photo voltaic system.

Although it’s not the primary time an exoplanet has been straight imaged, it’s the first time the Webb Telescope’s highly effective gaze has been turned to the duty.

And these, together with future observations might inform us extra about alien worlds past our photo voltaic system than ever earlier than — and simply perhaps, even detect life.

Jason Wang, assistant professor of physics and astronomy at Northwestern University’s Weinberg College of Arts and Sciences and a member of the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), spoke with WTTW News.

Wang was a part of the Webb staff that produced the exoplanet photos. (The interview has been edited for size and readability.)

WTTW News: This is the primary time the Webb Telescope has been used to straight picture a planet exterior our Solar System, nevertheless it’s not the primary time an exoplanet has been imaged, how does the Webb picture examine to earlier photos which were captured?

Wang: I believe the principle factor is it’s taken at completely different wavelengths. We’re a wavelength that we’ve by no means seen exoplanets earlier than straight. So that’s actually thrilling for us as a result of it permits us to see completely different elements of the planet’s ambiance. Look at completely different molecular absorption options … have a look at completely different molecular species within the ambiance to know composition. It additionally permits us to measure the whole power price range of the planet. So, with the ability to have a look at these different wavelengths which can be specifically inaccessible from ground-based telescopes is basically thrilling.            

Why was this specific planet chosen? We’re conscious of many exoplanets at this level. Why was this one chosen as a goal for Webb?               

That’s a terrific query. So it comes right down to sort of to 2 issues. One is we have now detected 1000’s of exoplanets, however solely a handful of them may be straight imaged as a result of we are able to solely see and take photos of the youngest exoplanets. So this planet is just a few million years previous, whereas the Earth is 4.5 billion years previous. So it’s a 1,000 instances youthful. It’s so younger that it shaped after the dinosaurs went extinct. And as a result of it’s so younger, it’s really glowing sizzling from its formation. It nonetheless retains that warmth. And due to that, it’s very shiny and that’s how we’re in a position to really take a picture of it.                

I had learn that the planet was a gasoline large many instances the scale of Jupiter and I assumed it was the scale that made it a very good goal.

You know, the scale additionally helps, however actually it’s the age that’s the key.

And so by way of the sunshine that you simply’re detecting, you’re not merely detecting the planet reflecting the sunshine from its solar, however you’re seeing the sunshine that’s mirrored by way of warmth from the creation of the planet.

Yeah, we’re seeing the thermal glow of the planet principally.

The Webb telescope has astronomers everywhere in the world excited. I might assume there have to be a really lengthy line of astronomers that desires to work on Webb.  How did you get to be one of many lucky ones?     

So this one, it finally ends up being a variety of us are the lucky ones. This specific goal and these specific photos that had been taken, that are among the many first photos taken with Webb, is a part of this program that NASA got here up with known as the early launch science program. Basically, the purpose is to make use of Webb to do a bunch of science (experiments) which can be designed to showcase the instrument’s efficiency for the scientific group. So principally your entire group of exoplanet imagers — these of us that wish to take photos of exoplanets — received collectively and principally submitted this program to principally take a look at out Webb.

In phrases of the challenges of imaging an exoplanet, I’m certain there have to be many, however what are among the chief challenges?  

To sort of offer you a way for the problem, it’s like making an attempt to see a firefly orbit a streetlight, however you’re standing a number of miles away. So it’s actually like for those who’re making an attempt to see this firefly from a number of miles away with some binoculars … you must take away all this glare, suppress the glare of the star to have the ability to see the planet that’s orbiting round it.    

So how is that achieved? Is it simply because Webb is so delicate and it’s capturing a lot mild that you are able to do this or do you must do a variety of picture processing? How does that work?    

So we do have to make use of slightly bit picture processing however we additionally benefit from the Webb. The optics of the Webb had been designed particularly to picture exoplanets. It has a sequence of optics inbuilt it known as coronagraphs. And these are designed to sort of block out the sunshine of the star as a lot as potential in order that we might see the faint mild of the planet. But often that’s not sufficient. What we have now to do is then additionally do picture processing after the very fact to discern these faint planets.

This image shows the exoplanet HIP 65426 b in different bands of infrared light, as seen from the James Webb Space Telescope. Purple shows the NIRCam instrument’s view at 3 micrometers, blue shows the NIRCam instrument’s view at 4.44 micrometers, yellow shows the MIRI instrument’s view at 11.4 micrometers and red shows the MIRI instrument’s view at 15.5 micrometers. (Credit: NASA/ESA/CSA, A Carter (UCSC), the ERS 1386 team and A. Pagan)This picture exhibits the exoplanet HIP 65426 b in numerous bands of infrared mild, as seen from the James Webb Space Telescope. Purple exhibits the NIRCam instrument’s view at 3 micrometers, blue exhibits the NIRCam instrument’s view at 4.44 micrometers, yellow exhibits the MIRI instrument’s view at 11.4 micrometers and crimson exhibits the MIRI instrument’s view at 15.5 micrometers. (Credit: NASA/ESA/CSA, A Carter (UCSC), the ERS 1386 staff and A. Pagan)

The photos I’m trying for the time being, I’m seeing 4 completely different photos in numerous colours. I do know from the caption that I’m seeing the planet in numerous bands of infrared mild, however clarify to me what astronomers can study from these photos?

What we are able to do is principally measure the brightness of the planet at completely different wavelengths and one of many issues you are able to do is add up the planet’s brightness in any respect the completely different wavelengths to sort of measure the whole power price range of the planet. Another factor we are able to do is search for wavelengths the place the planet is barely fainter than we count on in comparison with the opposite wavelengths. And if the planet is barely fainter at one wavelength that sort of tells us that there is perhaps some form of absorption characteristic that could possibly be resulting from molecular species within the atmospheric clouds within the ambiance. That sorts of tells us what this planet is made out of. So we are able to use these photos to know what this planet seems to be like and what it’s made out of.     

Given the ability of Webb, might it’s the instrument that really permits us to detect life past the Earth? Not essentially clever life however probably indicators of plants due to what we are able to inform about an exoplanet’s ambiance. Do you assume that Webb is an instrument that may enable us to try this?      

I believe it has a small likelihood. It’s not an enormous likelihood. I believe, , most of us aren’t holding our breath, however there are a number of specific methods, the spectrograph mode, that will have an opportunity of seeing one thing….  I believe that there’s just a few planets for which that could be potential. And clearly other people in our group are engaged on issues like that, however we’re not holding our breath ready for that proper now, simply because I believe the hopes are slim.

This is the primary exoplanet that Webb has imaged. Presumably it gained’t be the final. What can be among the future targets that you simply’re more likely to try to picture?           

I believe our group, not simply myself, however our group will most likely attempt to picture all the recognized recognized planets which were imaged earlier than. We’ll attempt to picture them utilizing Webb at these wavelengths that aren’t accessible from the bottom with the purpose of actually understanding what they’re made out of, how shiny they’re and perceive how the enormous planets types. So I believe planet formation and planet composition can be sort of key issues that we’ll be going after with Webb — at the very least from my pursuits.


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