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Speaker 0 00:00:00 All systems are go we're inside a minute. Now, T minus 50 seconds in counting
Speaker 1 00:00:04 On December 25th, 2021, a rocket, roughly the size of the statue of Liberty lifted off in French Guyana packed on board. The most advanced infrared telescope in the history of mankind, the rocket escaped Earth's orbit. And weeks later, the James space telescope reached its destination LaGrange 0.2, a stationary point, a million miles away from earth, perfectly balanced between the sun and the Earth's orbits free from interference.
Speaker 0 00:00:38 And we have star De lift off from a tropical rainforest to the edge of time itself. James Webb begins a voyage back to the birth of the universe.
Speaker 1 00:00:53 The field of astronomy stands on the precipice of scientific discovery. Webb has fully deployed culminating two and a half decades of planning and resulting in a device a hundred times more powerful than the aging Hubble telescope people are understandably excited, probably none more so than those involved on the scientific side of web. The astronomers with projects approved for web's initial round of research, the scientists at NASA who put this research into action, and the individuals organized this entire process from the very start, just like launching a satellite into space, discovering the secrets of the universe with web telescope is a multi-stage process
Speaker 3 00:01:32 So far so good, but there are a lot more steps, uh, ahead of us. Uh, but man, if it all comes together, the way it's supposed to, it is going to knock our socks off.
Speaker 4 00:01:44 I'm rather hoping there's a discovery that says, gosh, we didn't know that was there, but we have to go look at that more.
Speaker 1 00:01:49 That's Dr. John Mather,
Speaker 4 00:01:50 Um, senior project scientist for the James web space telescope. And I work at NASA Godard space flight center, which is just outside Washington, DC
Speaker 1 00:01:58 In 2006, Dr. Mather received a Nobel prize in physics for his war on cosmic microwave, background radiation, those discoveries help cement the big bang model as the leading theory behind the origin of the universe. He's a big deal in the world of astrophysics.
Speaker 4 00:02:13 Well as senior project scientist, I'm responsible for deciding what we ought to do, uh, collectively with all the scientists that we work with and, uh, making sure that our engineering team can, that it's pretty challenging.
Speaker 1 00:02:25 Mather is the last original JWST team member still at NASA. Having been the head scientist on web since 1995, when the project began, he helped decide the scientific instruments. That would be a board web.
Speaker 4 00:02:39 We had committees and committees and committees, and we argued and argued in the initial sketch. This is what astronomers really want. And let's see if we can find a way to make it happen.
Speaker 1 00:02:49 The engineering to get web into L two orbit is complicated enough, but settling on the best tools to pack is a beast unto itself. Sure. There have been infrared space telescopes before, but never one in an orbit so far away as web mess up and you'll realize the screw you're trying to loosen doesn't fit the Phillips head screwdriver in your pocket. And the tool cabinet is a million miles away. NASA needed to make sure the tools aboard web were the right ones for the present moment and the future.
Speaker 4 00:03:19 Basically, we said, well, we've got these wonderful scientific challenges and how could you possibly observe something that would tell you to answer? It's a little too hard to anticipate what scientists went to do 10, 20, 30 years in the future. We'd better have a general purpose set of tools.
Speaker 1 00:03:35 NASA settled on four scientific instruments, a near infrared spectrograph and camera called nurse spec. Inam a mid-infrared instrument called mirror and a combination fine guidance sensor and near infrared imaging tool. Each of these instruments include components commonly found in research telescopes, including the spectometer.
Speaker 4 00:03:56 We hear that a picture is worth a thousand words. Well, for an astronom, a spectrum is worth a thousand pictures. The spectrometer allows you chemical composition of that object, how hot it is, how it's moving. And, um, sometimes even more like what's the pressure we spend a lot of time and effort to get a spectrum of an object.
Speaker 1 00:04:15 Web also has its own set of specialized components to address its unique situ it's the only space telescope equipped with a micro shutter array, a grid of a quarter million tiny shutters that can be open and closed individually. This allows web to capture spectrometry data for a hundred individual objects, all in a single light exposure.
Speaker 4 00:04:36 The way we from our project side did it was we're gonna build a tool and then we're gonna ask the, the astronomy world. Okay, what do you wanna work on today? So we asked him all to send it in proposals,
Speaker 5 00:04:47 All these elements that we sort of take for granted and are just here on the earth. Gold silver they're in platinum. Yeah. We still are trying to track down where they come from in the universe.
Speaker 1 00:04:57 That's Dr. Charlie Gilpatrick. He works as a post doc fellow at, at Northwestern university, specifically in the center for interdisciplinary exploration and research in astrophysics.
Speaker 5 00:05:08 I mostly study things that, that change on the sky on day to week, time scales.
Speaker 1 00:05:14 In other words, KPA spends time looking at super Nova fast radio bursts and other explosions that it happened in space.
Speaker 5 00:05:23 I've used telescopes in Hawaii, like ke and pan stars, uh, telescopes in Chile, like the SW telescope, and then of course, space based telescopes. So primarily Hubble in the past. And, and yeah, now I have the James webspace telescope program
Speaker 1 00:05:40 Two and a half years ago, Dr. Was studying super Nova and how they produce elements like oxygen and Silicon.
Speaker 5 00:05:47 We can actually see all of the elements that a supernova produces and sort of add them up and infer how much ejecta it produced in the first place.
Speaker 1 00:05:57 Ke Patrick thought this methodology could potentially be used to study another phenomenon called a Killan Nova, whereas a supernova forms after a single star collapses in on itself, a Killan Nova is when a neutron star Karine into another neutron star and tears, a smaller one apart
Speaker 5 00:06:14 Nebular supernova. So super Nove go through the exact same nebular phase as ANOVA is expected to go through.
Speaker 1 00:06:22 He hypothesized that ki Nova could be the source behind the universe's heavier elements with that KPA filled out a project proposal with himself as the principal investigator.
Speaker 5 00:06:33 For the very first time, we, we would be able to say exact where elements like neodymium heavy elements that are sort of around that, that one on the periodic table are formed. You know, that's a huge draw in terms of, you know, how James WEG would be able to sort of take a, like a qualitative step forward into the next generation of nuclear astrophysics.
Speaker 1 00:06:57 At this point, Kerick had the scientific justification for the project, the method, the goal, and the belief that this could lead to a huge discovery,
Speaker 5 00:07:06 You know, after that was really the hard work of like proving that it, it would be actually practical to do,
Speaker 1 00:07:12 To write up the actual project proposal Kerick and his team used especially made computer program called the astronomers proposal tool. They specified what observations they wanted web to do. That means marking down the instruments web should use the exact target in space where web should look and how many hours to spend looking, stuff like that.
Speaker 5 00:07:31 We had sort of this huge effort of the course of like three or four weeks where we were collaborating on this proposal, but also some other ones that are also related to ki OB to try to figure out whether this would work and then write everything together.
Speaker 6 00:07:45 So I actually have two programs that have been approved. One is as a guaranteed time observer,
Speaker 1 00:07:50 That's Dr. Christine Chen, she's a research scientist at the physics and astronomy department at John's Hopkins university. She studies how Terry systems form and evolve.
Speaker 6 00:08:01 And then the second there's a, also a general observer program. And this is the typical mode through which people get observatory time, where they, um, apply to the observatory.
Speaker 1 00:08:10 Dr. Chen is also an astronomer at the space telescope science Institute, STS C as it's stone for short is the organization that manages scientific operations for both Hubble. And JWST amongst your chief responsibilities running the telescope allocation process.
Speaker 6 00:08:28 I've worked on, uh, JW T for many years. And my current role is in, um, science policies. So I am the lead for the James web space, teleco science policies group.
Speaker 1 00:08:40 I like most things. Web has a limited lifespan. NASA expects that to be anywhere from five to 10 plus years. So it's imperative that we make the most of the time we have with it. S T S E I gathers the project proposals and ensures that there's always something Webb can be doing.
Speaker 6 00:08:55 One of the great things about JW S T is it's an open skies observatory, which means that anyone from all over the world is welcome to apply
Speaker 1 00:09:03 Astronomers like Dr. KPA, who are looking to get observation time submit project proposals through the JWST general observer program. This
Speaker 6 00:09:12 Is the typical mode through which people get observatory a time where they, um, apply to the observatory
Speaker 1 00:09:18 Research aboard web is organized into yearly cycles for reference Hubble completed cycle 29 in its 29th year of operation. In January of 20 20 10, enter team announced the call for proposals for JWST cycle one.
Speaker 6 00:09:34 You can imagine there's so much interest that we get a lot of proposals. So I forget the exact number for cycle one, but it's on the order of 1,200 proposals came in.
Speaker 1 00:09:43 The proposals addressed all areas of astrophysics accommodating. All of them would've required 24 and a half thousand hours of prime observing time web only had 6,000 hours available. They needed to make some cuts. T S C. I created a committee of scientists, each experts in their own subdiscipline to sift through these proposals for this process, they use a combination of a triage system and paneled discussions. Each proposal gets read by six different committee members who then score the proposal according to how well it meets three set of criteria. First, the scientific merit of the project,
Speaker 6 00:10:19 The contribution to the advancement of knowledge. How does it impact our knowledge within a specific subfield
Speaker 1 00:10:26 Second, the project's possible impact on astronomy as a whole,
Speaker 6 00:10:30 In this particular case. What we're looking for is not just relevance to the particular topical panel proposal goes to, but other topical panels as well. So like, for example, if you are in exoplanets, uh, proposal, you know, is there an implication for like solar system work, right? That that's a kind of cross panel thing.
Speaker 1 00:10:51 Then finally the projects need for JWST to accomplish its scientific goals.
Speaker 6 00:10:56 Of course, top time on JST is extremely precious. And so if you can do that science with another facility, you know, it's, it's better to, to do that, to use that instead. And, and those are the same selection criteria actually that are used for hub space telescope as James webspace, telescope
Speaker 1 00:11:13 Discussions, then take place over a three week process organized by Chen's team, a process so complex, it rivals the moon landing in logistics. They're
Speaker 6 00:11:22 Highly organized, and you can imagine it, they have to be because we have people from all over the world participating and particularly through the pandemic, you know, we're, we do this all like on zoom essentially. You know, that means that these panels, people are awake both in Hawaii and in Europe at this same time,
Speaker 1 00:11:38 The panels spend three weeks discussing each day, the panel spends six hours vetting in selecting the proposals. Again, that's six hours every day.
Speaker 6 00:11:47 It's grueling because, you know, there are very detailed conversations where people really try to probe into like, you know, like how impactful is this science like, you know, is it, you know, something that's going to change our understanding of astronomy or not. And then, you know, on the technical side, like, does this make sense? Will it work? So they have to have these really detailed probing discussions.
Speaker 1 00:12:10 These zoom calls that are held across scores of time zones and consonants will directly lead to some of JWS T's most impactful discoveries. Every proposal has a possibility of forever changing how we see the universe itself, facilitating those discoveries. That's a big responsibility. And though 10 herself doesn't directly select projects. Her team works for remove any bias from that selection process. That's been a big issue in the past for NASA and the Hubble space telescope. The time allocation committee for Hubble had a long history of rejecting a disproportionate amount of proposals with women as their principal investigators, there would routinely be a 5% difference between the, a proposal acceptance rates for men and women.
Speaker 6 00:12:56 It was an important thing to address essentially that there is bias in how the proposal reviews happen
Speaker 1 00:13:02 To guarantee proposals are selected solely on scientific merit. T S E I implemented a dual anonymous peer review system. They now S strip the names of the principal investigator or PIs from the proposals, meaning the committee does not know the proposal's identity. It was first introduced for Hubble cycle 26. And since then, the implementation has significantly lowered the gap in success rates between projects led by men and women. Additionally, it's led to a higher success rate for faculty at smaller colleges. It
Speaker 6 00:13:32 Also changed the demographic of the PIs themselves. So because, you know, a track record was taken to account. It tended to have senior astronomers as the PIs for the proposals. Whereas since that's no longer a consideration now, you know, more students and postdocs early career people would apply. And we've seen that their success rate has also gone up as well. So it's really changed the demographic
Speaker 4 00:13:58 NASA send observers to make sure that the committees were following instructions. And we're not trying to use inside information. Like I know who wrote that proposal, that sort of thing.
Speaker 1 00:14:07 Again, that's Dr. John Mather. After the final project proposals are selected St S C. I sends the complete list of approved observation to targets over to the web team at NASA. It's now up to Dr. Mather and his team to assemble the schedule for cycle one.
Speaker 4 00:14:22 Now that we've got the long list, uh, of targets that people wanna look at and their pre preferences about when to look at them. Now we have to get a schedule. So when somebody has to build this giant calendar, according to the list of targets, and it's a pretty good, long and complicated process,
Speaker 1 00:14:37 This part of the process may be the most critical parts webs operation, to understand why we need to take a moment and consider what web looks like fully deployed. Imagine a sailboat suspended sideways in midair, the bottom of the ship, the part that's now vertical is webs 70 foot long sun shield. The perpendicular mast in sail is web's gigantic mirror gathering light as the telescope orbits around the sun. NASA constantly rotates. We so that one side of the sun shield always faces the sun earth and moon those objects and MI their own heat and energy waves with those light beams blocked that side of the sun shield provides shade for the telescope so that the delicate instruments on board don't melt.
Speaker 4 00:15:21 It's actually very clever. We have wheels that spin inside the observatory. And if you want the observatory to turn to the right, you make the wheel inside the observatory, turn the left, the wheels, push on the observatory. And then when you get where you're going, you stop doing that.
Speaker 1 00:15:35 There's only one drawback bringing a 70 foot brick wall with you into space means you're gonna have a tough time seeing through it. Web can only ever observe the parts of the sky that are visible facing away from the center of the solar system. That's about 40% of the full sky at any given moment. Now, this would be bad if web stayed frozen in space time, but because web is in constant orbit around the sun, this means that different parts of the sky are constantly entering. Web's 40% visible frame of view. This gives web access to 100% of the sky, just over a six month period. It's sorta like a gift that moves super slow and takes half a year to repeat. You're gonna see all of it, but it's just gonna take some time.
Speaker 4 00:16:19 Some things you just can't see today, they're in the wrong place. In this sky. We're expecting something like 60% of the time will actually be receiving photons from the sky that matter to science.
Speaker 1 00:16:30 After they receive the proposals from S St S CI Mather and NASA, take a broad look at what the proposals are trying to accomplish. They look for overlaps in the distribution of targets and see if there's any clumping of them in certain parts of the sky. They also consider the varying time constraint, windows, and the instruments that need to be used in the observation that
Speaker 4 00:16:50 Takes a long time to go. As I say, zipping around on the sky from place to place the telescope doesn't turn that quickly. And when it does turn, it doesn't settle down that quickly. And that's something to manage.
Speaker 1 00:17:02 NASA plugs the data into a computer. They also input the project information for other observation approved programs. This includes the early release science program that's designed for the public use and project designed to calibrate web the computer then makes different statistical models for schedule one Mather's team. Then selects the best one.
Speaker 4 00:17:21 We have planning tools, uh, basically set out. This is the best time of the year to do this particular target, a generalization of what they call the traveling salesman problem in mathematics. How do you go most efficiently from place to place? Even a one minute picture is very valuable. So when we choose all the list of targets, we want to go zipping around the sky. As much as we can not gonna waste any time going from place to place
Speaker 1 00:17:46 NASA updates, the schedule weekly, they run a validation program and check whether things are running according to schedule. If there's a surplus of time, they may add an observation target, vice versa. If they're running behind,
Speaker 4 00:17:58 We send up a sort of daily list and we actually made a change from the way they do it with a Hubble space telescope, with a Hubble, they say at this particular time of day, you're going to do, and the way we do it on the web is, um, after you finish this one, go onto the next one. How about orbits around the earth? Every, what is it? 90 minutes or 95 minutes. I forget. It's really quick, sort of a clock that controls everything, uh, in a LaGrange point orbit around L two. There's nothing to make you stop. So you can just keep on going until you've got job done.
Speaker 1 00:18:29 When it's finally time to observe web uses its onboard navigation system to first orient itself.
Speaker 4 00:18:35 So we have star cameras and there are three of them and they look at different, uh, parts of the sky and they recognize the star pattern out there and they send a computer signal to the computer that says, I know where I'm looking. And you say, well, that's not exactly where I wanted to look do this. And then we send the commands to the wheels to turn
Speaker 1 00:18:52 From here. It's really no different from looking through a telescope in your backyard. There's a few more robotic parts, but honestly, it's the same overall idea.
Speaker 4 00:19:00 Then we have another thing called a fine guidance sensor, which is a little camera right down there with the instruments at the, uh, effectively, the end of the telescope, where you would put your eye. We put the equivalent of crosshairs and a computer camera, and we say, okay, uh, tell me how far off the right spot we are. And we'll use that to send a command to the rest of the observatory to move until we're at the right spot.
Speaker 1 00:19:22 Afterwards, web sends the observational data down to earth and array of huge radio antennas receives the info. Those Hannahs are a part of NASA's deep space network. The data then gets forwarded to St S C in Baltimore, who then uploaded to their online database, called the McClusky archive for space telescopes masked for short, the project investigators can then log onto masks and download the data after that investigators like Dr. Chan and Dr. Kopa finally able to begin work unraveling the universe, but that's for the future for when web is calibrated and ready for research. Currently, the team is busy focusing each of Webb's 18 mirrors. They're about one month into the three month long focusing process.
Speaker 4 00:20:07 We allocated, uh, six months to go through the entire process of setting up the telescope. We're actually planning to begin observations at the end of June
Speaker 1 00:20:16 Mather and his team at NASA are still finalizing. The schedule web for right now is just sitting pretty.
Speaker 4 00:20:22 We have survived the hardest parts we, we got into space. Everything that we've tested is working all the movements, the deployments, they all functioned. We're not aware of anything. That's really not right. I am just really pleased that it has behaved itself as we hoped it would
Speaker 1 00:20:37 Dr. Chen and S St S C. I will announce the call for proposals for JWST cycle two, sometime after cycle one commences. At that point, the entire process happens again, the proposal writing the vetting, the scheduling, the world awaits web and its initial round of discoveries. Exactly what web will discover is a prediction based in hope and what ifs more than in educated guesses. If there's one certainty with web it's, this, the telescope means so much to the community of astronomy.
Speaker 6 00:21:08 So astronomy is really one of those very observationally driven endeavors in which like sometimes you just discover things that are totally unanticipated and it changes the way that you look at the universe. I think that's the thing that I'm looking forward to the most.
Speaker 5 00:21:24 I first came to observational astronomy in 20, and then even then I kind of knew I wanted to do nucleosynthesis. It almost seems like in some sense, I've come full circle back to that, like understanding the origin of the elements. That's one of the most exciting parts about like being involved in this project
Speaker 4 00:21:42 A long time ago. We couldn't say, well, I have a story to tell you. And here's what it looks like. Now we can say, I have a story. I think the universe works like this, and we can make you a movie, which is beautiful. The supercomputer people, the same kinds of people that can make the weather movies for you. They can simulate the early universe and how it grows into galaxies. And it is a beautiful, beautiful movie to watch. We're gonna learn things that never could have learned, uh, from combining computer tools with. So when we make a movie that matches the pictures we get with the web, maybe you can be able to say, I think, I believe now
Speaker 1 00:22:16 For w Nur news I'm.
