Planetary Radio • May 27, 2020

Celebrating 30 Years of Hubble with Astronaut John Grunsfeld

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John Grunsfeld

Board of Directors of The Planetary Society; President and CEO of Endless Frontiers Associates

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Bruce Betts

Chief Scientist / LightSail Program Manager for The Planetary Society

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Mat Kaplan

Senior Communications Adviser and former Host of Planetary Radio for The Planetary Society

Former astronaut and NASA Associate Administrator John Grunsfeld is often called the Hubble Repairman. He made three space shuttle trips to the space telescope to repair and upgrade it. Now he looks back over three decades of science, beautiful images, and inspiration delivered by the HST. Rubber asteroids are back, and you might win one in the new What’s Up space trivia contest.

John Grunsfeld STS-125
John Grunsfeld STS-125 View of STS-125 Mission Specialist 3 (MS3) John Grunsfeld posing for a photo near Atlantis' airlock hatch during the first session of Extravehicular Activity (EVA1).Image: NASA
Cosmic Reef
Cosmic Reef In this 30th anniversary Hubble portrait, the giant red nebula (NGC 2014) and its smaller blue neighbor (NGC 2020) are part of a vast star-forming region in the Large Magellanic Cloud, a satellite galaxy of the Milky Way, located 163,000 light-years away. The image is nicknamed the "Cosmic Reef," because the nebulas resemble an undersea world.Image: NASA / ESA / STSci
The Hubble Space Telescope
The Hubble Space Telescope View of Hubble captured by astronauts from the space shuttle Columbia during mission STS-109, March 2002. The astronauts installed new solar arrays as well as the Advanced Camera for Surveys and repaired the NICMOS instrument.Image: NASA / ESA

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Trivia Contest

This week's prizes:

What Stars are Made Of: The Life of Cecilia Payne-Gaposchkin by Donovan Moore and Jocelyn Bell Burnell, and a Planetary Society rubber asteroid.

This week's question:

Who is scheduled to be the first non-American astronaut to launch on a SpaceX Crew Dragon spacecraft?

To submit your answer:

Complete the contest entry form at or write to us at [email protected] no later than Wednesday, June 3rd at 8am Pacific Time. Be sure to include your name and mailing address.

Last week's question:

Approximately how many days did LightSail 1 spend on orbit?


The winner will be revealed next week.

Question from the May 13 space trivia contest:

Who is the Northrop Grumman Cygnus cargo spacecraft NG 13 named after?


The Northrop Grumman Cygnus cargo spacecraft NG 13 was named after first African-American astronaut, Major Robert Lawrence.


Mat Kaplan: The astronauts known as the Hubble repairman marks the telescopes 30th anniversary this week on Planetary Radio. Welcome. I'm Mat Kaplan of the Planetary Society, with more of the human adventure across our solar system and beyond. The Hubble Space Telescope has just completed three decades in space. Its accomplishments have far exceeded even its most optimistic creators. One of those accomplishments is how the beauty and wonder it has revealed, have thrilled and inspired hundreds of millions of earthlings. We'll review its life so far with the man who visited it three times, the astronaut who would later become NASA's Chief Scientist, and who is still using the Hubble in his research today.

Mat Kaplan: For all of its successes, the Hubble has yet to find the fabled rubber asteroid. But, we have one waiting for the winner of this week's What's Up's space trivia contest along with a great new book. This week's biggest space story is in last Friday's edition of The Downlink. As I record this, we are still a few hours away from the launch of a Space X crew dragon on Demonstration Mission II, the mission that will take Bob Behnken and Doug Hurley to the International Space Station.

Mat Kaplan: Like most of you, all of us at the Planetary Society will be watching and holding our breath as the Falcon 9 rocket sends them soaring. That WFIRST telescope is no more. No, not canceled, but renamed the Nancy Grace Roman Space Telescope. Roman passed away in 2018. She led an effort back in the 1960s to envision how telescopes in space could advance research. The naming would appear to be a good sign for the troubled project. The Trump administration has tried to cancel it in each of the last three years. We've got more information at

Mat Kaplan: The James Webb Space Telescope is the more immediate follow on to the Hubble. The JWST's giant multi-segmented mirror has been folded up into the configuration that will allow it to fit inside the payload nose cone of the rocket that will finally, we hope, carry it into space next year. We now know that OSIRIS-REx will make its first attempt to collect a surface sample from asteroid Bennu on the 20th of October this year. The spacecraft and its samples will return to earth in 2023. There's much more to enjoy in The Downlink, this and every week you'll find it at, and the subscription is free.

Mat Kaplan: I've now hosted three live online events for Explore Mars, the Washington DC based nonprofit that shares the Planetary Society's goals for the red planet. You may have heard mine delicious conversation with astrobiologist Penny Boston and NASA Chief Scientist Jim Green. I'm back this week with audio excerpts from the third of these events, and it features a former NASA chief scientist. The audio quality is once again not quite up to our usual standard, but I think you'll enjoy my recent long conversation with John Grunsfeld. You'll hear John refer to some slides he presented. I've kept these references because, I think they work just fine in this format. You can watch the video of the complete event at Here's Explore Mars CEO Chris Carberry getting the show underway.

Chris Carberry: I'd like to introduce our panel, Mat Kaplan and John Grunsfeld. Welcome gentlemen.

Mat Kaplan: Thank you Chris, very much. It's likely that there isn't another man or woman who knows more about the Hubble Space Telescope than John Grunsfeld. It is certainly true that no one has done in space more with this most famous scientific instrument of all time. He is an astrophysicist who has taught and conducted research for some of the finest institutions on our planet. He flew on five, count them, five shuttle missions. Three of these were dedicated to maintenance and upgrade of the Hubble or HST. He spent more than 58 hours outside in extra vehicular activity. Later he would become NASA's Chief Scientist, and then the agency's Associate Administrator for the Science Mission Directorate. This meant that he had responsibility for well over $5 billion worth of missions projects and research.

Mat Kaplan: He finally retired from NASA four years ago. That was also when I met John. It was at the Annual Space Symposium in Colorado, where we compared space ties. John, I know that you have some great slides that you want to share with us. I want to confirm something first. Is it true that you were the last person to touch the Hubble?

John Grunsfeld: Well, that's a matter of great debate because of course I was wearing gloves on my human space. I'm wearing gloves today as a matter of fact. Apparently, that's my normal attire. I'm not wearing a tie today. So, you won on the tie department. But, Megan McArthur claims to be the last one to touch the Hubble because, her job on board was robotic arm operator. So, she touched everything with the shuttle robotic arm, and of course we did have to deploy the Hubble. But, it is true that as far as as human hands, at least in gloves, I was the last person to touch the Hubble.

Mat Kaplan: Well, whether it was through thick pressurized gloves or not, I think you have described yourself as a telescope hugger.

John Grunsfeld: I am one of many Hubble huggers over the years. This year, we're celebrating quite the milestone. This is the 30th year of Hubble being on orbit. It was launched in 1990, April 24th, 1990 was the launch of Hubble. So, we're just slightly over 30 years. It's still a milestone. Very few observatories, very few satellites make it to 30 years on orbit. It's a Testament to the incredible designers, the people who designed the Hubble Space Telescope and the policy people who had the insight to make a serviceable observatory. Hubble is still basically state-of-the-art on orbit and doing breakthrough science, because we were able to go up and put new scientific instruments in and fix things that break. Otherwise, Hubble would no longer be viable now. So it's a pretty incredible story. Optimal marriage of human space flight and science, robotic spacecraft, to be able to allow Hubble to unravel the mysteries of the universe.

Mat Kaplan: So serviceable, designed to be serviceable but not always in the most easy way as I bet you will get to. if You don't in your slides, we will later because, sometimes it could be quite a challenge as we've heard from you and others who completed that spectacular work on the Hubble Space Telescope, and made sure that it is still able to do great science for us today. Why don't we go ahead into your slides and then we'll follow that up with questions more from me and some from our viewers.

John Grunsfeld: Chris Carberry, thank you very much for inviting me. Chris did try one of those repairs that Hubble was not designed to do, a repair that we had to do. I think that's a very important thing to bring out right from the start is that, what we've learned from repairing and upgrading the Hubble Space Telescope is, just about anything that you can do on the ground, we can learn how to do in space. It may be a little bit harder in a space suit, but people are really good tool builders and we figure out a way to do it.

John Grunsfeld: When we go to Mars, we're going to have to really exercise that a lot because, Mars exploration presents challenges that we cannot anticipate now. The fact that we could do these difficult repairs on Hubble, I think bodes very well for human exploration.

John Grunsfeld: I do want to, at Mat's urging though, mention that human exploration and the first American to orbit the earth was John Glenn. He was just a tremendous guy. He had two space flights, one on mercury that we're all very familiar with, and of course at the age of 77, he flew on the space shuttle. That mission actually carried some hardware that was a test flight for our Hubble mission in 2002. Fortunately, he lived a very long and productive life, both serving as an astronaut and serving as a public servant. But, behind John Glenn, and I think responsible for, and John I think would agree with this completely, responsible for a significant fraction of his success in life, was his wife Annie. Annie was just absolutely the most wonderful person you could ever imagine. Stood up to John when, when she wanted to, and it was frequent. He had just ultimate love and respect for Annie as a human being. Sadly, she passed away today at the age of 100 years, which is pretty incredible. Very, very strong woman. I think we should all give her a salute here today.

Mat Kaplan: Thank you, John. Thank you for that tribute.

John Grunsfeld: We can only hope Hubble lives 100 years, but 30 isn't too bad. This is the 30th anniversary picture. One of the traditions of the Hubble Space Telescope is, every year, the Space Telescope Science Institute, which manages the Hubble Science Program and operates the Hubble Telescope, produces an anniversary image. This one's called cosmic reef. This looks like, if you look actually down on earth, the coral reefs, they have an amazing green blue hue. This is a star forming region in the large Magellanic cloud. In the Northern hemisphere here, we don't get to see this. If we have any sky watchers in the southern hemisphere, this is a familiar object but probably not in quite this glorious detail.

John Grunsfeld: This is a stellar nursery and it's been lit up by very hot stars that have just turned on so to speak. It's just really a beautiful image. I think this image and many other Hubble images, highlights the value of the Hubble Space Telescope, which is amazing science. From images like this, we learn about star formation, about stellar evolution. We learn about how material goes from the inside of stars into clouds and then to reform into stars, the lifecycle of stars. How planetary systems form, because we learned studying in detail is that, when stars like this form, the stellar material circling that star forms at about the same time, and planets form at about the same time. So, incredibly scientifically rich.

John Grunsfeld: But, it also shows something that before Hubble we didn't really I think appreciate, which is that the universe is a more beautiful and dynamic place than we ever imagined. This could be a piece of modern art that would sell for hundreds of thousands of dollars at an auction. But yet, this is nature and we see this all over the universe. The Hubble has been the primary mechanism by which we have been able to show people around the world the wonder and awe of the universe, the beauty and richness in the universe.

John Grunsfeld: 11 years ago, I was on orbit on the space shuttle with my crew, and one of the items we got to bring with us was a replica of Galileo's telescope. It just shows that in a roughly 500 years, how far humanity has come from somebody taking a telescope, Galileo and observing the skies with it, to the Hubble Space Telescope and being able to build a space shuttle to go up to space to be able to service that Hubble Space Telescope, and how much we've learned. I mean, it's really incredible that just in the last 100 years, from Edwin Hubble observing on a 100 inch telescope to the Hubble Space Telescope, which has only about 94 inches across, that we've been able to put together a story of the origin of the universe, the big bang, to the expansion of the university, to the formation of galaxies, of black holes, of planetary systems all the way through the formation and evolution of the earth in just 100 years is pretty incredible using observatories like the Hubble Space Telescope.

John Grunsfeld: The Hubble Space Telescope is not a particularly large telescope by astronomical standards. It's 2.4 meters across. It weighs about 25,000 pounds. But by being above the atmosphere, we get a clear view of the universe. The atmosphere makes things look fuzzy, because atmosphere is moving. As well, certain types of light, ultraviolet light for instance, don't make it down to the surface of the earth. So, we just can't see it. There aren't ultraviolet telescopes on mountaintops, because the ultra light doesn't make it through our atmosphere.

John Grunsfeld: So, the Hubble's perch in orbit gives it an unfair advantage over big telescopes on the ground. But that's okay. They work together for us to learn about astronomy. We use the word Hubble as a superlative. So, when we talk about the Hubble of particle accelerators or the Hubble of cars or things like that, we mean the best thing possible. Using that word though, we forget about Hubble's, its infancy when it first got to orbit. This is one of many cartoons that appeared early in Hubble's history. It says, "First photos from the Hubble." There's a picture of a distorted moon, it looks like a peanut, Jupiter, Saturn. Then, if you were to turn the Hubble down on the ground, you would see very angry taxpayers.

John Grunsfeld: That's because when Hubble was launched and they took the first images, astronomers realized that something was horribly wrong. It was determined pretty quickly that the mirror had something called spherical aberration. What that means is that the prescription of the mirror, think of wearing glasses, was slightly incorrect and the images were fuzzy. Fortunately, by interrogating images, astronomers and optical engineers were able to figure out what that wrong prescription was and fix it. So, on the first servicing mission in 1993, the crew brought up contact lenses in effect. In fact, they were mirrors, but that doesn't matter. The mirror corrected the spherical aberration. Ever since then, we think of Hubble as the greatest thing ever.

John Grunsfeld: As I said, 11 years ago, I was on orbit with this crew. The crew is commanded by Scott Altman. It was his fourth mission. He's an aerospace engineer and a Navy captain. He had flown also with me in 2002 to the Hubble Space Telescope. So, he was a Hubble veteran. To his right is Megan McArthur, it was her first flight. She's an oceanographer and an astronaut obviously. She was our robotic arm operator and flight engineer. Of course, to her right is myself on my fifth mission, my third mission to the Hubble Space Telescope. My space walking partner, Drew Feustel to my right, was on his first flight. He's a geologist, exploration geologist. He's still active in the astronaut corps, and returned last year from the International Space Station.

John Grunsfeld: To Scott Altman's left is Greg Johnson, an aeronautical engineer and also a Navy captain. He is now at Blue Origin and he was our pilot. To his left is Mike Good, Air Force Colonel, a flight test engineer on his first flight, also at Blue Origin now. He was a space working partner with somebody you probably have heard of, Mike Massimino, Astro Mike if you follow him on Twitter. He was on his second flight. He flew with me as well in 2002. So, we had a mix of Hubble experience and first time flyers, but you wouldn't know it on orbit. Everybody did just really well getting to orbit, training and fixing the Hubble.

Mat Kaplan: Much more of my live conversation with former astronaut, NASA Chief Scientist and Associate Administrator, John Grunsfeld, is only about a minute away. But, we need to take that minute to talk one more time about the sponsor who's helped make it possible to present this week's episode of Planetary Radio. Today's program is once again brought to you by Athletic Greens, the all in one daily drink to support better health and peak performance. It can be difficult to cover all of your nutritional bases, that's where Athletic Greens will help. Their daily drink is like nutritional insurance for your body that's delivered straight to your door. I've been enjoying Athletic Greens for weeks now. Some of my friends and family are still amazed to hear me say this. I try to get them to try a taste so they'll be as happily surprised as I was. I also heard from a listener who worried about whether it contains everything it claims and nothing it shouldn't.

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John Grunsfeld: We first had to launch, this was the first time I'd been on a day launch. All my previous four missions had been night launches. So, that was a different experience. But still, the ride to orbit is incredibly dynamic. Really, a pretty exciting thing to do. We flew after the tragic loss of Columbia. By not going to the space station, and we didn't have a rescue option to hang out at the space station. So, there was actually a second shuttle on the other launchpad just in case something happened, theoretically they could come to rescue us. I think mostly it was to show that NASA was doing something just in case something went wrong, rather than just ignoring the risk. But nevertheless, we had that in the background.

John Grunsfeld: Of course, once we got to orbit safely, they turned that around to prepare it for the next station mission, as we were safely on orbit. Once we got to orbit, we had to chase down the Hubble Space Telescope. Next slide. So, here's Scott Altman actually manually flying the space shuttle up underneath the Hubble Space Telescope as we got closer and closer. His job was to get us right next to the Hubble, and with the shuttle basically motionless compared to the Hubble Space Telescope, so that Meghan McArthur, next slide, could reach out with the robotic arm and grab the Hubble.

John Grunsfeld: What I find really fascinating sociologically is, when I trained on the robotic arm, we actually have a large hydraulic arm in Houston that I could drive around and practice with. When Megan trained, we had switched everything to computer simulators, meaning basically she trained how to grab Hubble in a computer game, did it over and over again. So, when we got to orbit, it was the first time she got to fly the robotic arm to grab the Hubble Space Telescope. This would, pick your number, $8 billion international resource, exploring the universe, one of a kind.

John Grunsfeld: If she bumped it accidentally instead of grabbing it, it would go floating off and we probably wouldn't be able to get it back, just from safety and power and other things. So, she had a lot of focus and she did a great job, successfully grabbed the Hubble Space Telescope. With that, we put the Hubble into the payload bay of the shuttle. The next day, we were ready to do our spacewalks. This is what I really love, to get into a space suit and go outside. I think you can see hopefully, that I have a big smile on my face. Anytime I'm outside in the space suit and almost all the time in space, I have that silly grin on my face because it is just so special.

John Grunsfeld: Here, if you look in my helmet, you can see the earth reflected in my visor. Behind me is the space shuttle wing. To the left is some of the gear that we bring up to service the Hubble Space Telescope, and the amazing space suit. The space suit is really a full spaceship in itself. In the backpack, of course there's oxygen, there's a backup oxygen supply, there's batteries, there's a little canister to absorb carbon dioxide as I exhale. Of course, the helmet, the helmet has cameras, people inside the shuttle and on the ground can see what we're looking at and working on. There's helmet lights with high and low beams. The batteries are so good now, we just leave those on all the time.

John Grunsfeld: In front of me is my tool belt. Everything on that tool belt has to have a tether, because if a tool floats away, that'd be really bad, not to mention that you wouldn't have the tool to fix something, but eventually that's going to reenter and you wouldn't want it to hit that high flying airplane, we call the International Space Station. So, we were trained if we let go of a tool to say, "Look out below."

John Grunsfeld: But fortunately, on none of my Hubble missions and we really trained this hard, we didn't lose a single tool or object. One of the reasons I was so happy is, on this first spacewalking day, our job was to change out the wide field camera 2, that was put on in 1993, and replace it with the super duper wide field camera 3. It sounds like one upgrade but widefield camera three incorporates the best detectors, the best cameras that were available in 2009, and in fact are still pretty much state-of-the-art. It had two channels, a visual channel like what we see and an infrared channel. So really, a major advance for Hubble. Something that really promised to explore new realms.

John Grunsfeld: One of the easiest tasks that we do on Hubble, I mean, there were two bolts you loosen, you pull it out, you put the new camera in, you tighten the two bolts and you're done. So, I was pretty happy that we were heading out to go put in this new camera, revolutionized astronomy. When Drew went to loosen the bolt, he couldn't get it loose. It was too tight. We really sweated that for a long time. I was thinking, "This is the one time I've been out space walking and I was not smiling." I thought, "I cannot believe we came all this way." The Hubble Project was canceled, but we got it back, we survived launch, we got to orbit, and now we can't get the old camera out.

John Grunsfeld: Fortunately, the ground gave us the go for Drew to apply a little elbow grease beyond what torque was normally allowed, and he was able to loosen the bolt. But, it was tense for a little while. We also replaced the optical correction device. I talked about contact lenses, COSTAR instrument, which is the Corrective Optic Space Telescope Axial Replacement. COSTAR's a much easier way to say it, that had those contact lenses. So, it wasn't quite as simple. But, we were able to remove that because all the new instruments have that correction incorporated into their own optics.

John Grunsfeld: So, we were able to take that out and put in a new instrument called the Cosmic Origins Spectrograph, which is up on orbit now working great. You can also see that Drew has a Death Ray Laser on his side, his sidearm, that thing with the lung tube as part of space force investigations early on. But actually, that's a power tool. That's basically a power screwdriver. It's something that Hubble Space Telescope Project pioneered. It's not widely used on the ground. It's called the align tool or wire tool. But, that's our general purpose screwdriver wrench. It's used on basically every station spacewalk now. So, Hubble has been a pioneer for space tools as well.

John Grunsfeld: The other thing you notice is, that box looks very big and it is. It weighs about 800 pounds. So, I convinced Drew to go to the gym every day for a year to lift weights, so he'd be able to lift that thing, which is pretty silly because it's free floating as is everything. So, it has no weight in space. But in fact, it does have mass, not Mike Massimino, but it has physical mass. You have to be very strong in the space suit to be able to handle big objects like that, because one, the space should provide a lot of resistance just to do a bicep curl or something. It's like lifting a 30 pound barbell if you get a big box like that moving too fast, you've got to be strong enough to stop it or it'll slip right out of your hands. When things move very slowly, but you have to be pretty strong. So, spacewalking is actually very much an athletic event.

John Grunsfeld: We also put in a new fine guidance sensor. We changed the batteries on Hubble, we changed the gyroscopes, we changed some thermal insulation, all kinds of upgrades and repairs to the Hubble Space Telescope, such that when we left it in 2009, Hubble was not only state-of-the-art in terms of scientific instruments, with all of the instruments working it was also upgraded so that it would have hopefully a very long lifetime. Now, our warranty was five years, labor included, and that expired quite a long time ago. But, I'm happy to say that everything on Hubble is working well and we still have a full compliment of working gyros. Knock on wood, Hubble can last another five or 10 years on orbit.

John Grunsfeld: So, once we were done playing outside, Megan was able to grab the Hubble again, lift it out of the payload bay, everything working, everything fixed and let go of it, so that we could back out from underneath it with Scott all at the controls. So, we saw Hubble drifting off into the distance behind us, getting smaller and smaller until we couldn't see it anymore. Hubble has been on its journey ever since. The question is, did we fix the Hubble or did we break the Hubble? This is just an example that says we fixed the Hubble. This is an image that's called the Hubble Ultra Deep Field. You've probably seen a picture called the Deep Field, but the Ultra Deep Field is with this new camera. Other than a couple of stars that are in our own galaxy, and you can see those because they have the little crosses, diffraction patterns coming out from them, I see two stars in this image that are in our own galaxy, everything else in this picture, every spec that you see is a whole galaxy with tens to hundreds of billions of stars.

John Grunsfeld: The original Deep Field picture, Hubble could see about 3000 galaxies, there were over 10,000 galaxies in this one picture. This picture is smaller than your pinky if you were to hold your pinky at arms length up at the sky, your pinky nail, this picture is an area of the sky smaller than that. So, it's really incredible when you think about here we are on planet earth orbiting a rather ordinary small star, very quiet star, in a solar system with eight plus one planets. That one star in our galaxy is one in 400 billion in our extended galaxy. There are just billions and billions of other stars and galaxies out there. Think of how many other earths are out there. It's just mind boggling. There must be many.

John Grunsfeld: A little closer to home, when I was growing up, one of my favorite constellations was the constellation Orion. If you look at Orion, it's easy to identify Orion's belt with three stars. Then, there's a sword that are three stars. But actually, that middle star in the sword is not a star at all. It's the star forming region, a very bright region of gas and dust, where some of that gas and dust is collapsing and baby stars are being born. This is what it looks like through the Hubble Space Telescope. Again, this looks like an amazing abstract art creation maybe from an airbrush artist, but this is in real nature. This is what it would look like if you had the sensitivity of the Hubble Space Telescope, and a little bit wider spectrum that our eyes could see. We've been able to study this in great detail, to look at stars that have just turned on from collapsing gas and dust, until it heats up enough, the fusion starts.

John Grunsfeld: Of course, the Hubble doesn't just look at distant things. It also looks at close things. This is a series of images that were taken by the Hubble stacked on top of each other. We have captured in each of those images, the moon of Mars Phobos as it moves along in its orbit. But, it also shows us that we think of most planets as being very different from earth. But here, we can see that there's high level clouds on Mars. It just reminds us that Mars has, even though it's a thin atmosphere, has a carbon dioxide atmosphere that has a lot of other components, including trace amounts of oxygen and water vapor. These are not only carbon dioxide clouds but water clouds. We have actually seen snow on Mars from our Mars explorers. You can see that there's different weather patterns.

John Grunsfeld: Of course, this is the southern hemisphere winter. We can't see the solar ice cap at the south pole in this image just because of the angle. But, Mars is a dynamic planet with seasons and weather, someplace I'd like to go, and I know lots of you on the viewing probably would like to go to. Hubble has been able to study dust storms and weather and climate patterns on Mars now for 30 years, and we will continue to do so.

John Grunsfeld: What's up in the future? That's something we'd all like to know. One of those things that's getting closer to launch, we're now about a year from launch, is the James Webb Space Telescope. It's going to be amazing observing Mars. That's going to be just really incredible, and the rest of the universe. I wanted to put in a plug for James Webb Space Telescope. I think all the pieces have been put together and they're buttoning it up, getting ready to send it to the launchpad for launch on Orion Five next year. There are some interruptions due to COVID-19, but hopefully we get off next year and we can start observing soon thereafter.

John Grunsfeld: That's the Hubble story. The Hubble Space Telescope is still very much alive. The story is still evolving. I like to say that perhaps the most incredible discovery from the Hubble Space Telescope, hasn't been made yet and will be made in the future. So Mat, over to you.

Mat Kaplan: Thank you John. The science that is still being delivered by the Hubble, I mean we could spend not just this hour but hours and hours going through thousands of iconic images. I mean, I've been in the office of a Senator who had the deep field on his wall. Everybody knows the towers of the pillars of creation, right? It's endless and they're all gorgeous. It says something about I think, not just the contributions that the Hubble has made to science, but also to the public's appreciation of science. I mean the public around the world, not just in the United States. Did everyone realize how important Hubble, the contribution that it would make in that area as well, that it would become, as I said, probably the most famous scientific instrument of all time?

John Grunsfeld: I don't want to make it sound like a cult, but Hubble really may well be by almost any metric, the most productive scientific instrument humans have ever created today. Again, I credit the amazing engineers who designed it. The ability of an astronaut to go up and service it, that longevity has allowed us to unravel the mysteries of the universe as much as it has. I don't think it was well appreciated how Hubble would share that wonder and awe of the universe with the general public. That's because before Hubble, we didn't really know how beautiful the universe is. We hadn't had that experience. The best images on the ground did show incredibly colorful, fuzzy objects.

John Grunsfeld: But, it's when you have the resolution of the human eyeball or better on the universe that you start to go, "Wow, that's really beautiful. That has depth that inspires us to think about the universe we live in, in a way that we never thought before." I think most people before that thought, "Yeah, the universe filled with stars, little points of light and some planets." The planets are interesting but not the beauty that we see with the Hubble Space Telescope.

Mat Kaplan: With all of that work you did for NASA, I mean, you followed that with a stint at another organization that everybody knows the Hubble, but they may not know one of the organizations behind it. The Space Telescope Science Institute, where you were Deputy Director. Could you say something about what the Institute does, and the role it's played not just with the Hubble, but with many telescopes above our heads, a lot of other great observatories?

John Grunsfeld: Absolutely. In fact, that's the incredible vision of a man named Riccardo Giacconi who was the person who really put together with a team, the concept of having an institute dedicated to operating a great observatory, the Hubble Space Telescope, but providing support for the scientific community to use the telescope. The traditional model is, whoever can get the most money together builds a telescope, and the people who are at the institution like the University of California or Caltech or someplace like that, they get to use the telescope, and if they're really nice, they let other people use the telescope.

John Grunsfeld: The Hubble Space Telescope has been called the people's telescope. Almost anybody in the audience today can propose to use the Hubble Space Telescope. The challenge is, if you have to learn how to operate the instruments on the Hubble and calibrate the data and remove the effect of cosmic rays and understand how to command and what filters to use and so on, the technical detail, it would be very challenging. So, Riccardo Giacconi's vision was, that there would be a group of people and they called it the Space Telescope Science Institute, that would operate the telescope and would also support users by performing those calibration activities, removing the cosmic rays, fixing the defects and the detectors, all the behind the scenes stuff that's really very tedious, and would have to be replicated over and over and over again by every scientist.

John Grunsfeld: Instead, the Institute provides the research support so the astronomers can concentrate on the science. This was at the time revolutionary and there was a lot of pushback, and it took a lot of convincing and was done long before the telescope was launched. So, it was a grand experiment. Build a telescope that anybody can propose to use in a research institute, to support those scientists and has been an extraordinary success. It's one of the reasons why Hubble produces more than two scientific peer reviewed publications a day, because the scientists can concentrate on the science. So, if myself as an observer, personally, I'm using the Hubble Space Telescope on a project with Bill Sparks at Study Institute, to observe plumes of water around the moon, Europa around Jupiter, with the Hubble Space Telescope. If we have a technical question, we call up one of the supporting people and they help us solve it. We don't have to figure it out on our own.

John Grunsfeld: So, the Space Telescope Science Institute was that experiment extraordinarily successful. It will also be used to control and manage the science program for the James Webb Space Telescope. But because of its success, it was also replicated for the Spitzer Infrared Telescope. At IPAC at Caltech, they have a mini Space Telescope Science Institute. When the Europeans decided to build the most powerful ground-based observatory ever called the VLT, it's actually four telescopes that they operate in the southern hemisphere, they built a telescope institute to manage that the same way of the space telescopes. So now in Europe, observers don't have to learn about how to use the telescope. They propose for the time and select it, and they have people down at the telescope who form the observations for them, although they can go, and help them with all of these instruments.

John Grunsfeld: The Atacama large millimeter array, a radio telescope uses that model. That's been replicated now, and is the standard model for how to do science, at least in the astronomical realm. Very often, there are studies done to try and replicate that. For instance, the case systems for the International Space Station, they tried to build a model like that. It's such different science and different application. It's had a lot of troubles, but people try and replicate now the Space Telescope Science experience elsewhere, because of its great success.

Mat Kaplan: Definitely a part of the Hubble's legacy along with the Institute itself. I've got just one more for you. You're an astrophysicist. You have often worked outside of the range of visible light in the electromagnetic spectrum and as you said, the Hubble goes a little bit into the infrared, a little bit into the ultraviolet. But, other instruments like Spitzer, and as far out as x-rays Chandra and cosmic rays. These advantages of working across the electromagnetic spectrum from space. This is just going to continue, right? I mean we're not... You mentioned JWST, but the future for astronomy from space in space is pretty bright, isn't it?

John Grunsfeld: I think folks talk about budget challenges and we can't do this mission and we can't do all the missions and that's true. But, I really believe that we are entering a truly golden age of astronomy and astrophysics in our knowledge of the universe. We do still have Hubble, we're about to launch James Webb Space Telescope. That opens up a whole new realm where we haven't explored very much yet, at the high resolution and in the spectroscopy and breaking the light into its component parts. So, James Webb will really be like having another Hubble in a new realm. But at the same time, we're opening up different areas.

John Grunsfeld: I think the Atacama large millimeter array, which is a radio telescope international project, is the Hubble of radio astronomy. The first light has already occurred, but the Daniel K. Inouye Solar Telescope on the Island of Maui in Hawaii, is the Hubble Space Telescope of solar astronomy and is going to give us the most detailed views of our own star, and teach us probably more about stellar astrophysics than much of what's happened because, now we can see things at the scale of the magnetic fields on the photosphere of the sun and study that.

John Grunsfeld: We're about to build something called the Large Synoptic Survey Telescope, that's going to scan the whole sky every few days, and is going to be able to look at transient phenomenon that we've never had access to, a full host of other observatories, the least of which is, we're now entering for the first time in human history, the realm of gravitational wave astronomy. The general topic is multi messenger astronomy. This is one of the things that Hubble pioneered, it's working with Hubble and Spitzer and Chandra, all of the great observatories, to put together the story about how things work in space. It's only getting better as time goes on.

Mat Kaplan: A bright future indeed. As you've demonstrated brilliantly, Hubble was built to be serviceable. We're getting questions from a number of our viewers, Patrick Harper, Andrew Planet, that I'll try and consolidate a little bit asking about like JWST, will it be serviceable? I happen to know, no it won't be, largely because it's going to be far away. But, do you in general see that as a lesson for the future, that we should be building these great instruments and other things in space? I mean, the ISS is an example so that humans can go out there and upgrade them and repair them?

John Grunsfeld: Well, I have a slight twist on that, which is yes. I actually think that when we invest billions of dollars into an observatory, not just a simple experiment, but something that's multipurpose and we want it to last a long time, then it ought to be serviceable. That decision on James Webb was made very early on. There are a number of reasons why that decision was made. One of which is, James Webb Space Telescope's going almost a million miles away from earth. It was imagined, well nobody could get out there.

John Grunsfeld: But, the other part of it is, it's a cryogenic telescope and very delicate. To be able to pass the mass of Hubble, you had to make a lot of trades in a very lightweight telescope. It turns out that, especially the sunshade the James Webb Space Telescope has, tend to block the sunlight and/or shine from the telescope so that it can cool down, is extremely delicate. So, if you were to try and approach it say with the spacial, which could never get out there anyway, but just the plumes from the little rockets that slows down, would probably because that sunshade to fold up and that would destroy the telescope.

John Grunsfeld: So, its inherent design is not serviceable and it was never intended to be. But, I think future spacecraft should be. In fact, Congress agrees with that. They actually put into an authorization Act of NASA, that future observatories, they have to consider servicing. As an example, the wide field infrared space telescope that's currently being designed, is being designed to be serviced, but not necessarily by humans. For simple things, robots are perfectly good at turning a bolt, removing something, putting a new object in and turning the bolt again. WFIRST will also be a million miles away near James Webb. So, it's perfectly appropriate that a robot could go out and put new batteries in or change out a scientific instrument or even better refuel it, so it has a longer lifetime.

John Grunsfeld: I think a combination of those modes is what you want. If something is dull or really dirty or very dangerous, let's send a robot. Robotics is making enormous strides. We're going to launch a mission, it was called Restore-L, now it's called OSAM-1, to go refuel a satellite in just a couple of years. It has robotic arms and it's going to demonstrate building things. I think we're going to see on orbit assembly and servicing take on a bigger and bigger role as time goes on, as we have more capability.

John Grunsfeld: Certainly, if we're going to go to Mars, we're going to want to assemble a spaceship first to go to Mars. So, we need how to learn how to do that as we did by assembling the International Space Station. On the outside of the International Space Station, we routinely use the robotic arm to replace components, with no spacewalking at all. The ground controls it.

Mat Kaplan: Of course, we're only a couple of months away now from the next smart robot headed to the surface of Mars, Perseverance. This is from Jesse, who's an 11 year old student in Virginia. Did John ever make a mistake in your maintenance of the work and upgrades of the Hubble Space Telescope that caused any kinds of issues? I mean, anything that ever happened up there that you kicked yourself about?

John Grunsfeld: So, there's two ways to answer that, and thanks for that question. If you look at the end of the Hubble Space Telescope, there's a little white dome on the very back of the telescope. That's called the Low Gain Antenna Protective Cover. It's a fiberglass cover. That cover is there so that if an astronaut is out space walking on the Hubble like me, if you bump into it, you don't damage the low gain antenna, which is very delicate. Actually on our mission, we did five spacewalks. Drew and I, were highly trained. We did three of those five spacewalks. We pretty much went through all three spacewalks doing everything we were supposed to do and a little bit more and we didn't make any significant mistakes.

John Grunsfeld: At the very end, the top of my helmet bumped into that antenna after I'd taken the protective cover off, and broke the tip off of it, which is another protective cover, which we grabbed the floating away tip. Drew captured that, but we had to go back out. I had to go back out and put that antenna cover on. I think it was destiny because, the manager, the people who manage the operations of the telescope, had to manage the temperature of that antenna all the time because it would overheat. When we put the protective cover back on, which was not intended to be left on the telescope, their thermal problems went away, because the outside of that cover is white, and now they don't have to manage that anymore. It really didn't affect the transmission at all. I think like Hubble reached out and wanted that.

Mat Kaplan: Well Jesse, we're only human and space is hard. Because we're human, we have the smarts and the ability to recover from things like this, as you just heard. Here's a question that came in actually before we started the hour from Mike Helton. He's wondering about preserving the Hubble, and why there isn't consideration for NASA to boost it into a higher orbit for storage for 100 years or more for future generations. Is there any thought about the distant future, hopefully distant future of Hubble when it finally is no longer operational?

John Grunsfeld: Well, like all satellites and low earth orbit and Hubble is orbiting about 600 kilometers above us, there is some atmospheric drag. So over time, Hubble will slowly spiral in to our earth's atmosphere. Its currently estimated, because our sun has been incredibly quiet, that sometime in the mid 2030s, there'll be enough atmosphere drag on the solar panels and on Hubble, that it won't be able to be an operable observatory anymore, even if everything is working on it. The atmospheric drag will cause enough disturbances. To cover that eventuality, inevitable eventuality, there is on the books a mission to Hubble, probably robotic, to install a de-orbit module, which a little rocket motor that will deliberately target Hubble into the Pacific Ocean, so it doesn't hurt anybody. There's no reason why you couldn't use that same robotic mission and motor to send a Hubble up to a much higher orbit. It wouldn't take much more altitude to put it in 1,000 or 10,000 year orbit. The atmospheric drag drops off very quickly. Then, it could be a museum piece in space.

John Grunsfeld: Now, that's not without risk. First of all, you're deferring the problem to later generations, but I hope our space exploration plans are such that space travel becomes routine by 10,000 years from now, given our progress to date. I thought we're in big trouble for other reasons. But, boosting Hubble does defer that problem to later. There's always the risk of a satellite-satellite collision. Hubble doesn't have any propulsion to move away from an oncoming object. Anything you leave in space is a potential problem from space debris and things hitting it. So, that is a concern, but there's no reason you couldn't boost it to a higher orbit. That's a policy decision.

Mat Kaplan: It'd be nice to see it sticking around as long as the pyramids for our descendants to a marvel at. There's one more that I want to squeeze in, because it's from eight year old Zoe in Colorado Springs who says, "By the time I'm a grownup and working with space telescopes, what kind of telescopes will I be working on if James Webb is then 30 years old?" She says, "Thank you John." What's way out there, beyond? What would you like to see 30, 40, 50 years away in space doing science for us?

John Grunsfeld: Well, thanks for that question Zoe, and in particular because, I grew up wanting to be a scientist, and then in high school wanting to be an astronomer. I assumed of course, that by the time I grew up, went to college, went to graduate school and became an astronomer, that all astronomers would go to space. It just seemed like, well astronomers go to mountain tops, but space is the place to be. So, I thought it would just be a natural consequence of me being an astronomer. Really surprisingly, it worked out for me, but it's not the norm. I hope for you that it will be, that space, although it will always be very dangerous, becomes more routine in the sense of access. Who knows? Maybe if we can boost the Hubble, Hubble will still be there.

John Grunsfeld: My vision, my dream is that after James Webb and the things we have planned now, we'll be bold and that we will decide to build a 16 or 20 meter telescope. By build, I really mean build. That robots and/or robots and humans will assemble it, because that's too big to put in a single rocket. That we will assemble a telescope that's big enough and it takes 16 to 20 meters. That we will be able to look at the nearest 100 or so sun-like stars, stars like our own sun, to observe planets around those stars that are in the habitable zone, and see if anybody's home. That takes a 16 or 20 meter telescope, much, much bigger than Hubble, a little bit bigger, two or three times bigger than James Webb.

John Grunsfeld: One of the things I'm working on now is the technology with others at Goddard Space Flight Center, at JPL, at various companies to design the technology to assemble a telescope like that, because it's a very practical thing to do. I'm convinced that in a couple of weeks, myself and a couple of other astronauts could assemble such a telescope with robotic support. We just have to make sure the technology is there, that it would actually work. Lots of people are working on that. I think this is an extra detail, but the decadal survey for astrophysics is planning on what investments do we need to make and what do those future telescopes look like, that we should start in the next decade. So that when you grow up, you can either go up and assemble that telescope, or perhaps be an astronomer and use that telescope to unravel further mysteries of the universe.

Mat Kaplan: What a great vision. Thank you for sharing that with John. Thank you for this past hour, and for that matter, for helping the Hubble to continue to share its vision for perhaps years to come.

John Grunsfeld: Thank you very much Mat. It's been a real pleasure.

Mat Kaplan: Former astronaut and NASA Associate Administrator and Chief Scientist, John Grunsfeld. Again, the video of this live event is at Bruce and What's Up are seconds away.

Kate: Hi, this is Kate from the Planetary Society. How does space spark your creativity? We want to hear from you whether you make cosmic art, take photos through a telescope, write haikus about the planets or invent space games for your family, really any creative activity that's space related. We invite you to share it with us. You can add your work to our collection by emailing it to us at [email protected]. That's [email protected]. Thanks.

Mat Kaplan: Time for What's Up on Planetary Radio. The Chief Scientist of the Planetary Society is Dr. Bruce Betts. He's back with us to explore the night sky and share a random space fact and all the other fun stuff that we have in store, including the space trivia contest. So, stick around for that. Hope you will. I'm glad you're back. How are you holding up?

Bruce Betts: Hunky dory, swell Mat, how about you?

Mat Kaplan: Not bad. Not bad. Not bad. It's getting to be long, this sheltering-in-place. We're still behaving out here at the Kaplan home, but it's getting more and more tempting to get out there.

Bruce Betts: But home is so nice.

Mat Kaplan: I can't complain.

Bruce Betts: Home is where the dogs are.

Mat Kaplan: Well, dog singular in our case, but that'll do, he'll do. Dennis is great. We've got the sky overhead in the backyard, so we've got a lot to look up to.

Bruce Betts: Hey, I can tell you some things to look up to.

Mat Kaplan: Oh, how handy, me always.

Bruce Betts: But also, Venus is pretty much gone away in the evening sky, but I've made special arrangements with Jupiter and Saturn. They'll be coming to the real evening sky, but I've already talked them into coming up in the middle of the night. So, if you're up at midnight-ish, check them out in the east rising together, Jupiter being the brighter of the two. They're also up in the south in the pre-dawn. Also in the pre-dawn, you've got Mars far off to the left of Jupiter. In the evening sky you can also, this one's tough, but you can check out mercury low in the west shortly after sunset, if you've got a clear view to the horizon. It'll be looking like a bright star over there. So, go have fun.

Mat Kaplan: Don't have to go far.

Bruce Betts: Oh, actually one other thing to mention, which is the moon will be joining Jupiter and Saturn on June 7th and 8th making for a lovely little combination.

Mat Kaplan: Nice.

Bruce Betts: Onto This Week In Space History, it was 2003 that Mars Express from the European Space Agency launched, headed towards orbit around Mars, where it's still partying. We should move on to [inaudible 00:54:53].

Mat Kaplan: Talking through a pillow?

Bruce Betts: In my mind.

Mat Kaplan: Nap time.

Bruce Betts: Doug Hurley was the pilot of STS 135, the special mission that was the last human mission launch from US soil and he is the commander of Space X Demo-2, the first human mission to launch from US soil since then.

Mat Kaplan: Which by the time a lot of people hear this, will have happened. It's the bad thing about coming out with this show every Wednesday morning. We won't be able to talk about the launch. Except to wish Bob and Doug Godspeed.

Bruce Betts: Indeed. We should move on to the trivia contest. I noted that the Cygnus cargo spacecraft NG-13, was recently released from the International Space Station. I asked you who was it named after. How'd we do?

Mat Kaplan: Before we get to that, I mean, apparently Northrop of Grumman likes to name these after lots of interesting space heroes. Paavo Kamisha in Belarus said NG-12 was named after Alan Bean, who left those silver pins, astronaut pins on the moon that you were talking about just a few weeks ago.

Bruce Betts: Yeah. Now they've got all sorts of interesting people they've named them after.

Mat Kaplan: Well, I have our winner for this week. Do you want to fill us in on the answer before I reveal her name?

Bruce Betts: Sure. So, the Cygnus cargo spacecraft was named after Major Robert Henry Lawrence Jr. He was a US air force officer and the first African American astronaut. He was unfortunately at age 32, killed in a plane crash in 1967. They chose to honor him as do we.

Mat Kaplan: Like a lot of his apparently classmates among those air force, would be astronauts transferred to NASA. So, he might very well have made it up there, I guess.

Bruce Betts: Yeah. I should say he was selected as an astronaut in the Air Force's Manned Orbital Laboratory Program, which was then canceled. But as you say, a lot moved over to NASA.

Mat Kaplan: So here's our winner, Elizabeth Spath, longtime listener, first time winner in Indiana. Congratulations Elizabeth. We are going to make sure that you get Elizabeth, Kevin Hand's new book, the one that we talked about with Kevin about a couple of weeks ago, Alien Oceans: The Search for Life in the Depths of Space. We are getting all kinds of wonderful comments. Compliments for Kevin on that conversation. The book is at least that good. So Elizabeth, we're glad to have you out there and glad to pass the book along to you as well.

Mat Kaplan: As always, we've got some other stuff from Ola Franzen. This is interesting because, it's not just the Robert H. Lawrence, it's the SS Robert H. Lawrence. Ola Franzen and in Sweden said, "It's amazing they got a steam ship up that high."

Bruce Betts: It takes big rockets.

Mat Kaplan: "Or, is it the list of ship prefixes that needs a little updating?" Ola says, I wonder, is it no longer steamship but spaceship? That'd be cool.

Bruce Betts: Yeah. I believe it would go a spaceship rather than steamship.

Mat Kaplan: A lot of tributes to Mr. Lawrence from our poet Laureate in Kansas State, Fairchild. Northrop Grumman gives their Cygnus spacecraft honored place by naming them for those whose roles were pivotal for space. An African American named Robert Lawrence was the first to be an astronaut, for which we give applause. Mark Daneen in Florida, "Thank you for this. It led me down a Wikipedia rabbit hole that was both sad and uplifting." He adds, "Can we leave racism below the Karman line, please?" Wow, that's a very good suggestion Mark. So far so good, I think, at least lately.

Mat Kaplan: Finally, Tony Knutzen in Minnesota, "Thank you to Robert and the many other men and women who have paid the ultimate price in our ongoing pursuit of the stars." Well done, Tony.

Bruce Betts: That's very nice. Good sentiments. Very nice. Thank you.

Mat Kaplan: Yeah. We're ready for another contest.

Bruce Betts: Here's your question. Who is scheduled to be the first non-American astronaut to launch on a space X crew dragon launch? Go to

Mat Kaplan: So, that is already scheduled? That's interesting. I knew that that's the plan, but I had no idea.

Bruce Betts: Obviously, scheduled missions could move around et cetera. But in terms of as of now, who's scheduled?

Mat Kaplan: You have until Wednesday, June 3rd at 8:00 AM Pacific time to get us the answer to this one. We will have for the winner, how about a book? This looks like a great book. I've only glanced through it. What Stars Are Made Of: The Life of Cecilia Payne-Gaposchkin. I hope is how it's pronounced, it's by Donovan Moore and Jocelyn Bell Burnell an astronaut, a great astronomer in her own right. It's about another pioneering woman astronomer, from the early 20th century primarily. Fascinating story from the look of it. We'll have that book for you.

Mat Kaplan: How about we throw in, and we do mean throw, a Planetary Society rubber asteroid? We are hoping to once again start getting this stuff out from our office, because our heroic colleague Robin Young is a visiting there for at least part of a day each week, and fulfilling some things like this. So, thank you Robin. Hopefully some of you will start actually seeing some of your prizes that have been stuck there for a while. We did warn you. I think with that, we're done.

Bruce Betts: All right, everybody go out there, look up the night sky and think about whatever happened to Microsoft's Snohomish Font. Thank you and goodnight. Snohomish.

Mat Kaplan: Is it gone? How sad. Well, I'm going to stick with the font that I always use, which is, I forget what it's called, but it's the one that-

Bruce Betts: Wingdings?

Mat Kaplan: Wingdings is great, but I've gone with the one that's based on the Lost in Space television series titles.

Bruce Betts: Nice.

Mat Kaplan: He's Bruce Betts, the Chief Scientist of the Planetary Society, who joins us every single week here for What's Up. Planetary Radio is produced by the Planetary Society in Pasadena, California, and is made possible by its members who see beyond the event horizon. Learn how to become one of us at Mark Hilverda is our associate producer, Josh Doyle, composed our theme, which is arranged and performed by Peter Schlosser. Thanks for giving us a rating and a review in Apple podcasts. Stay well. Ad astra.