How the Hubble Telescope became the 'Energizer bunny of spacecraft,' according to one of its astronaut visitors
When you buy through links on our articles, Future and its syndication partners may earn a commission.
John Grunsfeld has a model of the Hubble Space Telescope on his bookshelf. It's right next to a model of a NASA space shuttle, which delivered Hubble to space 35 years ago, and it's no secret why both are there.
Grunsfeld, a former NASA astronaut who has served as both the agency's chief scientist and science division leader, helped Hubble last as long as it has. He flew on no less than three of NASA's five fix-it missions to the iconic Hubble Space Telescope between 1999 and 2009. That final mission was the STS-125 servicing flight on the shuttle Atlantis, which NASA thought would give Hubble at least five more years of life, though the agency hoped to stretch that to 15 years. Next month, NASA will mark the 16th year since that final Hubble service call.
"Because of all of the missions leading up to and our 2009 mission, it's still a state-of-the-art observatory," Grunsfeld, a self-described Hubble hugger, told me in an interview. "Knock on wood, it can go another 10 years. And it won't be a telescope failure [that ends Hubble's life] — it'll be that it's too low in the atmosphere to be able to point steadily."
Even that process would take years, Grunsfeld said.
"So Hubble is, you know, the Energizer bunny of spacecraft, really," he added.
It wasn't always that way. There was a time when Hubble had the potential to become NASA's biggest embarrassment.
That was in 1990, months after NASA first launched Hubble into orbit on the shuttle Discovery on April 24 of that year, and astronomers were eagerly waiting to see the first photos from the space telescope. The problem? The highly anticipated images were blurry. Hubble had a flaw in its mirror called a "spherical aberration." It would require a new mission, a repair job in space by astronauts, to fix the faulty optics by installing new gear. Luckily, upgrading Hubble was something NASA always planned to do.
"When it was launched, it had the spherical aberration, so it was a great disappointment to astronomers," said Grunsfeld, who was working in X-ray and gamma-ray astronomy at the California Institute of Technology at the time. He would join NASA as an astronaut in 1992, where he'd provide mission support for the crew of STS-61, the 1993 mission to repair Hubble's faulty eyes with corrective optics.
"Because it had been designed to be serviceable, and not just serviceable but extreme serviceability, we were able to save it with the STS-61 crew," Grunsfeld said.
Related: Fixing the Hubble Space Telescope: A servicing mission timeline
Grunsfeld admitted that he wasn't Hubble's biggest fan as a gamma-ray astronomer in 1990. His work relied on NASA's Compton Gamma Ray Observatory and Chandra X-ray Space Telescope, but Hubble was dominating funding discussions at the time.
"Hubble was not popular, unless you were a Hubble astronomer, because it was taking a lot of funding and a lot of attention," Grunsfeld said. "So when the spherical aberration was discovered, I thought this was really going to hurt astronomy. Now, of course, I was completely wrong, because Hubble works so well with the other observatories."
That STS-61 mission, commanded by Richard Covey, not only installed the corrective optics for Hubble's vision but also replaced two sets of gyroscopes for positioning, the control units for them, electrical fuse plugs, the space telescope's solar arrays. Spacewalking astronauts also installed the then-new Wide Field Planetary Camera 2 instrument (replacing the old one), among other upgrades.
Subsequent servicing missions would make even more repairs and upgrades, including Hubble's main camera, which is now the Wide Field Planetary Camera 3, which was installed in 2009 by Grunsfeld and fellow NASA astronaut Andrew Feustel on STS-125. During one exceptional spacewalk repair on STS-125, Michael Massimino and Michael Good had to rip a stuck handrail off Hubble by hand in order to repair a broken spectrograph, which itself was unprecedented. The astronauts had to unscrew 117 small screws (without losing any) and then swap out a broken power supply board to fix something never designed to be fixed in space.
Grunsfeld has one of those tiny screws to this day.
He credits not only the astronauts on the repair flights but also the countless engineers and scientists on Earth who designed Hubble to be serviced, then devised new and more modern instruments to squeeze ever more science out of the aging observatory.
STS-125, the final Hubble servicing mission, almost never even happened. NASA canceled it in 2004 in the wake of the tragic 2003 Columbia shuttle disaster that killed seven astronauts. Grunsfeld, who served as NASA chief scientist from 2003 to 2004, was asked at the time what kind of life-extension options for Hubble were possible. Grunsfeld and NASA flight director Chuck Shaw helped develop a plan that called for two space shuttles, one to visit Hubble and a second on standby as a rescue ship, that led to then-NASA Administrator Mike Griffin greenlighting one final mission in 2006.
"The reason why Hubble is still a great observatory and producing world-class science is because we were able to change out the instruments," Grunsfeld said. "It's that ability to change out instruments that allows you to have a 35-year-old observatory that still does the kind of science it does."
There are no more servicing missions planned for the Hubble Space Telescope, though at least one billionaire has pitched a plan for a final visit to give it more life. Indeed, during the STS-125 mission, Grunsfeld and his crew added a docking device so a future vehicle could attach to Hubble to either reboost its orbit or help it leave orbit to burn up safely in Earth's atmosphere. NASA decided that a private mission, devised by Jared Isaacman (Trump's pick for the next NASA administrator) and SpaceX, wasn't advisable at this time. The Hubble telescope program is also facing potential budget cuts, like much of NASA, making another visit unlikely.
Still, the science from Hubble has been both groundbreaking for astronomers and breathtaking for the public.
Throughout its career, Hubble data has allowed scientists to prove the existence of black holes, refine our understanding of the age of the universe and peer back to within a few hundred million years of the Big Bang that started it all, Grunsfeld said. And there were surprises, too. Like when Hubble watched Comet Shoemaker-Levy 9 crash into Jupiter in 1994, something we know can happen regularly."We saw that right away," Grunsfeld said of the comet crash.
Related: The Hubble Telescope is in 'excellent technical condition' on its 35th birthday, its chief scientist says
Related Stories:
— Happy 35th birthday, Hubble Telescope! 10 times the iconic observatory blew astronomers' minds (photos)
— Hubble snaps stunning portraits of Mars, a celestial moth and more in 35th anniversary photos
— The Hubble Space Telescope turns 35 as NASA budget cuts loom. How many more birthdays will it have?
— Can Hubble still hang? How the space telescope compares to its successors after 35 years of cosmic adventures
— Fixing the Hubble Space Telescope: A timeline of NASA's shuttle servicing missions
Grunsfeld, who retired from NASA in 2016 after also serving as associate administrator for science missions, said he's especially pleased that Hubble has lasted long enough to serve alongside the James Webb Space Telescope, an infrared observatory that is the most powerful space telescope ever built. It launched in December 2021, and the two flagships of astronomy now work together with other telescopes to peel back layer after layer of cosmic time.
"The science case is even stronger for Hubble now, 35 years after launch, because we have the James Webb observatory, and the two work so well together." Grunsfeld said. "As associate administrator, that was my dream."
But perhaps the biggest surprise, he said, was the wonder and awe Hubble regularly revealed about the universe to the public. The science was expected; the spectacle of the cosmos was a bonus.
"More than half of people on planet Earth have never known a world without the Hubble Space Telescope," Grunsfeld said. "From a NASA perspective, Hubble is probably NASA's best ambassador, you know, in the space business."
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Digital Trends
3 hours ago
- Digital Trends
NASA astronaut's first ISS time-lapse is a real stunner
NASA astronaut Jonny Kim has shared his first-ever time-lapse from aboard the International Space Station (ISS) — and it's a real stunner. The dramatic 68-second clip shows a changing view of Earth as the space-based facility orbits our planet at an altitude of about 250 miles. Recommended Videos 'My first time-lapse,' Kim wrote in a social media post that included the video (below). Kim said he managed to nail it thanks to some time-lapse tips shared by fellow astronaut Nichole Ayers. 'After seeing the result, I told her this felt like fishing,' Kim wrote. 'Prepping the camera, the angle, the settings, the mount, then setting your timer and coming back to hope you got a catch. And after catching my first fish, I think I'm hooked.' My first time-lapse. Thanks to some instruction and tips from @Astro_Ayers, I caught my first aurora. After seeing the result, I told her this felt like fishing. Prepping the camera, the angle, the settings, the mount, then setting your timer and coming back to hope you got a… — Jonny Kim (@JonnyKimUSA) June 6, 2025 The video shows the space station flying into the night, with city lights in Asia and Australia visible far below, and bright stars shining in the far distance. A short while later, a gorgeous aurora appears over the horizon before filling much of the frame. Toward the end of the clip, one of the station's solar arrays also come into view. Auroras are natural light displays in Earth's sky, caused by charged particles from the sun colliding with the Earth's magnetic field and atmosphere. While also viewable from parts of Earth, astronauts on the ISS can also enjoy a unique view of this natural wonder. Indeed, for most astronauts, witnessing auroras is one of the highlights of their time in orbit. Earlier this year, another NASA astronaut, Don Pettit, shared a dramatic view of an aurora, captured as the ISS flew directly over it. Kim arrived at the space station with two Russian cosmonauts after launching aboard a Soyuz spacecraft in April this year. With another four months of his mission left to run, hopefully the American will have time to create more clips similar to his first outstanding effort.
Yahoo
4 hours ago
- Yahoo
How to see the 'Horse and Rider' in the Big Dipper's handle this summer
When you buy through links on our articles, Future and its syndication partners may earn a commission. At around 10 p.m. local daylight time on these warm June evenings, face north and look overhead to see the seven stars that compose the famous Big Dipper. At this time of the year, the handle appears to stand almost straight up while the bowl appears tilted down; draining its unknown contents toward the right. The Dipper is not a constellation in of itself, but an asterism, a prominent pattern or group of stars, typically having a popular name, belonging to a specific constellation. For most sky gazers, the Big Dipper is probably the most important group of stars in the sky. For anyone in the latitude of New York (41 degrees North) or points northward, it never goes below the horizon. It is one of the most recognizable patterns in the sky and thus one of the easiest for the novice to find. Of greatest importance is the ability to utilize the Big Dipper to locate Polaris, the North Star. This is made possible by the two bright stars that mark the outer edge of the bowl of the Big Dipper. These two stars — Dubhe and Merak — are known as the Pointers, because they always point to Polaris. Just draw a line, in your imagination, between these two stars and prolong this line about 5 times, the way our map shows; this line will ultimately hit a moderately bright star. That will be Polaris. Even those who live well south of the equator can see the Big Dipper now. During autumn in the Southern Hemisphere, it appears to hover upside-down above the northern horizon for those down to about latitude 30-degrees south. That includes the northern two-thirds of South America and virtually all of Africa. In his classic constellation guide, "The Stars — A New Way to See Them," author H.A. Rey sketched a cute cartoon on page 24 of a mother kangaroo and its joey above the caption: "The Dipper? Never seen it ..." And yet for the northern two-thirds of Australia, during April, May and June, the Dipper is plainly visible hanging low above the northern horizon. The middle star in the Dipper's handle is Zeta Ursae Majoris; the Greek letter is the given name, and the possessive of the Latin name of its constellation. In this case Ursa Major, the Great Bear — is its family name. But this particular star is far better known as "Mizar," derived from the Arabic meaning for "wrapping" or "cover." With just your eyes alone, if you look carefully, you'll notice that Mizar appears to have a fainter companion by the name of Alcor, also derived from the Arabic, meaning "faint one." The Persian Al Kazwini stated during the 13th century that people "tested their eyesight by this star." TOP TELESCOPE PICK: Want to see Alcor and the other stars of the Big Dipper? The Celestron NexStar 4SE is ideal for beginners wanting quality, reliable and quick views of celestial objects. For a more in-depth look at our Celestron NexStar 4SE review. Mizar and Alcor were known as the "Horse and Rider" to the ancient Arabs and the Arabian writer Al Firuzabadi, in the 14th century referred to Alcor as Al Sadak, "The Test" or "The Riddle." So, when the ancient Arabs remarked: "He can see Alcor," they were alluding to someone who had normal vision. Why not test your own eyesight by looking for Alcor tonight? Alcor is one-fifth as bright as Mizar and the two stars are separated by roughly one-third of the apparent diameter of the moon. Both stars are located about 83 light-years away and recent observations suggest that Alcor is traveling around Mizar in a wide orbit that takes 750,000 years to complete. Binoculars provide a better view of this pair, but there's more to see here than many skywatchers realize. As an example, Mizar, is in itself a true binary star; one of the first to be observed and identified as a binary pair by astronomers in the 17th century. A binary star is two or more stars that are physically connected with each other and are "locked" or connected together by gravity. They actually orbit each other in a fashion similar to the Earth and the planets orbiting the sun or the moon orbiting the Earth. To see the companion of Mizar you'll need a small telescope and an eyepiece providing a magnification of at least 50-power. Between Mizar and Alcor and a little to their south is an 8th-magnitude star that was once mistaken for a new planet. In December 1722, the German professor Johann Georg Liebknecht announced that this object had just moved into its present position. He christened his "planet" Sidus Ludoviciana — Ludwig's Star — to flatter his local sovereign Ludwig V of Hesse-Darmstadt in hopes of being granted money. The object never moved again. Liebknecht disappeared in a hail of ridicule, but amazingly the name of the "faux" or "ersatz" planet remains to this very day! If you draw a line east from Mizar through Alcor, you'll come across a 5th-magnitude star, glowing with a distinct ruddy hue. That's 83 Ursae Majoris, a red giant star roughly 80 times larger and about 1,300 times more luminous than the sun. It's located at a distance of 580 light-years from us. If you continue onward along the same line at about twice the distance past 83, you'll come to the big, but dim galaxy M101. Under a dark sky M101 appears in 7 x 50 and larger binoculars in much the same way that its discoverer Pierre Méchain described it in 1781: "very obscure and pretty large." It is popularly known as the "Pinwheel Galaxy," and at 21 million light years, it is one of the closer spiral galaxies to our Milky Way. But in order to perceive its spiral structure, you'll need a rather large telescope, very dark skies and a low-power eyepiece. Finally, our familiar Dipper will not last forever. Of the seven stars that make up this pattern, five apparently belong to a loosely joined swarm of stars, all hurtling through space at roughly the same speed and the same direction. These five range in distances from 78 to 84 light-years from Earth. Two of the stars, however — Dubhe (the northern Pointer) and Alkaid (the star at the end of the handle) — are not part of the swarm and appear to be rushing at even greater speeds in the opposite direction. Alkaid is 101 light-years away, while Dubhe is 124 light-years distant. These opposing motions will slowly alter the form of the Big Dipper. In short, the Dipper is slowly going to pieces. The bent handle will bend still more as time wears on, while the bowl will spread. Granted, it will still remain a fairly convincing dipper for about the next 25,000 years, but 50,000 years (or 2,000 generations) from now it will be hopelessly out of shape. If you're looking for a telescope or binoculars to observe the night sky, our guides for the best binoculars deals and the best telescope deals now can help. Our guides on the best cameras for astrophotography and best lenses for astrophotography can also help you prepare to capture the next skywatching sight. Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, Sky and Telescope and other publications.
Yahoo
4 hours ago
- Yahoo
NASA raises the odds that an asteroid could hit the moon in 2032
When you buy through links on our articles, Future and its syndication partners may earn a commission. Asteroid 2024 YR4, once considered the highest impact risk to Earth ever recorded, is back in the spotlight — this time due to a slight increase in the chance that it could impact the moon in 2032. Although now too distant to observe from Earth, the asteroid briefly came into view in May for the James Webb Space Telescope (JWST). Using data from the telescope's Near-Infrared Camera, a team led by Andy Rivkin of the Johns Hopkins Applied Physics Laboratory refined predictions of where 2024 YR4 will be on Dec. 22, 2032 by nearly 20%. That revised trajectory nudged the odds of a lunar impact from 3.8% to 4.3%, according to a NASA update. "As data comes in, it is normal for the impact probability to evolve," the statement read. Even if a collision occurs, "it would not alter the moon's orbit." Astronomer Pawan Kumar, a former researcher at the Indian Institute of Astrophysics in Bengaluru, agrees the moon is safe, noting a collision with the moon "won't be a cause for concern" because any moon debris blasted into space from the impact "blow up in Earth's atmosphere if any of it makes it to near-Earth space." First detected on Dec. 27 last year, 2024 YR4 is estimated to be about 174 to 220 feet long (53 to 67 meters), or about the size of a 10-story building. The asteroid quickly grabbed headlines for having more than a 1% chance of striking Earth, the highest recorded for any large asteroid. Follow-up observations in January and February saw the impact risk climb from 1.2% to a peak of 3.1%. The asteroid's projected trajectory at the time suggested it could cause blast damage across a wide potential impact zone, spanning the eastern Pacific, northern South America, Africa and southern Asia. If it enters Earth's atmosphere over the ocean, NASA estimated it would be unlikely to trigger significant tsunamis, but an airburst over a populated city could shatter windows and cause minor structural damage. However, the impact risk dropped sharply as additional orbital data came in. By Feb. 19, the probability had fallen to 1.5%, and then to 0.3% the next day. On Feb. 24, NASA announced an official "all clear" on social media, reporting the impact probability had dropped to just 0.004% and that the asteroid is "expected to safely pass by Earth in 2032." Further analysis has since allowed scientists to rule out any risk to Earth, not only in 2032 but from all future close approaches as well. Data from telescopes in Chile and Hawaii recently suggested the space rock originated in the central main belt between Mars and Jupiter and gradually shifted into a near-Earth orbit. Since mid-April, the asteroid has been too far away and too faint to be seen from Earth. It will swing back into view in 2028, giving scientists another chance to observe the asteroid and further refine its orbit using both JWST and ground-based telescopes. In particular, scientists will aim to gather more data on its shape and composition, which are key factors in understanding both its behavior and potential impact effects. RELATED STORIES — Odds of an asteroid impact in 2032 just went up. Here's why experts say you shouldn't worry — Asteroid apocalypse: How big must a space rock be to end human civilization? — Astronomers discover 196-foot asteroid with 1-in-83 chance of hitting Earth in 2032 While 2024 YR4 no longer poses any danger, it provided scientists with a rare, real-world opportunity to rehearse the full scope of planetary defense strategy, ranging from initial detection and risk analysis to public messaging. It was "an actual end-to-end exercise" for how we might respond to a potentially hazardous asteroid in the future, said Kumar. "2024 YR4 is a tailor-made asteroid for planetary defense efforts," he said. "It has everything it takes to get our attention."
