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The space shuttle Discovery went into orbit 30 years ago today with the Hubble Space Telescope in its payload bay.
Charlie Bolden, who served as a pilot for the STS-31 shuttle mission, remembers the five-day space flight as if it were yesterday. “What stands out the most in my mind are all the things that didn’t go well,” Bolden recalled in an interview.
It is true. Although astronomers would not discover that the Hubble Space Telescope had a serious problem with its mirror until a few weeks after Discovery landed, the deployment mission was not without difficulties. The crew arrived within minutes of embarking on an emergency spacewalk and even had contingency plans to bring Hubble back to Earth if necessary.
The mission was novel from the start, with a planned orbit 612 km above the planet’s surface that required the vehicle to fly higher than any shuttle mission to date. The telescope’s deployment came a day after the shuttle reached orbit and involved a complicated sequence of events. After disconnecting the telescope from the shuttle’s power source, the astronauts would use a robotic arm to move the instrument to pay for the shuttle’s payload, open its solar panels, and finally free the telescope.
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“From the moment we disconnected Hubble from the shuttle’s power, we had two clocks running,” said Bill Reeves, who was the mission’s flight director and oversaw operations from the Johnson Space Center. “The telescope was battery powered from that point on, and there was a limited supply. And with the telescope attached to the arm, the shuttle had to be adrift, since propeller firing could damage the instrument.”
When ground controllers instructed the telescope to begin deploying its two solar panels, one of the panels did not do so correctly. Minutes were converted to hours when field engineers solved the problem. Reeves had a contingency plan for this, of course. It involved sending astronauts Bruce McCandless and Kathryn Sullivan off the shuttle to manually deploy the matrices.
Within hours of the test, with Hubble’s batteries drained and the shuttle starting to spin without attitude control, Reeves ordered McCandless and Sullivan to get dressed and enter the airlock. They depressurized from 14.7 psi to 5 psi and performed the space suit leak checks, the final step before fully depressurizing the airlock, opening the hatch, and exiting into space.
While Reeves was considering whether to issue this order to exit, the engineers said they thought they had identified a problem with the software that controlled the voltage in the solar array. They proposed that making a small change would fix the problem. This worked, and the second solar array unfolded alongside its companion. However, because the telescope had yet to be deployed and the robotic arm retracted, Reeves kept McCandless and Sullivan in the airlock, without even a window to watch the Hubble telescope float away.
Deployment of the Hubble Space Telescope solar panel panel during STS-31.
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“They were the only two people on the planet who could not see the Hubble deployment,” Reeves said. To this day, he added, Sullivan still jokingly asks if he did it on purpose.
After Hubble was deployed, the shuttle retreated half an orbit away, in the event of an immediate problem that the crew needed to fix. (There was not, since the scientific commissioning of the instrument would not take place in a couple of weeks). If Hubble’s problems were serious enough, the STS-31 crew had plans to return the telescope to Earth in Discovery’s payload bay. The shuttle was slated to land on the longest runway at Edwards Air Force Base in California, rather than Florida, due to the possibility of becoming heavier, with a damaged Hubble in tow.
Because there were no apparent problems while in orbit, the astronauts were given permission to return five days after launch. When the shuttle landed in California, Reeves recalls telling his flight controllers, “You have no idea what you just did.” The Hubble Space Telescope, he said, would change the way humans looked at the stars.
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For a time, Bolden remembers being on top of the world after landing. Like everyone else, astronauts anxiously awaited the first image from the telescope, a photo of a distant star called HD96755 captured on May 20, 1990. Their euphoria was crushed when the first image turned out to be blurry and only marginally better than the ground. based telescopes. Soon, astronomers realized that the telescope had a deformed mirror.
“Morale just fell to the bottom,” Bolden said. “NASA became the worst part of the jokes worldwide. We were a huge hit with all the nightly talk shows for about three years.”
But then something funny happened. NASA activated its Apollo 13 muscle memory and, over the course of the next three years, planned a meticulous service mission to fix the mirror, upgrade its instruments, and bring in a new and more powerful array of solar panels. In December 1993, the space shuttle Endeavor conducted an 11-day service mission that included five spacewalks. Story Musgrave, who had worked in Hubble development since the early 1970s, served as the primary spacewalker.
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A gallery of some of Hubble’s biggest hits: the SDSS J1038 + 4849 galaxy cluster, with bright galaxies creating the eyes and nose, and gravitational lensing effects causing the characteristic curves.
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The iconic Pillars of Creation in the Eagle Nebula, taken with the Wide Field Planetary Camera 2.
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The same location, photographed with the updated Wide Field Camera 3.
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A Hubble image of Eta Carinae, a hypergiant star (more than 100 times the mass of the Sun) that has undergone two major explosions, creating a large debris nebula. The star will eventually experience a supernova.
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An image created to celebrate Hubble’s 16th birthday, this is a composite of the galaxy Starburst Messier 82.
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Aim at Hubble at an apparently empty part of the sky and wait 10 days. That’s the recipe behind the Hubble Deep Field image, which captures galaxies that date back to the dawn of the Universe.
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The gravitational interactions of these two galaxies in Arp 273 make this incredible image, which has been compared to a cosmic rose.
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Hubble’s 20th anniversary photo is of a feature of the Carina Nebula, a star-forming region that includes Eta Carinae, which appeared earlier.
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The Horse Head Nebula photographed in the infrared. This feature can be found within the Orion constellation.
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Arp 148, the aftermath of a collision between two galaxies.
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Sometimes Hubble is aimed at objects closer to your home. Here, Jupiter’s Great Red Spot is shown near two smaller companions.
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The Arp catalog contains nothing more than unusual-shaped galaxies, which are generally the product of collisions. Here, two galaxies (NGC 6050 and IC 1179) combine to form the structure known as Arp 272.
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A planetary nebula called NGC 6751. These features have nothing to do with planets. Instead, they are created when a large star expels gas and then illuminates it from within.
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This shows two galaxies colliding. The collision has caused an explosion of star formation in the space between them (seen in blue to the left of the center). The collision has also created the galaxy’s long spiral tail on the right.
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Westerlund 2, a group of newly formed stars, in a composite of images taken from more than one Hubble camera. The image was released to celebrate Hubble’s 25th anniversary in space.
“The machine had a very bad start,” he said. “Putting the wrong mirror on the telescope was criminal negligence. I forgive the mistakes, but that was much worse than a mistake. That is not a good story.”
What followed, however, is a good story. In the past 27 years, and four additional service missions, NASA and its astronauts have improved the instrument beyond the dreams of its original planners. Hubble has emerged as arguably the most important scientific instrument of all time, both illuminating astronomers about the nature of the universe and transcending science into popular culture.
“I was not ready for the power of observations,” said Musgrave. “Compared to some of the big telescopes on Earth, Hubble is such a small telescope. But it has clear vision. People love images, not just for science but for their beauty. It says something about who we are.”
