A quarter-century ago, this week, four powerful ultraviolet and X-ray “eyes” peered out from the payload bay of the Earth-circling Shuttle Columbia to scour the distant reaches of the Universe, observing some of its most mysterious phenomena, from quasars to active galactic nuclei and from supernovae remnants to white dwarfs. Under an alternate history, ASTRO-1 might have been aboard the next shuttle flight after Challenger’s tragic Mission 51L, and might have been directed to explore Halley’s Comet, as it made its 75-yearly passage through the inner Solar System in the winter of 1985-86. As circumstances transpired, it was not to be, and in the aftermath of Challenger’s loss ASTRO-1 found itself manifested onto STS-35 and scheduled for a mid-1990 launch. However, the gremlins of misfortune had one more card to play and the mission was grounded until December 1990 by a seemingly intractable series of hydrogen leaks.
In its original incarnation, ASTRO-1 comprised three ultraviolet instruments: the Johns Hopkins University’s Hopkins Ultraviolet Telescope (HUT), the University of Wisconsin at Madison’s Wisconsin Ultraviolet Photopolarimeter Experiment (WUPPE), and, lastly, the Ultraviolet Imaging Telescope (UIT), provided by NASA’s Goddard Space Flight Center (GSFC) of Greenbelt, Md. In anticipation of the observations of Halley’s Comet, a Wide Field Camera (WFC) was also added, but deleted in the aftermath of Challenger and replaced by another instrument, known as the Broad Band X-Ray Telescope (BBXRT), in order to shed new light on Supernova 1987A in the Large Magellanic Cloud. In the early post-Challenger era, BBXRT was baselined to fly aboard a 1992 mission known as the Shuttle High Energy Astrophysics Laboratory (SHEAL), mounted into the orbiter’s payload bay by means of a unique Two-Axis Pointing System (TAPS), and unlike the ASTRO-1 telescopes was not controlled by the astronauts, but directly from the ground. However, BBXRT was completed ahead of schedule and added to the ASTRO-1 payload.
Following a painful summer of delays in 1990, the shuttle fleet returned to flight with a rapid-fire salvo of missions in October and November, delivering the Ulysses solar polar orbiter and a classified Department of Defense payload aloft. By late November, with Columbia out on Pad 39B at the Kennedy Space Center (KSC) in Florida, tracking a 2 December liftoff on STS-35, all seemed ready and weather conditions were expected to be 70-percent-favorable, despite the ominous presence of a tropical storm off Cuba. Commanding the mission was Apollo-Soyuz Test Project (ASTP) veteran Vance Brand—who, aged 59, became the oldest human ever to command a shuttle flight and the then-oldest human ever to journey into space—but it seemed that the mission was laced with misfortune.
That misfortune was understandable, for in its original guise of Mission 61E, ASTRO-1 was only five weeks from launch on 28 January 1986, when Challenger was lost in the skies of Cape Canaveral, a mere 73 seconds into her flight. Then, following the assignment of the bulk of the original crew to STS-35 in the fall of 1988, more cruel luck befell the flight when Commander Jon McBride resigned from NASA. He was later replaced by Brand, with an originally targeted launch date of early 1990, although this slipped progressively through the year. In the mind of Mission Specialist Jeff Hoffman, the fact that ASTRO-1 no longer had a comet on its observations books was a positive sign. “We all know comets are harbingers of bad news,” he said before launch. “This time, we have no comet, so we’re going to go.”
And go they did. At 1:49 a.m. EST on 2 December, Columbia roared aloft, lighting up the darkened Florida skies and most of the United States’ eastern seaboard. The launch suffered a brief, 21-minute delay, due to concern about clouds beneath the 8,000-foot (2,430-meter) “ceiling” needed to monitor the first two minutes of ascent, but was exceptionally smooth. Sitting on Columbia’s flight deck, Hoffman would never forget the awe-inspiring sensation of blasting off at night. As the vehicle ascended from the pad, cleared the launch tower and began a computer-controlled “Roll Program” maneuver to establish itself on the proper azimuth for a 28.45-degree-inclination orbit, he remembered looking back over his shoulder through the overhead windows to see the ground literally glow at the instant of Solid Rocket Booster (SRB) ignition at T-0. Later, when the boosters burned out and were jettisoned, Hoffman and the other three men on the flight deck—Commander Brand, Pilot Guy Gardner, and the mission’s flight engineer, Mike Lounge—were astonished as the entire cockpit was eerily bathed in light.
Even though this was his fourth launch into space, it was one to savor for Vance Brand, since it was his first at night. “You had the feeling you were lighting up all that part of Florida,” he told the NASA oral historian. “It was like night flying in an airplane. You had to really have your lights adjusted and pay attention to your gauges. You couldn’t really tell much about what was going on outside. You couldn’t see the horizon very well.” The night launch oriented Columbia to ensure that her passage through the South Atlantic Anomaly (SAA)—where the Van Allen radiation belt “dips” toward the ionosphere—occurred mainly during orbital daytime. High-energy particles were already known to adversely affect instrument performance and increased “background” levels in sensitive scientific detectors. Since this natural background, which consists of scattered light and ultraviolet atmospheric airglow emissions, was also higher on the daylit portion of each orbit, it preserved the nighttime passes for ASTRO-1 to focus on its faintest celestial targets.
Observation of those targets began crisply and activation of the payload commenced almost as soon as the pilots had established Columbia in her operational orbit. The “red” team, consisting of Mission Specialist Bob Parker and Payload Specialist Ron Parise, led by Gardner, took charge of activating ASTRO-1 and its support equipment. Meanwhile, the “blue” team of Hoffman and Payload Specialist Durrance and shift leader Lounge bedded down for an abbreviated sleep period. They would awaken for their first 12-hour work duty at 1:00 p.m. EST on 2 December. Although not specifically attached to either shift, Brand tended to anchor his schedule across both teams, which enabled him to maintain a “big picture” of operations and transfer knowledge from one team to the other.
As the first use of the new Spacelab Mission Operations Control Facility at NASA’s Marshall Space Flight Center (MSFC) in Huntsville, Ala., ASTRO-1 got off to an exceptionally smooth start when, at 7:56 a.m. EST on the 2nd—just six hours after launch—Parker opened his first scientific communications session with “Huntsville, this is ASTRO.” Michelle Snyder, the crew interface co-ordinator in Huntsville, quickly responded, telling Parker that everyone was “really excited” and “looking forward to a great ten-day mission and a lot of terrific astronomy.” Aboard Columbia, Parise piped up. “Michelle, we know there’s a lot of people down there that did a lot of work on this mission and we’re hoping to make it a real success for everybody. Let’s get this show on the road.”
By this time, the red team had switched on the BBXRT and at 7:36 a.m. Parker received a go-ahead to unlatch and raise the Instrument Pointing Sytem (IPS) and the three ultraviolet telescopes from their horizontal position in the payload bay. The process took less than seven minutes, and by the time STS-35 was 16 hours old and Lounge’s blue team had assumed duty, the telescopes had sailed through their initial checks and were ready for calibration. One observation of the star Beta Doradus, using HUT, was particularly lauded by Sam Durrance. Located in the constellation of Dorado (the Swordfish), the star had been chosen for its suitability when aligning and focusing the telescopes. The sighting was part of the so-called Joint Focus and Alignment process, whereby all three ASTRO-1 instruments were trained on a common target as a prelude for upcoming observations. Unfortunately, a computer failure in the WUPPE prevented it from participating in the alignment. Ground-based engineers diagnosed the problem as having been caused by an unactivated heater, and, when this was powered up, early on the 3rd, the WUPPE’s checkout got underway.
Overall, the mission had gotten off to a fine start. Typically, the “duty” Mission and Payload Specialists used a pair of Spacelab keyboards and the two Data Display Units (DDUs) to command the IPS and the telescopes. Closed circuit monitors provided images of the starfields under observation and enabled the astronauts to check the data. Observations typically required between 10 minutes and a full hour to complete. Meanwhile, shift leaders Gardner and Lounge were responsible for firing Columbia’s Reaction Control System (RCS) thrusters to keep the orbiter properly oriented.
Yet now, the first scientific Spacelab mission in the post-Challenger era was at risk.
The second part of this article will appear tomorrow.